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Wandin H, Lindberg P, Sonnander K. Aided language modelling, responsive communication and eye-gaze technology as communication intervention for adults with Rett syndrome: three experimental single case studies. Disabil Rehabil Assist Technol 2023; 18:1011-1025. [PMID: 34455895 DOI: 10.1080/17483107.2021.1967469] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Accepted: 08/09/2021] [Indexed: 10/20/2022]
Abstract
PURPOSE To examine the effect of a communication intervention package on expressive communication and visual attention in individuals with Rett syndrome. MATERIALS AND METHODS A modified withdrawal (A-B1-A1-B2-A2) single case experimental design with a direct inter-subject replication across three participants was applied. Three women with Rett syndrome participated. The study took place over a six-week period and comprised 32 sessions with each participant. All sessions were video recorded. During the intervention the communication partner used aided language modelling on a gaze-controlled device in combination with using responsive partner strategies. Expressive communication was assessed as synthesised words per minute and unique synthesised words per minute. Visual attention was assessed as rate of focused gazes (1 s or longer) in interaction. RESULTS An intervention effect was found on the rate of unique words for all participants. The rate of words increased for two participants when the intervention was introduced but no withdrawal effect could be seen. An intervention effect on visual attention could be seen for one participant. The intervention appeared to have social validity as reported by caregivers. CONCLUSION Aided language modelling (ALM), while using responsive partner strategies and a gaze-controlled device may be used with adult individuals with Rett syndrome to increase their rate of expressive communication. Detailed observational measures revealed individual learning patterns, which may provide clinically valuable insights.Implications for RehabilitationAdults with Rett syndrome may benefit from access to gaze-controlled devices in combination with responsive partner strategies.Responsive partner communication may be effective for some individuals with Rett syndrome to increase their rate of synthesised utterances.Rate of focused gazes may be considered as an outcome measure for individuals with oculomotor difficulties when introducing aided language modelling.
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Affiliation(s)
- H Wandin
- Department of Public Health and Caring Sciences, Research in Disability and Habilitation, Uppsala University, Uppsala, Sweden
- Swedish National Center for Rett Syndrome and Related Disorders, Region Jämtland Härjedalen, Frösön, Sweden
| | - P Lindberg
- Department of Psychology, Uppsala University, Uppsala, Sweden
| | - K Sonnander
- Department of Public Health and Caring Sciences, Research in Disability and Habilitation, Uppsala University, Uppsala, Sweden
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Dulz S, Schwering C, Wildner J, Spartalis C, Schuettauf F, Bartsch U, Wibbeler E, Nickel M, Spitzer MS, Atiskova Y, Schulz A. Ongoing retinal degeneration despite intraventricular enzyme replacement therapy with cerliponase alfa in late-infantile neuronal ceroid lipofuscinosis type 2 (CLN2 disease). Br J Ophthalmol 2023; 107:1478-1483. [PMID: 35772852 DOI: 10.1136/bjo-2022-321260] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Accepted: 06/11/2022] [Indexed: 11/04/2022]
Abstract
BACKGROUND/AIMS Late-infantile neuronal ceroid lipofuscinosis type 2 (CLN2) is a neurodegenerative, blinding lysosomal storage disorder. The purpose of the current study was to characterise the progression of CLN2-associated retinal degeneration in patients under intraventricular enzyme replacement therapy (ERT) with cerliponase alfa. METHODS We analysed visual function, retinal morphology and neuropaediatric data using preferential looking test (PLT), Weill Cornell Batten Scale (WCBS), optical coherence tomography (OCT) imaging and the Hamburg Motor-Language late-infantile neuronal ceroid lipofuscinosis (LINCL) Scale (M-L scale). RESULTS Fifty-six eyes of 28 patients had baseline PLT, WCBS and OCT. 15 patients underwent serial examinations, resulting in a total of 132 OCT scans and WCBS results, 66 Hamburg M-L scores and 49 PLT results during a mean follow-up time of 18.2 months (range 5-40). A negative correlation (r=-0.69, p<0.001) was found between central retinal thickness (CRT) values and age at examination with a maximal annual decrease of 23 µm between 56 and 80 months of age. A significant correlation was observed between PLT results and the age at examination (r=0.46, p=0.001), the WCBS scores (r=0.62; p<0.001) and CRT values (r=-0.64; p<0.001). The M-L score correlated with the ocular measurements (CRT: r=0.58, p<0.001; WCBS r=-0.64, p<0.001; PLT score: r=-0.57, p<0.001). CONCLUSION Despite intraventricular ERT, retinal degeneration progressed in patients with CLN2 and was particularly pronounced between 56 and 80 months of age. Retina-directed therapies should therefore be initiated before or as early as possible during the phase of rapid retinal degeneration. PLT and WCBS were identified as valuable outcome measures to monitor disease progression. TRIAL REGISTRATION NUMBER NCT04613089.
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Affiliation(s)
- Simon Dulz
- Department of Ophthalmology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - C Schwering
- Department of Pediatrics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Jan Wildner
- Department of Ophthalmology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Christoph Spartalis
- Department of Ophthalmology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Frank Schuettauf
- Department of Ophthalmology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Udo Bartsch
- Department of Ophthalmology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Eva Wibbeler
- Department of Pediatrics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Miriam Nickel
- Department of Pediatrics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Martin Stephan Spitzer
- Department of Ophthalmology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Yevgeniya Atiskova
- Department of Ophthalmology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Angela Schulz
- Department of Pediatrics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
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Familiar-Lopez I, Sikorskii A, Chhaya R, Holmes A, Arima EG, Caesar OJ, Nakasujja N, Boivin MJ. Predictive validation of Ugandan infant eye-tracking test for memory of human faces. Child Neuropsychol 2023; 29:486-502. [PMID: 35867478 DOI: 10.1080/09297049.2022.2099537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
We provide initial evidence that an eye-tracking based measure of infant attention and working memory (gaze preference for novel human faces) can predict aspects of neurocognitive performance years later among Ugandan children. 49 HIV-exposed/uninfected Ugandan children (22 boys, 27 girls) 6-12 months old were tested with the Mullen Scales of Early Learning and a modified Fagan Test of Infant Intelligence (FTII). Modified FTII measures pertaining to attention are correlated to the KABC-II Mental Processing Index (MPI) (rp = -0.40), p Cognitive assessments adapted to eye-tracking instrumentation can be useful to evaluate attention and working memory in HIV-affected children living in low- and middle-income countries.
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Affiliation(s)
- Itziar Familiar-Lopez
- Department of Psychiatry, College of Osteopathic Medicine, Michigan State University, East Lansing, MI, USA.,School of Public Health, University of Michigan, Ann Arbor, MI, USA
| | - Alla Sikorskii
- Department of Psychiatry, College of Osteopathic Medicine, Michigan State University, East Lansing, MI, USA
| | - Ronak Chhaya
- College of Human Medicine, Michigan State University, East Lansing, MI, USA
| | - Aatirah Holmes
- College of Human Medicine, Michigan State University, East Lansing, MI, USA
| | | | | | - Noeline Nakasujja
- Department of Psychiatry, College of Health Sciences, Makerere University, Kampala, Uganda
| | - Michael J Boivin
- Department of Psychiatry, College of Osteopathic Medicine, Michigan State University, East Lansing, MI, USA.,Department of Neurology & Ophthalmology, Michigan State University, East Lansing, MI, USA.,Department of Psychiatry, University of Michigan, Ann Arbor, MI, USA
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Shaheen G, Fleischman D. A case of JOAG in a patient with Rett syndrome. Am J Ophthalmol Case Rep 2023; 29:101762. [DOI: 10.1016/j.ajoc.2022.101762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 11/16/2022] [Accepted: 11/26/2022] [Indexed: 12/05/2022] Open
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Gómez Taibo ML, Paramos Alonso S. Documentación de habilidades comunicativas y de lenguaje receptivo en un caso de Síndrome de Rett. REVISTA DE INVESTIGACIÓN EN LOGOPEDIA 2022. [DOI: 10.5209/rlog.77431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Las dificultades de las personas con síndrome de Rett (SR) para hablar y producir respuestas motoras hace de la valoración un proceso difícil, resultando necesario combinar métodos informales y adaptaciones en los instrumentos formales para obtener información sobre los niveles de competencia. El objetivo de este estudio es documentar el proceso de valoración de las habilidades comunicativo-lingüísticas seguido con una niña con SR combinando métodos de evaluación y realizando adaptaciones en los tests estandarizados. Se llevaron a cabo observaciones informales en entornos naturales, los compañeros de comunicación cubrieron la Matriz de Comunicación, y se realizaron adaptaciones en los tests Vocabulario en Imágenes Peabody y TSA de desarrollo de la morfosintaxis, y en el Test of Aided Communication Performance, consistentes en reducir el número de alternativas, presentarlas en una disposición accesible a la señalización con la mirada, y en dar tiempo de espera para la respuesta de la participante con SR. Los resultados obtenidos mediante las adaptaciones utilizando la mirada como método de acceso mostraron niveles de dominio de comunicación preintencional y de comunicación no convencional, junto con destrezas emergentes en comunicación convencional y simbólica para funciones de petición e interacción social y una comprensión de estructuras gramaticales sencillas. La conclusión que se desprende es que es imperativo que las evaluaciones se adapten a las limitaciones físicas y orales de las personas con SR, de modo que puedan descubrirse capacidades ocultas, se establezcan objetivos para la intervención basados en sus niveles reales de competencia para apoyar al máximo la comunicación.
