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Moradi Siah Afshadi M, Amiri S, Talebi H. Examining the structural equation modeling between intrinsic-motivation, emotion regulation and AHDH: the mediating role of problem-solving, time-management, and behavioral-inhibition. CURRENT PSYCHOLOGY 2023; 43:1-15. [PMID: 36820196 PMCID: PMC9931447 DOI: 10.1007/s12144-023-04289-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/19/2023] [Indexed: 02/17/2023]
Abstract
Although Executive Functions has been considered as the main correlation of ADHD few studies have examined the effect of EFs on ADHD symptoms, in the samples with ADHD. This study aimed to examine the structure of EFs on ADHD students in a hypothesized model. After careful screening of ADHD among 1368 university students (with stratified and multistage cluster sampling), out of them, 211 students with ADHD diagnosis were selected purposefully. They received scales on their emotion regulation, motivation, adult ADHD, deficits in EFs, and diagnostic interview. Emotion regulation and intrinsic motivation were considered as input; behavioral-inhibition, time-management, and problem-solving were the mediators and ADHD subscales were as the output variables. Results showed that the model adequately fit the data. The model fit indices were χ2 = 27.081, df = 1, CFI = 0.99, GFI = 0.97, and PGFI = 0.02. The direct effects of intrinsic-motivation and emotion-regulation on all three mediators and indirect effects of them to ADHD subscales were significant. Based on the results, time-management mediated the relationship between motivation and emotion regulation and ADHD. Among EFs, emotion-regulation and intrinsic-motivation had fundamental influence to other aspects of EFs factors such as behavioral-inhibition, time-management, problem-solving, and attention deficit/hyperactivity disorder.
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Affiliation(s)
- Mahboubeh Moradi Siah Afshadi
- Department of Psychology, Faculty of Education and Psychology, University of Isfahan, Hezar Jarib Street, Azady Square, Isfahan, 8174673441 Iran
| | - Shole Amiri
- Department of Psychology, Faculty of Education and Psychology, University of Isfahan, Hezar Jarib Street, Azady Square, Isfahan, 8174673441 Iran
| | - Hooshang Talebi
- Faculty of Mathematics and Statistics, University of Isfahan, Isfahan, Iran
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Kubrusly RCC, da Rosa Valli T, Ferreira MNMR, de Moura P, Borges-Martins VPP, Martins RS, Ferreira DDP, Sathler MF, de Melo Reis RA, Ferreira GC, Manhães AC, Dos Santos Pereira M. Caffeine Improves GABA Transport in the Striatum of Spontaneously Hypertensive Rats (SHR). Neurotox Res 2021; 39:1946-1958. [PMID: 34637050 DOI: 10.1007/s12640-021-00423-0] [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: 03/09/2021] [Revised: 09/25/2021] [Accepted: 09/27/2021] [Indexed: 11/28/2022]
Abstract
The spontaneously hypertensive rat (SHR) is an excellent animal model that mimics the behavioral and neurochemical phenotype of attention-deficit/hyperactivity disorder (ADHD). Here, we characterized the striatal GABA transport of SHR and investigated whether caffeine, a non-selective antagonist of adenosine receptors, could influence GABAergic circuitry. For this purpose, ex vivo striatal slices of SHR and Wistar (control strain) on the 35th postnatal day were dissected and incubated with [3H]-GABA to quantify the basal levels of uptake and release. SHR exhibited a reduced [3H]-GABA uptake and release, suggesting a defective striatal GABAergic transport system. GAT-1 appears to be the primary transporter for [3H]-GABA uptake in SHR striatum, as GAT-1 selective blocker, NO-711, completely abolished it. We also verified that acute exposure of striatal slices to caffeine improved [3H]-GABA uptake and release in SHR, whereas Wistar rats were not affected. GABA-uptake increase and cAMP accumulation promoted by caffeine was reverted by A1R activation with N6-cyclohexyl adenosine (CHA). As expected, the pharmacological blockade of cAMP-PKA signaling by H-89 also prevented caffeine-mediated [3H]-GABA uptake increment. Interestingly, a single caffeine exposure did not affect GAT-1 or A1R protein density in SHR, which was not different from Wistar protein levels, suggesting that the GAT-1-dependent transport in SHR has a defective functional activity rather than lower protein expression. The current data support that caffeine regulates GAT-1 function and improves striatal GABA transport via A1R-cAMP-PKA signaling, specifically in SHR. These results reinforce that caffeine may have therapeutic use in disorders where the GABA transport system is impaired.
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Affiliation(s)
| | | | | | - Pâmella de Moura
- Laboratório de Neurofarmacologia, Instituto Biomédico, Niterói, RJ, Brazil
| | | | - Robertta Silva Martins
- Laboratório de Neurofarmacologia, Instituto Biomédico, Niterói, RJ, Brazil
- Laboratório de Neurobiologia Celular E Molecular, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal Do Rio de Janeiro, Rio de Janeiro, Brazil
| | | | | | - Ricardo Augusto de Melo Reis
- Laboratório de Neuroquímica, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal Do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Gustavo Costa Ferreira
- Laboratório de Neuroenergética E Erros Inatos Do Metabolismo, Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal Do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Alex Christian Manhães
- Laboratório de Neurofisiologia, Instituto de Biologia, Universidade Do Estado Do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Maurício Dos Santos Pereira
- Laboratório de Neurofarmacologia, Instituto Biomédico, Niterói, RJ, Brazil.
- Laboratório de Neurofisiologia Molecular, Departamento de Biologia Básica E Oral, Faculdade de Odontologia de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil.
