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Einziger T, Devor T, Ben-Shachar MS, Arazi A, Dinstein I, Klein C, Auerbach JG, Berger A. Increased neural variability in adolescents with ADHD symptomatology: Evidence from a single-trial EEG study. Cortex 2023; 167:25-40. [PMID: 37517356 DOI: 10.1016/j.cortex.2023.06.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 05/17/2023] [Accepted: 06/09/2023] [Indexed: 08/01/2023]
Abstract
Increased intrasubject variability of reaction time (RT) refers to inconsistency in an individual's speed of responding to a task. This increased variability has been suggested as a fundamental feature of attention deficit hyperactivity disorder (ADHD), however, its neural sources are still unclear. In this study, we aimed to examine whether such inconsistency at the behavioral level would be accompanied by inconsistency at the neural level; and whether different types of neural and behavioral variability would be related to ADHD symptomatology. We recorded electroencephalogram (EEG) data from 62 adolescents, who were part of a prospective longitudinal study on the development of ADHD. We examined trial-by-trial neural variability in response to visual stimuli in two cognitive tasks. Adolescents with high ADHD symptomatology exhibited an increased neural variability before the presentation of the stimulus, but when presented with a visual stimulus, this variability decreased to a level that was similar to that exhibited by participants with low ADHD symptomatology. In contrast with our prediction, neural variability was unrelated to the magnitude of behavioral variability. Our findings suggest that adolescents with higher symptoms are characterized by increased neural variability before the stimulation, which might reflect a difficulty in alertness to the forthcoming stimulus; but this increased neural variability does not seem to account for their RT variability.
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Affiliation(s)
- Tzlil Einziger
- Ruppin Academic Center, Department of Behavioral Sciences, Emek Hefer, Israel.
| | - Tali Devor
- Department of Psychology, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Mattan S Ben-Shachar
- Department of Psychology, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Ayelet Arazi
- Department of Neurophysiology and Pathophysiology, University Medical Center Hamburg-Eppendorf, Germany
| | - Ilan Dinstein
- Department of Psychology, Ben-Gurion University of the Negev, Beer Sheva, Israel; Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Beer Sheva, Israel; National Autism Research Center of Israel, Beer Sheva, Israel
| | - Christoph Klein
- Department of Child and Adolescent Psychiatry, Medical Faculty, University of Freiburg, Germany; Department of Child and Adolescent Psychiatry, Medical Faculty, University of Cologne, Germany; 2(nd) Department of Psychiatry, National and Kapodistrian University of Athens, Greece
| | - Judith G Auerbach
- Department of Psychology, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Andrea Berger
- Department of Psychology, Ben-Gurion University of the Negev, Beer Sheva, Israel; Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Beer Sheva, Israel
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2
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Atypical Arousal Regulation in Children With Autism but Not With Attention-Deficit/Hyperactivity Disorder as Indicated by Pupillometric Measures of Locus Coeruleus Activity. BIOLOGICAL PSYCHIATRY. COGNITIVE NEUROSCIENCE AND NEUROIMAGING 2023; 8:11-20. [PMID: 33930603 DOI: 10.1016/j.bpsc.2021.04.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 04/15/2021] [Accepted: 04/15/2021] [Indexed: 01/11/2023]
Abstract
BACKGROUND Atypical arousal regulation may explain slower mean reaction time (MRT) in autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder compared with typical development. The locus coeruleus-norepinephrine system (LC-NE) underlies arousal regulation and adapts its activity to the utility of a task. LC-NE tonic and phasic activity are indexed by baseline pupil size (BPS) and stimulus-evoked pupillary response (SEPR). METHODS The study assessed pupillometry in ASD (n = 31, 3 female/28 male), attention-deficit/hyperactivity disorder (n = 28, 3 female/25 male), and typically developing control subjects (n = 31, 16 female/15 male) during a visuospatial reaction-time task that manipulates arousal by conditions with low and high task utility. We estimated linear mixed models of BPS, SEPR, and MRT in a per-trial analysis to investigate arousal regulation of task performance. RESULTS Slower MRT occurred in the ASD group compared with the typically developing control group during low-utility conditions while controlling for dimensional ASD and attention-deficit/hyperactivity disorder symptoms. In low-utility conditions, BPS and SEPR were inversely related and both were associated with faster MRT. Increased ASD symptoms across groups were associated with higher BPS during low-utility conditions. Changes in BPS and SEPR between task-utility conditions were smaller in the ASD group. CONCLUSIONS Slower visuospatial task performance in ASD is specific to low task utility. Arousal was associated with task performance and showed altered activity in ASD. Increased BPS during low-utility conditions suggested increased LC-NE tonic activity as an ASD symptom marker in children. Smaller changes in BPS and SEPR in ASD indicated attenuated LC-NE activity adaptation in response to high-utility conditions. Slower performance and atypical arousal regulation are probably associated with attenuated LC-NE activity adaptation.
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3
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Schulz-Zhecheva Y, Voelkle MC, Beauducel A, Biscaldi M, Klein C. Intra-Subject Variability, Intelligence, and ADHD Traits in a Community-Based Sample. J Atten Disord 2023; 27:67-79. [PMID: 36082454 DOI: 10.1177/10870547221118523] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE The present study investigates the predictive validity of intra-subject variability (ISV) for ADHD traits in a community-based sample and the stability of the relationship between ISV and fluid intelligence (gf) across the continuum of ADHD traits. METHOD Age-residualized data from 426 participants (8-18 years, 6% ADHD) was used to investigate whether ex-Gaussian and DDM parameters derived from simple choice-reaction-time tasks can predict continuously assessed ADHD traits. Multiple-Group-Analyses and Latent-Moderated-Structural-Equations were used to test whether ADHD traits moderate the relationship between ISV and gf. RESULTS σ and μ of the ex-Gaussian model as well as DDM parameters drift rate (v) and boundary separation (a) significantly predicted general ADHD traits, while τ predicted attention difficulties specifically. Across the ADHD continuum, σ and v were significant predictors of gf. CONCLUSION The results confirm the link between ISV and ADHD. The relationship between ISV and gf appears stable across the ADHD continuum.
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Affiliation(s)
| | | | | | | | - Christoph Klein
- University of Freiburg, Germany.,University of Cologne, Germany.,National and Kapodistrian University of Athens, Germany
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4
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Vainieri I, Martin J, Rommel AS, Asherson P, Banaschewski T, Buitelaar J, Cormand B, Crosbie J, Faraone SV, Franke B, Loo SK, Miranda A, Manor I, Oades RD, Purves KL, Ramos-Quiroga JA, Ribasés M, Roeyers H, Rothenberger A, Schachar R, Sergeant J, Steinhausen HC, Vuijk PJ, Doyle AE, Kuntsi J. Polygenic association between attention-deficit/hyperactivity disorder liability and cognitive impairments. Psychol Med 2022; 52:3150-3158. [PMID: 33531098 PMCID: PMC9693667 DOI: 10.1017/s0033291720005218] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 07/15/2020] [Accepted: 12/08/2020] [Indexed: 01/11/2023]
Abstract
BACKGROUND A recent genome-wide association study (GWAS) identified 12 independent loci significantly associated with attention-deficit/hyperactivity disorder (ADHD). Polygenic risk scores (PRS), derived from the GWAS, can be used to assess genetic overlap between ADHD and other traits. Using ADHD samples from several international sites, we derived PRS for ADHD from the recent GWAS to test whether genetic variants that contribute to ADHD also influence two cognitive functions that show strong association with ADHD: attention regulation and response inhibition, captured by reaction time variability (RTV) and commission errors (CE). METHODS The discovery GWAS included 19 099 ADHD cases and 34 194 control participants. The combined target sample included 845 people with ADHD (age: 8-40 years). RTV and CE were available from reaction time and response inhibition tasks. ADHD PRS were calculated from the GWAS using a leave-one-study-out approach. Regression analyses were run to investigate whether ADHD PRS were associated with CE and RTV. Results across sites were combined via random effect meta-analyses. RESULTS When combining the studies in meta-analyses, results were significant for RTV (R2 = 0.011, β = 0.088, p = 0.02) but not for CE (R2 = 0.011, β = 0.013, p = 0.732). No significant association was found between ADHD PRS and RTV or CE in any sample individually (p > 0.10). CONCLUSIONS We detected a significant association between PRS for ADHD and RTV (but not CE) in individuals with ADHD, suggesting that common genetic risk variants for ADHD influence attention regulation.
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Affiliation(s)
- Isabella Vainieri
- Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Joanna Martin
- MRC Centre for Neuropsychiatric Genetics & Genomics, School of Medicine, Cardiff University, Cardiff, UK
| | - Anna-Sophie Rommel
- Department of Psychiatry & Department of Environmental Medicine, Public Health at the Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Philip Asherson
- Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Tobias Banaschewski
- Department of Child and Adolescent Psychiatry, Central Institute of Mental Health and Mannheim Medical Faculty, University of Heidelberg, Heidelberg, Germany
| | - Jan Buitelaar
- Karakter Child and Adolescent Psychiatry University Center, Nijmegen, The Netherlands
- Department of Cognitive Neuroscience, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Centre, Nijmegen, The Netherlands
| | - Bru Cormand
- Department of Genetics, Microbiology and Statistics, Faculty of Biology, University of Barcelona, Catalonia, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, Madrid, Spain
- Institut de Biomedicina de la Universitat de Barcelona (IBUB), Barcelona, Catalonia, Spain
- Institut de Recerca Sant Joan de Déu (IR-SJD), Esplugues de Llobregat, Catalonia, Spain
| | - Jennifer Crosbie
- Psychiatry, Neurosciences and Mental Health, The Hospital for Sick Children, University of Toronto, Toronto, Canada
| | - Stephen V. Faraone
- Departments of Psychiatry and Neuroscience and Physiology, SUNY Upstate Medical University, Syracuse, New York, USA
| | - Barbara Franke
- Departments of Human Genetics and Psychiatry, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Centre, Nijmegen, The Netherlands
| | - Sandra K. Loo
- Department of Psychiatry and Biobehavioral Sciences, Semel Institute for Neuroscience and Human Behavior and David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Ana Miranda
- Department of Developmental and Educational Psychology, University of Valencia, Valencia, Spain
| | - Iris Manor
- Geha Mental Health Center, Petah Tikva, Sackler School of Medicine, Tel-Aviv University, Tel-Aviv, Israel
| | - Robert D. Oades
- Department of Child and Adolescent Psychiatry and Psychotherapy, University of Duisburg-Essen, Essen, Germany
| | - Kirstin L. Purves
- Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - J. Antoni Ramos-Quiroga
- Department of Psychiatry, Hospital Universitari Vall d'Hebron, Barcelona, Catalonia, Spain
- Group of Psychiatry, Mental Health and Addictions, Vall d'Hebron Research Institute (VHIR), Barcelona, Catalonia, Spain
- Biomedical Network Research Centre on Mental Health (CIBERSAM), Barcelona, Catalonia, Spain
- Department of Psychiatry and Forensic Medicine, Universitat Autònoma de Barcelona, Barcelona, Catalonia, Spain
| | - Marta Ribasés
- Department of Psychiatry, Hospital Universitari Vall d'Hebron, Barcelona, Catalonia, Spain
- Group of Psychiatry, Mental Health and Addictions, Vall d'Hebron Research Institute (VHIR), Barcelona, Catalonia, Spain
- Biomedical Network Research Centre on Mental Health (CIBERSAM), Barcelona, Catalonia, Spain
- Department of Genetics, Microbiology, and Statistics, Faculty of Biology, University of Barcelona, Catalonia, Spain
| | - Herbert Roeyers
- Department of Experimental Clinical and Health Psychology, Ghent University, Gent, Belgium
| | - Aribert Rothenberger
- Department of Child and Adolescent Psychiatry and Psychotherapy, University Medical Center Göttingen, Goettingen, Germany
| | - Russell Schachar
- Psychiatry, Neurosciences and Mental Health, The Hospital for Sick Children, University of Toronto, Toronto, Canada
| | - Joseph Sergeant
- Department of Clinical Neuropsychology, Vrije Universiteit, Amsterdam, The Netherlands
| | - Hans-Christoph Steinhausen
- Department of Child and Adolescent Psychiatry, University of Zurich, Zurich, Switzerland
- Clinical Psychology and Epidemiology, Institute of Psychology, University of Basel, Basel, Switzerland
- Department of Child and Adolescent Psychiatry, University of Southern Denmark, Odense, Denmark
- Centre of Child and Adolescent Mental Health, Capital Region Psychiatry, Copenhagen, Denmark
| | - Pieter J. Vuijk
- Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, USA
| | - Alysa E. Doyle
- Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Jonna Kuntsi
- Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
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5
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Cañigueral R, Palmer J, Ashwood KL, Azadi B, Asherson P, Bolton PF, McLoughlin G, Tye C. Alpha oscillatory activity during attentional control in children with Autism Spectrum Disorder (ASD), Attention-Deficit/Hyperactivity Disorder (ADHD), and ASD+ADHD. J Child Psychol Psychiatry 2022; 63:745-761. [PMID: 34477232 DOI: 10.1111/jcpp.13514] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 08/13/2021] [Indexed: 12/01/2022]
Abstract
BACKGROUND Autism Spectrum Disorder (ASD) and Attention-Deficit/Hyperactivity Disorder (ADHD) share impairments in top-down and bottom-up modulation of attention. However, it is not yet well understood if co-occurrence of ASD and ADHD reflects a distinct or additive profile of attention deficits. We aimed to characterise alpha oscillatory activity (stimulus-locked alpha desynchronisation and prestimulus alpha) as an index of integration of top-down and bottom-up attentional processes in ASD and ADHD. METHODS Children with ASD, ADHD, comorbid ASD+ADHD, and typically-developing children completed a fixed-choice reaction-time task ('Fast task') while neurophysiological activity was recorded. Outcome measures were derived from source-decomposed neurophysiological data. Main measures of interest were prestimulus alpha power and alpha desynchronisation (difference between poststimulus and prestimulus alpha). Poststimulus activity linked to attention allocation (P1, P3), attentional control (N2), and cognitive control (theta synchronisation, 100-600 ms) was also examined. ANOVA was used to test differences across diagnostics groups on these measures. Spearman's correlations were used to investigate the relationship between attentional control processes (alpha oscillations), central executive functions (theta synchronisation), early visual processing (P1), and behavioural performance. RESULTS Children with ADHD (ADHD and ASD+ADHD) showed attenuated alpha desynchronisation, indicating poor integration of top-down and bottom-up attentional processes. Children with ADHD showed reduced N2 and P3 amplitudes, while children with ASD (ASD and ASD+ADHD) showed greater N2 amplitude, indicating atypical attentional control and attention allocation across ASD and ADHD. In the ASD group, prestimulus alpha and theta synchronisation were negatively correlated, and alpha desynchronisation and theta synchronisation were positively correlated, suggesting an atypical association between attentional control processes and executive functions. CONCLUSIONS ASD and ADHD are associated with disorder-specific impairments, while children with ASD+ADHD overall presented an additive profile with attentional deficits of both disorders. Importantly, these findings may inform the improvement of transdiagnostic procedures and optimisation of personalised intervention approaches.
