Russell J Schachar

Summary

Affiliation: The Hospital for Sick Children
Country: Canada

Publications

  1. ncbi request reprint Evidence for an error monitoring deficit in attention deficit hyperactivity disorder
    Russell J Schachar
    Brain and Behavior Program, Research Institute, and Department of Psychiatry, University of Toronto, The Hospital for Sick Children, Toronto, Canada
    J Abnorm Child Psychol 32:285-93. 2004
  2. ncbi request reprint Inhibition of motor responses in siblings concordant and discordant for attention deficit hyperactivity disorder
    Russell J Schachar
    Department of Psychiatry, The Hospital for Sick Children, University of Toronto, Toronto M5N 2L1, Canada
    Am J Psychiatry 162:1076-82. 2005
  3. ncbi request reprint Restraint and cancellation: multiple inhibition deficits in attention deficit hyperactivity disorder
    Russell Schachar
    Psychiatry Research Unit, Department of Psychiatry, Brain and Behavior Programme, Research Institute, The Hospital for Sick Children, University of Toronto, 555 University Avenue, Toronto, Ontario, Canada
    J Abnorm Child Psychol 35:229-38. 2007
  4. doi request reprint Validation and extension of the endophenotype model in ADHD patterns of inheritance in a family study of inhibitory control
    Lisa M Goos
    Psychiatry Research, Hospital for Sick Children, 555 University Ave, Toronto, Ontario M5G 1X8, Canada
    Am J Psychiatry 166:711-7. 2009
  5. doi request reprint Heritability of response inhibition in children
    Russell J Schachar
    Neurosciences and Mental Health Programme, Research Institute and the Department of Psychiatry, The Hospital for Sick Children and University of Toronto, Toronto, Canada
    J Int Neuropsychol Soc 17:238-47. 2011
  6. ncbi request reprint Attention deficit hyperactivity disorder symptoms and response inhibition after closed head injury in children: do preinjury behavior and injury severity predict outcome?
    Russell Schachar
    Brain and Behavior, Research Institute, Hospital for Sick Children, Toronto, Ontario, Canada
    Dev Neuropsychol 25:179-98. 2004
  7. ncbi request reprint Association study for genes at chromosome 5p13-q11 in attention deficit hyperactivity disorder
    Nancy Laurin
    Genetics and Development Division, The Toronto Western Research Institute, University Health Network, Toronto, Ontario, Canada
    Am J Med Genet B Neuropsychiatr Genet 147:600-5. 2008
  8. ncbi request reprint Performance monitoring and response inhibition in anxiety disorders with and without comorbid ADHD
    Chana B Korenblum
    Brain and Behaviour Programme, Research Institute, and Department of Psychiatry, University of Toronto, The Hospital for Sick Children, Toronto, Ontario, Canada
    Depress Anxiety 24:227-32. 2007
  9. ncbi request reprint Attention-deficit hyperactivity disorder with and without obsessive-compulsive behaviours: clinical characteristics, cognitive assessment, and risk factors
    Paul Daniel Arnold
    Neurogenetics Section, Child Psychiatry Program, Centre for Addiction and Mental Health, Toronto, Ontario
    Can J Psychiatry 50:59-66. 2005
  10. ncbi request reprint Validating psychiatric endophenotypes: inhibitory control and attention deficit hyperactivity disorder
    Jennifer Crosbie
    Department of Psychiatry, Research Institute, The Hospital for Sick Children, University of Toronto, 555 University Avenue, Torento, Canada M5G 1X8
    Neurosci Biobehav Rev 32:40-55. 2008

Collaborators

Detail Information

Publications41

  1. ncbi request reprint Evidence for an error monitoring deficit in attention deficit hyperactivity disorder
    Russell J Schachar
    Brain and Behavior Program, Research Institute, and Department of Psychiatry, University of Toronto, The Hospital for Sick Children, Toronto, Canada
    J Abnorm Child Psychol 32:285-93. 2004
    ....
  2. ncbi request reprint Inhibition of motor responses in siblings concordant and discordant for attention deficit hyperactivity disorder
    Russell J Schachar
    Department of Psychiatry, The Hospital for Sick Children, University of Toronto, Toronto M5N 2L1, Canada
    Am J Psychiatry 162:1076-82. 2005
    ..The authors sought to determine whether nonaffected siblings of ADHD probands have a motor response inhibition deficit and to assess concordance for this inhibition deficit in ADHD-concordant and ADHD-discordant sibling pairs...