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Martella D, Aldunate N, Fuentes LJ, Sánchez-Pérez N. Arousal and Executive Alterations in Attention Deficit Hyperactivity Disorder (ADHD). Front Psychol 2020; 11:1991. [PMID: 32903419 PMCID: PMC7434859 DOI: 10.3389/fpsyg.2020.01991] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Accepted: 07/17/2020] [Indexed: 12/27/2022] Open
Abstract
Attention deficit hyperactivity disorder (ADHD) is the most common neurobehavioral disorder in childhood and can significantly affect a child's personal and social development and academic achievement. Taking into account the model of attentional networks proposed by Posner et al., the aim of the present study was to review the literature regarding two main explicative models of ADHD, i.e., the inhibition model and the cognitive-energetic model, by discussing behavioral and neurological evidence of both models and the limitations of each model. The review highlights evidence that favors the energetic model and points to an unstable arousal as a potential pathogenetic factor in ADHD.
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Affiliation(s)
- Diana Martella
- Facultad de Ciencias Sociales y Humanidades, Instituto de Estudios Sociales y Humanísticos, Universidad Autónoma de Chile, Santiago, Chile
| | - Nerea Aldunate
- Escuela de Psicología, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Luis J. Fuentes
- Departamento de Psicología Básica y Metodología, Facultad de Psicología, Universidad de Murcia, Murcia, Spain
| | - Noelia Sánchez-Pérez
- Departamento de Psicología y Sociología, Facultad de Ciencias Sociales y Humanas, Universidad de Zaragoza, Teruel, Spain
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Sundermann B, Garde S, Dehghan Nayyeri M, Weglage J, Rau J, Pfleiderer B, Feldmann R. Approaching altered inhibitory control in phenylketonuria: A functional MRI study with a Go-NoGo task in young female adults. Eur J Neurosci 2020; 52:3951-3962. [PMID: 32277784 DOI: 10.1111/ejn.14738] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 01/30/2020] [Accepted: 03/31/2020] [Indexed: 11/27/2022]
Abstract
Subtle executive function deficits, particularly regarding inhibitory control, have been reported in patients with phenylketonuria (PKU) despite early dietary treatment. Purpose of this study was to assess whether young female adults with PKU exhibit altered neural activity underlying such deficits, particularly in a fronto-parietal cognitive control network (CCN). Behavioural data and functional magnetic resonance imaging (fMRI) data were acquired during a Go-NoGo task in 16 young adult patients with PKU and 17 control subjects. Hypothesis-driven analyses of behavioural and fMRI data in the CCN were supplemented by exploratory whole brain activation analyses. PKU patients exhibited a trend towards higher errors of commission. Patients exhibited marginally increased activation associated with inhibitory control in only one CCN core region (right middle frontal gyrus, p = .043). Whole brain analyses revealed widespread relatively increased activation in adults with PKU in the main task contrast (NoGo > Go). This increased activation was mainly observed outside the CCN and largely overlapped with the default mode network (DMN). In conclusion, only subtle inhibitory control deficits and associated brain activity differences were observed in young adults with PKU. Thus, this work adds to the notion that this particular population seems to be only slightly affected by such cognitive deficits. While there were also only minimal increases when compared to healthy subjects in brain activity in a cognitive control network, we observed more widespread activation increases outside this network. These results support the assumption of DMN dysfunction in PKU.
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Affiliation(s)
- Benedikt Sundermann
- Department of Clinical Radiology, Medical Faculty - University of Muenster - and University Hospital Muenster, Muenster, Germany
| | - Stefan Garde
- Department of Clinical Radiology, Medical Faculty - University of Muenster - and University Hospital Muenster, Muenster, Germany
| | - Mahboobeh Dehghan Nayyeri
- Department of Clinical Radiology, Medical Faculty - University of Muenster - and University Hospital Muenster, Muenster, Germany.,Department of Psychosomatic Medicine and Psychotherapy, LVR Clinic, Medical Faculty of the Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany.,Department of Psychosomatic Medicine and Psychotherapy, University Hospital Muenster, Muenster, Germany
| | - Josef Weglage
- Department of General Pediatrics, University Hospital Muenster, Muenster, Germany
| | - Johanna Rau
- Department of Clinical Radiology, Medical Faculty - University of Muenster - and University Hospital Muenster, Muenster, Germany.,Department of Neurology, University Hospital Muenster, Muenster, Germany
| | - Bettina Pfleiderer
- Department of Clinical Radiology, Medical Faculty - University of Muenster - and University Hospital Muenster, Muenster, Germany.,Otto Creutzfeldt Center for Cognitive and Behavioral Neuroscience, Muenster, Germany
| | - Reinhold Feldmann
- Department of General Pediatrics, University Hospital Muenster, Muenster, Germany
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Neuropsychological Profile of Children with Early and Continuously Treated Phenylketonuria: Systematic Review and Future Approaches. J Int Neuropsychol Soc 2019; 25:624-643. [PMID: 31030702 DOI: 10.1017/s1355617719000146] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
OBJECTIVE To provide a comprehensive systematic review of the literature by examining studies published on all cognitive aspects of children with early and continuously treated phenylketonuria (ECT-PKU) included in the databases Medline, PsycINFO, and PsycARTICLE. METHOD In addition to a classical approach, we summarized methodology and results of each study in order to discuss current theoretical and methodological issues. We also examined recent advances in biochemical markers and treatments of PKU, with implications for future research on metabolic control and its role as a determinant of neuropsychological outcome. RESULTS Consistent with previous reviews, the hypothesis of a specific and central executive impairment in children with ECT-PKU was suggested. However, findings are inconclusive regarding the nature of executive impairments as well as their specificity, impact on everyday life, persistence over time, and etiology. CONCLUSION Given the current state of the science, we suggest future directions for research that utilizes a developmental and integrative approach to examine the effects of recent advances in biochemical markers and treatment of PKU. (JINS, 2019, 25, 624-643).