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Affiliation(s)
- Roser Cañigueral
- Department of Clinical, Educational and Health Psychology, University College London, London, UK
| | - Jason Palmer
- Department of Neurological Diagnosis and Restoration, Osaka University Graduate School of Medicine, CoMIT, Suita, Japan.,Institute for Neural Computation, Univeristy of California San Diego, La Jolla, CA, USA
| | - Karen L Ashwood
- Department of Forensic and Neurodevelopmental Sciences, King's College London, London, UK
| | - Bahar Azadi
- Department of Child & Adolescent Psychiatry, King's College London, London, UK
| | - Philip Asherson
- MRC Social, Genetic and Developmental Psychiatry Centre, King's College London, London, UK
| | - Patrick F Bolton
- Department of Child & Adolescent Psychiatry, King's College London, London, UK.,MRC Social, Genetic and Developmental Psychiatry Centre, King's College London, London, UK
| | - Gráinne McLoughlin
- MRC Social, Genetic and Developmental Psychiatry Centre, King's College London, London, UK
| | - Charlotte Tye
- Department of Child & Adolescent Psychiatry, King's College London, London, UK.,MRC Social, Genetic and Developmental Psychiatry Centre, King's College London, London, UK
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6
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Weiss H, Luciana M. Neurobehavioral maturation of motor response inhibition in adolescence - A narrative review. Neurosci Biobehav Rev 2022; 137:104646. [PMID: 35367223 DOI: 10.1016/j.neubiorev.2022.104646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Revised: 02/19/2022] [Accepted: 03/28/2022] [Indexed: 11/17/2022]
Abstract
Immature motor response inhibition in adolescence is considered contributory to adolescent risk-taking and externalizing behaviors. We review studies reporting age-related variations in motor response inhibition and MRI measurements from typically-developing adolescents. Reviewed studies measured response inhibition using one of three tasks-the Stop Signal Task, Go/No-Go, and Antisaccade Task. Task reliability appears to be particularly strong for the SST. Across tasks and study designs, results indicate that inhibitory control improves markedly through early adolescence. The trajectory of change in later adolescence and into young adulthood (i.e., linear or plateauing) varies depending on the task design. Neuroimaging studies identify adult-like response inhibition networks that are involved in behavioral development. The pros and cons of each task are discussed, including recommendations to guide future studies. Ongoing studies in large longitudinal datasets offer opportunities for further exploration of the shape of change in response inhibition, related neural regions, and associations with other affective and cognitive processes to identify potential impacts of motor response inhibition immaturities or individual differences on adolescent risk-taking behaviors.
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Affiliation(s)
- Hannah Weiss
- Department of Psychology, University of Minnesota, Minneapolis, USA.
| | - Monica Luciana
- Department of Psychology, University of Minnesota, Minneapolis, USA
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7
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Abstract
OBJECTIVE We aimed to understand the association between MW frequency and clinical measures, context regulation of MW and group differences in task performance. METHOD 27 adults with ADHD and 29 controls performed tasks manipulating demand on working memory and sustained attention, and recorded their MW frequency using probes. RESULTS A significant association between MW frequency and the clinical measures was demonstrated. Along with increased MW frequency, individuals with ADHD reported decreasing MW frequency during increasing demands on working memory (context regulation), but not on sustained attention (deficient context regulation). Controls, however, maintained continuous task focus across all conditions. Group differences in task performance were no longer significant after adding MW frequency as a covariate. CONCLUSION Deficient context regulation during increasing demands on sustained attention suggests that sustained attention deficits may play a more important role in regulation of MW in ADHD. MW frequency might also underpin performance deficits in ADHD.
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Affiliation(s)
- Natali Bozhilova
- King’s College London, De
Crespigny Park, UK,Natali Bozhilova, Social, Genetic
and Developmental Psychiatry Centre, Institute of Psychiatry,
Psychology and Neuroscience, King’s College London, De Crespigny Park,
London SE5 8AF, UK.
| | - Giorgia Michelini
- King’s College London, De
Crespigny Park, UK,University of California Los
Angeles, USA
| | | | | | - Katya Rubia
- King’s College London, De
Crespigny Park, UK
| | - Philip Asherson
- King’s College London, De
Crespigny Park, UK,Natali Bozhilova, Social, Genetic
and Developmental Psychiatry Centre, Institute of Psychiatry,
Psychology and Neuroscience, King’s College London, De Crespigny Park,
London SE5 8AF, UK.
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8
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Adamo N, Michelini G, Cheung CHM, Buitelaar JK, Asherson P, Rijsdijk F, Kuntsi J. Does Co-Occurring Anxiety Modulate ADHD-Related Cognitive and Neurophysiological Impairments? J Atten Disord 2021; 25:1135-1145. [PMID: 31711346 DOI: 10.1177/1087054719879499] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Objective: This study investigates whether anxiety modulates cognitive-performance, electrophysiological and electrodermal processes that we previously found impaired in individuals with ADHD. Method: Self-reported anxiety symptoms, cognitive-electrophysiological measures of response inhibition, working memory, attention, conflict monitoring, error processing, and peripheral arousal during three cognitive tasks were obtained from 87 adolescents and young adults with ADHD and 169 controls. We tested the association of anxiety symptoms with each measure and whether controlling for anxiety symptoms attenuates the ADHD-control difference for each measure. Results: Individuals with ADHD showed significantly elevated anxiety symptoms compared with controls. Only commission errors on a Continuous Performance Test (measuring response inhibition) were significantly associated with anxiety symptoms and only among controls, with the ADHD-control difference in this measure remaining significant. Conclusion: Using a wide range of cognitive, electrophysiological, and electrodermal measures, our investigation suggests, overall, limited malleability of these impairments in individuals with ADHD irrespective of their levels of anxiety.
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Affiliation(s)
| | | | | | - Jan K Buitelaar
- Radboud University Medical Center, Nijmegen, The Netherlands.,Karakter Child and Adolescent Psychiatry University Center, Nijmegen, The Netherlands
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9
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Behavioural Measures of Infant Activity but Not Attention Associate with Later Preschool ADHD Traits. Brain Sci 2021; 11:brainsci11050524. [PMID: 33919004 PMCID: PMC8143002 DOI: 10.3390/brainsci11050524] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 03/15/2021] [Accepted: 03/18/2021] [Indexed: 11/16/2022] Open
Abstract
Mapping infant neurocognitive differences that precede later ADHD-related behaviours is critical for designing early interventions. In this study, we investigated (1) group differences in a battery of measures assessing aspects of attention and activity level in infants with and without a family history of ADHD or related conditions (ASD), and (2) longitudinal associations between the infant measures and preschool ADHD traits at 3 years. Participants (N = 151) were infants with or without an elevated likelihood for ADHD (due to a family history of ADHD and/or ASD). A multi-method assessment protocol was used to assess infant attention and activity level at 10 months of age that included behavioural, cognitive, physiological and neural measures. Preschool ADHD traits were measured at 3 years of age using the Child Behaviour Checklist (CBCL) and the Child Behaviour Questionnaire (CBQ). Across a broad range of measures, we found no significant group differences in attention or activity level at 10 months between infants with and without a family history of ADHD or ASD. However, parent and observer ratings of infant activity level at 10 months were positively associated with later preschool ADHD traits at 3 years. Observable behavioural differences in activity level (but not attention) may be apparent from infancy in children who later develop elevated preschool ADHD traits.
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10
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Streimann K, Sisask M, Toros K. Children’s mental health in different contexts: Results from a multi-informant assessment of Estonian first-grade students. SCHOOL PSYCHOLOGY INTERNATIONAL 2021. [DOI: 10.1177/01430343211000414] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The current study sought to investigate the agreement between teachers and parents about the mental health of first-grade students, the factors that affected this agreement and the associations between measures completed by students, parents and teachers. The investigation used baseline data collected during the PAX Good Behavior Game (PAX GBG) effectiveness study in 42 Estonian schools (N = 708). Information was collected about externalizing and internalizing difficulties and prosocial behaviour, and about inhibitory control. Our research showed higher agreement between parents and teachers about externalizing behaviour and lower agreement regarding prosocial behavior and emotional problems. Inhibition was correlated with teacher-rated questionnaires, but not with parents’ responses. Sociodemographic factors influenced the agreement between teachers and parents somewhat differently. This study highlights the importance of a multi-informant approach in students’ mental health assessments, as some problems might be less observable in certain environments or by some respondents. The practical implications of these findings are discussed and suggestions are provided for the development of a school-based mental health screening system.
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Affiliation(s)
- Karin Streimann
- National Institute for Health Development, Tallinn, Estonia
- School of Governance, Law and Society, Tallinn University, Tallinn, Estonia
- School of Governance, Law and Society, Tallinn University, Tallinn, Estonia
| | - Merike Sisask
- School of Governance, Law and Society, Tallinn University, Tallinn, Estonia
- Estonian-Swedish Mental Health and Suicidology Institute, Tallinn, Estonia
- School of Governance, Law and Society, Tallinn University, Tallinn, Estonia
| | - Karmen Toros
- School of Governance, Law and Society, Tallinn University, Tallinn, Estonia
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11
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Karalunas SL, Bierman K, Huang-Pollock CL. Test-Retest Reliability and Measurement Invariance of Executive Function Tasks in Young Children With and Without ADHD. J Atten Disord 2020; 24:1891-1904. [PMID: 26861156 PMCID: PMC4980280 DOI: 10.1177/1087054715627488] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Objective: Measurement reliability is assumed when executive function (EF) tasks are used to compare groups or to examine relationships between cognition and etiologic and maintaining factors of psychiatric disorders. However, the test-retest reliabilities of many commonly used EF tasks have rarely been examined in young children. Furthermore, measurement invariance between typically developing and psychiatric populations has not been examined. Method: Test-retest reliability of a battery of commonly used EF tasks was assessed in a group of children between the ages of 5 and 6 years old with (n = 63) and without (n = 44) ADHD. Results: Few individual tasks achieved adequate reliability. However, confirmatory factor analysis (CFA) models identified two factors, working memory and inhibition, with test-retest correlations approaching 1.0. Multiple indicators multiple causes (MIMIC) models confirmed configural measurement invariance between the groups. Conclusion: Problems created by poor reliability, including reduced power to detect group differences, index change over time, or to identify relationships with other measures, may be mitigated using latent variable approaches.
