J H Callicott

Summary

Affiliation: National Institutes of Health
Country: USA

Publications

  1. ncbi request reprint Neuropsychiatric dynamics: the study of mental illness using functional magnetic resonance imaging
    J H Callicott
    Clinical Brain Disorders Branch, National Institute of Mental Health, NIH, Bethesda, MD 20892, USA
    Eur J Radiol 30:95-104. 1999
  2. ncbi request reprint Complexity of prefrontal cortical dysfunction in schizophrenia: more than up or down
    Joseph H Callicott
    Clinical Brain Disorders Branch, NIMH NIH, Bldg 10, Rm 4D 20, MSC 1389, Bethesda, MD 20892 1389, USA
    Am J Psychiatry 160:2209-15. 2003
  3. ncbi request reprint Abnormal fMRI response of the dorsolateral prefrontal cortex in cognitively intact siblings of patients with schizophrenia
    Joseph H Callicott
    Clinical Brain Disorders Branch, IRP, NIMH, NIH, Bethesda, MD 20982 1389, USA
    Am J Psychiatry 160:709-19. 2003
  4. ncbi request reprint An expanded role for functional neuroimaging in schizophrenia
    Joseph H Callicott
    Unit on Functional MRI Clinical Brain Disorders, Branch NIMH NIH, Building 10, Room 4D 20, MSC 1389, Bethesda, MD 20892 1389, USA
    Curr Opin Neurobiol 13:256-60. 2003
  5. ncbi request reprint Physiological dysfunction of the dorsolateral prefrontal cortex in schizophrenia revisited
    J H Callicott
    Clinical Brain Disorders Branch, IRP, NIMH Laboratory of Diagnostic Radiology Research, CC, NIH, Bethesda, MD 20892 1389, USA
    Cereb Cortex 10:1078-92. 2000
  6. ncbi request reprint Selective relationship between prefrontal N-acetylaspartate measures and negative symptoms in schizophrenia
    J H Callicott
    Clinical Brain Disorders Branch, Intramural Research Program, NIMH, National Institutes of Health, Bethesda, MD 20892 1389, USA
    Am J Psychiatry 157:1646-51. 2000
  7. ncbi request reprint Prefrontal neurons and the genetics of schizophrenia
    D R Weinberger
    Clinical Brain Disorders Branch, Intramural Research Program, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland 20892, USA
    Biol Psychiatry 50:825-44. 2001
  8. ncbi request reprint Allelic variation in GAD1 (GAD67) is associated with schizophrenia and influences cortical function and gene expression
    R E Straub
    Clinical Brain Disorders Branch, Genes, Cognition, and Psychosis Program, Intramural Research Program, National Institute of Mental Health, NIH, US Department of Health and Human Services, Bethesda, MD 20892 1379, USA
    Mol Psychiatry 12:854-69. 2007
  9. ncbi request reprint Genetic variation in MAOA modulates ventromedial prefrontal circuitry mediating individual differences in human personality
    J W Buckholtz
    Neuroimaging Core Facility, National Institute for Mental Health, NIH, DHHS, Bethesda, MD 20892 1365, USA
    Mol Psychiatry 13:313-24. 2008
  10. ncbi request reprint Effects of dextroamphetamine on cognitive performance and cortical activation
    V S Mattay
    Clinical Brain Disorders Branch, Intramural Research Program, Laboratory of Diagnostic Radiology Research, Office of Intramural Research, National Institutes of Health, 9000 Rockville Pike, Bethesda, Maryland, 20892, USA
    Neuroimage 12:268-75. 2000

Detail Information

Publications48

  1. ncbi request reprint Neuropsychiatric dynamics: the study of mental illness using functional magnetic resonance imaging
    J H Callicott
    Clinical Brain Disorders Branch, National Institute of Mental Health, NIH, Bethesda, MD 20892, USA
    Eur J Radiol 30:95-104. 1999
    ..Finally, fMRI is being used to simplify the complex genetics of neuropsychiatric illness by generating quantitative and qualitative brain phenotypes...