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Ward C, Chiat S, Townend GS. A comparison of formal and informal methods for assessing language and cognition in children with Rett syndrome. RESEARCH IN DEVELOPMENTAL DISABILITIES 2021; 114:103961. [PMID: 33915382 DOI: 10.1016/j.ridd.2021.103961] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 03/25/2021] [Accepted: 04/20/2021] [Indexed: 06/12/2023]
Abstract
BACKGROUND Opinions about the cognitive and receptive language skills of people with Rett syndrome (RTT) range from severe intellectual impairment to near-normal development. Assessment is challenging because most are non-verbal, with no purposeful hand use. Clarkson et al. (2017) adapted the Mullen Scales of Early Learning for use with eye gaze technology (MSEL-A/ET) for people with RTT. AIMS To investigate and compare the performance of children with RTT on formal and newly-designed informal assessments of language and cognition using eye gaze/tracking technology. METHODS AND PROCEDURES Ten children with RTT aged 4:0-6:8 were assessed on the MSEL-A/ET for Visual Reception (VR) and Receptive Language (RL), and standard MSEL for Expressive Language (EL). Informal assessments of the same skills were embedded in activities such as reading and cake-decorating. OUTCOMES AND RESULTS Standard scores on MSEL-A/ET VR and RL subtests ranged from 'very low' to 'above average'. All children scored 'very low' on standard EL assessment. Informal assessments added information about EL, with children producing 1-3 word utterances and a range of communicative functions through an eye gaze device. CONCLUSIONS AND IMPLICATIONS Combining low-tech augmentative and alternative communication, eye gaze technology, informal activities and formal assessment, yields greater insight into children's abilities. This is important in informing suitable support and education for the individual.
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Affiliation(s)
- Callie Ward
- School of Health Sciences, Language and Communication Science, City, University of London, Northampton Square, London, EC1V 0HB, UK; Rett UK, Victory House, Chobham Street, Luton, LU1 3BS, UK
| | - Shula Chiat
- School of Health Sciences, Language and Communication Science, City, University of London, Northampton Square, London, EC1V 0HB, UK
| | - Gillian S Townend
- Rett UK, Victory House, Chobham Street, Luton, LU1 3BS, UK; Rett Expertise Centre Netherlands-GKC, Maastricht University, PO Box 616, 6200MD, Maastricht, The Netherlands.
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Advances in the evaluation and management of cortical/cerebral visual impairment in children. Surv Ophthalmol 2020; 65:708-724. [DOI: 10.1016/j.survophthal.2020.03.001] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 03/02/2020] [Accepted: 03/09/2020] [Indexed: 12/14/2022]
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Sysoeva OV, Smirnov K, Stroganova TA. Sensory evoked potentials in patients with Rett syndrome through the lens of animal studies: Systematic review. Clin Neurophysiol 2019; 131:213-224. [PMID: 31812082 DOI: 10.1016/j.clinph.2019.11.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 11/07/2019] [Accepted: 11/11/2019] [Indexed: 01/04/2023]
Abstract
OBJECTIVE Systematically review the abnormalities in event related potential (ERP) recorded in Rett Syndrome (RTT) patients and animals in search of translational biomarkers of deficits related to the particular neurophysiological processes of known genetic origin (MECP2 mutations). METHODS Pubmed, ISI Web of Knowledge and BIORXIV were searched for the relevant articles according to PRISMA standards. RESULTS ERP components are generally delayed across all sensory modalities both in RTT patients and its animal model, while findings on ERPs amplitude strongly depend on stimulus properties and presentation rate. Studies on RTT animal models uncovered the abnormalities in the excitatory and inhibitory transmission as critical mechanisms underlying the ERPs changes, but showed that even similar ERP alterations in auditory and visual domains have a diverse neural basis. A range of novel approaches has been developed in animal studies bringing along the meaningful neurophysiological interpretation of ERP measures in RTT patients. CONCLUSIONS While there is a clear evidence for sensory ERPs abnormalities in RTT, to further advance the field there is a need in a large-scale ERP studies with the functionally-relevant experimental paradigms. SIGNIFICANCE The review provides insights into domain-specific neural basis of the ERP abnormalities and promotes clinical application of the ERP measures as the non-invasive functional biomarkers of RTT pathophysiology.
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Affiliation(s)
- Olga V Sysoeva
- The Cognitive Neurophysiology Laboratory, Department of Pediatrics, Albert Einstein College of Medicine & Montefiore Medical Center, Bronx, New York, USA; The Cognitive Neurophysiology Laboratory, Ernest J. Del Monte Institute for Neuroscience, Department of Neuroscience, University of Rochester School of Medicine and Dentistry, Rochester, New York, USA; The Laboratory of Human Higher Nervous Activity, Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, Moscow, Russia.
| | - Kirill Smirnov
- Department of Neuroontogenesis, Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Science, Moscow, Russia.
| | - Tatiana A Stroganova
- Center for Neurocognitive Research (MEG-Center), Moscow State University of Psychology and Education (MSUPE), Moscow, Russia; Autism Research Laboratory, Moscow State University of Psychology and Education (MSUPE), Moscow, Russia.
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Smith ES, Smith DR, Eyring C, Braileanu M, Smith-Connor KS, Ei Tan Y, Fowler AY, Hoffman GE, Johnston MV, Kannan S, Blue ME. Altered trajectories of neurodevelopment and behavior in mouse models of Rett syndrome. Neurobiol Learn Mem 2019; 165:106962. [PMID: 30502397 PMCID: PMC8040058 DOI: 10.1016/j.nlm.2018.11.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Revised: 10/17/2018] [Accepted: 11/16/2018] [Indexed: 12/12/2022]
Abstract
Rett Syndrome (RTT) is a genetic disorder that is caused by mutations in the x-linked gene coding for methyl-CpG-biding-protein 2 (MECP2) and that mainly affects females. Male and female transgenic mouse models of RTT have been studied extensively, and we have learned a great deal regarding RTT neuropathology and how MeCP2 deficiency may be influencing brain function and maturation. In this manuscript we review what is known concerning structural and coinciding functional and behavioral deficits in RTT and in mouse models of MeCP2 deficiency. We also introduce our own corroborating data regarding behavioral phenotype and morphological alterations in volume of the cortex and striatum and the density of neurons, aberrations in experience-dependent plasticity within the barrel cortex and the impact of MeCP2 loss on glial structure. We conclude that regional structural changes in genetic models of RTT show great similarity to the alterations in brain structure of patients with RTT. These region-specific modifications often coincide with phenotype onset and contribute to larger issues of circuit connectivity, progression, and severity. Although the alterations seen in mouse models of RTT appear to be primarily due to cell-autonomous effects, there are also non-cell autonomous mechanisms including those caused by MeCP2-deficient glia that negatively impact healthy neuronal function. Collectively, this body of work has provided a solid foundation on which to continue to build our understanding of the role of MeCP2 on neuronal and glial structure and function, its greater impact on neural development, and potential new therapeutic avenues.
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Affiliation(s)
- Elizabeth S Smith
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Dani R Smith
- Department of Psychological and Brain Sciences, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Charlotte Eyring
- The Hugo W. Moser Research Institute at Kennedy Krieger, Inc., Baltimore, MD 21205, USA
| | - Maria Braileanu
- Undergraduate Program in Neuroscience, The Krieger School of Arts and Sciences, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Karen S Smith-Connor
- The Hugo W. Moser Research Institute at Kennedy Krieger, Inc., Baltimore, MD 21205, USA
| | - Yew Ei Tan
- Perdana University Graduate School of Medicine, Kuala Lumpur, Malaysia
| | - Amanda Y Fowler
- Department of Biology, Morgan State University, Baltimore, MD 21251, USA
| | - Gloria E Hoffman
- Department of Biology, Morgan State University, Baltimore, MD 21251, USA
| | - Michael V Johnston
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; The Hugo W. Moser Research Institute at Kennedy Krieger, Inc., Baltimore, MD 21205, USA
| | - Sujatha Kannan
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; The Hugo W. Moser Research Institute at Kennedy Krieger, Inc., Baltimore, MD 21205, USA
| | - Mary E Blue
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; The Hugo W. Moser Research Institute at Kennedy Krieger, Inc., Baltimore, MD 21205, USA.
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Abstract
Rett syndrome (RTT) is a severe neurological disorder caused by mutations in the gene encoding methyl-CpG-binding protein 2 (MeCP2). Almost two decades of research into RTT have greatly advanced our understanding of the function and regulation of the multifunctional protein MeCP2. Here, we review recent advances in understanding how loss of MeCP2 impacts different stages of brain development, discuss recent findings demonstrating the molecular role of MeCP2 as a transcriptional repressor, assess primary and secondary effects of MeCP2 loss and examine how loss of MeCP2 can result in an imbalance of neuronal excitation and inhibition at the circuit level along with dysregulation of activity-dependent mechanisms. These factors present challenges to the search for mechanism-based therapeutics for RTT and suggest specific approaches that may be more effective than others.
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Townend GS, van de Berg R, de Breet LHM, Hiemstra M, Wagter L, Smeets E, Widdershoven J, Kingma H, Curfs LMG. Oculomotor Function in Individuals With Rett Syndrome. Pediatr Neurol 2018; 88:48-58. [PMID: 30340908 DOI: 10.1016/j.pediatrneurol.2018.08.022] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 08/17/2018] [Accepted: 08/18/2018] [Indexed: 11/17/2022]
Abstract
BACKGROUND Individuals with Rett syndrome (RTT) are notoriously reliant on the use of eye gaze as a primary means of communication. Underlying an ability to communicate successfully via eye gaze is a complex matrix of requirements, with an intact oculomotor system being just one element. To date, the underlying neural and motor pathways associated with eye gaze are relatively under-researched in RTT. PURPOSE This study was undertaken to plug this gap in knowledge and to further the understanding of RTT in one specific area of development and function, namely oculomotor function. MATERIAL AND METHODS The eye movements of 18 girls and young women with RTT were assessed by electronystagmography (ENG). This tested their horizontal saccadic and smooth pursuit eye movements as well as optokinetic nystagmus and vestibulo-ocular reflex. Their results were compared with normative data collected from 16 typically developing children and teenagers. RESULTS Overall, the individuals with RTT demonstrated a range of eye movements on a par with their typically developing peers. However, there were a number of difficulties in executing the ENG testing with the RTT cohort which made quantitative analysis tricky, such as reduced motivation and attention to test materials and low-quality electrode signals. CONCLUSIONS This study suggests that individuals with RTT have an intact oculomotor system. However, modifications should be made to the ENG assessment procedure to combat problems in testing and add strength to the results. Further investigation into these testing difficulties is warranted in order to inform such modifications.