  3. ncbi request reprint Restraint and cancellation: multiple inhibition deficits in attention deficit hyperactivity disorder
    Russell Schachar
    Psychiatry Research Unit, Department of Psychiatry, Brain and Behavior Programme, Research Institute, The Hospital for Sick Children, University of Toronto, 555 University Avenue, Toronto, Ontario, Canada
    J Abnorm Child Psychol 35:229-38. 2007
    ..We conclude that ADHD is associated with deficits in both restraint and cancellation subcomponents of inhibition...
  4. doi request reprint Validation and extension of the endophenotype model in ADHD patterns of inheritance in a family study of inhibitory control
    Lisa M Goos
    Psychiatry Research, Hospital for Sick Children, 555 University Ave, Toronto, Ontario M5G 1X8, Canada
    Am J Psychiatry 166:711-7. 2009
    ..In this study, the authors sought to extend the endophenotype model and further demonstrate its utility by investigating the parental origin of shared genetic risk in ADHD...
  5. doi request reprint Heritability of response inhibition in children
    Russell J Schachar
    Neurosciences and Mental Health Programme, Research Institute and the Department of Psychiatry, The Hospital for Sick Children and University of Toronto, Toronto, Canada
    J Int Neuropsychol Soc 17:238-47. 2011
    ..Response variability was not heritable. These results support the potential of response inhibition and latency as endophenotypes in genetic research...
  6. ncbi request reprint Attention deficit hyperactivity disorder symptoms and response inhibition after closed head injury in children: do preinjury behavior and injury severity predict outcome?
    Russell Schachar
    Brain and Behavior, Research Institute, Hospital for Sick Children, Toronto, Ontario, Canada
    Dev Neuropsychol 25:179-98. 2004
    ..Poor response inhibition is a consequence of CHI but only when the CHI is severe and the child manifests high levels of SADHD symptoms...
  7. ncbi request reprint Association study for genes at chromosome 5p13-q11 in attention deficit hyperactivity disorder
    Nancy Laurin
    Genetics and Development Division, The Toronto Western Research Institute, University Health Network, Toronto, Ontario, Canada
    Am J Med Genet B Neuropsychiatr Genet 147:600-5. 2008
    ..Our results suggest that these six genes are unlikely to be susceptibility genes in the chromosome 5p13-q11 region and other genes should now be considered for priority study...
  8. ncbi request reprint Performance monitoring and response inhibition in anxiety disorders with and without comorbid ADHD
    Chana B Korenblum
    Brain and Behaviour Programme, Research Institute, and Department of Psychiatry, University of Toronto, The Hospital for Sick Children, Toronto, Ontario, Canada
    Depress Anxiety 24:227-32. 2007
    ..ANX was not associated with performance monitoring or inhibition deficits once comorbid ADHD was considered. This emphasizes the importance of controlling for comorbid ADHD in studies of cognition and anxiety...
  9. ncbi request reprint Attention-deficit hyperactivity disorder with and without obsessive-compulsive behaviours: clinical characteristics, cognitive assessment, and risk factors
    Paul Daniel Arnold
    Neurogenetics Section, Child Psychiatry Program, Centre for Addiction and Mental Health, Toronto, Ontario
    Can J Psychiatry 50:59-66. 2005
    ....
  10. ncbi request reprint Validating psychiatric endophenotypes: inhibitory control and attention deficit hyperactivity disorder
    Jennifer Crosbie
    Department of Psychiatry, Research Institute, The Hospital for Sick Children, University of Toronto, 555 University Avenue, Torento, Canada M5G 1X8
    Neurosci Biobehav Rev 32:40-55. 2008
    ..The literature on motor response inhibition is reviewed to illustrate the validation process which is recommended in the selection of other candidate endophenotypes...
  11. ncbi request reprint Using the Conners' Teacher Rating Scale-Revised in school children referred for assessment
    Alice Charach
    Research Institute, Department of Psychiatry, Hospital for Sick Children, Toronto, Ontario, Canada
    Can J Psychiatry 54:232-41. 2009
    ..We hypothesized that extreme scale values would increase diagnostic certainty and that classification errors would be associated with comorbid conditions...