  2. ncbi request reprint Complexity of prefrontal cortical dysfunction in schizophrenia: more than up or down
    Joseph H Callicott
    Clinical Brain Disorders Branch, NIMH NIH, Bldg 10, Rm 4D 20, MSC 1389, Bethesda, MD 20892 1389, USA
    Am J Psychiatry 160:2209-15. 2003
    ..The authors' goal was to explore this phenomenon...
  3. ncbi request reprint Abnormal fMRI response of the dorsolateral prefrontal cortex in cognitively intact siblings of patients with schizophrenia
    Joseph H Callicott
    Clinical Brain Disorders Branch, IRP, NIMH, NIH, Bethesda, MD 20982 1389, USA
    Am J Psychiatry 160:709-19. 2003
    ..Earlier family studies have suggested that deficits in executive cognition and working memory may be related to genetic susceptibility for schizophrenia, but the biological basis for this behavioral phenotype has not been identified...
  4. ncbi request reprint An expanded role for functional neuroimaging in schizophrenia
    Joseph H Callicott
    Unit on Functional MRI Clinical Brain Disorders, Branch NIMH NIH, Building 10, Room 4D 20, MSC 1389, Bethesda, MD 20892 1389, USA
    Curr Opin Neurobiol 13:256-60. 2003
    ..By examining recent findings and efforts to link these findings to genes, this article will review these exciting developments in schizophrenia research...
  5. ncbi request reprint Physiological dysfunction of the dorsolateral prefrontal cortex in schizophrenia revisited
    J H Callicott
    Clinical Brain Disorders Branch, IRP, NIMH Laboratory of Diagnostic Radiology Research, CC, NIH, Bethesda, MD 20892 1389, USA
    Cereb Cortex 10:1078-92. 2000
    ..These data suggest that under certain conditions the physiological ramifications of dorsal PFC neuronal pathology in schizophrenia includes exaggerated and inefficient cortical activity, especially of dorsal PFC...
  6. ncbi request reprint Selective relationship between prefrontal N-acetylaspartate measures and negative symptoms in schizophrenia
    J H Callicott
    Clinical Brain Disorders Branch, Intramural Research Program, NIMH, National Institutes of Health, Bethesda, MD 20892 1389, USA
    Am J Psychiatry 157:1646-51. 2000
    ..The authors hypothesized that an in vivo measure of prefrontal neuronal pathology (N:-acetylaspartate [NAA] levels) in patients with schizophrenia would predict negative symptoms...
  7. ncbi request reprint Prefrontal neurons and the genetics of schizophrenia
    D R Weinberger
    Clinical Brain Disorders Branch, Intramural Research Program, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland 20892, USA
    Biol Psychiatry 50:825-44. 2001
    ....
  8. ncbi request reprint Allelic variation in GAD1 (GAD67) is associated with schizophrenia and influences cortical function and gene expression
    R E Straub
    Clinical Brain Disorders Branch, Genes, Cognition, and Psychosis Program, Intramural Research Program, National Institute of Mental Health, NIH, US Department of Health and Human Services, Bethesda, MD 20892 1379, USA
    Mol Psychiatry 12:854-69. 2007
    ..These coincident results implicate GAD1 in the etiology of schizophrenia and suggest that the mechanism involves altered cortical GABA inhibitory activity, perhaps modulated by dopaminergic function...
  9. ncbi request reprint Genetic variation in MAOA modulates ventromedial prefrontal circuitry mediating individual differences in human personality
    J W Buckholtz
    Neuroimaging Core Facility, National Institute for Mental Health, NIH, DHHS, Bethesda, MD 20892 1365, USA
    Mol Psychiatry 13:313-24. 2008
    ....
  10. ncbi request reprint Effects of dextroamphetamine on cognitive performance and cortical activation
    V S Mattay
    Clinical Brain Disorders Branch, Intramural Research Program, Laboratory of Diagnostic Radiology Research, Office of Intramural Research, National Institutes of Health, 9000 Rockville Pike, Bethesda, Maryland, 20892, USA
    Neuroimage 12:268-75. 2000
    ..These heterogeneic effects of dextroamphetamine may be explained by genetic variations that interact with the effects of dextroamphetamine...
  11. pmc Epistatic interactions of AKT1 on human medial temporal lobe biology and pharmacogenetic implications
    H Y Tan
    Clinical Brain Disorders Branch, Genes, Cognition and Psychosis Program, Division of Intramural Research Programs, National Institute of Mental Health, Bethesda, MD 20892, USA
    Mol Psychiatry 17:1007-16. 2012
    ....