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Stevenson MP, Dewhurst R, Schilhab T, Bentsen P. Cognitive Restoration in Children Following Exposure to Nature: Evidence From the Attention Network Task and Mobile Eye Tracking. Front Psychol 2019; 10:42. [PMID: 30804825 PMCID: PMC6370667 DOI: 10.3389/fpsyg.2019.00042] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Accepted: 01/08/2019] [Indexed: 01/09/2023] Open
Abstract
Exposure to nature improves cognitive performance through a process of cognitive restoration. However, few studies have explored the effect in children, and no studies have explored how eye movements “in the wild” with mobile eye tracking technology contribute to the restoration process. Our results demonstrated that just a 30-min walk in a natural environment was sufficient to produce a faster and more stable pattern of responding on the Attention Network Task, compared with an urban environment. Exposure to the natural environment did not improve executive (directed) attention performance. This pattern of results supports suggestions that children and adults experience unique cognitive benefits from nature. Further, we provide the first evidence of a link between cognitive restoration and the allocation of eye gaze. Participants wearing a mobile eye-tracker exhibited higher fixation rates while walking in the natural environment compared to the urban environment. The data go some way in uncovering the mechanisms sub-serving the restoration effect in children and elaborate how nature may counteract the effects of mental fatigue.
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Affiliation(s)
- Matt P Stevenson
- Center for Outdoor Recreation and Education, University of Copenhagen, Copenhagen, Denmark
| | | | | | - Peter Bentsen
- Center for Outdoor Recreation and Education, University of Copenhagen, Copenhagen, Denmark.,Health Promotion Research, Steno Diabetes Center Copenhagen, Gentofte, Denmark
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McDermott JM, Pears KC, Bruce J, Kim HK, Roos L, Yoerger KL, Fisher PA. Improving kindergarten readiness in children with developmental disabilities: Changes in neural correlates of response monitoring. APPLIED NEUROPSYCHOLOGY. CHILD 2018; 7:187-199. [PMID: 28631968 PMCID: PMC6774671 DOI: 10.1080/21622965.2017.1286239] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Among children diagnosed with developmental delays, difficulties in self-regulation are prominent and have been linked to school readiness problems. The current study sought to examine the impact of the Kids in Transition to School (KITS) school readiness intervention program on self-regulation, with a specific focus on response monitoring skills, among children with developmental delays. Children (n = 20 in the KITS group and n = 21 in a services as usual group) were administered a flanker task during which event-related potential data were collected to examine group differences in response monitoring. Findings indicated that children in the KITS group showed significant enhancement of a neural index of response monitoring post-intervention. Specifically, the KITS group showed a significant change in the magnitude of their feedback-related negativity in response to negative performance feedback from baseline to post-intervention, whereas children in the services as usual group did not. There were no significant differences between the groups for the error-related negativity or the error-related positivity on incorrect trials nor were there group differences in behavioral performance on the task at the post-intervention assessment. Overall, these findings provide support for the plasticity of response monitoring skills in young children and support the growing literature demonstrating improved self-regulation outcomes via intervention that enhances children's response monitoring.
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Affiliation(s)
- Jennifer Martin McDermott
- Department of Psychological and Brain Sciences, University of Massachusetts, Amherst, Massachusetts, USA
| | | | | | - Hyoun K. Kim
- Oregon Social Learning Center, Eugene, Oregon, USA
| | - Leslie Roos
- Department of Psychology, University of Oregon, Eugene, Oregon, USA
| | | | - Philip A. Fisher
- Department of Psychology, University of Oregon, Eugene, Oregon, USA
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8
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A comparison of phenylketonuria with attention deficit hyperactivity disorder: do markedly different aetiologies deliver common phenotypes? Brain Res Bull 2013; 99:63-83. [PMID: 24140048 DOI: 10.1016/j.brainresbull.2013.10.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2013] [Revised: 09/04/2013] [Accepted: 10/07/2013] [Indexed: 01/21/2023]
Abstract
Phenylketonuria (PKU) is a well-defined metabolic disorder arising from a mutation that disrupts phenylalanine metabolism and so produces a variety of neural changes indirectly. Severe cognitive impairment can be prevented by dietary treatment; however, residual symptoms may be reported. These residual symptoms appear to overlap a more prevalent childhood disorder: Attention Deficit/Hyperactivity Disorder (ADHD). However, the aetiology of ADHD is a vast contrast to PKU: it seems to arise from a complex combination of genes; and it has a substantial environmental component. We ask whether these two disorders result from two vastly different genotypes that converge on a specific core phenotype that includes similar dysfunctions of Gray's (Gray, 1982) Behavioural Inhibition System (BIS), coupled with other disorder-specific dysfunctions. If so, we believe comparison of the commonalities will allow greater understanding of the neuropsychology of both disorders. We review in detail the aetiology, treatment, neural pathology, cognitive deficits and electrophysiological abnormalities of PKU; and compare this with selected directly matching aspects of ADHD. The biochemical and neural pathologies of PKU and ADHD are quite distinct in their causes and detail; but they result in the disorder in the brain of large amino acid levels, dopamine and white matter that are very similar and could explain the overlap of symptoms within and between the PKU and ADHD spectra. The common deficits affect visual function, motor function, attention, working memory, planning, and inhibition. For each of PKU and ADHD separately, a subset of deficits has been attributed to a primary dysfunction of behavioural inhibition. In the case of ADHD (excluding the inattentive subtype) this has been proposed to involve a specific failure of the BIS; and we suggest that this is also true of PKU. This accounts for a substantial proportion of the parallels in the superficial symptoms of both disorders and we see this as linked to prefrontal, rather than more general, dysfunction of the BIS.