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Affiliation(s)
- Gillian S Townend
- Rett Expertise Centre Netherlands - GKC, Maastricht University Medical Center, Maastricht, The Netherlands.
| | - Raymond van de Berg
- Rett Expertise Centre Netherlands - GKC, Maastricht University Medical Center, Maastricht, The Netherlands; Division of Balance Disorders, Department of Otorhinolaryngology and Head and Neck Surgery, Maastricht University Medical Center, Maastricht, The Netherlands; Faculty of Physics, Tomsk State University, Tomsk, Russia
| | | | - Monique Hiemstra
- Faculty of Medicine, Maastricht University, Maastricht, The Netherlands
| | - Laura Wagter
- Faculty of Medicine, Maastricht University, Maastricht, The Netherlands
| | - Eric Smeets
- Rett Expertise Centre Netherlands - GKC, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Josine Widdershoven
- Division of Balance Disorders, Department of Otorhinolaryngology and Head and Neck Surgery, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Herman Kingma
- Division of Balance Disorders, Department of Otorhinolaryngology and Head and Neck Surgery, Maastricht University Medical Center, Maastricht, The Netherlands; Faculty of Physics, Tomsk State University, Tomsk, Russia
| | - Leopold M G Curfs
- Rett Expertise Centre Netherlands - GKC, Maastricht University Medical Center, Maastricht, The Netherlands
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Ahonniska-Assa J, Polack O, Saraf E, Wine J, Silberg T, Nissenkorn A, Ben-Zeev B. Assessing cognitive functioning in females with Rett syndrome by eye-tracking methodology. Eur J Paediatr Neurol 2018; 22:39-45. [PMID: 29079079 DOI: 10.1016/j.ejpn.2017.09.010] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2017] [Revised: 08/15/2017] [Accepted: 09/28/2017] [Indexed: 10/18/2022]
Abstract
BACKGROUND While many individuals with severe developmental impairments learn to communicate with augmentative and alternative communication (AAC) devices, a significant number of individuals show major difficulties in the effective use of AAC. Recent technological innovations, i.e., eye-tracking technology (ETT), aim to improve the transparency of communication and may also enable a more valid cognitive assessment. OBJECTIVES To investigate whether ETT in forced-choice tasks can enable children with very severe motor and speech impairments to respond consistently, allowing a more reliable evaluation of their language comprehension. METHODS Participants were 17 girls with Rett syndrome (M = 6:06 years). Their ability to respond by eye gaze was first practiced with computer games using ETT. Afterwards, their receptive vocabulary was assessed using the Peabody Picture Vocabulary Test-4 (PPVT-4). Target words were orally presented and participants responded by focusing their eyes on the preferred picture. RESULTS Remarkable differences between the participants in receptive vocabulary were demonstrated using ETT. The verbal comprehension abilities of 32% of the participants ranged from low-average to mild cognitive impairment, and the other 68% of the participants showed moderate to severe impairment. Young age at the time of assessment was positively correlated with higher receptive vocabulary. CONCLUSIONS The use of ETT seems to make the communicational signals of children with severe motor and communication impairments more easily understood. Early practice of ETT may improve the quality of communication and enable more reliable conclusions in learning and assessment sessions.
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Affiliation(s)
- Jaana Ahonniska-Assa
- Edmond and Lily Safra Children's Hospital, Chaim Sheba Medical Center, Ramat Gan, Israel; School of Behavioral Sciences, The Academic College of Tel Aviv Jaffo, Tel Aviv Jaffo, Israel.
| | - Orli Polack
- Edmond and Lily Safra Children's Hospital, Chaim Sheba Medical Center, Ramat Gan, Israel
| | - Einat Saraf
- Shirat Halev School, Ministry of Education, Israel; Israeli Rett Syndrome Center, Israel
| | - Judy Wine
- Israeli Rett Syndrome Center, Israel; Omer Center for Augmentative and Alternative Communication, Israel
| | - Tamar Silberg
- Edmond and Lily Safra Children's Hospital, Chaim Sheba Medical Center, Ramat Gan, Israel; Department of Psychology, Bar Ilan University, Ramat Gan, Israel
| | - Andreea Nissenkorn
- Edmond and Lily Safra Children's Hospital, Chaim Sheba Medical Center, Ramat Gan, Israel; Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Bruria Ben-Zeev
- Edmond and Lily Safra Children's Hospital, Chaim Sheba Medical Center, Ramat Gan, Israel; Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
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Clarkson T, LeBlanc J, DeGregorio G, Vogel-Farley V, Barnes K, Kaufmann WE, Nelson CA. Adapting the Mullen Scales of Early Learning for a Standardized Measure of Development in Children With Rett Syndrome. INTELLECTUAL AND DEVELOPMENTAL DISABILITIES 2017; 55:419-431. [PMID: 29194024 DOI: 10.1352/1934-9556-55.6.419] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Rett Syndrome (RTT) is characterized by severe impairment in fine motor (FM) and expressive language (EL) function, making accurate evaluations of development difficult with standardized assessm ents. In this study, the administration and scoring of the Mullen Scales of Early Learning (MSEL) were adapted to eliminate the confounding effects of FM and EL impairments in assessing development. Forty-seven girls with RTT were assessed with the Adapted-MSEL (MSEL-A), a subset (n = 30) was also assessed using the Vineland Adaptive Behavior Scales-Second Edition (Vineland-II) and a further subset (n = 17) was assessed using an eye-tracking version of the MSEL (MSEL-ET). Participants performed better on the visual reception (VR) and receptive language (RL) domains compared to the FM and EL domains on the MSEL-A. Individual performance on each domain was independent of other domains. Corresponding MSEL-A and Vineland-II domains were significantly correlated. The MSEL-ET was as accurate as the MSEL-A in assessing VR and RL, yet took a 44% less time. Results suggested that the MSEL-A and the MSEL-ET could be viable measures for accurately assessing developmental domains in children with RTT.
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Affiliation(s)
- Tessa Clarkson
- Tessa Clarkson, Jocelyn LeBlanc, Geneva DeGregorio, Vanessa Vogel-Farley, and Katherine Barnes, Boston Children's Hospital, MA; Walter E. Kaufmann, Boston Children's Hospital, MA and Harvard Medical School, Boston, MA; and Charles A. Nelson, Boston Children's Hospital, Harvard Medical School, Boston, and Harvard Graduate School of Education, Boston, MA
| | - Jocelyn LeBlanc
- Tessa Clarkson, Jocelyn LeBlanc, Geneva DeGregorio, Vanessa Vogel-Farley, and Katherine Barnes, Boston Children's Hospital, MA; Walter E. Kaufmann, Boston Children's Hospital, MA and Harvard Medical School, Boston, MA; and Charles A. Nelson, Boston Children's Hospital, Harvard Medical School, Boston, and Harvard Graduate School of Education, Boston, MA
| | - Geneva DeGregorio
- Tessa Clarkson, Jocelyn LeBlanc, Geneva DeGregorio, Vanessa Vogel-Farley, and Katherine Barnes, Boston Children's Hospital, MA; Walter E. Kaufmann, Boston Children's Hospital, MA and Harvard Medical School, Boston, MA; and Charles A. Nelson, Boston Children's Hospital, Harvard Medical School, Boston, and Harvard Graduate School of Education, Boston, MA
| | - Vanessa Vogel-Farley
- Tessa Clarkson, Jocelyn LeBlanc, Geneva DeGregorio, Vanessa Vogel-Farley, and Katherine Barnes, Boston Children's Hospital, MA; Walter E. Kaufmann, Boston Children's Hospital, MA and Harvard Medical School, Boston, MA; and Charles A. Nelson, Boston Children's Hospital, Harvard Medical School, Boston, and Harvard Graduate School of Education, Boston, MA
| | - Katherine Barnes
- Tessa Clarkson, Jocelyn LeBlanc, Geneva DeGregorio, Vanessa Vogel-Farley, and Katherine Barnes, Boston Children's Hospital, MA; Walter E. Kaufmann, Boston Children's Hospital, MA and Harvard Medical School, Boston, MA; and Charles A. Nelson, Boston Children's Hospital, Harvard Medical School, Boston, and Harvard Graduate School of Education, Boston, MA
| | - Walter E Kaufmann
- Tessa Clarkson, Jocelyn LeBlanc, Geneva DeGregorio, Vanessa Vogel-Farley, and Katherine Barnes, Boston Children's Hospital, MA; Walter E. Kaufmann, Boston Children's Hospital, MA and Harvard Medical School, Boston, MA; and Charles A. Nelson, Boston Children's Hospital, Harvard Medical School, Boston, and Harvard Graduate School of Education, Boston, MA
| | - Charles A Nelson
- Tessa Clarkson, Jocelyn LeBlanc, Geneva DeGregorio, Vanessa Vogel-Farley, and Katherine Barnes, Boston Children's Hospital, MA; Walter E. Kaufmann, Boston Children's Hospital, MA and Harvard Medical School, Boston, MA; and Charles A. Nelson, Boston Children's Hospital, Harvard Medical School, Boston, and Harvard Graduate School of Education, Boston, MA
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Abstract
Autism is a complex neurodevelopmental condition, and little is known about its neurobiology. Much of autism research has focused on the social, communication and cognitive difficulties associated with the condition. However, the recent revision of the diagnostic criteria for autism has brought another key domain of autistic experience into focus: sensory processing. Here, we review the properties of sensory processing in autism and discuss recent computational and neurobiological insights arising from attention to these behaviours. We argue that sensory traits have important implications for the development of animal and computational models of the condition. Finally, we consider how difficulties in sensory processing may relate to the other domains of behaviour that characterize autism.