  12. ncbi request reprint Impact of complex genetic variation in COMT on human brain function
    A Meyer-Lindenberg
    Unit for Systems Neuroscience in Psychiatry, National Institute of Mental Health, NIH, DHHS, Bethesda, MD 20892 1257, USA
    Mol Psychiatry 11:867-77, 797. 2006
    ..This work provides an in vivo approach to functional validation in brain of the biological impact of complex genetic variations within a gene that may be critical for its clinical association...
  13. pmc Effect of COMT Val108/158 Met genotype on frontal lobe function and risk for schizophrenia
    M F Egan
    Clinical Brain Disorders Branch, Building 10, Center Drive, National Institute of Mental Health, Bethesda, MD 20892, USA
    Proc Natl Acad Sci U S A 98:6917-22. 2001
    ..These data suggest that the COMT Val allele, because it increases prefrontal dopamine catabolism, impairs prefrontal cognition and physiology, and by this mechanism slightly increases risk for schizophrenia...
  14. ncbi request reprint Neurophysiological correlates of age-related changes in human motor function
    V S Mattay
    Clinical Brain Disorders Branch, Intramural Research Program, National Institute of Mental Health, NIH, Bethesda, MD 20892 1379, USA
    Neurology 58:630-5. 2002
    ..There are well-defined and characteristic age-related deficits in motor abilities that may reflect structural and chemical changes in the aging brain...
  15. pmc Genetic variation in AKT1 is linked to dopamine-associated prefrontal cortical structure and function in humans
    Hao Yang Tan
    Clinical Brain Disorders Branch, Genes, Cognition and Psychosis Program, Division of Intramural Research Programs, National Institute of Mental Health, NIH, Bethesda, Maryland 20892, USA
    J Clin Invest 118:2200-8. 2008
    ..These data implicate AKT1 in modulating human prefrontal-striatal structure and function and suggest that the mechanism of this effect may be coupled to dopaminergic signaling and relevant to the expression of psychosis...
  16. ncbi request reprint Prefrontal dysfunction in schizophrenia controlling for COMT Val158Met genotype and working memory performance
    Alessandro Bertolino
    Psychiatric Neuroscience Group, Section on Mental Disorders, Department of Psychiatric and Neurological Sciences, University of Bari, Bari, Italy
    Psychiatry Res 147:221-6. 2006
    ..We also replicated earlier findings that the Val allele of the COMT polymorphism is associated with greater engagement of the prefrontal cortex...
  17. ncbi request reprint Tolcapone improves cognition and cortical information processing in normal human subjects
    Jose A Apud
    Genes, Cognition and Psychosis Program, Clinical Brain Disorders Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, MD 20854, USA
    Neuropsychopharmacology 32:1011-20. 2007
    ..Our results are consistent with data from animal studies and from computational models of the effects of selective enhancement of DA signaling in the prefrontal cortex...
  18. ncbi request reprint Instability of prefrontal signal processing in schizophrenia
    Georg Winterer
    Genes, Cognition and Psychosis Program, NIH, NIMH, 10 Center Dr, MSC 1379, Bethesda, MD 20892, USA
    Am J Psychiatry 163:1960-8. 2006
    ....
  19. ncbi request reprint Dysfunctional prefrontal regional specialization and compensation in schizophrenia
    Hao Yang Tan
    Unit on Functional MRI, Clinical Brain Disorders Branch, Intramural Research Program, National Institute of Mental Health, 10 Center Dr, Rm 4C 216, MSC 1364, Bethesda, MD 20892 1364, USA
    Am J Psychiatry 163:1969-77. 2006
    ....
  20. pmc Genetic evidence implicating DARPP-32 in human frontostriatal structure, function, and cognition
    Andreas Meyer-Lindenberg
    Unit for Systems Neuroscience in Psychiatry, Neuroimaging Core Facility, and Clinical Brain Disorders Branch, Genes, Cognition, and Psychosis Program, National Institute for Mental Health NIMH, NIH, Bethesda, MD 20892, USA
    J Clin Invest 117:672-82. 2007
    ..Our convergent results identify a prefrontal-neostriatal system affected by variation in PPP1R1B and suggest that DARPP-32 plays a pivotal role in cognitive function and possibly in the pathogenesis of schizophrenia...