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Affiliation(s)
| | - Karen Bierman
- The Pennsylvania State University, Department of
Psychology
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12
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Adamo N, Hodsoll J, Asherson P, Buitelaar JK, Kuntsi J. Ex-Gaussian, Frequency and Reward Analyses Reveal Specificity of Reaction Time Fluctuations to ADHD and Not Autism Traits. JOURNAL OF ABNORMAL CHILD PSYCHOLOGY 2020; 47:557-567. [PMID: 30027330 PMCID: PMC6397137 DOI: 10.1007/s10802-018-0457-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Both attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) have been linked to increased reaction time variability (RTV), a marker of attentional fluctuation. Here we test whether specificity to either trait emerges when we examine (1) detailed ex-Gaussian and frequency RTV subcomponents, (2) effects while controlling for the other trait and (3) improvement in the RTV measures following rewards or a faster event rate. 1110 children aged 7-10 years from a population-based sample completed a Go/No-Go task under three conditions (slow, fast and incentives). We measured RTV with standard deviation of RT (SDRT), ex-Gaussian distribution measures (Sigma and Tau), RT fluctuations in cycles of ~14-90 s in all conditions (Slow-4 and Slow-5), and RT fluctuations in cycles of 2-14 s in the fast condition (Slow-2 and Slow-3). Parent-rated ADHD and ASD traits were obtained. All refined RTV components were linked to ADHD traits only and not to ASD traits, while Sigma did not relate to either trait. Although both ADHD and ASD social-communication traits were associated with SDRT, the association with social-communication impairments disappeared when controlling for ADHD traits. A reward-induced improvement in RTV measures, indicating malleability, emerged in relation to ADHD traits but not ASD traits. Under closer inspection, specificity emerges of high RTV to ADHD traits. For the clinician, our findings indicate that attentional fluctuation in children with high ASD traits may be due to co-occurring ADHD traits and emphasise how the effectiveness of rewards does not generalise from ADHD to ASD traits.
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Affiliation(s)
- Nicoletta Adamo
- Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology and Neuroscience, King's College London, De Crespigny Park (PO80), London, SE5 8AF, UK
| | - John Hodsoll
- Department of Biostatistics & Health Informatics, Institute of Psychiatry, Psychology and Neuroscience, King's College London, De Crespigny Park (PO20), London, SE5 8AF, UK
| | - Philip Asherson
- Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology and Neuroscience, King's College London, De Crespigny Park (PO80), London, SE5 8AF, UK
| | - Jan K Buitelaar
- Department of Cognitive Neuroscience, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Centre, Trigon building, Route 200, Kapittelweg 29, 6525 EN, Nijmegen, The Netherlands
| | - Jonna Kuntsi
- Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology and Neuroscience, King's College London, De Crespigny Park (PO80), London, SE5 8AF, UK.
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Helfer B, Maltezos S, Liddle E, Kuntsi J, Asherson P. Lateralization of attention in adults with ADHD: Evidence of pseudoneglect. Eur Psychiatry 2020; 63:e68. [PMID: 32594941 PMCID: PMC7443776 DOI: 10.1192/j.eurpsy.2020.68] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Background. We investigated whether adults with attention-deficit/hyperactivity disorder (ADHD) show pseudoneglect—preferential allocation of attention to the left visual field (LVF) and a resulting slowing of mean reaction times (MRTs) in the right visual field (RVF), characteristic of neurotypical (NT) individuals —and whether lateralization of attention is modulated by presentation speed and incentives. Method. Fast Task, a four-choice reaction-time task where stimuli were presented in LVF or RVF, was used to investigate differences in MRT and reaction time variability (RTV) in adults with ADHD (n = 43) and NT adults (n = 46) between a slow/no-incentive and fast/incentive condition. In the lateralization analyses, pseudoneglect was assessed based on MRT, which was calculated separately for the LVF and RVF for each condition and each study participant. Results. Adults with ADHD had overall slower MRT and increased RTV relative to NT. MRT and RTV improved under the fast/incentive condition. Both groups showed RVF-slowing with no between-group or between-conditions differences in RVF-slowing. Conclusion. Adults with ADHD exhibited pseudoneglect, a NT pattern of lateralization of attention, which was not attenuated by presentation speed and incentives.
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Affiliation(s)
- Bartosz Helfer
- National Heart and Lung Institute, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Stefanos Maltezos
- Department of Forensic and Neurodevelopmental Science, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom.,Adult Autism and ADHD Service, South London and Maudsley NHS Foundation Trust, London, United Kingdom
| | - Elizabeth Liddle
- Division of Psychiatry and Applied Psychology, Institute of Mental Health, Faculty of Medicine & Health Sciences, University of Nottingham, United Kingdom
| | - Jonna Kuntsi
- Social Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
| | - Philip Asherson
- Social Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
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14
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James SN, Rommel AS, Rijsdijk F, Michelini G, McLoughlin G, Brandeis D, Banaschewski T, Asherson P, Kuntsi J. Is association of preterm birth with cognitive-neurophysiological impairments and ADHD symptoms consistent with a causal inference or due to familial confounds? Psychol Med 2020; 50:1278-1284. [PMID: 31155011 PMCID: PMC7322548 DOI: 10.1017/s0033291719001211] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Revised: 05/03/2019] [Accepted: 05/08/2019] [Indexed: 11/22/2022]
Abstract
BACKGROUND Preterm birth is associated with an increased risk for cognitive-neurophysiological impairments and attention-deficit/hyperactivity disorder (ADHD). Whether the associations are due to the preterm birth insult per se, or due to other risk factors that characterise families with preterm-born children, is largely unknown. METHODS We employed a within-sibling comparison design, using cognitive-performance and event-related potential (ERP) measures from 104 preterm-born adolescents and 104 of their term-born siblings. Analyses focused on ADHD symptoms and cognitive and ERP measures from a cued continuous performance test, an arrow flanker task and a reaction time task. RESULTS Within-sibling analyses showed that preterm birth was significantly associated with increased ADHD symptoms (β = 0.32, p = 0.01, 95% CI 0.05 to 0.58) and specific cognitive-ERP impairments, such as IQ (β = -0.20, p = 0.02, 95% CI -0.40 to -0.01), preparation-vigilance measures and measures of error processing (ranging from β = 0.71, -0.35). There was a negligible within-sibling association between preterm birth with executive control measures of inhibition (NoGo-P3, β = -0.07, p = 0.45, 95% CI -0.33 to 0.15) or verbal working memory (digit span backward, β = -0.05, p = 0.63, 95% CI -0.30 to 0.18). CONCLUSIONS Our results suggest that the relationship between preterm birth with ADHD symptoms and specific cognitive-neurophysiological impairments (IQ, preparation-vigilance and error processing) is independent of family-level risk and consistent with a causal inference. In contrast, our results suggest that previously observed associations between preterm birth with executive control processes of inhibition and working memory are instead linked to background characteristics of families with a preterm-born child rather than preterm birth insult per se. These findings suggest that interventions need to target both preterm-birth specific and family-level risk factors.
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Affiliation(s)
- Sarah-Naomi James
- King's College London, Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology and Neuroscience, De Crespigny Park, London, UK
- MRC Lifelong Health and Ageing Unit at UCL, University College London, London, UK
| | - Anna-Sophie Rommel
- King's College London, Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology and Neuroscience, De Crespigny Park, London, UK
| | - Fruhling Rijsdijk
- King's College London, Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology and Neuroscience, De Crespigny Park, London, UK
| | - Giorgia Michelini
- King's College London, Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology and Neuroscience, De Crespigny Park, London, UK
| | - Gráinne McLoughlin
- King's College London, Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology and Neuroscience, De Crespigny Park, London, UK
| | - Daniel Brandeis
- Department of Child and Adolescent Psychiatry and Psychotherapy, Central Institute of Mental Health, Medical Faculty Mannheim/Heidelberg University, Mannheim, Germany
- Department of Child and Adolescent Psychiatry and Psychotherapy, Psychiatric Hospital, University of Zurich, Zurich, Switzerland
- Center for Integrative Human Physiology, University of Zurich, Zurich, Switzerland
- Neuroscience Center Zurich, University of Zurich, Zurich, Switzerland
| | - Tobias Banaschewski
- Department of Child and Adolescent Psychiatry and Psychotherapy, Central Institute of Mental Health, Medical Faculty Mannheim/Heidelberg University, Mannheim, Germany
| | - Philip Asherson
- King's College London, Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology and Neuroscience, De Crespigny Park, London, UK
| | - Jonna Kuntsi
- King's College London, Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology and Neuroscience, De Crespigny Park, London, UK
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15
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Friso-van den Bos I, van de Weijer-Bergsma E. Classroom versus individual working memory assessment: predicting academic achievement and the role of attention and response inhibition. Memory 2019; 28:70-82. [PMID: 31645187 DOI: 10.1080/09658211.2019.1682170] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Working memory (WM) is an important predictor for academic learning and achievement. Typically, children's WM is assessed in controlled testing situations, which might not reflect functioning in typical classroom learning situations with natural distractions. In this study, we compared WM performance in controlled and classroom situations and their predictive value for academic achievement. Also, we examined whether performance differences between situations were moderated by attention or response inhibition. In a within-subjects design, primary school children completed visuospatial and verbal WM tasks in two settings (classroom versus controlled individual setting). First, WM functioning was lower in the classroom setting. Second, attention moderated individual differences in this discrepancy between settings, but response inhibition did not. Third, classroom obtained verbal WM scores were the strongest predictors of academic achievement. Our results indicate that classroom assessment of verbal WM provides a more ecologically valid measurement of WM abilities in a real-life learning situation.
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Affiliation(s)
- Ilona Friso-van den Bos
- Department of Pedagogical and Educational Sciences, Faculty of Social and Behavioural Sciences, Utrecht University, Utrecht, Netherlands.,Department of Educational Sciences, Faculty of Behavioural and Management Sciences, University of Twente
| | - Eva van de Weijer-Bergsma
- Department of Pedagogical and Educational Sciences, Faculty of Social and Behavioural Sciences, Utrecht University, Utrecht, Netherlands
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16
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Minder F, Zuberer A, Brandeis D, Drechsler R. Specific Effects of Individualized Cognitive Training in Children with Attention-Deficit/Hyperactivity Disorder (ADHD): The Role of Pre-Training Cognitive Impairment and Individual Training Performance. Dev Neurorehabil 2019; 22:400-414. [PMID: 31021250 DOI: 10.1080/17518423.2019.1600064] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Objective: We investigated the impact of the pre-training neuropsychological (NP) impairment and of the training progress on the NP and behavioural outcome after computerized cognitive training (CogT) in children with ADHD. Method: Thirty-one participants underwent individualized CogT (focussing on one or two cognitive domains: working memory, inhibition, attention) over 12 weeks. NP tests and behaviour ratings served as outcome measures. Results: After CogT, significant improvements emerged according to parents' ratings, but only on very few NP test measures. Children with milder/no pre-training NP impairment showed larger improvements on behavioural ratings than more impaired children. A steeper training performance slope was related to better behavioural outcomes. Conclusion: We find partial support for specific effects of CogT, but the assumption that an individually tailored selection of training tasks would be particularly beneficial for children with ADHD with NP deficits was not confirmed. Trial registration number: NCT02358941.
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Affiliation(s)
- Franziska Minder
- a Department of Child and Adolescent Psychiatry and Psychotherapy , University Hospital of Psychiatry, University of Zurich , Zurich , Switzerland
| | - Agnieszka Zuberer
- a Department of Child and Adolescent Psychiatry and Psychotherapy , University Hospital of Psychiatry, University of Zurich , Zurich , Switzerland
| | - Daniel Brandeis
- a Department of Child and Adolescent Psychiatry and Psychotherapy , University Hospital of Psychiatry, University of Zurich , Zurich , Switzerland.,b Neuroscience Center Zurich , University of Zurich and ETH Zurich , Zurich , Switzerland.,c Department of Child and Adolescent Psychiatry and Psychotherapy, Central Institute of Mental Health , Medical Faculty Mannheim/Heidelberg University , Mannheim , Germany.,d Center for Integrative Human Physiology , University of Zurich , Zurich , Switzerland
| | - Renate Drechsler
- a Department of Child and Adolescent Psychiatry and Psychotherapy , University Hospital of Psychiatry, University of Zurich , Zurich , Switzerland
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17
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Singing to the self: Children’s private speech, private song, and executive functioning. COGNITIVE DEVELOPMENT 2019. [DOI: 10.1016/j.cogdev.2019.04.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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18
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Lau-Zhu A, Fritz A, McLoughlin G. Overlaps and distinctions between attention deficit/hyperactivity disorder and autism spectrum disorder in young adulthood: Systematic review and guiding framework for EEG-imaging research. Neurosci Biobehav Rev 2019; 96:93-115. [PMID: 30367918 PMCID: PMC6331660 DOI: 10.1016/j.neubiorev.2018.10.009] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 06/08/2018] [Accepted: 10/18/2018] [Indexed: 11/20/2022]
Abstract
Attention deficit/hyperactivity disorders (ADHD) and autism spectrum disorders (ASD) frequently co-occur. However, we know little about the neural basis of the overlaps and distinctions between these disorders, particularly in young adulthood - a critical time window for brain plasticity across executive and socioemotional domains. Here, we systematically review 75 articles investigating ADHD and ASD in young adult samples (mean ages 16-26) using cognitive tasks, with neural activity concurrently measured via electroencephalography (EEG) - the most accessible neuroimaging technology. The majority of studies focused on event-related potentials (ERPs), with some beginning to capitalise on oscillatory approaches. Overlapping and specific profiles for ASD and ADHD were found mainly for four neurocognitive domains: attention processing, performance monitoring, face processing and sensory processing. No studies in this age group directly compared both disorders or considered dual diagnosis with both disorders. Moving forward, understanding of ADHD, ASD and their overlap in young adulthood would benefit from an increased focus on cross-disorder comparisons, using similar paradigms and in well-powered samples and longitudinal cohorts.