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15
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Boivin MJ, Weiss J, Chhaya R, Seffren V, Awadu J, Sikorskii A, Giordani B. The feasibility of automated eye tracking with the Early Childhood Vigilance Test of attention in younger HIV-exposed Ugandan children. Neuropsychology 2017; 31:525-534. [PMID: 28541084 PMCID: PMC5501490 DOI: 10.1037/neu0000382] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
OBJECTIVE Tobii eye tracking was compared with webcam-based observer scoring on an animation viewing measure of attention (Early Childhood Vigilance Test; ECVT) to evaluate the feasibility of automating measurement and scoring. Outcomes from both scoring approaches were compared with the Mullen Scales of Early Learning (MSEL), Color-Object Association Test (COAT), and Behavior Rating Inventory of Executive Function for preschool children (BRIEF-P). METHOD A total of 44 children 44 to 65 months of age were evaluated with the ECVT, COAT, MSEL, and BRIEF-P. Tobii ×2-30 portable infrared cameras were programmed to monitor pupil direction during the ECVT 6-min animation and compared with observer-based PROCODER webcam scoring. RESULTS Children watched 78% of the cartoon (Tobii) compared with 67% (webcam scoring), although the 2 measures were highly correlated (r = .90, p = .001). It is possible for 2 such measures to be highly correlated even if one is consistently higher than the other (Bergemann et al., 2012). Both ECVT Tobii and webcam ECVT measures significantly correlated with COAT immediate recall (r = .37, p = .02 vs. r = .38, p = .01, respectively) and total recall (r = .33, p = .06 vs. r = .42, p = .005) measures. However, neither the Tobii eye tracking nor PROCODER webcam ECVT measures of attention correlated with MSEL composite cognitive performance or BRIEF-P global executive composite. CONCLUSION ECVT scoring using Tobii eye tracking is feasible with at-risk very young African children and consistent with webcam-based scoring approaches in their correspondence to one another and other neurocognitive performance-based measures. By automating measurement and scoring, eye tracking technologies can improve the efficiency and help better standardize ECVT testing of attention in younger children. This holds promise for other neurodevelopmental tests where eye movements, tracking, and gaze length can provide important behavioral markers of neuropsychological and neurodevelopmental processes associated with such tests. (PsycINFO Database Record
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Affiliation(s)
- Michael J. Boivin
- Michigan State University Department of Psychiatry and of Neurology & Ophthalmology, University of Michigan Department of Psychiatry
| | | | - Ronak Chhaya
- Michigan State University College of Human Medicine
| | | | - Jorem Awadu
- Michigan State University College of Education
| | - Alla Sikorskii
- Michigan State University Department of Statistics and Probability
| | - Bruno Giordani
- University of Michigan Department of Psychiatry, Psychology, and Nursing
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16
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Chhaya R, Weiss J, Seffren V, Sikorskii A, Winke PM, Ojuka JC, Boivin MJ. The feasibility of an automated eye-tracking-modified Fagan test of memory for human faces in younger Ugandan HIV-exposed children. Child Neuropsychol 2017; 24:686-701. [PMID: 28532283 DOI: 10.1080/09297049.2017.1329412] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
OBJECTIVE The Fagan Test of Infant Intelligence (FTII) uses longer gaze length for unfamiliar versus familiar human faces to gauge visual-spatial encoding, attention, and working memory in infants. Our objective was to establish the feasibility of automated eye tracking with the FTII in HIV-exposed Ugandan infants. METHOD The FTII was administered to 31 perinatally HIV-exposed noninfected (HEU) Ugandan children 6-12 months of age (11 boys; M = 0.69 years, SD = 0.14; 19 girls; M = 0.79, SD = 0.15). A series of 10 different faces were presented (familiar face exposure for 25 s followed by a gaze preference trial of 15 s with both the familiar and unfamiliar faces). Tobii X2-30 infrared camera for pupil detection provided automated eye-tracking measures of gaze location and length during presentation of Ugandan faces selected to correspond to the gender, age (adult, child), face expression, and orientation of the original FTII. Eye-tracking gaze length for unfamiliar faces was correlated with performance on the Mullen Scales of Early Learning (MSEL). RESULTS Infants gazed longer at the novel picture compared to familiar across 10 novelty preference trials. Better MSEL cognitive development was correlated with proportionately longer time spent looking at the novel faces (r(30) = 0.52, p = .004); especially for the Fine Motor Cognitive Sub-scale (r(30) = 0.54, p = .002). CONCLUSION Automated eye tracking in a human face recognition test proved feasible and corresponded to the MSEL composite cognitive development in HEU infants in a resource-constrained clinical setting. Eye tracking may be a viable means of enhancing the validity and accuracy of other neurodevelopmental measures in at-risk children in sub-Saharan Africa.
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Affiliation(s)
- Ronak Chhaya
- a College of Human Medicine , Michigan State University , East Lansing , MI , USA
| | - Jonathan Weiss
- a College of Human Medicine , Michigan State University , East Lansing , MI , USA
| | - Victoria Seffren
- b School of Public Health , University of Michigan , Ann Arbor , MI , USA
| | - Alla Sikorskii
- c Department of Statistics & Probability , Michigan State University , East Lansing , MI , USA
| | - Paula M Winke
- d Department of Linguistics, Germanic, Slavic, Asian, & African Languages , Michigan State University , East Lansing , MI , USA
| | | | - Michael J Boivin
- f Department of Psychiatry and Neurology & Ophthalmology , Michigan State University , East Lansing , MI , USA
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17
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Jointly reduced inhibition and excitation underlies circuit-wide changes in cortical processing in Rett syndrome. Proc Natl Acad Sci U S A 2016; 113:E7287-E7296. [PMID: 27803317 DOI: 10.1073/pnas.1615330113] [Citation(s) in RCA: 113] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Rett syndrome (RTT) arises from loss-of-function mutations in methyl-CpG binding protein 2 gene (Mecp2), but fundamental aspects of its physiological mechanisms are unresolved. Here, by whole-cell recording of synaptic responses in MeCP2 mutant mice in vivo, we show that visually driven excitatory and inhibitory conductances are both reduced in cortical pyramidal neurons. The excitation-to-inhibition (E/I) ratio is increased in amplitude and prolonged in time course. These changes predict circuit-wide reductions in response reliability and selectivity of pyramidal neurons to visual stimuli, as confirmed by two-photon imaging. Targeted recordings reveal that parvalbumin-expressing (PV+) interneurons in mutant mice have reduced responses. PV-specific MeCP2 deletion alone recapitulates effects of global MeCP2 deletion on cortical circuits, including reduced pyramidal neuron responses and reduced response reliability and selectivity. Furthermore, MeCP2 mutant mice show reduced expression of the cation-chloride cotransporter KCC2 (K+/Cl- exporter) and a reduced KCC2/NKCC1 (Na+/K+/Cl- importer) ratio. Perforated patch recordings demonstrate that the reversal potential for GABA is more depolarized in mutant mice, but is restored by application of the NKCC1 inhibitor bumetanide. Treatment with recombinant human insulin-like growth factor-1 restores responses of PV+ and pyramidal neurons and increases KCC2 expression to normalize the KCC2/NKCC1 ratio. Thus, loss of MeCP2 in the brain alters both excitation and inhibition in brain circuits via multiple mechanisms. Loss of MeCP2 from a specific interneuron subtype contributes crucially to the cell-specific and circuit-wide deficits of RTT. The joint restoration of inhibition and excitation in cortical circuits is pivotal for functionally correcting the disorder.
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18
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Foxe JJ, Burke KM, Andrade GN, Djukic A, Frey HP, Molholm S. Automatic cortical representation of auditory pitch changes in Rett syndrome. J Neurodev Disord 2016; 8:34. [PMID: 27594924 PMCID: PMC5009506 DOI: 10.1186/s11689-016-9166-5] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 08/10/2016] [Indexed: 12/11/2022] Open
Abstract
Background Over the typical course of Rett syndrome, initial language and communication abilities deteriorate dramatically between the ages of 1 and 4 years, and a majority of these children go on to lose all oral communication abilities. It becomes extremely difficult for clinicians and caretakers to accurately assess the level of preserved auditory functioning in these children, an issue of obvious clinical import. Non-invasive electrophysiological techniques allow for the interrogation of auditory cortical processing without the need for overt behavioral responses. In particular, the mismatch negativity (MMN) component of the auditory evoked potential (AEP) provides an excellent and robust dependent measure of change detection and auditory sensory memory. Here, we asked whether females with Rett syndrome would produce the MMN to occasional changes in pitch in a regularly occurring stream of auditory tones. Methods Fourteen girls with genetically confirmed Rett syndrome and 22 age-matched neurotypical controls participated (ages 3.9–21.1 years). High-density electrophysiological recordings from 64 scalp electrodes were made while participants passively listened to a regularly occurring stream of 503-Hz auditory tone pips that was occasionally (15 % of presentations) interrupted by a higher-pitched deviant tone of 996 Hz. The MMN was derived by subtracting the AEP to these deviants from the AEP produced to the standard. Results Despite clearly anomalous morphology and latency of the AEP to simple pure-tone inputs in Rett syndrome, the MMN response was evident in both neurotypicals and Rett patients. However, we found that the pitch-evoked MMN was both delayed and protracted in duration in Rett, pointing to slowing of auditory responsiveness. Conclusions The presence of the MMN in Rett patients suggests preserved abilities to process pitch changes in auditory sensory memory. This work represents a beginning step in an effort to comprehensively map the extent of auditory cortical functioning in Rett syndrome. These easily obtained objective brain measures of auditory processing have promise as biomarkers against which future therapeutic efforts can be assayed.