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9
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Johnstone SJ, Barry RJ, Clarke AR. Ten years on: a follow-up review of ERP research in attention-deficit/hyperactivity disorder. Clin Neurophysiol 2012; 124:644-57. [PMID: 23063669 DOI: 10.1016/j.clinph.2012.09.006] [Citation(s) in RCA: 118] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2012] [Revised: 09/03/2012] [Accepted: 09/10/2012] [Indexed: 11/28/2022]
Abstract
This article reviews the event-related potential (ERP) literature in relation to attention-deficit/hyperactivity disorder (AD/HD) over the years 2002-2012. ERP studies exploring various aspects of brain functioning in children and adolescents with AD/HD are reviewed, with a focus on group effects and interpretations in the domains of attention, inhibitory control, performance monitoring, non-pharmacological treatments, and ERP/energetics interactions. There has been a distinct shift in research intensity over the past 10 years, with a large increase in ERP studies conducted in the areas of inhibitory control and performance monitoring. Overall, the research has identified a substantial number of ERP correlates of AD/HD. Robust differences from healthy controls have been reported in early orienting, inhibitory control, and error-processing components. These data offer potential to improve our understanding of the specific brain dysfunction(s) which contribute to the disorder. The literature would benefit from a more rigorous approach to clinical group composition and consideration of age effects, as well as increased emphasis on replication and extension studies using exacting participant, task, and analysis parameters.
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Sokhadze EM, Baruth JM, Sears L, Sokhadze GE, El-Baz AS, Williams E, Klapheke R, Casanova MF. EVENT-RELATED POTENTIAL STUDY OF ATTENTION REGULATION DURING ILLUSORY FIGURE CATEGORIZATION TASK IN ADHD, AUTISM SPECTRUM DISORDER, AND TYPICAL CHILDREN. JOURNAL OF NEUROTHERAPY 2012; 16:12-31. [PMID: 23329879 PMCID: PMC3544080 DOI: 10.1080/10874208.2012.650119] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Autism spectrum disorders (ASD) and attention deficit/hyperactivity disorder (ADHD) are very common developmental disorders which share some similar symptoms of social, emotional, and attentional deficits. This study is aimed to help understand the differences and similarities of these deficits using analysis of dense-array event-related potentials (ERP) during an illusory figure recognition task. Although ADHD and ASD seem very distinct, they have been shown to share some similarities in their symptoms. Our hypothesis was that children with ASD will show less pronounced differences in ERP responses to target and non-target stimuli as compared to typical children, and to a lesser extent, ADHD. Participants were children with ASD (N=16), ADHD (N=16), and controls (N=16). EEG was collected using a 128 channel EEG system. The task involved the recognition of a specific illusory shape, in this case a square or triangle, created by three or four inducer disks. There were no between group differences in reaction time (RT) to target stimuli, but both ASD and ADHD committed more errors, specifically the ASD group had statistically higher commission error rate than controls. Post-error RT in ASD group was exhibited in a post-error speeding rather than corrective RT slowing typical for the controls. The ASD group also demonstrated an attenuated error-related negativity (ERN) as compared to ADHD and controls. The fronto-central P200, N200, and P300 were enhanced and less differentiated in response to target and non-target figures in the ASD group. The same ERP components were marked by more prolonged latencies in the ADHD group as compared to both ASD and typical controls. The findings are interpreted according to the "minicolumnar" hypothesis proposing existence of neuropathological differences in ASD and ADHD, specifically minicolumnar number/width morphometry spectrum differences. In autism, a model of local hyperconnectivity and long-range hypoconnectivity explains many of the behavioral and cognitive deficits present in the condition, while the inverse arrangement of local hypoconnectivity and long-range hyperconnectivity in ADHD explains some deficits typical for this disorder. The current ERP study supports the proposed suggestion that some between group differences could be manifested in the frontal ERP indices of executive functions during performance on an illusory figure categorization task.
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Affiliation(s)
- Estate M Sokhadze
- Psychiatry & Behavioral Sciences, University of Louisville, Louisville, KY ; Bioengineering, University of Louisville, Louisville, KY
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van der Meere JJ, Shalev RS, Borger N, Wiersema JR. Methylphenidate, interstimulus interval, and reaction time performance of children with attention deficit/hyperactivity disorder: a pilot study. Child Neuropsychol 2012; 15:554-66. [PMID: 19296298 DOI: 10.1080/09297040902758803] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Thirteen children with attention deficit/hyperactivity disorder (ADHD: DSM-IV-TR) participated in the pilot study. They carried out a Go/No-Go test with a short (2 seconds) and long (6 seconds) interstimulus interval (ISI) when on placebo and a therapeutic dose of methylphenidate (MPH). For the long-ISI placebo condition the responses were slow and inaccurate. This pattern of response may be due to underactivation of the readiness-to-respond state that is not fully controlled by effort allocation. Speed of response and accuracy were enhanced during the short-ISI placebo condition and the long-ISI MPH condition. However, the combined effect (short ISI and MPH) resulted in a fast but inaccurate response style. This pattern of response may be due to overactivation of the readiness-to-respond state. The data of the pilot study support the stimulus shift hypothesis: MPH administration result in deterioration on tests on which children had previously done well (short ISI plus placebo versus short ISI plus MPH). In addition, the data support the idea that ADHD is associated with poor state regulation rather than motivational (delay aversion) theories or temporal-processing/time-estimation theories of ADHD. The pilot study defined empirically an issue for further study with the larger controlled sample.
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Affiliation(s)
- J J van der Meere
- Department of Clinical and Developmental Psychology, Groningen, The Netherlands.