  21. ncbi request reprint Allelic variation in RGS4 impacts functional and structural connectivity in the human brain
    Joshua W Buckholtz
    Clinical Brain Disorders Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland 20892 1364, USA
    J Neurosci 27:1584-93. 2007
    ..These findings suggest mechanisms in brain for the association of RGS4 with risk for psychiatric illness...
  22. pmc Enuresis as a premorbid developmental marker of schizophrenia
    Thomas M Hyde
    Clinical Brain Disorders Branch, NIMH DIRP NIH, Bethesda, MD 20892, USA
    Brain 131:2489-98. 2008
    ..These findings add to the evidence implicating prefrontal dysmaturation in this disorder, potentially related to genetic risk factors...
  23. pmc Epistasis between catechol-O-methyltransferase and type II metabotropic glutamate receptor 3 genes on working memory brain function
    Hao Yang Tan
    Genes, Cognition, and Psychosis Program, Clinical Brain Disorders Branch, National Institute of Mental Health Intramural Research Program, National Institutes of Health, Bethesda, MD 20892, USA
    Proc Natl Acad Sci U S A 104:12536-41. 2007
    ..These findings extend putative brain dopaminergic and glutamatergic relationships indexed by COMT and GRM3 to a systems-level interaction in human cortical circuits implicated in working memory dysfunction such as in schizophrenia...
  24. pmc Is gray matter volume an intermediate phenotype for schizophrenia? A voxel-based morphometry study of patients with schizophrenia and their healthy siblings
    Robyn A Honea
    Genes, Cognition and Psychosis Program, National Institute of Mental Health, Division of Intramural Research, National Institutes of Health, Department of Health and Human Services, Bethesda, Maryland 20892 1364, USA
    Biol Psychiatry 63:465-74. 2008
    ..We sought to discover previously unidentified gray matter volume differences in patients with schizophrenia and their siblings with optimized voxel-based morphometry...
  25. ncbi request reprint Dysfunctional and compensatory prefrontal cortical systems, genes and the pathogenesis of schizophrenia
    Hao Yang Tan
    Genes, Cognition and Psychosis Program, Clinical Brain Disorders Branch, National Institute of Mental Health, NIH, Bethesda, MD 20892, USA
    Cereb Cortex 17:i171-81. 2007
    ....
  26. pmc Variation in DISC1 affects hippocampal structure and function and increases risk for schizophrenia
    Joseph H Callicott
    Genes, Cognition, and Psychosis Program, Clinical Brain Disorders Branch, Division of Intramural Research, National Institute of Mental Health, National Institutes of Health, Bethesda, MD 20892, USA
    Proc Natl Acad Sci U S A 102:8627-32. 2005
    ....
  27. ncbi request reprint Catechol-O-methyltransferase Val158Met modulation of prefrontal-parietal-striatal brain systems during arithmetic and temporal transformations in working memory
    Hao Yang Tan
    Clinical Brain Disorders Branch, Genes Cognition and Psychosis Program, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland 20892, USA
    J Neurosci 27:13393-401. 2007
    ..These findings add to the integration of dopaminergic signaling in basic cortical assemblies with their roles in specific human brain networks during the orchestration of information processing in WM...
  28. pmc The evolutionarily conserved G protein-coupled receptor SREB2/GPR85 influences brain size, behavior, and vulnerability to schizophrenia
    Mitsuyuki Matsumoto
    Drug Discovery Research, Astellas Pharma Inc, Tsukuba, Ibaraki 305 8585, Japan
    Proc Natl Acad Sci U S A 105:6133-8. 2008
    ..Our data implicate SREB2 as a potential risk factor for psychiatric disorders and its pathway as a target for psychiatric therapy...
  29. ncbi request reprint Working memory deficits and levels of N-acetylaspartate in patients with schizophreniform disorder
    Alessandro Bertolino
    Department of Psychiatry and Neurological Sciences, University of Bari, Italy
    Am J Psychiatry 160:483-9. 2003
    ..In addition, they assessed the relationship between N-acetylaspartate levels and working memory deficits...