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Affiliation(s)
- John J Foxe
- Department of Neuroscience, The Del Monte Institute for Neuroscience, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642 USA ; Department of Pediatrics, The Sheryl and Daniel R. Tishman Cognitive Neurophysiology Laboratory, Albert Einstein College of Medicine & Montefiore Medical Center, Bronx, NY 10461 USA ; The Dominic P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461 USA
| | - Kelly M Burke
- Department of Pediatrics, The Sheryl and Daniel R. Tishman Cognitive Neurophysiology Laboratory, Albert Einstein College of Medicine & Montefiore Medical Center, Bronx, NY 10461 USA ; The Dominic P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461 USA
| | - Gizely N Andrade
- Department of Pediatrics, The Sheryl and Daniel R. Tishman Cognitive Neurophysiology Laboratory, Albert Einstein College of Medicine & Montefiore Medical Center, Bronx, NY 10461 USA
| | - Aleksandra Djukic
- Department of Neurology, Rett Syndrome Center, Montefiore Medical Center & Albert Einstein College of Medicine, Bronx, NY 10467 USA
| | - Hans-Peter Frey
- Department of Pediatrics, The Sheryl and Daniel R. Tishman Cognitive Neurophysiology Laboratory, Albert Einstein College of Medicine & Montefiore Medical Center, Bronx, NY 10461 USA ; Department of Neurology, Columbia University Medical Center, New York, NY 10032 USA
| | - Sophie Molholm
- Department of Pediatrics, The Sheryl and Daniel R. Tishman Cognitive Neurophysiology Laboratory, Albert Einstein College of Medicine & Montefiore Medical Center, Bronx, NY 10461 USA ; The Dominic P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461 USA
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19
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Sandberg AD, Ehlers S, Hagberg B, Gillberg C. The Rett Syndrome Complex. AUTISM : THE INTERNATIONAL JOURNAL OF RESEARCH AND PRACTICE 2016. [DOI: 10.1177/1362361300004003003] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Communicative functions and their relationship with overall developmental level and autistic features were studied in eight young women with disorders in the Rett syndrome complex, three with the classical variant and five with variants with partially preserved/regained speech. The Vineland Adaptive Behaviour Scales, individual structured observation, and a specially designed structured interview covering early pre-linguistic and linguistic development, current receptive and expressive language and non-verbal communication skills, were used. Autistic features were evaluated in accordance with the DSM-IV. Low levels of communicative abilities and overall functioning were demonstrated. In most cases, the communicative abilities did not reach the level expected on the basis of overall development. Joint attention behaviours and expressions of communicative intent were rare. However, six of the eight subjects showed clear examples of social interaction abilities.‘Eye pointing’, as distinct from ‘eye communication’, was demonstrated only in a minority of the cases. The level of communicative function at developmental arrest did not predict later language ability. It is suggested that intervention should focus on developing further the joint attention behaviours, intentional communications and communicative functions spontaneously used by individuals with disorders in the Rett syndrome complex.
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20
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LeBlanc JJ, DeGregorio G, Centofante E, Vogel-Farley VK, Barnes K, Kaufmann WE, Fagiolini M, Nelson CA. Visual evoked potentials detect cortical processing deficits in Rett syndrome. Ann Neurol 2015; 78:775-86. [PMID: 26332183 DOI: 10.1002/ana.24513] [Citation(s) in RCA: 85] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Revised: 08/07/2015] [Accepted: 08/26/2015] [Indexed: 01/26/2023]
Abstract
OBJECTIVE Rett syndrome (RTT) is a neurodevelopmental disorder caused by mutation of the X-linked MECP2 gene and characterized by developmental regression during the first few years of life. The objective of this study was to investigate if the visual evoked potential (VEP) could be used as an unbiased, quantitative biomarker to monitor brain function in RTT. METHODS We recorded pattern-reversal VEPs in Mecp2 heterozygous female mice and 34 girls with RTT. The amplitudes and latencies of VEP waveform components were quantified, and were related to disease stage, clinical severity, and MECP2 mutation type in patients. Visual acuity was also assessed in both mice and patients by modulating the spatial frequency of the stimuli. RESULTS Mecp2 heterozygous female mice and RTT patients exhibited a similar decrease in VEP amplitude that was most striking in the later stages of the disorder. RTT patients also displayed a slower recovery from the principal peak of the VEP response that was impacted by MECP2 mutation type. When the spatial frequency of the stimulus was increased, both patients and mice displayed a deficit in discriminating smaller patterns, indicating lower visual spatial acuity in RTT. INTERPRETATION VEP is a method that can be used to assess brain function across species and in children with severe disabilities like RTT. Our findings support the introduction of standardized VEP analysis in clinical and research settings to probe the neurobiological mechanism underlying functional impairment and to longitudinally monitor progression of the disorder and response to treatment.
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Affiliation(s)
- Jocelyn J LeBlanc
- Laboratories of Cognitive Neuroscience, Division of Developmental Medicine, Boston Children's Hospital, Boston.,F. M. Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital, Boston.,Harvard Medical School, Boston
| | - Geneva DeGregorio
- Laboratories of Cognitive Neuroscience, Division of Developmental Medicine, Boston Children's Hospital, Boston
| | - Eleonora Centofante
- F. M. Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital, Boston
| | - Vanessa K Vogel-Farley
- Laboratories of Cognitive Neuroscience, Division of Developmental Medicine, Boston Children's Hospital, Boston
| | - Katherine Barnes
- Rett Syndrome Program, Department of Neurology, Boston Children's Hospital, Boston
| | - Walter E Kaufmann
- Harvard Medical School, Boston.,Rett Syndrome Program, Department of Neurology, Boston Children's Hospital, Boston
| | - Michela Fagiolini
- F. M. Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital, Boston.,Harvard Medical School, Boston
| | - Charles A Nelson
- Laboratories of Cognitive Neuroscience, Division of Developmental Medicine, Boston Children's Hospital, Boston.,Harvard Medical School, Boston.,Harvard Graduate School of Education, Cambridge, MA
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Djukic A, Rose SA, Jankowski JJ, Feldman JF. Rett syndrome: recognition of facial expression and its relation to scanning patterns. Pediatr Neurol 2014; 51:650-6. [PMID: 25217338 DOI: 10.1016/j.pediatrneurol.2014.07.022] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2014] [Revised: 07/16/2014] [Accepted: 07/17/2014] [Indexed: 01/21/2023]
Abstract
BACKGROUND Rett syndrome is a severely disabling neurodevelopmental disorder caused by mutations in the X-linked MECP2 gene. Very little is known about its cognitive phenotype and nothing about recognition of emotional expression, a key factor for social interaction and communication. Using eye tracking technology, a technique uniquely suited for studying cognition in this disorder, we examined this ability here. METHODS Rett syndrome female patients (n = 37; 2-31 years) and a typically developing age- and gender-matched comparison group (n =34; 2-30 years) were assessed on recognition of three basic emotions (happy, sad, and fear) using six visual paired-comparison problems. Each problem consisted of a 10-second familiarization, in which two identical faces posing one emotion were presented, followed by a 10-second test, in which the familiar emotion was paired with a novel one posed by the same model. Recognition was inferred from preferential looking to the novel target on test. During familiarization, attention was measured by total looking time, number and/or length of fixations, and gaze dispersion across three key facial features (eyes, nose, and mouth). RESULTS Individuals with Rett syndrome had difficulty recognizing most emotional expressions, unlike the typically developing comparison group. Also, their scanpaths were atypical-less looking, fewer and/or longer fixations, and less time devoted to all facial features (48% versus 72%), particularly the mouth. Significant correlations between looking to critical features and recognition underscored the importance of scanning. CONCLUSIONS Our results suggest that individuals with Rett syndrome have difficulty reading emotional expressions and that these problems are linked to atypicalities in scanning.
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Affiliation(s)
- Aleksandra Djukic
- Rett Syndrome Center, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York
| | - Susan A Rose
- Department of Pediatrics, Children's Hospital at Montefiore, Albert Einstein College of Medicine, Bronx, New York.
| | - Jeffery J Jankowski
- Department of Pediatrics, Children's Hospital at Montefiore, Albert Einstein College of Medicine, Bronx, New York; Department of Social Sciences, Queensborough Community College, City University of New York, New York
| | - Judith F Feldman
- Department of Pediatrics, Children's Hospital at Montefiore, Albert Einstein College of Medicine, Bronx, New York
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22
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Bosch DGM, Boonstra FN, Willemsen MAAP, Cremers FPM, de Vries BBA. Low vision due to cerebral visual impairment: differentiating between acquired and genetic causes. BMC Ophthalmol 2014; 14:59. [PMID: 24886270 PMCID: PMC4021540 DOI: 10.1186/1471-2415-14-59] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2013] [Accepted: 04/28/2014] [Indexed: 11/21/2022] Open
Abstract
Background To gain more insight into genetic causes of cerebral visual impairment (CVI) in children and to compare ophthalmological findings between genetic and acquired forms of CVI. Methods The clinical data of 309 individuals (mainly children) with CVI, and a visual acuity ≤0.3 were analyzed for etiology and ocular variables. A differentiation was made between acquired and genetic causes. However, in persons with West syndrome or hydrocephalus, it might be impossible to unravel whether CVI is caused by the seizure disorder or increased intracranial pressure or by the underlying disorder (that in itself can be acquired or genetic). In two subgroups, individuals with ‘purely’ acquired CVI and with ‘purely’ genetic CVI, the ocular variables (such as strabismus, pale optic disc and visual field defects) were compared. Results It was possible to identify a putative cause for CVI in 60% (184/309) of the cohort. In the remaining 40% the etiology could not be determined. A ‘purely’ acquired cause was identified in 80 of the patients (26%). West syndrome and/or hydrocephalus was identified in 21 patients (7%), and in 17 patients (6%) both an acquired cause and West and/or hydrocephalus was present. In 66 patients (21%) a genetic diagnosis was obtained, of which 38 (12%) had other possible risk factor (acquired, preterm birth, West syndrome or hydrocephalus), making differentiation between acquired and genetic not possible. In the remaining 28 patients (9%) a ‘purely’ genetic cause was identified. CVI was identified for the first time in several genetic syndromes, such as ATR-X, Mowat-Wilson, and Pitt Hopkins syndrome. In the subgroup with ‘purely’ acquired causes (N = 80) strabismus (88% versus 64%), pale optic discs (65% versus 27%) and visual field defects (72% versus 30%) could be observed more frequent than in the subgroup with ‘purely’ genetic disorders (N = 28). Conclusions We conclude that CVI can be part of a genetic syndrome and that abnormal ocular findings are present more frequently in acquired forms of CVI.
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Affiliation(s)
| | | | | | | | - Bert B A de Vries
- Department of Human Genetics, Radboud University Medical Center, P,O, Box 9101, Nijmegen, HB 6500, The Netherlands.