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Affiliation(s)
- Alex Lau-Zhu
- Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom.
| | - Anne Fritz
- Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
| | - Gráinne McLoughlin
- Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
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Lukito S, Jones CRG, Pickles A, Baird G, Happé F, Charman T, Simonoff E. Specificity of executive function and theory of mind performance in relation to attention-deficit/hyperactivity symptoms in autism spectrum disorders. Mol Autism 2017; 8:60. [PMID: 29152165 PMCID: PMC5680830 DOI: 10.1186/s13229-017-0177-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Accepted: 10/31/2017] [Indexed: 01/17/2023] Open
Abstract
Background Individuals with autism spectrum disorder (ASD) frequently demonstrate symptoms of attention-deficit/hyperactivity disorder (ADHD). Previous findings in children with ASD have suggested that these symptoms are associated with an impairment in executive function (EF) abilities. However, studies rarely considered this association within a single framework that controls for other related factors such as Theory of Mind (ToM) abilities and ASD symptoms. Methods We used structural equation modeling to explore the relations among EF, ToM, and symptoms of ASD and ADHD, using data from a population-based sample of 100 adolescents with ASD and full-scale IQ ≥ 50 (the Special Needs and Autism Project (SNAP) cohort). The study used a multi-measure and multi-informant approach, where performance of inhibition, planning, switching, and working memory tasks indexed EF and performance on tasks involving mentalizing indexed ToM. Measures of ASD and ADHD symptoms included parent and teacher reports and direct observation of the children. Shared source of symptom reporting was accounted for with a parental rating latent factor indexed by symptom measures reported by parents. Results Impairments in EF abilities were specifically associated with ADHD symptoms while impaired ToM was specifically associated with ASD symptoms, when accounting for the associations of each cognitive domain with the other factors. ASD and ADHD symptom latent factors were also correlated, but this association became nonsignificant once the shared source of reporting from parents was accounted for and within a model that also controlled for the correlated pathway between EF and ToM factors. The specific relations between the cognitive domains and behavioral symptoms remained even after controlling for IQ. Conclusions In this ASD sample, symptoms of ADHD and ASD are underpinned by separate cognitive domains. The association between EF and ToM impairments is a likely partial explanation for the co-occurrence of ADHD symptoms in ASD, but the role of shared reporting effects is also important and supports the inclusion of independent informants and objective measures in future research.
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Affiliation(s)
- Steve Lukito
- Department of Child and Adolescent Psychiatry, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | | | - Andrew Pickles
- Department of Biostatistics and Biomedical Research Centre for Mental Health, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Gillian Baird
- Guy's and St Thomas' NHS Foundation Trust, King's Health Partners, London, UK
| | - Francesca Happé
- Institute of Psychiatry, Social, Genetic and Developmental Psychiatry (SGDP) Centre, Psychology and Neuroscience, King's College London, London, UK
| | - Tony Charman
- Department of Psychology, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Emily Simonoff
- Department of Child and Adolescent Psychiatry, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
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20
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Fitzpatrick CM, Maric VS, Bate ST, Andreasen JT. Influence of intertrial interval on basal and drug-induced impulsive action in the 5-choice serial reaction time task: Effects of d-amphetamine and (±)-2,5-dimethoxy-4-iodoamphetamine (DOI). Neurosci Lett 2017; 662:351-355. [PMID: 29102783 DOI: 10.1016/j.neulet.2017.10.058] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2017] [Revised: 10/25/2017] [Accepted: 10/28/2017] [Indexed: 01/17/2023]
Abstract
Impulsivity is a characteristic of a number of neuropsychiatric disorders such as attention-deficit/hyperactivity disorder. The 5-choice serial reaction time task (5-CSRTT) is a rodent paradigm extensively used to assess attention and impulsivity. Notably, 5-CSRTT studies do not typically account for the reduction in premature responding, the measure of impulsive action, occurring upon repeated exposure to test sessions with long or variable intertrial intervals (ITIs). This present 5-CSRTT study investigated the use of variable ITIs (5, 10 or 15s) across 15 test days (4 training days followed by 1 drug test day per week for three weeks) as previous experience had shown that 4 training days would be sufficient to induce consistent premature response levels in male C57BL/6J mice. Once a steady state was achieved, the effects of dextroamphetamine (AMPH) and (±)-2,5-dimethoxy-4-iodoamphetamine (DOI) were then assessed using a Latin-square design to determine whether pharmacological-induced impulsive actions depended on ITI length. Mice habituated to the variable ITI schedule after only 3days and showed consistently lower premature response levels until the end of the study. AMPH (p<0.05) and DOI (p<0.05) increased the percentage of premature responses at 15s ITI trials, while only DOI (p<0.05) increased impulsive action at 10s ITI trials. Additionally, DOI increased omission rates (p<0.001), mean correct latency (p<0.01), reward collection latency (p<0.001), and reduced the total attempted trials (p<0.001). In summary, we demonstrated that mice habituate to the variable ITI schedule, suggesting that using the variable ITI schedule during training allowed premature response rates to stabilize before commencing pharmacological testing. Moreover, in these habituated mice AMPH and DOI significantly enhanced impulsive action at the long ITI trials only. We propose that experimental design considerations can improve the sensitivity of the 5-CSRTT to detect pharmacologicallyinduced impulsive action.
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Affiliation(s)
- Ciaràn M Fitzpatrick
- Department of Drug Design and Pharmacology, University of Copenhagen, Universitetsparken 2, DK-2100, Copenhagen, Denmark.
| | | | - Simon T Bate
- Statistical Sciences, GlaxoSmithKline, Medicines Research Centre, Gunnels Wood Road, Stevenage, Hertfordshire, SG1 2NY, UK
| | - Jesper T Andreasen
- Department of Drug Design and Pharmacology, University of Copenhagen, Universitetsparken 2, DK-2100, Copenhagen, Denmark
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21
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Liu ZZ, Qu HJ, Tian ZL, Han MJ, Fan Y, Ge LZ, Zang YF, Zhang H. Reproducibility of frequency-dependent low frequency fluctuations in reaction time over time and across tasks. PLoS One 2017; 12:e0184476. [PMID: 28910331 PMCID: PMC5598978 DOI: 10.1371/journal.pone.0184476] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2016] [Accepted: 08/21/2017] [Indexed: 11/19/2022] Open
Abstract
Objective Increased levels of reaction time variability (RTV) are characteristics of sustained attention deficits. The clinical significance of RTV has been widely recognized. However, the reliability of RTV measurements has not been widely studied. The present study aimed to assess the test-retest reliability of RTV conventional measurements, e.g., the standard deviation (SD), the coefficient of variation (CV), and a new measurement called the amplitude of low frequency fluctuation (ALFF) of RT. In addition, we aimed to assess differences and similarities of these measurements between different tasks. Method Thirty-seven healthy college students participated in 2 tasks, i.e., an Eriksen flanker task (EFT) and a simple reaction task (SRT), twice over a mean interval of 56 days. Conventional measurements of RTV including RT-SD and RT-CV were assessed first. Then the RT time series were converted into frequency domains, and RT-ALFF was further calculated for the whole frequency band (0.0023–0.167 Hz) and for a few sub-frequency bands including Slow-6 (<0.01 Hz), Slow-5 (0.01–0.027 Hz), Slow-4 (0.027–0.073 Hz), and Slow-3 (0.073–0.167 Hz). The test-retest reliability of these measurements was evaluated through intra-class correlation (ICC) tests. Differences and correlations between each EFT and SRT measurement were further examined during both visits. Results 1) The RT-ALFF of the Slow-5/4/3 and conventional measurements of RT-SD and RT-CV showed moderate to high levels of test-retest reliability. EFT RT-ALFF patterns generated slightly higher ICC values than SRT values in higher frequency bands (Slow-3), but SRT RT-ALFF values showed slightly higher ICC values than EFT values in lower frequency bands (Slow-5 and Slow-4). 2) RT-ALFF magnitudes in each sub-frequency band were greater for the SRT than those for the EFT. 3) The RT-ALFF in the Slow-4 of the EFT was found to be correlated with the RT-ALFF in the Slow-5 of the SRT for both two visits, but no consistently significant correlation was found between the same frequency bands. Conclusions These findings reveal good test-retest reliability for conventional measurements and for the RT-ALFF of RTV. The RT-ALFF presented frequency-dependent similarities across tasks. All of our results reveal the presence of different frequency structures between the two tasks, and thus the frequency-dependent characteristics of different tasks deserve more attention in future studies.
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Affiliation(s)
- Zan-Zan Liu
- Department of Psychology, Zhejiang Sci-Tech University, Hangzhou, China
| | - Hui-Jie Qu
- Department of Psychology, Zhejiang Sci-Tech University, Hangzhou, China
| | - Zhuo-Ling Tian
- Institutes of Psychological Sciences, Hangzhou Normal University, Hangzhou, China
- Zhejiang Key Laboratory for Research in Assessment of Cognitive Impairments, Hangzhou, China
- Center for Cognition and Brain Disorders, Hangzhou Normal University, Hangzhou, China
| | - Meng-Jian Han
- Department of Physics, Zhejiang Sci-Tech University, Hangzhou, China
| | - Yi Fan
- Institutes of Psychological Sciences, Hangzhou Normal University, Hangzhou, China
- Zhejiang Key Laboratory for Research in Assessment of Cognitive Impairments, Hangzhou, China
- Center for Cognition and Brain Disorders, Hangzhou Normal University, Hangzhou, China
| | - Lie-Zhong Ge
- Department of Psychology, Zhejiang Sci-Tech University, Hangzhou, China
| | - Yu-Feng Zang
- Institutes of Psychological Sciences, Hangzhou Normal University, Hangzhou, China
- Zhejiang Key Laboratory for Research in Assessment of Cognitive Impairments, Hangzhou, China
- Center for Cognition and Brain Disorders, Hangzhou Normal University, Hangzhou, China
- * E-mail: (YFZ); (HZ)
| | - Hang Zhang
- Paul C. Lauterbur Research Centers for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
- * E-mail: (YFZ); (HZ)
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22
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Salari R, Bohlin G, Rydell AM, Thorell LB. Neuropsychological Functioning and Attachment Representations in Early School Age as Predictors of ADHD Symptoms in Late Adolescence. Child Psychiatry Hum Dev 2017; 48:370-384. [PMID: 27349655 DOI: 10.1007/s10578-016-0664-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
This study aimed to examine relations between parent and child attachment representations and neuropsychological functions at age 8, as well as relations between these constructs and ADHD symptoms over a 10-year period. A community-based sample of 105 children (52 boys) participated. Measures of attachment representations and a range of neuropsychological functions were collected at age 8. Parents rated emotion dysregulation and ADHD symptoms at age 8 and ADHD symptoms again at age 18. Significant, although modest, relations were found between disorganized attachment and some aspects of neuropsychological functioning in childhood. When studying outcomes in late adolescence and controlling for early ADHD symptom levels, spatial working memory and disorganized attachment remained significant in relation to both ADHD symptom domains, and one measure of inhibition remained significant for hyperactivity/impulsivity. When examining independent effects, spatial working memory and disorganized attachment were related to inattention, whereas spatial working memory and dysregulation of happiness/exuberance were related to hyperactivity/impulsivity. Our findings showing that disorganized attachment is longitudinally related to ADHD symptoms over and above the influence of both neuropsychological functioning and early ADHD symptom levels highlights the importance of including measures of attachment representations when trying to understand the development of ADHD symptoms. If replicated in more "at-risk" samples, these findings could also suggest that parent-child attachment should be taken into consideration when children are referred for assessment and treatment of ADHD.
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Affiliation(s)
- Raziye Salari
- Division of Psychology, Department of Clinical Neuroscience and Stockholm Brain Institute, Karolinska Institutet, Nobels Väg 9, 171 65, Stockholm, Sweden
- Department of Women's and Children's Health, Uppsala University, Uppsala, Sweden
| | - Gunilla Bohlin
- Department of Psychology, Uppsala University, Uppsala, Sweden
| | | | - Lisa B Thorell
- Division of Psychology, Department of Clinical Neuroscience and Stockholm Brain Institute, Karolinska Institutet, Nobels Väg 9, 171 65, Stockholm, Sweden.