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12
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Sundermann B, Pfleiderer B, Möller HE, Schwindt W, Weglage J, Lepsien J, Feldmann R. Tackling frontal lobe-related functions in PKU through functional brain imaging: a Stroop task in adult patients. J Inherit Metab Dis 2011; 34:711-21. [PMID: 21491106 DOI: 10.1007/s10545-011-9318-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2010] [Revised: 02/28/2011] [Accepted: 03/18/2011] [Indexed: 12/26/2022]
Abstract
BACKGROUND Profound mental retardation in phenylketonuria (PKU) can be prevented by a low phenylalanine (Phe) diet. However, even patients treated early have inconsistently shown deficits in several frontal lobe-related neuropsychological tasks such as the widely accepted Stroop task. The goal of this study was to investigate whether adult patients exhibit altered brain activation in Stroop-related locations in comparison to healthy controls and if an acute increase in blood Phe levels in patients has an effect on activation patterns. METHODS Seventeen male, early-treated patients with classic PKU (mean ± SD age: 31.0 ± 5.2 years) and 15 male healthy controls (32.1 ± 6.4 years) were compared using a color-word matching Stroop task in a functional magnetic resonance imaging (fMRI) study at 3T. Participants were scanned twice, and an oral Phe load (100 mg/kg body weight) was administered to patients prior to one of the fMRI sessions (placebo-controlled). Activity in brain regions that are known to be involved in Stroop tasks was assessed. RESULTS PKU patients exhibited poorer accuracy in incongruent trials. Reaction times were not significantly different. There were no consistent differences in BOLD activations in Stroop-associated brain regions. The oral Phe administration had no significant effect on brain activity. CONCLUSIONS Neither a generally slower task performance nor distinctively altered functioning of brain networks involved in a task representing a subset of dopamine-dependent executive functions could be proven. Decreased accuracy and inconsistent findings in posterior areas necessitate further study of frontal-lobe functioning in PKU patients in larger study samples.
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Affiliation(s)
- Benedikt Sundermann
- Department of Clinical Radiology, University Hospital Muenster, Albert-Schweitzer-Str. 33, 48149 Muenster, Germany
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van Spronsen FJ, Huijbregts SCJ, Bosch AM, Leuzzi V. Cognitive, neurophysiological, neurological and psychosocial outcomes in early-treated PKU-patients: a start toward standardized outcome measurement across development. Mol Genet Metab 2011; 104 Suppl:S45-51. [PMID: 22018724 DOI: 10.1016/j.ymgme.2011.09.036] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2011] [Revised: 09/28/2011] [Accepted: 09/29/2011] [Indexed: 11/23/2022]
Abstract
The aim of this paper is to provide a concise summary of findings from outcome studies in early-treated phenylketonuria (PKU). The paper should not be considered as an extensive review of the many different outcome measures that have been used in PKU-research, but as an attempt to integrate such findings so that they will be of additional value for day to day monitoring of PKU-patients and may direct future research to fill the present gaps of knowledge. Neurological, neuropsychological, neurophysiological, neuroimaging, quality of life, and psychosocial findings will be discussed in the context of their potential contributions to lifelong follow-up and treatment of PKU-patients being summarized in statements.
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Affiliation(s)
- F J van Spronsen
- Section of Metabolic Diseases, Beatrix Children's Hospital, University Medical Center of Groningen, University of Groningen, Groningen, The Netherlands.
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14
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Enns GM, Koch R, Brumm V, Blakely E, Suter R, Jurecki E. Suboptimal outcomes in patients with PKU treated early with diet alone: revisiting the evidence. Mol Genet Metab 2010; 101:99-109. [PMID: 20678948 DOI: 10.1016/j.ymgme.2010.05.017] [Citation(s) in RCA: 128] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2010] [Revised: 05/27/2010] [Accepted: 05/28/2010] [Indexed: 11/22/2022]
Abstract
BACKGROUND The National Institute of Health (NIH) published a Consensus Statement on the screening and management of Phenylketonuria (PKU) in 2000. The panel involved in the development of this consensus statement acknowledged the lack of data regarding the potential for more subtle suboptimal outcomes and the need for further research into treatment options. In subsequent years, the approval of new treatment options for PKU and outcome data for patients treated from the newborn period by dietary therapy alone have become available. We hypothesized that a review of the PKU literature since 2000 would provide further evidence related to neurocognitive, psychosocial, and physical outcomes that could serve as a basis for reassessment of the 2000 NIH Consensus Statement. METHODS A systematic review of literature residing in PubMed, Scopus and PsychInfo was performed in order to assess the outcome data over the last decade in diet-alone early-treated PKU patients to assess the need for new recommendations and validity of older recommendations in light of new evidence. RESULTS The majority of publications (140/150) that contained primary outcome data presented at least one suboptimal outcome compared to control groups or standardized norms/reference values in at least one of the following areas: neurocognitive/psychosocial (N=60; 58 reporting suboptimal outcomes); quality of life (N=6; 4 reporting suboptimal outcomes); brain pathology (N=32; 30 reporting suboptimal outcomes); growth/nutrition (N=34; 29 reporting suboptimal outcomes); bone pathology (N=9; 9 reporting suboptimal outcomes); and/or maternal PKU (N=19; 19 reporting suboptimal outcomes). CONCLUSIONS Despite the remarkable success of public health programs that have instituted newborn screening and early introduction of dietary therapy for PKU, there is a growing body of evidence that suggests that neurocognitive, psychosocial, quality of life, growth, nutrition, bone pathology and maternal PKU outcomes are suboptimal. The time may be right for revisiting the 2000 NIH Consensus Statement in order to address a number of important issues related to PKU management, including treatment advancements for metabolic control in PKU, blood Phe variability, neurocognitive and psychological assessments, routine screening measures for nutritional biomarkers, and bone pathology.
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Affiliation(s)
- G M Enns
- Division of Medical Genetics, Department of Pediatrics, Lucile Packard Children's Hospital, Stanford University, Stanford, CA 94305-5208,USA.