  12. pmc Why IQ is not a covariate in cognitive studies of neurodevelopmental disorders
    Maureen Dennis
    Department of Psychology, The Hospital for Sick Children, Toronto, Ontario, Canada
    J Int Neuropsychol Soc 15:331-43. 2009
    ....
  13. doi request reprint Stop signal and Conners' continuous performance tasks: test--retest reliability of two inhibition measures in ADHD children
    Noam Soreni
    University of Toronto, Ontario, Canada
    J Atten Disord 13:137-43. 2009
    ..To measure test-retest reliability of the Stop-Signal Task (SST) and the Conners' Continuous Performance Test (CPT) in children with ADHD...
  14. doi request reprint Is the behavior rating inventory of executive function more strongly associated with measures of impairment or executive function?
    Tara McAuley
    Department of Psychiatry Research, The Hospital for Sick Children, Toronto, Ontario, Canada M5G 1X8
    J Int Neuropsychol Soc 16:495-505. 2010
    ..These findings support the use of the BRIEF as a clinical tool for assessing a broad range of concerns, but raise questions about the relation of the BRIEF to performance-based tasks that are commonly used to assess executive function...
  15. ncbi request reprint Investigation of the G protein subunit Galphaolf gene (GNAL) in attention deficit/hyperactivity disorder
    Nancy Laurin
    Cell and Molecular Biology Division, Toronto Western Research Institute, University Health Network, Toronto, Ont, Canada
    J Psychiatr Res 42:117-24. 2008
    ..005) and rs8098539A (P=0.035). These preliminary findings suggest a possible contribution of GNAL in the susceptibility to ADHD, with possible involvement of parent-of-origin effects...
  16. ncbi request reprint Parent-of-origin effects in attention-deficit hyperactivity disorder
    Lisa M Goos
    Department of Psychiatry, The Hospital for Sick Children, Toronto, Ontario, Canada M5G 1X8
    Psychiatry Res 149:1-9. 2007
    ..Interpretations of these data in terms of environmental and genetic factors, including epigenetic and sex-linked hypotheses, are explored...
  17. pmc Puppets, robots, critics, and actors within a taxonomy of attention for developmental disorders
    Maureen Dennis
    Program in Neurosciences and Mental Health, The Hospital for Sick Children, Toronto, Canada
    J Int Neuropsychol Soc 14:673-90. 2008
    ....
  18. ncbi request reprint The serotonin receptor HTR1B: gene polymorphisms in attention deficit hyperactivity disorder
    Abel Ickowicz
    The Hospital for Sick Children, Toronto, Ontario, Canada
    Am J Med Genet B Neuropsychiatr Genet 144:121-5. 2007
    ..In addition we did not find evidence to suggest an association between HTR1B and perfectionism in this sample of ADHD families...
  19. ncbi request reprint Stimulant treatment over five years: adherence, effectiveness, and adverse effects
    Alice Charach
    Department of Psychiatry, The Hospital for Sick Children and the University of Toronto, Research Institute, The Hospital for Sick Children, University of Toronto, Ontario, Canada
    J Am Acad Child Adolesc Psychiatry 43:559-67. 2004
    ..To evaluate the impact of adherence and medication status on effectiveness and adverse effects of stimulant use in children with attention-deficit/hyperactivity disorder (ADHD) over 5 years...
  20. ncbi request reprint Stimulant treatment over 5 years: effects on growth
    Alice Charach
    Department of Psychiatry, The Hospital for Sick Children, Toronto, Ontario, Canada
    J Am Acad Child Adolesc Psychiatry 45:415-21. 2006
    ..Long-term effects of psychostimulants on growth in height and in weight are investigated in children with attention-deficit/hyperactivity disorder...
  21. ncbi request reprint Correlates of methylphenidate use in Canadian children: a cross-sectional study
    Alice Charach
    Department of Psychiatry, Hospital for Sick Children, Toronto, Ontario
    Can J Psychiatry 51:17-26. 2006
    ..This study aimed to estimate the prevalence of methylphenidate (MPH) use among Canadian children aged 2 to 11 years, from 1994-1995 to 1998-1999 and to identify sociodemographic, child, and parent-family correlates are identified...
  22. ncbi request reprint The development of selective inhibitory control across the life span
    Anne Claude Bedard
    The Hospital for Sick Children, Toronto, Canada
    Dev Neuropsychol 21:93-111. 2002
    ..Findings are discussed in regard to the decay and maturation of selective inhibitory control across the life span...