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Cheung CHM, McLoughlin G, Brandeis D, Banaschewski T, Asherson P, Kuntsi J. Neurophysiological Correlates of Attentional Fluctuation in Attention-Deficit/Hyperactivity Disorder. Brain Topogr 2017; 30:320-332. [PMID: 28289850 PMCID: PMC5408051 DOI: 10.1007/s10548-017-0554-2] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Accepted: 02/01/2017] [Indexed: 11/25/2022]
Abstract
Cognitive performance in attention-deficit/hyperactivity disorder (ADHD) is characterised, in part, by frequent fluctuations in response speed, resulting in high reaction time variability (RTV). RTV captures a large proportion of the genetic risk in ADHD but, importantly, is malleable, improving significantly in a fast-paced, rewarded task condition. Using the temporal precision offered by event-related potentials (ERPs), we aimed to examine the neurophysiological measures of attention allocation (P3 amplitudes) and preparation (contingent negative variation, CNV), and their associations with the fluctuating RT performance and its improvement in ADHD. 93 participants with ADHD and 174 controls completed the baseline and fast-incentive conditions of a four-choice reaction time task, while EEG was simultaneously recorded. Compared to controls, individuals with ADHD showed both increased RTV and reduced P3 amplitudes during performance on the RT task. In the participants with ADHD, attenuated P3 amplitudes were significantly associated with high RTV, and the increase in P3 amplitudes from a slow baseline to a fast-paced, rewarded condition was significantly associated with the RTV decrease. Yet, the individuals with ADHD did not show the same increase in CNV from baseline to fast-incentive condition as observed in controls. ADHD is associated both with a neurophysiological impairment of attention allocation (P3 amplitudes) and an inability to adjust the preparatory state (CNV) in a changed context. Our findings suggest that both neurophysiological and cognitive performance measures of attention are malleable in ADHD, which are potential targets for non-pharmacological interventions.
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Affiliation(s)
- Celeste H M Cheung
- MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Gráinne McLoughlin
- MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Daniel Brandeis
- Department of Child and Adolescent Psychiatry and Psychotherapy, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany.,Department of Child and Adolescent Psychiatry, University of Zurich, Zurich, Switzerland.,Center for Integrative Human Physiology, University of Zurich, Zurich, Switzerland.,Neuroscience Center Zurich, University of Zurich, Zurich, Switzerland
| | - Tobias Banaschewski
- Department of Child and Adolescent Psychiatry and Psychotherapy, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Philip Asherson
- MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Jonna Kuntsi
- MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK.
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Pinto R, Rijsdijk F, Ronald A, Asherson P, Kuntsi J. The Genetic Overlap of Attention-Deficit/Hyperactivity Disorder and Autistic-like Traits: an Investigation of Individual Symptom Scales and Cognitive markers. JOURNAL OF ABNORMAL CHILD PSYCHOLOGY 2016; 44:335-45. [PMID: 26021462 PMCID: PMC4729813 DOI: 10.1007/s10802-015-0037-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorders (ASDs) frequently co-occur. However, due to previous exclusionary diagnostic criteria, little is known about the underlying causes of this covariation. Twin studies assessing ADHD symptoms and autistic-like traits (ALTs) suggest substantial genetic overlap, but have largely failed to take into account the genetic heterogeneity of symptom subscales. This study aimed to clarify the phenotypic and genetic relations between ADHD and ASD by distinguishing between symptom subscales that characterise the two disorders. Moreover, we aimed to investigate whether ADHD-related cognitive impairments show a relationship with ALT symptom subscales; and whether potential shared cognitive impairments underlie the genetic risk shared between the ADHD and ALT symptoms. Multivariate structural equation modelling was conducted on a population-based sample of 1312 twins aged 7–10. Social-communication ALTs correlated moderately with both ADHD symptom domains (phenotypic correlations around 0.30) and showed substantial genetic overlap with both inattention and hyperactivity-impulsivity (genetic correlation = 0.52 and 0.44, respectively). In addition to previously reported associations with ADHD traits, reaction time variability (RTV) showed significant phenotypic (0.18) and genetic (0.32) association with social-communication ALTs. RTV captured a significant proportion (24 %) of the genetic influences shared between inattention and social-communication ALTs. Our findings suggest that social-communication ALTs underlie the previously observed phenotypic and genetic covariation between ALTs and ADHD symptoms. RTV is not specific to ADHD symptoms, but is also associated with social-communication ALTs and can, in part, contribute to an explanation of the co-occurrence of ASD and ADHD.
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Affiliation(s)
- Rebecca Pinto
- King's College London, MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology, and Neuroscience, De Crespigny Park, SE5 8AF, London, UK
| | - Fruhling Rijsdijk
- King's College London, MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology, and Neuroscience, De Crespigny Park, SE5 8AF, London, UK
| | - Angelica Ronald
- Department of Psychological Sciences, Birkbeck, University of London, London, UK
| | - Philip Asherson
- King's College London, MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology, and Neuroscience, De Crespigny Park, SE5 8AF, London, UK
| | - Jonna Kuntsi
- King's College London, MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology, and Neuroscience, De Crespigny Park, SE5 8AF, London, UK.
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Tye C, Johnson KA, Kelly SP, Asherson P, Kuntsi J, Ashwood KL, Azadi B, Bolton P, McLoughlin G. Response time variability under slow and fast-incentive conditions in children with ASD, ADHD and ASD+ADHD. J Child Psychol Psychiatry 2016; 57:1414-1423. [PMID: 27465225 PMCID: PMC5132150 DOI: 10.1111/jcpp.12608] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/13/2016] [Indexed: 11/29/2022]
Abstract
BACKGROUND Attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) show significant behavioural and genetic overlap. Both ADHD and ASD are characterised by poor performance on a range of cognitive tasks. In particular, increased response time variability (RTV) is a promising indicator of risk for both ADHD and ASD. However, it is not clear whether different indices of RTV and changes to RTV according to task conditions are able to discriminate between the two disorders. METHODS Children with ASD (n = 19), ADHD (n = 18), ASD + ADHD (n = 29) and typically developing controls (TDC; n = 26) performed a four-choice RT task with slow-baseline and fast-incentive conditions. Performance was characterised by mean RT (MRT), standard deviation of RT (SD-RT), coefficient of variation (CV) and ex-Gaussian distribution measures of Mu, Sigma and Tau. RESULTS In the slow-baseline condition, categorical diagnoses and trait measures converged to indicate that children with ADHD-only and ASD + ADHD demonstrated increased MRT, SD-RT, CV and Tau compared to TDC and ASD-only. Importantly, greater improvement in MRT, SD-RT and Tau was demonstrated in ADHD and ASD + ADHD from slow-baseline to fast-incentive conditions compared to TDC and ASD-only. CONCLUSIONS Slower and more variable RTs are markers of ADHD compared to ASD and typically developing controls during slow and less rewarding conditions. Energetic factors and rewards improve task performance to a greater extent in children with ADHD compared to children with ASD. These findings suggest that RTV can be distinguished in ASD, ADHD and ASD + ADHD based on the indices of variability used and the conditions in which they are elicited. Further work identifying neural processes underlying increased RTV is warranted, in order to elucidate disorder-specific and disorder-convergent aetiological pathways.
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Affiliation(s)
- Charlotte Tye
- King's College LondonMRC Social Genetic and Developmental Psychiatry CentreInstitute of Psychiatry, Psychology & NeuroscienceLondonUK,King's College LondonChild & Adolescent PsychiatryInstitute of Psychiatry, Psychology & NeuroscienceLondonUK
| | - Katherine A. Johnson
- Melbourne School of Psychological SciencesUniversity of MelbourneMelbourneVic.Australia
| | - Simon P. Kelly
- School of Electrical and Electronic EngineeringUniversity College DublinDublinIreland
| | - Philip Asherson
- King's College LondonMRC Social Genetic and Developmental Psychiatry CentreInstitute of Psychiatry, Psychology & NeuroscienceLondonUK
| | - Jonna Kuntsi
- King's College LondonMRC Social Genetic and Developmental Psychiatry CentreInstitute of Psychiatry, Psychology & NeuroscienceLondonUK
| | - Karen L. Ashwood
- King's College LondonChild & Adolescent PsychiatryInstitute of Psychiatry, Psychology & NeuroscienceLondonUK
| | - Bahare Azadi
- King's College LondonChild & Adolescent PsychiatryInstitute of Psychiatry, Psychology & NeuroscienceLondonUK
| | - Patrick Bolton
- King's College LondonMRC Social Genetic and Developmental Psychiatry CentreInstitute of Psychiatry, Psychology & NeuroscienceLondonUK,King's College LondonChild & Adolescent PsychiatryInstitute of Psychiatry, Psychology & NeuroscienceLondonUK
| | - Gráinne McLoughlin
- King's College LondonMRC Social Genetic and Developmental Psychiatry CentreInstitute of Psychiatry, Psychology & NeuroscienceLondonUK
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Pinto R, Asherson P, Ilott N, Cheung CHM, Kuntsi J. Testing for the mediating role of endophenotypes using molecular genetic data in a twin study of ADHD traits. Am J Med Genet B Neuropsychiatr Genet 2016; 171:982-92. [PMID: 27230021 PMCID: PMC5031223 DOI: 10.1002/ajmg.b.32463] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Accepted: 05/12/2016] [Indexed: 11/11/2022]
Abstract
Family and twin studies have identified endophenotypes that capture familial and genetic risk in attention-deficit/hyperactivity disorder (ADHD), but it remains unclear if they lie on the causal pathway. Here, we illustrate a stepwise approach to identifying intermediate phenotypes. First, we use previous quantitative genetic findings to delineate the expected pattern of genetically correlated phenotypes. Second, we identify overlapping genetic associations with ADHD-related quantitative traits. Finally, we test for the mediating role of associated endophenotypes. We applied this approach to a sample of 1,312 twins aged 7-10. Based on previous twin model-fitting analyses, we selected hyperactivity-impulsivity, inattention, reading difficulties (RD), reaction time variability (RTV) and commission errors (CE), and tested for association with selected ADHD risk alleles. For nominally significant associations with both a symptom and a cognitive variable, matching the expected pattern based on previous genetic correlations, we performed mediation analysis to distinguish pleiotropic from mediating effects. The strongest association was observed for the rs7984966 SNP in the serotonin receptor gene (HTR2A), and RTV (P = 0.007; unadjusted for multiple testing). Mediation analysis suggested that CE (38%) and RTV (44%) substantially mediated the association between inattention and the T-allele of SNP rs3785157 in the norepinephrine transporter gene (SLC6A2) and the T-allele of SNP rs7984966 in HTR2A, respectively. The SNPs tag risk-haplotypes but are not thought to be functionally significant. While these exploratory findings are preliminary, requiring replication, this study demonstrates the value of this approach that can be adapted to the investigation of multiple genetic markers and polygenic risk scores. © 2016 The Authors. American Journal of Medical Genetics Part B: Neuropsychiatric Genetics Published by Wiley Periodicals, Inc.
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Affiliation(s)
- Rebecca Pinto
- MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology and Neuroscience; King's College London; London UK
| | - Philip Asherson
- MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology and Neuroscience; King's College London; London UK
| | - Nicholas Ilott
- The Kennedy Institute of Rheumatology; University of Oxford; Oxford UK
| | - Celeste H. M. Cheung
- MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology and Neuroscience; King's College London; London UK
- Department of Psychology, Institute of Psychiatry, Psychology and Neuroscience; King's College London; London UK
| | - Jonna Kuntsi
- MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology and Neuroscience; King's College London; London UK
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Gonen-Yaacovi G, Arazi A, Shahar N, Karmon A, Haar S, Meiran N, Dinstein I. Increased ongoing neural variability in ADHD. Cortex 2016; 81:50-63. [PMID: 27179150 DOI: 10.1016/j.cortex.2016.04.010] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Revised: 12/31/2015] [Accepted: 04/07/2016] [Indexed: 11/30/2022]
Abstract
Attention Deficit Hyperactivity Disorder (ADHD) has been described as a disorder where frequent lapses of attention impair the ability of an individual to focus/attend in a sustained manner, thereby generating abnormally large intra-individual behavioral variability across trials. Indeed, increased reaction time (RT) variability is a fundamental behavioral characteristic of individuals with ADHD found across a large number of cognitive tasks. But what is the underlying neurophysiology that might generate such behavioral instability? Here, we examined trial-by-trial EEG response variability to visual and auditory stimuli while subjects' attention was diverted to an unrelated task at the fixation cross. Comparisons between adult ADHD and control participants revealed that neural response variability was significantly larger in the ADHD group as compared with the control group in both sensory modalities. Importantly, larger trial-by-trial variability in ADHD was apparent before and after stimulus presentation as well as in trials where the stimulus was omitted, suggesting that ongoing (rather than stimulus-evoked) neural activity is continuously more variable (noisier) in ADHD. While the patho-physiological mechanisms causing this increased neural variability remain unknown, they appear to act continuously rather than being tied to a specific sensory or cognitive process.