  30. pmc Neural mechanisms of genetic risk for impulsivity and violence in humans
    Andreas Meyer-Lindenberg
    Unit for Systems Neuroscience in Psychiatry, Neuroimaging Core Facility, National Institutes of Health, Department of Health and Human Services, 9000 Rockville Pike, Bethesda, MD 20892 1365, USA
    Proc Natl Acad Sci U S A 103:6269-74. 2006
    ....
  31. ncbi request reprint Dopaminergic modulation of cortical function in patients with Parkinson's disease
    Venkata S Mattay
    Clinical Brain Disorders Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, MD 20982 1379, USA
    Ann Neurol 51:156-64. 2002
    ....
  32. pmc Catechol O-methyltransferase val158-met genotype and individual variation in the brain response to amphetamine
    Venkata S Mattay
    Clinical Brain Disorders Branch, National Institute of Mental Health, National Institutes of Health, Department of Health and Human Services, Building 10, Center Drive, Room 4s 235, Bethesda, MD 20982 1379, USA
    Proc Natl Acad Sci U S A 100:6186-91. 2003
    ..Further, individuals with the met/met catechol O-methyltransferase genotype appear to be at increased risk for an adverse response to amphetamine...
  33. ncbi request reprint Neuronal pathology in the hippocampal area of patients with bipolar disorder: a study with proton magnetic resonance spectroscopic imaging
    Alessandro Bertolino
    Clinical Brain Disorders Branch, Intramural Research Programs, National Institutes of Health, Bethesda, Maryland 20892, USA
    Biol Psychiatry 53:906-13. 2003
    ..The objective of this study was to assess possible NAA reductions in hippocampus and prefrontal regions in patients with bipolar disorder...
  34. ncbi request reprint The BDNF val66met polymorphism affects activity-dependent secretion of BDNF and human memory and hippocampal function
    Michael F Egan
    Clinical Brain Disorders Branch, National Institute of Mental Health, Room 4s 235, 10 Center Drive, Bethesda, MD 20892, USA
    Cell 112:257-69. 2003
    ..These results demonstrate a role for BDNF and its val/met polymorphism in human memory and hippocampal function and suggest val/met exerts these effects by impacting intracellular trafficking and activity-dependent secretion of BDNF...
  35. ncbi request reprint Brain-derived neurotrophic factor val66met polymorphism affects human memory-related hippocampal activity and predicts memory performance
    Ahmad R Hariri
    Clinical Brain Disorders Branch, Intramural Research Program, National Institute of Mental Health, National Institutes of Health, United States Department of Health and Human Services, Bethesda, Maryland 20892 1384, USA
    J Neurosci 23:6690-4. 2003
    ..These data implicate a specific genetic mechanism for substantial normal variation in human declarative memory and suggest that the basic effects of BDNF signaling on hippocampal function in experimental animals are important in humans...
  36. ncbi request reprint Interindividual differences in functional interactions among prefrontal, parietal and parahippocampal regions during working memory
    Michael F Glabus
    Unit on Integrative Neuroimaging, National Institutes of Health, Department of Health and Human Services, 9000 Rockville Pike, Bethesda, MD, 20892 1365, USA
    Cereb Cortex 13:1352-61. 2003
    ..These results demonstrate that individual behavioral characteristics are reflected in specific neurofunctional patterns at the system level and that these can be captured by analytical techniques such as SEM...
  37. ncbi request reprint Brain imaging as an approach to phenotype characterization for genetic studies of schizophrenia
    Joseph H Callicott
    Clinical Brain Disorders Branch, NIMH NIH, Bethesda, MD, USA
    Methods Mol Med 77:227-47. 2003
  38. ncbi request reprint Functional lateralization of the sensorimotor cortex in patients with schizophrenia: effects of treatment with olanzapine
    Alessandro Bertolino
    Psychiatric Neuroscience Group, Section on Mental Disorders, Department of Psychiatric and Neurological Sciences, University of Bari, Bari, Italy
    Biol Psychiatry 56:190-7. 2004
    ..The objective of the present longitudinal study was to evaluate whether such cortical abnormalities represent state or trait phenomena of the disorder...