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15
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Silva GKD, Lamônica DAC. Performance of children with phenylketonuria in the Developmental Screening Test--Denver II. PRO-FONO : REVISTA DE ATUALIZACAO CIENTIFICA 2010; 22:345-51. [PMID: 21103729 DOI: 10.1590/s0104-56872010000300031] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2009] [Accepted: 07/29/2010] [Indexed: 11/21/2022]
Abstract
BACKGROUND phenylketonuria is an autosomal recessive disorder resulting from the mutation of a gene located in chromosome 12q22-24.1. AIM to describe the performance of children with classic phenylketonuria, who were diagnosed and treated early, in the Development Screening Test Denver - II. METHOD participants were 20 children with phenylketonuria, ranging in age from 3 and 6 years, and 10 children with typical language development, paired by gender, age and socioeconomic level to the research group. The plasmatic phenylalanine measure and the neurological, psychological and social information were gathered in the data base of the Neonatal Screening Programs for Metabolic disorder. Assessment consisted on the application of the Development Screening Test Denver II. A descriptive statistical analysis and the Mann Whitney test were used in order to characterize the tested skills. For the measurements of the plasmatic phenylalanine blood levels the values considered for analysis were: below 2 mg/dL, above 4 mg/dL, reference values between 2 and 4 mg/dL, of all exams performed during the participants'lives; maximum and minimum values and values obtained on the day of the screening application. RESULTS comparison between the groups indicated statistically significant differences for the personal-social and language areas. CONCLUSION children who were diagnosed and treated early for phenylketonuria present deficits in the personal-social and language areas. Also, even when receiving follow-up and undergoing treatment, these children presented difficulties in maintaining normal plasmatic phenylalanine levels.
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Affiliation(s)
- Greyce Kelly da Silva
- Fonoaudióloga, Faculdade de Odontologia, Universidade de São Paulo de Bauru (FOB/USP), Brazil.
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16
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Kooistra L, van der Meere JJ, Edwards JD, Kaplan BJ, Crawford S, Goodyear BG. Preliminary fMRI findings on the effects of event rate in adults with ADHD. J Neural Transm (Vienna) 2010; 117:655-62. [DOI: 10.1007/s00702-010-0374-y] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2009] [Accepted: 01/27/2010] [Indexed: 10/19/2022]
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Kooistra L, Crawford S, Gibbard B, Ramage B, Kaplan BJ. Differentiating attention deficits in children with fetal alcohol spectrum disorder or attention-deficit-hyperactivity disorder. Dev Med Child Neurol 2010; 52:205-11. [PMID: 19549201 DOI: 10.1111/j.1469-8749.2009.03352.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
AIM The attention and inhibition problems found in children with attention-deficit-hyperactivity disorder (ADHD) are also common in children with fetal alcohol spectrum disorders (FASDs). Attempts to distinguish ADHD from FASDs in terms of these deficits are rare and were pursued in this study. METHOD A total of 116 children (47 with ADHD, 31 males, 16 females; 30 with FASDs, 17 males, 13 females; and 39 comparison children, 20 males, 19 females) participated. The mean age was 9 years 4 months (SD 1y 8mo) in the ADHD groups, 8 years 10 months (SD 1y 2mo) in the FASD group, and 9 years 1 month (SD 1y 1mo) in the comparison group. Sustained attention was tested with a slow event rate continuous performance task (CPT). Inhibitory control was tested with both a slow and fast event rate Go/No-Go task. RESULTS On the CPT task, children with ADHD, combined type (ADHD-C), ADHD, primarily inattentive type (ADHD-PI), and FASDs showed greater declines in task performance as a function of time than comparison children, suggesting sustained attention problems in all clinical groups. Children's Go/No-Go performance was event-rate dependent, with the ADHD-C group being affected in the slow condition and the ADHD-PI and FASD groups having problems with the fast condition. INTERPRETATION Children with ADHD-C are typically impaired in handling understimulation, while children with FASDs may have problems with overstimulation. The dissociation in responsivity to event rate between groups may have significant differential diagnostic value.
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Affiliation(s)
- Libbe Kooistra
- Department of Pediatrics, University of Calgary, Calgary, Alberta, Canada.
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18
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van der Meere J, Börger NA, Potgieter ST, Pirila S, De Cock P. Very Low Birth Weight and Attention Deficit/Hyperactivity Disorder. Child Neuropsychol 2009; 15:605-18. [DOI: 10.1080/09297040902984482] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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19
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Sonuga-Barke EJS, Wiersema JR, van der Meere JJ, Roeyers H. Context-dependent Dynamic Processes in Attention Deficit/Hyperactivity Disorder: Differentiating Common and Unique Effects of State Regulation Deficits and Delay Aversion. Neuropsychol Rev 2009; 20:86-102. [DOI: 10.1007/s11065-009-9115-0] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2009] [Accepted: 08/17/2009] [Indexed: 11/30/2022]
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20
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Araujo GC, Christ SE, Steiner RD, Grange DK, Nardos B, McKinstry RC, White DA. Response monitoring in children with phenylketonuria. Neuropsychology 2009; 23:130-4. [PMID: 19210041 DOI: 10.1037/a0013488] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Phenylketonuria (PKU) is characterized by a disruption in the metabolism of phenylalanine and is associated with dopamine deficiency (Diamond, Prevor, Callender, & Druin, 1997) and cerebral white matter abnormalities (e.g., Anderson et al., 2007). From a neuropsychological perspective, prefrontal dysfunction is thought to underlie the deficits in executive abilities observed in individuals with PKU (Christ, Steiner, Grange, Abrams, & White, 2006; Diamond et al., 1997; White, Nortz, Mandernach, Huntington, & Steiner, 2001, 2002). The purpose of our study was to examine a specific aspect of executive ability, response monitoring, as measured by posterror slowing. The authors examined posterror reaction time (RT) in 24 children with well-controlled, early treated PKU and 25 typically developing control children using a go/no-go task. Results showed that RTs of both controls and children with PKU slowed significantly following the commission of errors. The magnitude of posterror slowing, however, was significantly less for children with PKU. These findings indicate deficient response monitoring in children with PKU.