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Affiliation(s)
- Gil Gonen-Yaacovi
- Department of Psychology, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Ayelet Arazi
- Department of Psychology, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Nitzan Shahar
- Department of Psychology, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Anat Karmon
- Department of Psychology, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Shlomi Haar
- Department of Cognitive and Brain Science, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Nachshon Meiran
- Department of Psychology, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Ilan Dinstein
- Department of Psychology, Ben-Gurion University of the Negev, Beer-Sheva, Israel; Department of Cognitive and Brain Science, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
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Piper B, Mueller ST, Talebzadeh S, Ki MJ. Evaluation of the validity of the Psychology Experiment Building Language tests of vigilance, auditory memory, and decision making. PeerJ 2016; 4:e1772. [PMID: 27014512 PMCID: PMC4806597 DOI: 10.7717/peerj.1772] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Accepted: 02/16/2016] [Indexed: 11/20/2022] Open
Abstract
Background. The Psychology Experimental Building Language (PEBL) test battery (http://pebl.sourceforge.net/) is a popular application for neurobehavioral investigations. This study evaluated the correspondence between the PEBL and the non-PEBL versions of four executive function tests. Methods. In one cohort, young-adults (N = 44) completed both the Conner’s Continuous Performance Test (CCPT) and the PEBL CPT (PCPT) with the order counter-balanced. In a second cohort, participants (N = 47) completed a non-computerized (Wechsler) and a computerized (PEBL) Digit Span (WDS or PDS) both Forward and Backward. Participants also completed the Psychological Assessment Resources or the PEBL versions of the Iowa Gambling Task (PARIGT or PEBLIGT). Results. The between-test correlations were moderately high (reaction time r = 0.78, omission errors r = 0.65, commission errors r = 0.66) on the CPT. DS Forward was significantly greater than DS Backward on the WDS (p < .0005) and the PDS (p < .0005). The total WDS score was moderately correlated with the PDS (r = 0.56). The PARIGT and the PEBLIGTs showed a very similar pattern for response times across blocks, development of preference for Advantageous over Disadvantageous Decks, and Deck selections. However, the amount of money earned (score–loan) was significantly higher in the PEBLIGT during the last Block. Conclusions. These findings are broadly supportive of the criterion validity of the PEBL measures of sustained attention, short-term memory, and decision making. Select differences between workalike versions of the same test highlight how detailed aspects of implementation may have more important consequences for computerized testing than has been previously acknowledged.
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Affiliation(s)
- Brian Piper
- Neuroscience Program, Bowdoin College, Brunswick, ME, United States; Department of Psychology, Willamette University, Salem, OR, United States; School of Pharmacy, Husson University, Bangor, ME, United States
| | - Shane T Mueller
- Cognitive and Learning Sciences, Michigan Technological University , Houghton, MI , United States
| | - Sara Talebzadeh
- Department of Biology, Husson University , Bangor, ME , United States
| | - Min Jung Ki
- School of Pharmacy, Husson University , Bangor, ME , United States
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Henríquez-Henríquez M, Solari S, Várgas G, Vásquez L, Allende F, Castañón S C, Tenorio M, Quiroga Gutiérrez T. ω-3 Long-Chain Polyunsaturated Fatty Acids and Fatty Acid Desaturase Activity Ratios as Eventual Endophenotypes for ADHD. J Atten Disord 2015; 19:977-86. [PMID: 23100268 DOI: 10.1177/1087054712461175] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
OBJECTIVE Epidemiological studies suggest that long-chain polyunsaturated fatty acids (LC-PUFAs) may be suitable as endophenotypes for ADHD. To be appropriated vulnerability traits, endophenotypes should be altered in unaffected relatives of index cases. Serum profiles of LC-PUFAs in unaffected relatives of ADHD patients remain understudied. The main objective of this study was to compare serum LC-PUFAs in ADHD patients, unaffected relatives of index cases, and general-population unaffected participants. METHOD LC-PUFA profiles of 72 participants (27 ADHD patients, 27 unaffected relatives, and 18 general-population participants) were obtained by gas chromatography-mass spectrometry (GC-MS). Groups were compared by parametrical statistics. RESULTS Unaffected females from the general population presented lower Docosapentaenoic acid (DPA; p = .0012) and a-linolenic acid (ALA; p = .0091) levels compared with ADHD females and unaffected relatives. In addition, docosahexaenoic acid (DHA)/ALA and DHA/DPA ratios, addressing desaturase activity, were significantly lower in ADHD patients and unaffected relatives of ADHD patients in the female-subgroup (p = .022 and .04, respectively). CONCLUSION DHA/ALA, DHA/DPA, serum DPA, and serum ALA may be suitable as endophenotypes for ADHD women.
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Affiliation(s)
| | - Sandra Solari
- Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Gisela Várgas
- Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Luis Vásquez
- Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Fidel Allende
- Pontificia Universidad Católica de Chile, Santiago, Chile
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Moderators of neuropsychological mechanism in attention-deficit hyperactivity disorder. JOURNAL OF ABNORMAL CHILD PSYCHOLOGY 2015; 43:271-81. [PMID: 25037459 DOI: 10.1007/s10802-014-9904-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Neuropsychological measures have been proposed as both a way to tap mechanisms and as endophenotypes for child ADHD. However, substantial evidence supporting heterogeneity in neuropsychological performance among youth with ADHD as well as apparent effect differences by sex, age, and comorbidity have slowed progress. To address this, it is important to understand sibling effects in relation to these moderators. 461 youth ages 6-17 years (54.8 % male, including 251 youth with ADHD, 107 of their unaffected biological siblings, and 103 non-ADHD controls) completed diagnostic interviews and a theoretically informed battery of neuropsychological functioning. A structural equation model was used to consolidate neuropsychological domains. Group differences between unaffected siblings of youth with ADHD and controls across each domain were first examined as the primary endophenotype test for ADHD. Moderation of these effects was evaluated via investigation of interactions between diagnostic group and both proband and individual level characteristics, including sex, age, and comorbidity status. Unaffected siblings performed worse than control youth in the domains of inhibition, response time variability, and temporal information processing. Individual age moderated these effects, such that differences between controls and unaffected siblings were pronounced among younger children (ages 6-10 years) but absent among older youth (ages 11-17 years). Evidence for moderation of effects by proband sex and comorbidity status produced more variable and smaller effects. Results support the utility of inhibition, response time variability, and temporal processing as useful endophenotypes for ADHD in future genetic associations studies of the disorder, but suggest this value will vary by age among unaffected family members.
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Cheung CHM, Rijdijk F, McLoughlin G, Faraone SV, Asherson P, Kuntsi J. Childhood predictors of adolescent and young adult outcome in ADHD. J Psychiatr Res 2015; 62:92-100. [PMID: 25680235 PMCID: PMC4480336 DOI: 10.1016/j.jpsychires.2015.01.011] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Revised: 01/14/2015] [Accepted: 01/19/2015] [Indexed: 11/18/2022]
Abstract
BACKGROUND Attention-deficit/hyperactivity disorder (ADHD) often persists into adulthood, but it remains unclear which childhood factors predict future outcome. AIM To identify childhood predictors of ADHD outcome using both dimensional and categorical approaches. METHODS 116 adolescents and young adults with childhood ADHD were followed up on average 6.6 years later. ADHD outcome variables were interview-based parent-reported ADHD symptoms and impairment. Childhood predictors included parent- and teacher-rated ADHD symptoms and co-occurring behaviours; actigraph measures of activity level; socio-economic status (SES); and cognitive measures previously associated with ADHD. RESULTS Of the sample, 79% continued to meet clinical criteria of ADHD in adolescence and young adulthood. Higher parent-rated ADHD symptoms and movement intensity in childhood, but not teacher-rated symptoms, predicted ADHD symptoms at follow up. Co-occurring symptoms of oppositional behaviours, anxiety, social and emotional problems were also significant predictors, but these effects disappeared after controlling for ADHD symptoms. IQ and SES were significant predictors of both ADHD symptoms and impairment at follow up, but no other cognitive measures significantly predicted outcome. CONCLUSIONS SES and IQ emerge as potential moderators for the prognosis of ADHD. Childhood severity of ADHD symptoms, as measured by parent ratings and actigraph movement intensity, also predicts later ADHD outcome. These factors should be considered when identifying ADHD children at most risk of poor long-term outcomes and for the development of interventions to improve prognosis.
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Affiliation(s)
- Celeste H M Cheung
- MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK; Department of Psychology, Institute of Psychiatry, Psychology & Neuroscience, King's College London, UK
| | - Fruhling Rijdijk
- MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Gráinne McLoughlin
- MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Stephen V Faraone
- Departments of Psychiatry and of Neuroscience and Physiology, SUNY Upstate Medical University, Syracuse, USA
| | - Philip Asherson
- MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Jonna Kuntsi
- MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK.
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Abstract
In addition to the symptoms singled out by the diagnostic criteria for Attention-Deficit Hyperactivity Disorder (ADHD), a comprehensive definition should inform us of the events that trigger ADHD in both its acute and chronic manifestations; the neurobiology that underlies it; and the evolutionary forces that have kept it in the germ line of our species. These factors are organized in terms of Aristotle's four kinds of "causes," or explanations: formal, efficient, material, and final. This framework systematizes the nosology, biology, psychology, and evolutionary pressures that cause ADHD.
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Frazier-Wood AC, Carnell S, Pena O, Hughes SO, O’Connor TM, Asherson P, Kuntsi J. Cognitive performance and BMI in childhood: Shared genetic influences between reaction time but not response inhibition. Obesity (Silver Spring) 2014; 22:2312-8. [PMID: 25376398 PMCID: PMC4313367 DOI: 10.1002/oby.20862] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Accepted: 07/23/2014] [Indexed: 11/10/2022]
Abstract
OBJECTIVE The aim of this work is to understand whether shared genetic influences can explain the association between obesity and cognitive performance, including slower and more variable reaction times (RTs) and worse response inhibition. METHODS RT on a four-choice RT task and the go/no-go task, and commission errors on the go/no-go task for 1,312 twins ages 7-10 years were measured. BMI was measured at 9-12 years. Biometric twin models were run to give an estimate of the genetic correlation (rG ) between body mass index (BMI) and three cognitive measures: mean RT (MRT), RT variability (RTV; the standard deviation of RTs), and commission errors (a measure of response inhibition). RESULTS Genetic correlations indicated that 20%-30% of the genes underlying BMI were shared with both RT measures. However, only small phenotypic correlations between MRT and RTV with later BMI (rPh = ∼0.1) were observed. Commission errors were unassociated with later BMI (rPh = -0.03, ns). CONCLUSIONS Our results are the first to demonstrate significant shared genetic effects between RT performance and BMI. Our findings add biological support to the notion that obesity is associated with slower and more variable RTs. However, our results also emphasize the small nature of the association, which may explain previous negative findings.
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Affiliation(s)
- Alexis C. Frazier-Wood
- USDA/ARS Children’s Nutrition Research Center, Baylor College of Medicine, Houston, Texas, USA
| | - Susan Carnell
- Division of Child and Adolescent Psychiatry, Department of Psychiatry and Behavioral Sciences, Johns Hopkins University, Baltimore, Maryland, USA
| | - Oscar Pena
- Division of Epidemiology, Human Genetics and Environmental Sciences, The University of Texas Health Sciences Center, Houston, Texas, USA
| | - Sheryl O. Hughes
- USDA/ARS Children’s Nutrition Research Center, Baylor College of Medicine, Houston, Texas, USA
| | - Teresia M. O’Connor
- USDA/ARS Children’s Nutrition Research Center, Baylor College of Medicine, Houston, Texas, USA
| | - Philip Asherson
- King’s College London, MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, De Crespigny Park, London, UK
| | - Jonna Kuntsi
- King’s College London, MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, De Crespigny Park, London, UK
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Heym N, Kantini E, Checkley HLR, Cassaday HJ. Tourette-like behaviors in the normal population are associated with hyperactive/impulsive ADHD-like behaviors but do not relate to deficits in conditioned inhibition or response inhibition. Front Psychol 2014; 5:946. [PMID: 25228890 PMCID: PMC4151087 DOI: 10.3389/fpsyg.2014.00946] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2014] [Accepted: 08/07/2014] [Indexed: 11/21/2022] Open
Abstract
Attention-Deficit Hyperactivity Disorder (ADHD) and Tourette Syndrome (TS) present as distinct conditions clinically; however, comorbidity and inhibitory control deficits have been proposed for both. Whilst such deficits have been studied widely within clinical populations, findings are mixed—partly due to comorbidity and/or medication effects—and studies have rarely distinguished between subtypes of the disorders. Studies in the general population are sparse. Using a continuity approach, the present study examined (i) the relationships between inattentive and hyperactive/impulsive aspects of ADHD and TS-like behaviors in the general population, and (ii) their unique associations with automatic and executive inhibitory control, as well as (iii) yawning (a proposed behavioral model of TS). One hundred and thirty-eight participants completed self-report measures for ADHD and TS-like behaviors as well as yawning, and a conditioned inhibition task to assess automatic inhibition. A sub-sample of fifty-four participants completed three executive inhibition tasks. An exploratory factor analysis of the TS behavior checklist supported a distinction between phonic and motor like pure TS behaviors. Whilst hyperactive/impulsive aspects of ADHD were associated with increased pure and compulsive TS-like behaviors, inattention in isolation was related to reduced obsessive-compulsive TS-like behaviors. TS-like behaviors were associated with yawning during situations of inactivity, and specifically motor TS was related to yawning during stress. Phonic TS and inattention aspects of ADHD were associated with yawning during concentration/activity. Whilst executive interference control deficits were linked to hyperactive/impulsive ADHD-like behaviors, this was not the case for inattentive ADHD or TS-like behaviors, which instead related to increased performance on some measures. No associations were observed for automatic conditioned inhibition.