  39. pmc Variation in GRM3 affects cognition, prefrontal glutamate, and risk for schizophrenia
    Michael F Egan
    Clinical Brain Disorders Branch, Intramural Research Program, National Institute of Mental Health NIH DHHS, Building 10, Center Drive, Bethesda, MD 20892, USA
    Proc Natl Acad Sci U S A 101:12604-9. 2004
    ..These convergent data point to a specific molecular pathway by which GRM3 genotype alters glutamate neurotransmission, prefrontal and hippocampal physiology and cognition, and thereby increased risk for schizophrenia...
  40. ncbi request reprint The G72/G30 gene complex and cognitive abnormalities in schizophrenia
    Terry E Goldberg
    Clinical Brain Disorders Branch, IRP, NIMH, NIH, Bethesda, MD, USA
    Neuropsychopharmacology 31:2022-32. 2006
    ..We present evidence that SNP variations in the G72 gene region increase risk of cognitive impairment in schizophrenia. SNP variations were not strongly associated with clinical diagnosis in family-based analyses...
  41. ncbi request reprint Brain regions underlying response inhibition and interference monitoring and suppression
    Giuseppe Blasi
    CBDB, GCAP, National Institute of Mental Health, National Institutes of Health, Department of Health and Human Services, Building 10, Center Drive, Bethesda, MD 20982 1379, USA
    Eur J Neurosci 23:1658-64. 2006
    ..These results extend previous findings by suggesting regional functional specialization within a cortical network supporting cognitive control...
  42. ncbi request reprint Neurophysiological correlates of age-related changes in working memory capacity
    Venkata S Mattay
    Clinical Brain Disorders Branch, Genes, Cognition and Psychosis Program, National Institute of Mental Health, National Institutes of Health, 9000 Rockville Pike, Bethesda, MD 20892, USA
    Neurosci Lett 392:32-7. 2006
    ..As cognitive demand increases, however, they are pushed past a threshold beyond which physiological compensation cannot be made and, a decline in performance occurs...
  43. ncbi request reprint Dissociating the effects of Sternberg working memory demands in prefrontal cortex
    Mario Altamura
    Department of Biomedical Sciences, Psychiatry Unit, University of Foggia, Italy
    Psychiatry Res 154:103-14. 2007
    ..These results suggest the possibility that top-down modulation of attention or cognitive control at encoding and/or decisionmaking may be mediated by these areas...
  44. ncbi request reprint Cortical systems associated with covert music rehearsal
    Frederick J P Langheim
    Clinical Brain Disorders Branch, IRP, NIMH, NIH, Bethesda, Maryland 20892, USA
    Neuroimage 16:901-8. 2002
    ..These data implicate an associative network independent of primary sensorimotor and auditory activity, likely representing the cortical elements most intimately linked to music production...
  45. ncbi request reprint Effect of catechol-O-methyltransferase val158met genotype on attentional control
    Giuseppe Blasi
    Clinical Brain Disorders Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland 20892 1379, USA
    J Neurosci 25:5038-45. 2005
    ..These results indicate that met allele load and presumably enhanced dopaminergic tone improve the "efficiency" of local circuit processing within the cingulate cortex and thereby its function during AC...
  46. ncbi request reprint The brain-derived neurotrophic factor val66met polymorphism and variation in human cortical morphology
    Lukas Pezawas
    Genes, Cognition, and Psychosis Program, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland 20892 1379, USA
    J Neurosci 24:10099-102. 2004
    ....
  47. ncbi request reprint Interaction of COMT (Val(108/158)Met) genotype and olanzapine treatment on prefrontal cortical function in patients with schizophrenia
    Alessandro Bertolino
    Dipartimento di Scienze Neurologiche e Psichiatriche, Universita degli Studi di Bari, Piazza Giulio Cesare 9, 70124, Bari, Italy
    Am J Psychiatry 161:1798-805. 2004
    ....
  48. doi request reprint False positives in imaging genetics
    Andreas Meyer-Lindenberg
    Unit for Systems Neuroscience in Psychiatry, National Institute for Mental Health, NIH, DHHS, 9000 Rockville Pike, Bethesda, MD 20892 1365, USA
    Neuroimage 40:655-61. 2008
    ..In fact, our observations indicate that these statistical thresholds are conservative...