  23. ncbi request reprint Response inhibition after traumatic brain injury (TBI) in children: impairment and recovery
    Nancy Leblanc
    Department of Psychiatry, Brain and Behaviour Programme, The Hospital for Sick Children, University of Toronto, Canada
    Dev Neuropsychol 28:829-48. 2005
    ..Replication with longitudinal testing of a comparison group of children sustaining extracranial injury is necessary to confirm our findings...
  24. doi request reprint Neuropsychological performance in childhood OCD: a preliminary study
    Tisha J Ornstein
    Department of Psychology, Ryerson University, Toronto, Ontario, Canada
    Depress Anxiety 27:372-80. 2010
    ..Neuropsychological deficits have often been found in studies of adults with obsessive compulsive disorder (OCD). However, few studies have examined such impairment in children with OCD and of those studies published, the results are mixed...
  25. doi request reprint Cognitive and behavioral effects of multilayer-release methylphenidate in the treatment of children with attention-deficit/hyperactivity disorder
    Russell Schachar
    Hospital for Sick Children, Toronto, Ontario, Canada
    J Child Adolesc Psychopharmacol 18:11-24. 2008
    ....
  26. doi request reprint Error detection in the stop signal task
    Andre Chevrier
    Department of Psychiatry, The Hospital for Sick Children, Toronto, Ontario, Canada
    Neuroimage 53:664-73. 2010
    ....
  27. ncbi request reprint Association study of the brain-derived neurotropic factor (BDNF) gene in attention deficit hyperactivity disorder
    Jonghun Lee
    Cell and Molecular Biology Division, Toronto Western Research Institute, University Health Network, Toronto, Ontario, Canada
    Am J Med Genet B Neuropsychiatr Genet 144:976-81. 2007
    ..651, P = 0.008). These results should be interpreted cautiously, however, because of the low haplotype frequency. In light of the evidence for an involvement of BDNF in ADHD, further analysis of the BDNF gene in ADHD is warranted...
  28. ncbi request reprint Dissociation of response inhibition and performance monitoring in the stop signal task using event-related fMRI
    Andre D Chevrier
    Brain and Behaviour Programme, Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada
    Hum Brain Mapp 28:1347-58. 2007
    ..Our results confirm that there are distinct aspects of inhibition and performance monitoring functions which come into play at various phases within a given trial of the SST, and that these are separable using fMRI...
  29. ncbi request reprint Gene for the serotonin transporter and ADHD: no association with two functional polymorphisms
    Karen G Wigg
    Department of Psychiatry, Cell and Molecular Division, The Toronto Western Hospital, University Health Network, Toronto, Ontario, Canada
    Am J Med Genet B Neuropsychiatr Genet 141:566-70. 2006
    ..These polymorphisms were genotyped in 209 ADHD families identified through an affected proband. We did not find evidence for an association of these polymorphisms, or haplotypes of these polymorphisms, to ADHD in this sample...
  30. ncbi request reprint Selective inhibition in children with attention-deficit hyperactivity disorder off and on stimulant medication
    Anne Claude Bedard
    Institute of Medical Science, The University of Toronto, Toronto, Canada
    J Abnorm Child Psychol 31:315-27. 2003
    ..On the one hand, findings are consistent with purported inhibition deficit in ADHD, but on the other hand, suggest that neither the impairment itself, nor MPH effects, were restricted to inhibition...
  31. ncbi request reprint The parent interview for child symptoms: a situation-specific clinical research interview for attention-deficit hyperactivity and related disorders
    Abel Ickowicz
    Department of Psychiatry, Hospital for Sick Children, Toronto, Ontario
    Can J Psychiatry 51:325-8. 2006
    ..To describe the properties of a semistructured research interview of parents designed to evaluate attention-deficit hyperactivity disorder (ADHD) and related psychopathology...
  32. doi request reprint Association of the dopamine transporter gene and ADHD symptoms in a Canadian population-based sample of same-age twins
    Isabelle Ouellet-Morin
    Genetics and Development Division, Toronto Western Research Institute, University Health Network, Toronto, Canada
    Am J Med Genet B Neuropsychiatr Genet 147:1442-9. 2008
    ..These findings indicate that the DAT1 gene contributes to ADHD symptoms in this sample and further suggest that the VNTR may not be the optimal polymorphism for study in all populations...