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Fabio RA, Castelli I, Marchetti A, Antonietti A. Training communication abilities in Rett Syndrome through reading and writing. Front Psychol 2013; 4:911. [PMID: 24367345 PMCID: PMC3854542 DOI: 10.3389/fpsyg.2013.00911] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2013] [Accepted: 11/16/2013] [Indexed: 01/28/2023] Open
Abstract
The goal of this clinical case study is to investigate the possibility of training communication abilities in people with Rett Syndrome (RS). Usually, girls with RS never exceed the sensorimotor stage of development, but the inter-individual variability typical of RS may lead us to doubt the irrevocability of that developmental limit, especially for those girls who are engaged in cognitive rehabilitation. The case study reported here concerns a 21-year-old girl with RS who was engaged in cognitive rehabilitation training based upon the principles of Feuerstein's modificability and mediated learning theory. The training aimed to teach her basic concepts and enhance reading-writing abilities. Statistical analyses showed that the girl reached adequate reading-writing abilities, proving the validity of the cognitive intervention which allowed her to communicate by composing words with her forefinger on an alphabetic table. Although these results need to be cautiously considered as they derive from a single case study, they have implications for future cognitive rehabilitation for deeply impaired clinical conditions as in the case of RS.
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Affiliation(s)
- Rosa Angela Fabio
- Department of Cognitive Science and Education, University of Messina Messina, Italy
| | - Ilaria Castelli
- Research Unit on Theory of Mind, Department of Psychology, Catholic University of the Sacred Heart Milan, Italy
| | - Antonella Marchetti
- Research Unit on Theory of Mind, Department of Psychology, Catholic University of the Sacred Heart Milan, Italy
| | - Alessandro Antonietti
- Service of Learning and Education Psychology, Department of Psychology, Catholic University of the Sacred Heart Milan, Italy
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Rose SA, Djukic A, Jankowski JJ, Feldman JF, Fishman I, Valicenti-McDermott M. Rett syndrome: an eye-tracking study of attention and recognition memory. Dev Med Child Neurol 2013; 55:364-71. [PMID: 23488948 DOI: 10.1111/dmcn.12085] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/17/2012] [Indexed: 12/27/2022]
Abstract
AIM The aim of this study was to examine attention and recognition memory for faces and patterns in Rett syndrome, a severely disabling neurodevelopmental disorder caused by mutations in the X-linked MECP2 gene. METHOD Because Rett syndrome impairs speech and hand use, precluding most neuropsychological testing, the visual paired-comparison paradigm (VPC) was used, together with eye tracking. In the VPC, two identical stimuli are presented for familiarization. On test, the familiar stimulus and a new one are paired, and recognition inferred from preferential looking to the novel target. Attention is measured by looking time, gaze dispersion, and number/length of fixations. Twenty-seven female patients with Rett syndrome (mean age 10y 6mo; SD 6y 8mo, age range 2-22y) from the Rett clinic at a children's hospital were assessed in this study, along with 30 age- and sex-matched typically developing participants (outpatients from the same hospital). RESULTS Although patients with Rett syndrome showed recognition of both faces and patterns, with novelty scores greater than chance (50%), their performance was significantly poorer than that of the typically developing comparison group. Their attention to both was less mature and marked by a more narrowly focused gaze, with fewer and longer fixations. When inspecting faces, attention to the eyes was similar in both groups; however, patients with Rett syndrome tended to ignore the nose and mouth. INTERPRETATION This is one of the first studies to characterize attention and memory in individuals with Rett syndrome. Visually based techniques, such as the VPC, open a new avenue for quantifying the cognitive phenotype associated with this syndrome.
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Affiliation(s)
- Susan A Rose
- Department of Pediatrics, Kennedy Center, Albert Einstein College of Medicine/Children's Hospital at Montefiore, Bronx, NY 10461, USA.
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25
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Byiers B, Symons F. The need for unbiased cognitive assessment in Rett syndrome: is eye tracking the answer? Dev Med Child Neurol 2013; 55:301-2. [PMID: 23488946 PMCID: PMC4331338 DOI: 10.1111/dmcn.12088] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Breanne Byiers
- University of Minnesota; Department of Educational Psychology; Minneapolis; MN; USA
| | - Frank Symons
- University of Minnesota; Department of Educational Psychology; Minneapolis; MN; USA
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Durand S, Patrizi A, Quast KB, Hachigian L, Pavlyuk R, Saxena A, Carninci P, Hensch TK, Fagiolini M. NMDA receptor regulation prevents regression of visual cortical function in the absence of Mecp2. Neuron 2013; 76:1078-90. [PMID: 23259945 DOI: 10.1016/j.neuron.2012.12.004] [Citation(s) in RCA: 115] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/03/2012] [Indexed: 10/27/2022]
Abstract
Brain function is shaped by postnatal experience and vulnerable to disruption of Methyl-CpG-binding protein, Mecp2, in multiple neurodevelopmental disorders. How Mecp2 contributes to the experience-dependent refinement of specific cortical circuits and their impairment remains unknown. We analyzed vision in gene-targeted mice and observed an initial normal development in the absence of Mecp2. Visual acuity then rapidly regressed after postnatal day P35-40 and cortical circuits largely fell silent by P55-60. Enhanced inhibitory gating and an excess of parvalbumin-positive, perisomatic input preceded the loss of vision. Both cortical function and inhibitory hyperconnectivity were strikingly rescued independent of Mecp2 by early sensory deprivation or genetic deletion of the excitatory NMDA receptor subunit, NR2A. Thus, vision is a sensitive biomarker of progressive cortical dysfunction and may guide novel, circuit-based therapies for Mecp2 deficiency.
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Affiliation(s)
- Severine Durand
- FM Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA
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Marschik PB, Kaufmann WE, Einspieler C, Bartl-Pokorny KD, Wolin T, Pini G, Budimirovic DB, Zappella M, Sigafoos J. Profiling early socio-communicative development in five young girls with the preserved speech variant of Rett syndrome. RESEARCH IN DEVELOPMENTAL DISABILITIES 2012; 33:1749-56. [PMID: 22699249 PMCID: PMC3445809 DOI: 10.1016/j.ridd.2012.04.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2012] [Accepted: 04/18/2012] [Indexed: 05/12/2023]
Abstract
Rett syndrome (RTT) is a developmental disorder characterized by regression of purposeful hand skills and spoken language, although some affected children retain some ability to speech. We assessed the communicative abilities of five young girls, who were later diagnosed with the preserved speech variant of RTT, during the pre-regression period (aged 12-24 months). Videotapes, obtained by parents during routine family situations and celebrations, were analyzed to identify communicative forms and functions used by these toddlers. Non-verbal communicative forms dominated over verbal-communicative forms for six of the eight identified communication functions. Although the girls used various non-verbal forms to make requests, for example, none of the individuals were observed to make choices or request information. Early peculiarities in the speech-language domain during the first year of life became more prominent and evident during the second year of life as general differences between typical development and atypical development become more obvious in RTT. These findings highlight the importance of assessing socio-communicative forms and functions at early age in children with RTT. The results suggest that speech-language functions did not appear to play a major role in the children's communicative attempts. We conclude that, even among children with the preserved speech variant, socio-communicative deficits are present before regression and persist after this period.
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Affiliation(s)
- Peter B. Marschik
- Institute of Physiology (Developmental Physiology and Developmental Neuroscience; IN:spired), Center for Physiological Medicine, Medical University of Graz, Austria
- Center for Genetic Disorders of Cognition and Behavior, Fragile X Clinic, Kennedy Krieger Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Walter E. Kaufmann
- Children's Hospital Boston, Harvard Medical School, Boston, MA, USA
- Center for Genetic Disorders of Cognition and Behavior, Fragile X Clinic, Kennedy Krieger Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Christa Einspieler
- Institute of Physiology (Developmental Physiology and Developmental Neuroscience; IN:spired), Center for Physiological Medicine, Medical University of Graz, Austria
- Corresponding author at: Institute of Physiology, Center for Physiological Medicine, Medical University of Graz, Harrachgasse 21/5, 8010 Graz, Austria. Tel.: +43 316 380 4266; fax: +43 316 380 9630.
| | - Katrin D. Bartl-Pokorny
- Institute of Physiology (Developmental Physiology and Developmental Neuroscience; IN:spired), Center for Physiological Medicine, Medical University of Graz, Austria
| | - Thomas Wolin
- Institute of Physiology (Developmental Physiology and Developmental Neuroscience; IN:spired), Center for Physiological Medicine, Medical University of Graz, Austria
| | - Giorgio Pini
- Tuscany Rett Centre Versilia Hospital, Lido di Camaiore, Italy
| | - Dejan B. Budimirovic
- Center for Genetic Disorders of Cognition and Behavior, Fragile X Clinic, Kennedy Krieger Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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Djukic A, Valicenti McDermott M, Mavrommatis K, Martins CL. Rett syndrome: basic features of visual processing-a pilot study of eye-tracking. Pediatr Neurol 2012; 47:25-9. [PMID: 22704012 DOI: 10.1016/j.pediatrneurol.2012.04.009] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2012] [Accepted: 04/11/2012] [Indexed: 11/15/2022]
Abstract
Consistently observed "strong eye gaze" has not been validated as a means of communication in girls with Rett syndrome, ubiquitously affected by apraxia, unable to reply either verbally or manually to questions during formal psychologic assessment. We examined nonverbal cognitive abilities and basic features of visual processing (visual discrimination attention/memory) by analyzing patterns of visual fixation in 44 girls with Rett syndrome, compared with typical control subjects. To determine features of visual fixation patterns, multiple pictures (with the location of the salient and presence/absence of novel stimuli as variables) were presented on the screen of a TS120 eye-tracker. Of the 44, 35 (80%) calibrated and exhibited meaningful patterns of visual fixation. They looked longer at salient stimuli (cartoon, 2.8 ± 2 seconds S.D., vs shape, 0.9 ± 1.2 seconds S.D.; P = 0.02), regardless of their position on the screen. They recognized novel stimuli, decreasing the fixation time on the central image when another image appeared on the periphery of the slide (2.7 ± 1 seconds S.D. vs 1.8 ± 1 seconds S.D., P = 0.002). Eye-tracking provides a feasible method for cognitive assessment and new insights into the "hidden" abilities of individuals with Rett syndrome.
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Affiliation(s)
- Aleksandra Djukic
- Rett Syndrome Center, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York, NY 10467, USA.