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Affiliation(s)
- Nadja Heym
- School of Psychology, University of Nottingham Nottingham, UK ; Division of Psychology, School of Social Science, Nottingham Trent University Nottingham, UK
| | - Ebrahim Kantini
- School of Psychology, University of Nottingham Nottingham, UK
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Cheung CHM, Fazier-Wood AC, Asherson P, Rijsdijk F, Kuntsi J. Shared cognitive impairments and aetiology in ADHD symptoms and reading difficulties. PLoS One 2014; 9:e98590. [PMID: 24886915 PMCID: PMC4041781 DOI: 10.1371/journal.pone.0098590] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Accepted: 05/05/2014] [Indexed: 12/31/2022] Open
Abstract
Background Twin studies indicate that the frequent co-occurrence of attention deficit hyperactivity disorder (ADHD) symptoms and reading difficulties (RD) is largely due to shared genetic influences. Both disorders are associated with multiple cognitive impairments, but it remains unclear which cognitive impairments share the aetiological pathway, underlying the co-occurrence of the symptoms. We address this question using a sample of twins aged 7–10 and a range of cognitive measures previously associated with ADHD symptoms or RD. Methods We performed multivariate structural equation modelling analyses on parent and teacher ratings on the ADHD symptom domains of inattention and hyperactivity, parent ratings on RD, and cognitive data on response inhibition (commission errors, CE), reaction time variability (RTV), verbal short-term memory (STM), working memory (WM) and choice impulsivity, from a population sample of 1312 twins aged 7–10 years. Results Three cognitive processes showed significant phenotypic and genetic associations with both inattention symptoms and RD: RTV, verbal WM and STM. While STM captured only 11% of the shared genetic risk between inattention and RD, the estimates increased somewhat for WM (21%) and RTV (28%); yet most of the genetic sharing between inattention and RD remained unaccounted for in each case. Conclusion While response inhibition and choice impulsivity did not emerge as important cognitive processes underlying the co-occurrence between ADHD symptoms and RD, RTV and verbal memory processes separately showed significant phenotypic and genetic associations with both inattention symptoms and RD. Future studies employing longitudinal designs will be required to investigate the developmental pathways and direction of causality further.
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Affiliation(s)
- Celeste H. M. Cheung
- MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, King's College London, London, United Kingdom
| | - Alexis C. Fazier-Wood
- Human Genetics Center, Division of Epidemiology, Human Genetics and Environmental Science, School of Public Health, University of Texas Health Sciences Center at Houston, Houston, Texas, United States of America
| | - Philip Asherson
- MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, King's College London, London, United Kingdom
| | - Fruhling Rijsdijk
- MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, King's College London, London, United Kingdom
| | - Jonna Kuntsi
- MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, King's College London, London, United Kingdom
- * E-mail:
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Lowe CJ, Hall PA, Vincent CM, Luu K. The effects of acute aerobic activity on cognition and cross-domain transfer to eating behavior. Front Hum Neurosci 2014; 8:267. [PMID: 24808850 PMCID: PMC4011066 DOI: 10.3389/fnhum.2014.00267] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Accepted: 04/10/2014] [Indexed: 02/05/2023] Open
Abstract
Prior studies have demonstrated that a single session of aerobic exercise can enhance cognitive functioning; specifically, the inhibition facet of executive function (EF). Additionally, previous research has demonstrated that inhibitory abilities are essential for effective dietary self-control. However, it is currently unknown whether exercise induced enhancements in EF also facilitate self-control in the dietary domain. The present study sought to determine whether a single session of aerobic exercise enhances EF, and whether there is a transfer effect to dietary self-control. Thirty four undergraduate students were randomly assigned to one of three exercise conditions: (1) minimal exercise; (2) moderate intensity exercise (30% heart rate reserve); (3) vigorous intensity exercise (50% heart rate reserve). After the exercise bout, participants completed three standardized EF tasks followed by a bogus taste test for three appetitive snack foods (milk chocolate and potato chips) and two control foods (dark chocolate and crackers). The amount of food consumed during the taste test was covertly measured. The results revealed a significant main effect of treatment condition on the Stroop task performance, but not Go-NoGo (GNG) and Stop Signal task performance. Findings with respect to food consumption revealed that EF moderated the treatment effect, such that those with larger exercise effects on Stroop performance in the moderate intensity exercise condition consumed more control foods (but not less appetitive foods). These findings support the contention that a single bout of aerobic exercise enhances EF, and may have transfer effects to the dietary domain, but that such effects may be indirect in nature.
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Affiliation(s)
- Cassandra J Lowe
- School of Public Health and Health Systems, University of Waterloo Waterloo, ON, Canada
| | - Peter A Hall
- School of Public Health and Health Systems, University of Waterloo Waterloo, ON, Canada ; Department of Kinesiology, University of Waterloo Waterloo, ON, Canada
| | - Corita M Vincent
- School of Public Health and Health Systems, University of Waterloo Waterloo, ON, Canada
| | - Kimberley Luu
- School of Public Health and Health Systems, University of Waterloo Waterloo, ON, Canada
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Genetic overlap between ADHD symptoms and EEG theta power. Brain Cogn 2014; 87:168-72. [PMID: 24752036 DOI: 10.1016/j.bandc.2014.03.010] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2013] [Revised: 02/20/2014] [Accepted: 03/17/2014] [Indexed: 01/30/2023]
Abstract
Biological markers that are grounded in neuroscience may facilitate understanding of the pathophysiology of complex psychiatric disorders. One of the most consistent and robust neural abnormalities in attention deficit hyperactivity disorder (ADHD) is increased EEG power in the theta band at rest (4-8Hz). The present study used a twin design to estimate the extent of genetic overlap between increased theta power and risk for ADHD in order to validate theta power as a marker of genetic risk for ADHD. At rest, EEG was measured in 30 monozygotic and dizygotic adolescent twin pairs concordant or discordant for high ADHD symptom scores and 37 monozygotic and dizygotic control twin pairs with low ADHD symptom scores. Structural equation modelling was used to estimate the heritability of theta power and partition the genetic and environmental contributions to the overlap between ADHD and theta power. A significant phenotypic correlation between ADHD symptoms and elevated theta power was found. Theta power demonstrated moderate to high heritability estimates (0.77) and moderate genetic correlations with ADHD (0.35) suggesting shared genetic influences. Increased theta power is a candidate biological marker of genetic risk for ADHD, which warrants further investigation of the neurobiological mechanisms that underlie the genetic relationship.
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Reh V, Schmidt M, Rief W, Christiansen H. Preliminary evidence for altered motion tracking-based hyperactivity in ADHD siblings. Behav Brain Funct 2014; 10:7. [PMID: 24624931 PMCID: PMC3995616 DOI: 10.1186/1744-9081-10-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Accepted: 02/18/2014] [Indexed: 12/02/2022] Open
Abstract
Background It is well-established that ADHD children have deficits in executive functions such as performance variability and sustained attention. It has been suggested that these deficits are intermediate phenotypes. Hyperactivity, a core symptom of ADHD, has not yet been explored as a potential intermediate phenotype in ADHD. The computerized Quantified behavior Test (QbTest) is a combined continuous performance and activity test that assesses hyperactivity, inattention, and impulsivity separately. The aim of the present study was to (1) investigate the utility of objectively measured motor activity as a potential intermediate phenotype in ADHD, and (2) explore intermediate phenotypes for ADHD at the factor instead of single variable level. Method Forty-five ADHD children, 22 non-affected siblings, and 45 unrelated controls with no family history of ADHD performed the QbTest. Effects of familiality as well as influences of age and gender on QbTest symptom dimensions were tested. Results ADHD children showed the greatest impairments on all three QbTest factors, followed by their non-affected siblings, with control children showing the lowest scores. Group differences between the non-affected siblings and controls were only significant for the motion tracking-based Hyperactivity factor. Results were independent of age and gender. Conclusion Hyperactivity assessed by a motion tracking system may be a useful intermediate phenotype in ADHD. Prospective research should use larger samples to further examine the QbTest factors, especially the motion tracking-based Hyperactivity factor which may be a candidate for an intermediate phenotype in ADHD.
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Affiliation(s)
- Verena Reh
- Department of Clinical Psychology, University of Marburg, Marburg, Germany.
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Weir RK, Dudley JA, Yan TC, Grabowska EM, Peña-Oliver Y, Ripley TL, Stephens DN, Stanford SC, Hunt SP. The influence of test experience and NK1 receptor antagonists on the performance of NK1R-/- and wild type mice in the 5-Choice Serial Reaction-Time Task. J Psychopharmacol 2014; 28:270-81. [PMID: 23845920 DOI: 10.1177/0269881113495722] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Genetically-altered mice, lacking functional NK1 receptors (NK1R-/-), express abnormal behaviours that are prominent in Attention Deficit Hyperactivity Disorder: namely, inattentiveness and impulsivity (indicated by their greater % omissions and premature responses in the 5-Choice Serial Reaction-Time Task (5-CSRTT) and locomotor hyperactivity. We investigated how behaviour in the 5-CSRTT is affected by repeated testing and whether the abnormalities expressed by NK1R-/- mice are mimicked by treating wild type mice with a NK1R antagonist (L 733060 or RP 67580; 5 or 10 mg/kg). Repeated testing with a variable (VITI) or fixed, prolonged (LITI) intertrial interval reduced % omissions. Premature responses also declined, but only in NK1R-/- mice, in the VITI test. By contrast, perseveration increased in both genotypes. RP 67580 (10 mg/kg) increased the % omissions in both genotypes in the VITI, an action which cannot be attributed to NK1R antagonism. Neither drug affected perseveration. However, for premature responses, the response profile suggested that the low and high doses of RP 67580 (VITI) and L 733060 (LITI) had opposing effects on this behaviour. We infer that the effect of NK1R antagonists in the 5-CSRTT is confounded by animals' test experience and non-specific drug effects at sites other than NK1R, possibly L-type Ca²⁺(v) channels.
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Affiliation(s)
- R K Weir
- 1University College London, London, UK
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Kuntsi J, Pinto R, Price TS, van der Meere JJ, Frazier-Wood AC, Asherson P. The separation of ADHD inattention and hyperactivity-impulsivity symptoms: pathways from genetic effects to cognitive impairments and symptoms. JOURNAL OF ABNORMAL CHILD PSYCHOLOGY 2014; 42:127-36. [PMID: 23839718 PMCID: PMC4520068 DOI: 10.1007/s10802-013-9771-7] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Both shared and unique genetic risk factors underlie the two symptom domains of attention deficit hyperactivity disorder (ADHD): inattention and hyperactivity-impulsivity. The developmental course and relationship to co-occurring disorders differs across the two symptom domains, highlighting the importance of their partially distinct etiologies. Familial cognitive impairment factors have been identified in ADHD, but whether they show specificity in relation to the two ADHD symptom domains remains poorly understood. We aimed to investigate whether different cognitive impairments are genetically linked to the ADHD symptom domains of inattention versus hyperactivity-impulsivity. We conducted multivariate genetic model fitting analyses on ADHD symptom scores and cognitive data, from go/no-go and fast tasks, collected on a population twin sample of 1,312 children aged 7-10. Reaction time variability (RTV) showed substantial genetic overlap with inattention, as observed in an additive genetic correlation of 0.64, compared to an additive genetic correlation of 0.31 with hyperactivity-impulsivity. Commission errors (CE) showed low additive genetic correlations with both hyperactivity-impulsivity and inattention (genetic correlations of 0.17 and 0.11, respectively). The additive genetic correlation between RTV and CE was also low and non-significant at -0.10, consistent with the etiological separation between the two indices of cognitive impairments. Overall, two key cognitive impairments phenotypically associated with ADHD symptoms, captured by RTV and CE, showed different genetic relationships to the two ADHD symptom domains. The findings extend a previous model of two familial cognitive impairment factors in combined subtype ADHD by separating pathways underlying inattention and hyperactivity-impulsivity symptoms.
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Affiliation(s)
- Jonna Kuntsi
- MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, King's College London, De Crespigny Park, London, SE5 8AF, UK,
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Macdonald JA, Beauchamp MH, Crigan JA, Anderson PJ. Age-related differences in inhibitory control in the early school years. Child Neuropsychol 2013; 20:509-26. [PMID: 23909718 DOI: 10.1080/09297049.2013.822060] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
The transition to school is associated with a greater requirement to inhibit irrelevant or inappropriate thought and behavior in order to concentrate on effective learning and to interact successfully with peers. Current knowledge of inhibitory control development in the early school years is limited due to a lack of normative data from age-appropriate, sensitive measures. In this study, three pictorial versions of the Stroop task were administered to investigate inhibitory control development in early school-aged children. Age-related trajectories of inhibition and effects of gender were examined in 80 children (42 boys) aged 5 to 8 years. All children were assessed with the Cognitive Assessment System Expressive Attention subtest (Big-Small Stroop), Fruit Stroop, and Boy-Girl Stroop. The Big-Small Stroop revealed substantial age-related improvement in inhibition from 5 to 7 years with a levelling of performance at 8 years of age, while the Fruit Stroop and Boy-Girl Stroop demonstrated clear but nonsignificant age trends. In particular, older children committed fewer errors and corrected their errors more frequently than younger children. Performance on all Stroop tasks correlated significantly, providing evidence that they tap similar cognitive abilities. Some gender differences were found. This study indicates that inhibitory skills develop rapidly in the early school years and suggests that error awareness may be a useful indicator of the development of cognitive inhibition for this age group.