  33. ncbi request reprint Replication test for association of the IL-1 receptor antagonist gene, IL1RN, with attention-deficit/hyperactivity disorder
    Virginia L Misener
    Cell and Molecular Biology Division, Toronto Western Research Institute, University Health Network, Toronto, Ont, Canada
    Neuropsychobiology 50:231-4. 2004
    ..e. false-positive) result. These findings highlight the need for further investigations of this marker, in additional independent ADHD samples, in the future...
  34. doi request reprint Association of attention-deficit/hyperactivity disorder with a candidate region for reading disabilities on chromosome 6p
    Jillian M Couto
    Genetics and Development Division, Toronto Western Research Institute, Toronto Western Hospital, University Health Network, Toronto, Canada
    Biol Psychiatry 66:368-75. 2009
    ..RD has been previously associated with five genes in the region, particularly DCDC2 and KIAA0319...
  35. ncbi request reprint Sequence variation in the 3'-untranslated region of the dopamine transporter gene and attention-deficit hyperactivity disorder (ADHD)
    Yu Feng
    Cell and Molecular Biology Division, Toronto Western Research Institute, University Health Network, Toronto, Ontario, Canada
    Am J Med Genet B Neuropsychiatr Genet 139:1-6. 2005
    ..Our results therefore refute the possibility of the reported DraI variation or alleles of the VNTR as the functional variants contributing to the disorder...
  36. ncbi request reprint Attention deficit hyperactivity disorder and the gene for dopamine Beta-hydroxylase
    Karen Wigg
    Department of Psychiatry, Toronto Western Hospital, Ont, Canada
    Am J Psychiatry 159:1046-8. 2002
    ..One recent study reported an association of an allele of the TaqI polymorphism located in the fifth intron of the gene for dopamine beta-hydroxylase (DBH). The authors' goal was to replicate this finding...
  37. ncbi request reprint The gene for synapsin III and attention-deficit hyperactivity disorder
    Rohit Makkar
    Cell and Molecular Biology Division, Toronto Western Research Institute, University Health Network, Toronto, Ontario, Canada
    Psychiatr Genet 17:109-12. 2007
    ..On the basis of the role of synapsin III in the modulation of neurotransmitter release, we tested this gene as a candidate contributing to the genetic susceptibility of attention deficit hyperactivity disorder...
  38. ncbi request reprint Attention-deficit hyperactivity disorder: critical appraisal of extended treatment studies
    Russell Schachar
    Department of Psychiatry, University of Toronto, Division of Child and Adolescent Psychiatry, Brain and Behaviour Program, Research Institute, Hospital for Sick Children, Toronto, Ontaro
    Can J Psychiatry 47:337-48. 2002
    ..Only 1 study showed that combination therapy adds to the effects of medication. Rigorous treatment research among representative samples of ADHD individuals is needed...
  39. ncbi request reprint Intraindividual variability of striatal (1)H-MRS brain metabolite measurements at 3 T
    Noam Soreni
    Psychiatry Research Unit, The Hospital for Sick Children, Toronto, Ontario, Canada M5G 1X8
    Magn Reson Imaging 24:187-94. 2006
    ..To measure possible positional and diurnal physiological effects on brain metabolites in single-voxel proton magnetic resonance spectroscopy ((1)H-MRS) measurements of the right and left striatum...
  40. ncbi request reprint No evidence for genetic association between DARPP-32 (PP1R1B) polymorphisms and attention deficit hyperactivity disorder
    Nancy Laurin
    Division of Genetics and Development, Toronto Western Research Institute, University Health Network, Toronto, ON, Canada
    Am J Med Genet B Neuropsychiatr Genet 147:339-42. 2008
    ..In conclusion, albeit a key regulatory role in dopamine signaling, our data do not support a major contribution of the DARPP-32 gene in ADHD...
  41. ncbi request reprint The norepinephrine transporter gene and attention-deficit hyperactivity disorder
    Cathy L Barr
    Department of Psychiatry and Division of Cellular and Molecular Biology, Toronto Western Hospital, University Health Network, Toronto, Ontario, Canada
    Am J Med Genet 114:255-9. 2002
    ..8%) was similar to that previously reported in a control sample (2.2%), it is unlikely that this variant is related to the ADHD phenotype. Our results do not support the NET1 gene as a major genetic susceptibility factor in ADHD...