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29
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Eyes on DNA methylation: current evidence for DNA methylation in ocular development and disease. J Ocul Biol Dis Infor 2012; 4:95-103. [PMID: 23538551 DOI: 10.1007/s12177-012-9078-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2011] [Accepted: 03/05/2012] [Indexed: 12/20/2022] Open
Abstract
Epigenetic modulation of chromatin states constitutes a vital component of the cellular repertoire of transcriptional regulatory mechanisms. The development of new technologies capable of generating genome-wide maps of chromatin modifications has re-energized the field. We are now poised to determine how species- and tissue-specific patterns of DNA methylation, in concert with other chromatin modifications, function to establish and maintain cell- and tissue-specific patterns of gene expression during normal development, cellular differentiation, and disease. This review addresses our current understanding of the major mechanisms and function of DNA methylation in vertebrates with a historical perspective and an emphasis on what is known about DNA methylation in eye development and disease.
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Experience-dependent retinogeniculate synapse remodeling is abnormal in MeCP2-deficient mice. Neuron 2011; 70:35-42. [PMID: 21482354 DOI: 10.1016/j.neuron.2011.03.001] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/09/2011] [Indexed: 01/17/2023]
Abstract
Mutations in MECP2 underlie the neurodevelopmental disorder Rett syndrome (RTT). One hallmark of RTT is relatively normal development followed by a later onset of symptoms. Growing evidence suggests an etiology of disrupted synaptic function, yet it is unclear how these abnormalities explain the clinical presentation of RTT. Here we investigate synapse maturation in Mecp2-deficient mice at a circuit with distinct developmental phases: the retinogeniculate synapse. We find that synapse development in mutants is comparable to that of wild-type littermates between postnatal days 9 and 21, indicating that initial phases of synapse formation, elimination, and strengthening are not significantly affected by MeCP2 absence. However, during the subsequent experience-dependent phase of synapse remodeling, the circuit becomes abnormal in mutants as retinal innervation of relay neurons increases and retinal inputs fail to strengthen further. Moreover, synaptic plasticity in response to visual deprivation is disrupted in mutants. These results suggest a crucial role for Mecp2 in experience-dependent refinement of synaptic circuits.
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Calfa G, Hablitz JJ, Pozzo-Miller L. Network hyperexcitability in hippocampal slices from Mecp2 mutant mice revealed by voltage-sensitive dye imaging. J Neurophysiol 2011; 105:1768-84. [PMID: 21307327 PMCID: PMC3075283 DOI: 10.1152/jn.00800.2010] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2010] [Accepted: 02/03/2011] [Indexed: 11/22/2022] Open
Abstract
Dysfunctions of neuronal and network excitability have emerged as common features in disorders associated with intellectual disabilities, autism, and seizure activity, all common clinical manifestations of Rett syndrome (RTT), a neurodevelopmental disorder caused by loss-of-function mutations in the transcriptional regulator methyl-CpG-binding protein 2 (MeCP2). Here, we evaluated the consequences of Mecp2 mutation on hippocampal network excitability, as well as synapse structure and function using a combination of imaging and electrophysiological approaches in acute slices. Imaging the amplitude and spatiotemporal spread of neuronal depolarizations with voltage-sensitive dyes (VSD) revealed that the CA1 and CA3 regions of hippocampal slices from symptomatic male Mecp2 mutant mice are highly hyperexcitable. However, only the density of docked synaptic vesicles and the rate of release from the readily releasable pool are impaired in Mecp2 mutant mice, while synapse density and morphology are unaffected. The differences in network excitability were not observed in surgically isolated CA1 minislices, and blockade of GABAergic inhibition enhanced VSD signals to the same extent in Mecp2 mutant and wild-type mice, suggesting that network excitability originates in area CA3. Indeed, extracellular multiunit recordings revealed a higher level of spontaneous firing of CA3 pyramidal neurons in slices from symptomatic Mecp2 mutant mice. The neuromodulator adenosine reduced the amplitude and spatiotemporal spread of VSD signals evoked in CA1 of Mecp2 mutant slices to wild-type levels, suggesting its potential use as an anticonvulsant in RTT individuals. The present results suggest that hyperactive CA3 pyramidal neurons contribute to hippocampal dysfunction and possibly to limbic seizures observed in Mecp2 mutant mice and RTT individuals.
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Affiliation(s)
- Gaston Calfa
- Department of Neurobiology, Civitan International Research Center, The University of Alabama at Birmingham, Birmingham, AL 35294-2182, USA
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Newsam H, Walley RM, McKie K. Sensory Impairment in Adults With Intellectual Disabilities-An Exploration of the Awareness and Practices of Social Care Providers. JOURNAL OF POLICY AND PRACTICE IN INTELLECTUAL DISABILITIES 2010. [DOI: 10.1111/j.1741-1130.2010.00267.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Marco EJ, Skuse DH. Autism-lessons from the X chromosome. Soc Cogn Affect Neurosci 2010; 1:183-93. [PMID: 18985105 DOI: 10.1093/scan/nsl028] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2006] [Accepted: 09/18/2006] [Indexed: 02/06/2023] Open
Abstract
Recognized cases of autism spectrum disorders are on the rise. It is unclear whether this increase is attributable to secular trends in biological susceptibility, or to a change in diagnostic practices and recognition. One hint concerning etiological influences is the universally reported male excess (in the range of 4:1 to 10:1). Evidence suggests that genetic influences from the X chromosome play a crucial role in engendering this male vulnerability. In this review, we discuss three categories of genetic disease that highlight the importance of X-linked genes in the manifestation of an autistic phenotype: aneuploides (Turner syndrome and Klinefelter syndrome), trinucleotide expansions (Fragile X syndrome) and nucleotide mutations (Rett Syndrome, Neuroligins 3 & 4, and SLC6A8). The lessons from these diseases include an understanding of autistic features as a broad phenotype rather than as a single clinical entity, the role of multiple genes either alone or in concert with the manifestation of autistic features, and the role of epigenetic factors such as imprinting and X-inactivation in the expression of disease severity. Better understanding of the clinical phenotypes of social cognition and the molecular neurogenetics of X-linked gene disorders will certainly provide additional tools for understanding autism in the years to come.
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Affiliation(s)
- Elysa J Marco
- Behavioral and Brain Sciences Unit, Institute of Child Health, London, UK
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34
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Velloso RDL, Araújo CAD, Schwartzman JS. Concepts of color, shape, size and position in ten children with Rett syndrome. ARQUIVOS DE NEURO-PSIQUIATRIA 2009; 67:50-4. [DOI: 10.1590/s0004-282x2009000100013] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2008] [Accepted: 11/08/2008] [Indexed: 11/22/2022]
Abstract
Individuals with Rett syndrome (RS) present severe motor, language and cognitive deficits, as well as spontaneous hand movement loss. On the other hand, there are strong evidence that these individuals use the eyes with intentional purpose. Ten girls aged 4y8m to 12y10m with RS were assessed with a computer system for visual tracking regarding their ability of indicating with eyes the recognition of concepts of color (red, yellow and blue), shape (circle, square and triangle), size (big and small) and spatial position (over and under) to which they were first exposed to. Results from comparing the time of eyes fixation on required and not required concepts did not differ significantly. Children did not show with eyes the recognition of the required concepts when assessed with eye tracking system.
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Baptista PM, Mercadante MT, Macedo EC, Schwartzman JS. Cognitive performance in Rett syndrome girls: a pilot study using eyetracking technology. JOURNAL OF INTELLECTUAL DISABILITY RESEARCH : JIDR 2006; 50:662-6. [PMID: 16901293 DOI: 10.1111/j.1365-2788.2006.00818.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
BACKGROUND Rett syndrome (RS) is a pervasive developmental disorder with cognitive and neuromotor impairments (including loss of handiness and loss of communicative skills). OBJECTIVE To verify whether girls with RS use their gaze intentionally, by observing their performance in three cognitive tasks: (1) verbal instruction condition (look at picture X), (2) recognition and matching of pictures (look at the one that is the same), and (3) categorization of pictures (look at the one that is similar). METHOD Seven girls diagnosed with RS according to DSM-IV criteria were studied. Eyegaze technology was used to record the girls' eye movements' responses to visual stimulation. RESULTS The comparison of fixation time on the alternatives revealed a higher percentage (62.4%) of correct alternatives (chi(2) = 76.31; P = 0.000). Of the seven children assessed, only one did not present predominance of fixations on the correct alternatives in any one of the tasks. One did well in all tasks. Six responded correctly to all verbal instructions. CONCLUSION The rate of correct answers suggests that there is measurable and intentional gaze in RS girls and it can be used as a path to explore their cognitive performance.
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Affiliation(s)
- P M Baptista
- Development Disorders Program, Mackenzie Presbyterian University, São Paulo, Brazil.
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36
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Pardal-Fernández JM, Jerez-García P, Onsurbe-Ramírez I, Marco-Giner J. Rett syndrome: a case presenting with atypical seizures. Neurophysiological and clinical aspects. Neurophysiol Clin 2004; 34:49-57. [PMID: 15030800 DOI: 10.1016/j.neucli.2003.08.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2003] [Revised: 08/22/2003] [Accepted: 08/22/2003] [Indexed: 11/28/2022] Open
Abstract
OBJECTIVE To describe a specific electroclinical type of epileptic seizure in a patient with Rett syndrome. PATIENT AND METHODS We present the case of a girl with Rett syndrome and epilepsy, whose seizures followed two differentiated phases, namely (a) a brief hypertonic onset with tonic-axial predominance, followed by (b) a posterior prolonged clinical absence. These two phases were associated, respectively, to a paroxystic desynchronisation or generalised rapid spikes discharges, followed by a critical slow activity. CONCLUSIONS The epileptic seizures described in this report have not been previously documented in Rett syndrome. We review and discuss pathophysiological hypotheses in the light of this and previously reported cases of the syndrome.
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Affiliation(s)
- J M Pardal-Fernández
- Servicio Neurofisiología Clínica, Unidad de Electroencefalografía, Hospital General Universitario de Albacete. C/Hermanos Falcó no. 37, 02007 Albacete (España), Spain.