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Affiliation(s)
- Gabriel C Araujo
- Department of Psychology, Washington University, St.Louis, MO 63130, USA
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21
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Johnson KA, Wiersema JR, Kuntsi J. What would Karl Popper say? Are current psychological theories of ADHD falsifiable? Behav Brain Funct 2009; 5:15. [PMID: 19257888 PMCID: PMC2654902 DOI: 10.1186/1744-9081-5-15] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2008] [Accepted: 03/03/2009] [Indexed: 01/01/2023] Open
Abstract
Attention Deficit Hyperactivity Disorder (ADHD) is a common and highly heritable neurodevelopmental psychiatric disorder. Here, we critically review four major psychological theories of ADHD - the Executive Dysfunction, the State Regulation, the Delay Aversion and the Dynamic Developmental - on their abilities to explain all the symptoms of ADHD, their testability and their openness to falsification. We conclude that theoreticians should focus, to a greater extent than currently practiced, on developing refutable theories of ADHD.
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Affiliation(s)
- Katherine A Johnson
- School of Psychology and Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin 2, Ireland.
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22
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Neuropsychological speed tests and blood phenylalanine levels in patients with phenylketonuria: A meta-analysis. Neurosci Biobehav Rev 2009; 33:414-21. [DOI: 10.1016/j.neubiorev.2008.11.001] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2008] [Revised: 10/31/2008] [Accepted: 11/01/2008] [Indexed: 11/18/2022]
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23
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Arousal-state modulation in children with AD/HD. Clin Neurophysiol 2009; 120:30-40. [DOI: 10.1016/j.clinph.2008.09.026] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2008] [Revised: 09/22/2008] [Accepted: 09/29/2008] [Indexed: 11/23/2022]
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Carrion VG, Garrett A, Menon V, Weems CF, Reiss AL. Posttraumatic stress symptoms and brain function during a response-inhibition task: an fMRI study in youth. Depress Anxiety 2008; 25:514-26. [PMID: 17598145 DOI: 10.1002/da.20346] [Citation(s) in RCA: 134] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Youth who experience interpersonal trauma and have posttraumatic stress symptoms (PTSS) can exhibit difficulties in executive function and physiological hyperarousal. Response inhibition has been identified as a core component of executive function. In this study, we investigate the functional neuroanatomical correlates of response inhibition in youth with PTSS. Thirty right-handed medication-naïve youth between the ages of 10 and 16 years underwent a 3-Tesla Functional Magnetic Resonance Imaging scan during a response-inhibition (Go/No-Go) task. Youth with PTSS (n = 16) were age and gender matched to a control group of healthy youth (n = 14). Between-groups analyses were conducted to identify brain regions of greater activation in the No/Go-Go contrasts. PTSS and control youth performed the task with similar accuracy and response times. Control subjects had greater middle frontal cortex activation when compared with PTSS subjects. PTSS subjects had greater medial frontal activation when compared with control subjects. A sub-group of youth with PTSS and a history of self-injurious behaviors demonstrated increased insula and orbitofrontal activation when compared with those PTSS youth with no self-injurious behaviors. Insula activation correlated positively with PTSS severity. Diminished middle frontal activity and enhanced medial frontal activity during response-inhibition tasks may represent underlying neurofunctional markers of PTSS.
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Affiliation(s)
- Victor G Carrion
- Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, California 94305-5719, USA.
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25
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Raymaekers R, Antrop I, van der Meere JJ, Wiersema JR, Roeyers H. HFA and ADHD: A direct comparison on state regulation and response inhibition. J Clin Exp Neuropsychol 2007; 29:418-27. [PMID: 17497565 DOI: 10.1080/13803390600737990] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
This study examined whether children with high-functioning autism (HFA) are easily overaroused/activated and whether children with attention-deficit/hyperactivity disorder (ADHD) are easily underaroused/activated. This double dissociation was tested using a go/no-go paradigm with computer-paced fast and slow conditions and a self-paced condition. In the HFA group, a performance decline in the fast condition and slow performance in the self-paced condition were expected. In the ADHD group, a performance decline in the slow condition and fast performance in the self-paced condition were expected. No difference was found between groups for state regulation and response inhibition. Findings are discussed in the light of development, comorbidity, and subtypes.
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Affiliation(s)
- R Raymaekers
- Department of Experimental, Clinical and Health Psychology, Ghent University, Ghent, Belgium.
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Russell VA, Oades RD, Tannock R, Killeen PR, Auerbach JG, Johansen EB, Sagvolden T. Response variability in Attention-Deficit/Hyperactivity Disorder: a neuronal and glial energetics hypothesis. Behav Brain Funct 2006; 2:30. [PMID: 16925830 PMCID: PMC1624838 DOI: 10.1186/1744-9081-2-30] [Citation(s) in RCA: 167] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2006] [Accepted: 08/23/2006] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND Current concepts of Attention-Deficit/Hyperactivity Disorder (ADHD) emphasize the role of higher-order cognitive functions and reinforcement processes attributed to structural and biochemical anomalies in cortical and limbic neural networks innervated by the monoamines, dopamine, noradrenaline and serotonin. However, these explanations do not account for the ubiquitous findings in ADHD of intra-individual performance variability, particularly on tasks that require continual responses to rapid, externally-paced stimuli. Nor do they consider attention as a temporal process dependent upon a continuous energy supply for efficient and consistent function. A consideration of this feature of intra-individual response variability, which is not unique to ADHD but is also found in other disorders, leads to a new perspective on the causes and potential remedies of specific aspects of ADHD. THE HYPOTHESIS We propose that in ADHD, astrocyte function is insufficient, particularly in terms of its formation and supply of lactate. This insufficiency has implications both for performance and development: H1) In rapidly firing neurons there is deficient ATP production, slow restoration of ionic gradients across neuronal membranes and delayed neuronal firing; H2) In oligodendrocytes insufficient lactate supply impairs fatty acid synthesis and myelination of axons during