Diagnostic specificity and neuroanatomical validity of neurological abnormalities in first-episode psychoses.
OBJECTIVE
Neurological abnormalities are frequently seen in patients with first-episode psychotic disorders but are generally considered to be diagnostically nonspecific, neurologically nonlocalizing, and, hence, "soft." This study examined the neuroanatomical correlates and diagnostic specificity of abnormal findings on the neurological examination in first-episode schizophrenia and other psychotic disorders.


METHODS
Neuroleptic-naive patients with schizophrenia (N=90) and with nonschizophrenia psychoses (N=39) and carefully matched healthy subjects (N=93) were compared on total and factor scores for a reliable subset of Neurological Evaluation Scale items. The relationship between neurological examination abnormalities and alterations in the relevant brain structures as assessed by magnetic resonance imaging was examined in a subset of subjects.


RESULTS
Factor scores for repetitive motor task abnormalities were higher in both patient groups, relative to the healthy group, and did not distinguish between the patient groups. Factor scores for abnormalities in cognitively demanding and perceptual tasks were markedly higher in the schizophrenia group, relative to both comparison groups, and were not different between the nonschizophrenia psychoses group and the healthy comparison group. Higher scores for the cognitive/perceptual abnormalities factor were correlated with smaller volumes of the left heteromodal association cortex.


CONCLUSIONS
Neurological signs may serve as expedient bedside measures that are potentially useful in the assessment of idiopathic psychoses, and cognitive/perceptual neurological signs may have a measure of diagnostic specificity. These findings provide neurobiological validation of abnormal findings on the neurological examination. These abnormalities may reflect discrete neuroanatomical alterations in schizophrenia and may have a localizing value.
Keshavan
Matcheri S
MS
Department of Psychiatry, Western Psychiatric Institute and Clinic and University of Pittsburgh School of Medicine, Pittsburg, PA 15213, USA. keshavanms@msx.upmc.edu
Sanders
Richard D
RD
Sweeney
John A
JA
Diwadkar
Vaibhav A
VA
Goldstein
Gerald
G
Pettegrew
Jay W
JW
Schooler
Nina R
NR
D000328:Adult; D001921:Brain / Q000033:anatomy & histology*; D003072:Cognition Disorders / Q000175:diagnosis; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009422:Nervous System Diseases / Q000175:diagnosis*; D009460:Neurologic Examination / Q000706:statistics & numerical data*; D009483:Neuropsychological Tests; D025341:Principal Component Analysis; D011597:Psychomotor Performance / Q000502:physiology; D011618:Psychotic Disorders / Q000175:diagnosis*; D012559:Schizophrenia / Q000175:diagnosis*; D012680:Sensitivity and Specificity