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37
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Abstract
Tradicionalmente, a inteligência é avaliada por instrumentos psicométricos. Em se tratando da avaliação cognitiva na primeira infância (0 a 36 meses de idade), os testes geralmente baseiam-se em critérios de desempenho psicomotor. Meio século de pesquisas tem demonstrado pouca ou nenhuma associação entre o que é requisitado nas escalas clássicas de desenvolvimento infantil e a performance cognitiva nos anos posteriores. Tais resultados fortaleceram a crença na descontinuidade do desenvolvimento da inteligência ao longo do ciclo vital. No entanto, há recentes evidências de que medidas de processamento de informação podem trazer respostas ao desafio de encontrar maiores correlações entre as pontuações em inteligência nos primeiros anos de vida e posteriores do que as obtidas por meio dos testes de desenvolvimento psicomotor. Índices de habituação visual e preferência pela novidade, bastante livres de requisitos motores, têm apresentado moderada validade preditiva em relação ao desenvolvimento cognitivo. No presente trabalho apresentam-se os principais estudos a esse respeito.
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Armstrong DD. Neuropathology of Rett syndrome. MENTAL RETARDATION AND DEVELOPMENTAL DISABILITIES RESEARCH REVIEWS 2002; 8:72-6. [PMID: 12112730 DOI: 10.1002/mrdd.10027] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Rett Syndrome is unlike any other pediatric neurologic disease, and its clinical-pathologic correlation can not be defined with standard histology techniques. Based on hypotheses suggested by careful clinical observations, the nervous system of the Rett child has been explored utilizing morphometry, golgi preparations, computerized tomography, magnetic resonance imaging, chemistry, immunocytochemistry, autoradiography, and molecular biologic techniques. From these many perspectives we conclude that Rett syndrome is not a typical degenerative disorder, storage disorder, nor the result of gross malformation, infectious or neoplastic processes. There remain regions of the brain that have not been studied in detail but the available data suggest that the neuropathology of Rett syndrome can be summarized as follows: the Rett brain is small for the age and the height of the patient; it does not become progressively smaller over three to four decades; it has small dendritic trees in pyramidal neurons of layers III and V in selected lobes (frontal, motor, and temporal); it has small neurons with an increased neuronal packing density; it has an immature expression of microtubular protein-2 and cyclooxygenase; it exhibits a changing pattern of neurotransmitter receptors with an apparent reduction in many neurotransmitters, possibly contributing to some symptomatology. A mutation in Mecp2 causes this unique disorder of brain development. Neuronal mosaicism for normal and mutated Mecp2 produces a consistent phenotype in the classic female patient and a small brain with some preserved islands of function, but with an inability to support hand use and speech. This paper summarizes our current observations about neuropathology of Rett syndrome. MRDD Research Reviews 2002;8:72-76.
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Abstract
Development and retention of speech is reported in 265 people with Rett syndrome: 30% (80) never gained real words, 55% (145) gained real words and lost them, 15%(40) retained some words and 6% of the total (16/265) continued to use phrases appropriately. Morphological studies of the cytoarchitecture of the speech areas in 14 cases indicate the existence of interhemispheric differences which form part of the infrastructure for speech processing. Ten adults with Rett syndrome and with meaningful speech are compared to age matched adults without speech. The profile of mind and strategies for coping with its problems are described by a family. Although the range in severity is wide the mental profile is remarkably consistent across the severity range with regard to both positive and negative aspects.
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Affiliation(s)
- A M Kerr
- Department of Psychological Medicine, University of Glasgow, Gartnavel Royal Hospital, 1055 Great Western Road, G21 0XH, Glasgow, UK.
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Moldavsky M, Lev D, Lerman-Sagie T. Behavioral phenotypes of genetic syndromes: a reference guide for psychiatrists. J Am Acad Child Adolesc Psychiatry 2001; 40:749-61. [PMID: 11437013 DOI: 10.1097/00004583-200107000-00009] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE To review the literature on behavioral phenotypes of genetic syndromes, displaying the data as a reference guide for everyday practice. METHOD A computerized search was performed for articles published in the past 10 years, and selected papers were surveyed. RESULTS The behavioral phenotypes of 11 major genetic syndromes were reviewed including the following topics: genetic etiology, genetic counseling, physical features, medical problems, cognitive and behavioral profile, and psychopathology. The speculated correlation between the identified gene and the pathophysiology of the cognitive and behavioral features is discussed. CONCLUSIONS Updated knowledge of behavioral phenotypes will help psychiatrists identify these conditions, refer the patient and his/her family for genetic diagnosis and counseling, make specific treatment recommendations, and contribute to research and syndrome delineation.
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Affiliation(s)
- M Moldavsky
- Pediatric Psychiatry Unit, Wolfson Medical Center, Holon, Israel.
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41
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Pillion JP, Rawool VW, Naidu S. Auditory brainstem responses in Rett syndrome: effects of hyperventilation, seizures, and tympanometric variables. AUDIOLOGY : OFFICIAL ORGAN OF THE INTERNATIONAL SOCIETY OF AUDIOLOGY 2000; 39:80-7. [PMID: 10882046 DOI: 10.3109/00206090009073057] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
This study examined the effects of tympanometric variables, stage of disease, hyperventilation, and seizures on the auditory brainstem response (ABR) in Rett syndrome (RS). Thirty-four female children with RS ranging in age from 2 years, 3 months to 15 years, 7 months participated in the study. ABRs and tympanograms were recorded from all of the subjects. When the ABR peaks were identifiable, interpeak latency intervals (IPLIs) for I-III, III-V, and I-V were computed for each waveform. The peaks (I, III, and V) and IPLIs were characterized as abnormal if either the peaks were absent or the latencies were greater than 2 SD from the normative data (obtained on female children). Analyses revealed significant prolongation of wave I latencies in Rett children with abnormal tympanograms. ABR wave III latencies were significantly affected by the presence of seizures and hyperventilation. The Pearson chi-square statistic revealed significant differences in the rate of wave III and V abnormalities due to the presence and degree of hyperventilation and the presence of seizures. Wave I abnormalities were also observed in the presence of normal middle ear function, suggesting the presence of sensorineural hearing impairment in some RS children. Clinical implications of these findings are discussed.
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Affiliation(s)
- J P Pillion
- Department of Audiology, Kennedy Krieger Institute, Baltimore, Maryland 21205, USA
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43
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Zappella M, Gillberg C, Ehlers S. The preserved speech variant: a subgroup of the Rett complex: a clinical report of 30 cases. J Autism Dev Disord 1998; 28:519-26. [PMID: 9932238 DOI: 10.1023/a:1026052128305] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Thirty girls and young women, 6 from Sweden and 24 from Italy, are described in this paper. They ranged in age from 5 through 28 years. All but one of the cases met full symptom criteria for DSM-IV autistic disorder. However, they also showed many features of classic Rett syndrome (RS) as outlined by the Rett syndrome Diagnostic Criteria Work Group. All met the required 3 out of 6 main criteria and 47% also met both these and the required 5 out of 11 supportive criteria for RS variants as outlined by Hagberg. The course of the disorder was more benign than in classic RS, but all the girls were severely functionally impaired. There was familial clustering in a subgroup. It is concluded that these 30 cases represent a syndrome, similar and probably related, to classic RS. It is suggested that there is a spectrum of syndromes ranging from severe cases with classical presentation to considerably milder variants. We propose that, at the present state of knowledge, these conditions might be best categorized as subgroups of the "Rett Complex," in which classical RS and the preserved speech variant may be the most frequent.
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Affiliation(s)
- M Zappella
- Department of Child Neuropsychiatry, General Hospital of Siena, Italy
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44
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Jacobsen K, Magnussen S, Smith L. Hidden visual capabilities in mentally retarded subjects diagnosed as deaf-blind. Vision Res 1997; 37:2931-5. [PMID: 9415371 DOI: 10.1016/s0042-6989(97)00098-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The visual acuity of twelve multi-handicapped, mentally retarded subjects, diagnosed as deaf-blind, was measured on two occasions with the Teller Acuity Cards (TAC). Eight subjects scored above the criterion for legally blind and the results of six of these indicated various degrees of poor to approaching-normal eyesight. To evaluate high-level vision four subjects were tested with the Fagan Test, assessing visual recognition memory for faces subsequent to familiarization with the preferential looking technique. The results for three subjects showed evidence for perceptual recognition. It is concluded that TAC combined with the Fagan Test may detect perceptual capacities unnoticed by clinical observation.
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Affiliation(s)
- K Jacobsen
- Department of Psychology, University of Oslo, Norway.
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45
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Skjeldal OH, von Tetzchner S, Aspelund F, Herder GA, Lofterłd B. Rett syndrome: geographic variation in prevalence in Norway. Brain Dev 1997; 19:258-61. [PMID: 9187475 DOI: 10.1016/s0387-7604(97)00572-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The prevalence of Rett syndrome is reported for three Norwegian counties (Rogaland, Ostfold and Nordland). The total number of females between 3 and 19 years of age in these counties was 96,920, and among these 21 females with Rett syndrome were identified, yielding a prevalence rate for Rett syndrome of 2.17 per 10,000 girls. One reason for this comparatively high prevalence rate might be that the full spectrum of Rett syndrome variants was included. The quality of the health care system and the awareness of Rett syndrome and its variants among Norwegians physicians also make it unlikely that many case were missed. However, the high total prevalence was caused by a statistically significant larger number of girls with Rett syndrome in Rogaland than in the other two counties. Sixteen of the girls were identified in Rogaland county, which gives a prevalence rate for this county of 3.77 per 10,000 girls. The prevalence rates in the two other counties were 1.05 and 0.77 per 10,000 girls. The geographical distribution of girls with Rett syndrome in Rogaland is probably due to genetic clustering. Geographical mobility in Norway is limited and many families have lived in the same geographical area for generations. An explanation based on genetic clustering is also supported by the fact that several of the girls with Rett syndrome in Rogaland county are known to be related.
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Affiliation(s)
- O H Skjeldal
- Department of Pediatrics, University of Oslo, Rikshospitalet, Norway.
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