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Affiliation(s)
- Jacqui A Macdonald
- a Melbourne School of Psychological Sciences , University of Melbourne , Melbourne , Australia
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42
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Kuntsi J, Frazier-Wood AC, Banaschewski T, Gill M, Miranda A, Oades RD, Roeyers H, Rothenberger A, Steinhausen HC, van der Meere JJ, Faraone SV, Asherson P, Rijsdijk F. Genetic analysis of reaction time variability: room for improvement? Psychol Med 2013; 43:1323-1333. [PMID: 22975296 PMCID: PMC3801159 DOI: 10.1017/s0033291712002061] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2012] [Revised: 07/26/2012] [Accepted: 07/27/2012] [Indexed: 11/18/2022]
Abstract
BACKGROUND Increased reaction time variability (RTV) on cognitive tasks requiring a speeded response is characteristic of several psychiatric disorders. In attention deficit hyperactivity disorder (ADHD), the association with RTV is strong phenotypically and genetically, yet high RTV is not a stable impairment but shows ADHD-sensitive improvement under certain conditions, such as those with rewards. The state regulation theory proposed that the RTV difference score, which captures change from baseline to a rewarded or fast condition, specifically measures 'state regulation'. By contrast, the interpretation of RTV baseline (slow, unrewarded) scores is debated. We aimed to investigate directly the degree of phenotypic and etiological overlap between RTV baseline and RTV difference scores. Method We conducted genetic model fitting analyses on go/no-go and fast task RTV data, across task conditions manipulating rewards and event rate, from a population-based twin sample (n=1314) and an ADHD and control sibling-pair sample (n=1265). RESULTS Phenotypic and genetic/familial correlations were consistently high (0.72-0.98) between RTV baseline and difference scores, across tasks, manipulations and samples. By contrast, correlations were low between RTV in the manipulated condition and difference scores. A comparison across two different go/no-go task RTV difference scores (slow-fast/slow-incentive) showed high phenotypic and genetic/familial overlap (r = 0.75-0.83). CONCLUSIONS Our finding that RTV difference scores measure largely the same etiological process as RTV under baseline condition supports theories emphasizing the malleability of the observed high RTV. Given the statistical shortcomings of difference scores, we recommend the use of RTV baseline scores for most analyses, including genetic analyses.
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Affiliation(s)
- J Kuntsi
- King's College London, MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, UK.
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Wöstmann NM, Aichert DS, Costa A, Rubia K, Möller HJ, Ettinger U. Reliability and plasticity of response inhibition and interference control. Brain Cogn 2013; 81:82-94. [DOI: 10.1016/j.bandc.2012.09.010] [Citation(s) in RCA: 139] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2011] [Revised: 08/27/2012] [Accepted: 09/20/2012] [Indexed: 11/15/2022]
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Dudley JA, Weir RK, Yan TC, Grabowska EM, Grimmé AJ, Amini S, Stephens DN, Hunt SP, Stanford SC. Antagonism of L-type Ca(v) channels with nifedipine differentially affects performance of wildtype and NK1R-/- mice in the 5-Choice Serial Reaction-Time Task. Neuropharmacology 2012; 64:329-36. [PMID: 22884624 DOI: 10.1016/j.neuropharm.2012.06.056] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2012] [Revised: 06/23/2012] [Accepted: 06/26/2012] [Indexed: 12/11/2022]
Abstract
Mice with functional ablation of the substance P-preferring receptor gene ('Nk1r' in mice ('NK1R-/-'), 'TACR1' in humans) display deficits in cognitive performance that resemble those seen in patients with Attention Deficit Hyperactivity Disorder (ADHD): namely, inattentiveness, impulsivity and perseveration. A recent report suggested that the L-type Ca(v) channel blocker, nifedipine, can ameliorate behavioral abnormalities of this type in humans. In light of evidence that NK1R antagonists modulate the opening of these L-type channels, we investigated whether nifedipine modifies %premature responses (impulsivity), perseveration or %omissions (inattentiveness) in the 5-Choice Serial Reaction-Time Task (5-CSRTT) and whether the response differs in NK1R-/- and wildtype mice. %Premature responses and perseveration were reduced in both genotypes, although wildtype mice were more sensitive to the effects of nifedipine than NK1R-/- mice. By contrast, nifedipine greatly increased %omissions but, again, was more potent in wildtypes. %Accuracy and locomotor activity were unaffected in either genotype. We infer that behavior of mice in the 5-CSRTT depends on the regulation of striato-cortical networks by L-type Ca(v) channels and NK1R. We further suggest that disruption of NK1R signaling in patients with ADHD, especially those with polymorphisms of the TACR1 gene, could lead to compensatory changes in the activity of L-type channels that underlie or exacerbate their problems. This article is part of a Special Issue entitled 'Cognitive Enhancers'.
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Affiliation(s)
- Julia A Dudley
- Department of Cell and Developmental Biology, University College London (UCL), Gower Street, London WC1E 6BT, UK
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45
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Müller U, Kerns KA, Konkin K. Test–Retest Reliability and Practice Effects of Executive Function Tasks in Preschool Children. Clin Neuropsychol 2012; 26:271-87. [DOI: 10.1080/13854046.2011.645558] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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46
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Hunsaker MR. Comprehensive neurocognitive endophenotyping strategies for mouse models of genetic disorders. Prog Neurobiol 2012; 96:220-41. [PMID: 22266125 PMCID: PMC3289520 DOI: 10.1016/j.pneurobio.2011.12.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2011] [Revised: 12/06/2011] [Accepted: 12/20/2011] [Indexed: 01/21/2023]
Abstract
There is a need for refinement of the current behavioral phenotyping methods for mouse models of genetic disorders. The current approach is to perform a behavioral screen using standardized tasks to define a broad phenotype of the model. This phenotype is then compared to what is known concerning the disorder being modeled. The weakness inherent in this approach is twofold: First, the tasks that make up these standard behavioral screens do not model specific behaviors associated with a given genetic mutation but rather phenotypes affected in various genetic disorders; secondly, these behavioral tasks are insufficiently sensitive to identify subtle phenotypes. An alternate phenotyping strategy is to determine the core behavioral phenotypes of the genetic disorder being studied and develop behavioral tasks to evaluate specific hypotheses concerning the behavioral consequences of the genetic mutation. This approach emphasizes direct comparisons between the mouse and human that facilitate the development of neurobehavioral biomarkers or quantitative outcome measures for studies of genetic disorders across species.
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Affiliation(s)
- Michael R Hunsaker
- Department of Neurological Surgery, University of California, Davis, Davis, CA 95616, USA.
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Buzy WM, Medoff DR, Schweitzer JB. Intra-individual variability among children with ADHD on a working memory task: an ex-Gaussian approach. Child Neuropsychol 2012; 15:441-59. [PMID: 19184779 DOI: 10.1080/09297040802646991] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Intra-individual variability on a computer-based working memory task was examined among 25 children/adolescents with ADHD and 24 typically developing peers. Participants completed the Visual Serial Addition Task (VSAT) and reaction time data were fit to an ex-Gaussian distribution. ADHD participants demonstrated significantly more variable performance than controls, and effects of working memory load were observed. Event rate, however, had no influence on group differences in performance. Follow-up correlations revealed associations between VSAT performance and ADHD symptomatology. This study supports intra-individual variability as a hallmark feature of ADHD beyond the domain of response inhibition and reinforces the need to consider variability in ADHD more broadly.
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Affiliation(s)
- Wendy M Buzy
- Division of Child and Adolescent Psychiatry, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, Maryland, USA
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Schweitzer JB, Fassbender C, Lit L, Reeves GM, Powell SPH. Attention-deficit/hyperactivity disorder. HANDBOOK OF CLINICAL NEUROLOGY 2012; 106:391-405. [PMID: 22608633 DOI: 10.1016/b978-0-444-52002-9.00022-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Julie B Schweitzer
- Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Sacramento, CA, USA.
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An exploration of the associations of pregnancy and perinatal features with cytokines and tryptophan/kynurenine metabolism in children with attention-deficit hyperactivity disorder (ADHD). ACTA ACUST UNITED AC 2011; 3:301-18. [PMID: 21785943 DOI: 10.1007/s12402-011-0062-2] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2011] [Accepted: 07/08/2011] [Indexed: 10/18/2022]
Abstract
Intra-individual variability of the characteristics of children with attention-deficit hyperactivity (ADHD) may reflect compromised glial energy supply in the synapse. We reported recently that while serum levels of a glial marker, the cytokine S100B, were not seriously altered, levels of other cytokines and tryptophan metabolites were related to symptoms, attention and variability. Here, we explore with a regression analysis whether levels of these substances were associated with features of the index pregnancy of potential aetiological significance. Serum was taken from 35 children with DSM-IV ADHD (14 on medication) and 21 typically developing controls to measure 8 cytokines (S100B, IL-2, IL-6, IL-10, IL-13, IL-16, TNF-α and IFN-γ) and 5 metabolites (Tryptophan, Kynurenine, Kynurenate [KA], 3-hydroxy-kynurenine [3HK] and 5-hydroxyindole acetic acid [5-HIAA]). The mothers received a 124-item questionnaire on features surrounding the pregnancy. (1) For children with ADHD, a shorter pregnancy and smaller birth weight were associated statistically with increased 3HK and IFN-γ and for obstetric problems with decreased TNF-α levels. (2) Maternal smoking related to decreasing kynurenine and increasing 3HK and S100B levels in ADHD children. Paternal smoking was associated with increased tryptophan in the controls and increased IL-6 levels in ADHD children. (3) The taking of supplements often related to decreasing TNF-α, increasing IL-10 and lower 5-HIAA levels in the ADHD children. Less 5-HIAA but more tryptophan was associated with earlier and later life events, respectively. (4) Increased IL-16 and 5-HIAA levels in the ADHD group related to reports of poorer infant health. Unexpectedly, more child care (seafood and time together) in ADHD than healthy families was implicated by lower tryptophan levels and an altered balance of pro-inflammatory cytokines. Across measures control families generally showed either non-significant associations or the opposite to those of the ADHD group. In ADHD children more than controls, the balance of potentially toxic or protective kynurenine metabolites and of pro- over anti-inflammatory cytokines may reflect the perinatal experience associated with stress, but not with maternal illness.
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Archer T, Oscar-Berman M, Blum K. Epigenetics in Developmental Disorder: ADHD and Endophenotypes. JOURNAL OF GENETIC SYNDROMES & GENE THERAPY 2011; 2:1000104. [PMID: 22224195 PMCID: PMC3250517 DOI: 10.4172/2157-7412.1000104] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Heterogeneity in attention-deficit/hyperactivity disorder (ADHD), with complex interactive operations of genetic and environmental factors, is expressed in a variety of disorder manifestations: severity, co-morbidities of symptoms, and the effects of genes on phenotypes. Neurodevelopmental influences of genomic imprinting have set the stage for the structural-physiological variations that modulate the cognitive, affective, and pathophysiological domains of ADHD. The relative contributions of genetic and environmental factors provide rapidly proliferating insights into the developmental trajectory of the condition, both structurally and functionally. Parent-of-origin effects seem to support the notion that genetic risks for disease process debut often interact with the social environment, i.e., the parental environment in infants and young children. The notion of endophenotypes, markers of an underlying liability to the disorder, may facilitate detection of genetic risks relative to a complex clinical disorder. Simple genetic association has proven insufficient to explain the spectrum of ADHD. At a primary level of analysis, the consideration of epigenetic regulation of brain signalling mechanisms, dopamine, serotonin, and noradrenaline is examined. Neurotrophic factors that participate in the neurogenesis, survival, and functional maintenance of brain systems, are involved in neuroplasticity alterations underlying brain disorders, and are implicated in the genetic predisposition to ADHD, but not obviously, nor in a simple or straightforward fashion. In the context of intervention, genetic linkage studies of ADHD pharmacological intervention have demonstrated that associations have fitted the "drug response phenotype," rather than the disorder diagnosis. Despite conflicting evidence for the existence, or not, of genetic associations between disorder diagnosis and genes regulating the structure and function of neurotransmitters and brain-derived neurotrophic factor (BDNF), associations between symptoms-profiles endophenotypes and single nucleotide polymorphisms appear reassuring.
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Affiliation(s)
- Trevor Archer
- Department of Psychology, University of Gothenburg, Box 500, SE-40530 Gothenburg, Sweden
| | - Marlene Oscar-Berman
- Departments of Psychiatry, Neurology, and Anatomy & Neurobiology, Boston University School of Medicine, and Boston VA Healthcare System, Boston, MA, USA
| | - Kenneth Blum
- Department of Psychiatry, University of Florida College of Medicine, and McKnight Brain Institute, Gainesville, FL, USA
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