development. These effects occur over vastly different time scales: those due to deficient ATP (H1) occur over milliseconds, whereas those due to deficient myelination (H2) occur over months and years. Collectively the neural outcomes of impaired astrocytic release of lactate manifest behaviourally as inefficient and inconsistent performance (variable response times across the lifespan, especially during activities that require sustained speeded responses and complex information processing). TESTING THE HYPOTHESIS Multi-level and multi-method approaches are required. These include: 1) Use of dynamic strategies to evaluate cognitive performance under conditions that vary in duration, complexity, speed, and reinforcement; 2) Use of sensitive neuroimaging techniques such as diffusion tensor imaging, magnetic resonance spectroscopy, electroencephalography or magnetoencephalopathy to quantify developmental changes in myelination in ADHD as a potential basis for the delayed maturation of brain function and coordination, and 3) Investigation of the prevalence of genetic markers for factors that regulate energy metabolism (lactate, glutamate, glucose transporters, glycogen synthase, glycogen phosphorylase, glycolytic enzymes), release of glutamate from synaptic terminals and glutamate-stimulated lactate production (SNAP25, glutamate receptors, adenosine receptors, neurexins, intracellular Ca2+), as well as astrocyte function (alpha1, alpha2 and beta-adrenoceptors, dopamine D1 receptors) and myelin synthesis (lactate transporter, Lingo-1, Quaking homolog, leukemia inhibitory factor, and Transferrin). IMPLICATIONS OF THE HYPOTHESIS The hypothesis extends existing theories of ADHD by proposing a physiological basis for specific aspects of the ADHD phenotype - namely frequent, transient and impairing fluctuations in functioning, particularly during performance of speeded, effortful tasks. The immediate effects of deficient ATP production and slow restoration of ionic gradients across membranes of rapidly firing neurons have implications for daily functioning: For individuals with ADHD, performance efficacy would be enhanced if repetitive and lengthy effortful tasks were segmented to reduce concurrent demands for speed and accuracy of response (introduction of breaks into lengthy/effortful activities such as examinations, motorway driving, assembly-line production). Also, variations in task or modality and the use of self- rather than system-paced schedules would be helpful. This would enable energetic demands to be distributed to alternate neural resources, and energy reserves to be re-established. Longer-term effects may manifest as reduction in regional brain volumes since brain areas with the highest energy demand will be most affected by a restricted energy supply and may be reduced in size. Novel forms of therapeutic agent and delivery system could be based on factors that regulate energy production and myelin synthesis. Since the phenomena and our proposed basis for it are not unique to ADHD but also manifests in other disorders, the implications of our hypotheses may be relevant to understanding and remediating these other conditions as well.
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Affiliation(s)
- Vivienne A Russell
- Department of Human Biology, Faculty of Health Sciences, University of Cape Town, Anzio Road, Observatory 7925, South Africa
| | - Robert D Oades
- University Clinic for Child and Adolescent Psychiatry, Virchowstr. 174, 45147 Essen, Germany
| | - Rosemary Tannock
- Research Institute of The Hospital for Sick Children, University of Toronto, Canada
| | - Peter R Killeen
- Department of Psychology, Arizona State University, Tempe, AZ 85287-1104, USA
| | - Judith G Auerbach
- Department of Behavioural Sciences, Ben-Gurion University, Beer Sheva, 84105, Israel
| | - Espen B Johansen
- Department of Physiology, University of Oslo, N-0317 Oslo, Norway
| | - Terje Sagvolden
- Department of Physiology, University of Oslo, N-0317 Oslo, Norway
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27
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Kuntsi J, Andreou P, Ma J, Börger NA, van der Meere JJ. Testing assumptions for endophenotype studies in ADHD: reliability and validity of tasks in a general population sample. BMC Psychiatry 2005; 5:40. [PMID: 16262903 PMCID: PMC1291376 DOI: 10.1186/1471-244x-5-40] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2005] [Accepted: 11/01/2005] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Advances in both genetic and cognitive-experimental studies on attention deficit hyperactivity disorder (ADHD) have opened new opportunities for cognitive endophenotype research. In such genetic designs the focus is on individual differences in characteristics, associated with ADHD, that can be measured reliably over time. Genetic studies that take a 'quantitative trait loci' approach hypothesise that multiple susceptibility genes contribute to a continuous dimension of ADHD symptoms. As an important initial step, we aimed to investigate the underlying assumptions that (1) key cognitive-experimental tasks indicate adequate test-retest reliability and (2) ADHD symptom scores in a general population sample are associated with performance on these tasks. METHODS Forty-nine children were assessed on a go/no-go task and a reaction time task (the 'fast task') that included manipulations with event rate and incentives. The children were assessed twice, with a test-retest interval of two weeks. RESULTS The majority of the task variables demonstrated moderate-to-good test-retest reliability. The correlations between teacher ratings of ADHD symptoms and key task variables were .4-.6: ADHD symptoms were associated with poor performance (especially high reaction time variability) in a slow baseline condition, whereas there was low or no association in conditions with a faster event rate or incentives. In contrast, no clear pattern of findings emerged based on parent ratings of ADHD symptoms. CONCLUSION The data support the usefulness of the go/no-go and fast tasks for genetic studies, which require reliable and valid indices of individual differences. The overall pattern of associations between teacher ratings of ADHD symptoms and task variables is consistent with effects of event rate and incentives on performance, as predicted by the model of activation and arousal regulation. The lack of a clear pattern of findings with parent ratings of ADHD symptoms warrants further study.
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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
| | - Penny Andreou
- MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, King's College London, De Crespigny Park, London SE5 8AF, UK
| | - Jonathan Ma
- MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, King's College London, De Crespigny Park, London SE5 8AF, UK
| | - Norbert A Börger
- Department of Developmental and Experimental Clinical Psychology, University of Groningen, Grote Kruisstraat 2/1, 9712 TS Groningen, The Netherlands
| | - Jaap J van der Meere
- Department of Developmental and Experimental Clinical Psychology, University of Groningen, Grote Kruisstraat 2/1, 9712 TS Groningen, The Netherlands
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