Examining the effect of cerebral perfusion abnormality magnitude on cognitive performance in recently abstinent chronic cocaine abusers.
OBJECTIVE
Cerebral perfusion abnormalities and neuropsychological impairment are common sequelae of chronic cocaine abuse. While perfusion abnormalities have been shown to relate to cognitive deficits in this substance abuse population, the relationship between cognitive performance and the magnitude of perfusion abnormality has yet to be fully determined.


METHODS
Thirty-seven abstinent cocaine abusers and 13 normal controls were administered resting 99m-Tc-HMPAO single photon emission computed tomography (SPECT) scans followed by a neuropsychological assessment battery tapping executive skills, attention, memory, and motor performance. Statistical parametric mapping (SPM99) techniques were used to analyze the SPECT data to detect significant regional perfusion abnormalities in the cocaine group relative to normal controls, and resulting abnormal SPECT counts were employed for comparison with the assessment measures to examine the relationship between cocaine-induced perfusion abnormalities and cognitive performance.


RESULTS
SPECT data analysis revealed significant regional perfusion abnormalities in the cocaine abuse sample relative to controls and significant differences in neuropsychological functioning on measures of executive functioning, complex attention, memory, and manual dexterity. For chronic cocaine abusers, however, within-group comparisons of the magnitude of abnormal perfusion and neuropsychological performance were largely nonsignificant, with the exception of complex attention and motor speed.


CONCLUSIONS
Perfusion abnormalities and neuropsychological impairments readily distinguished cocaine abusers from normal controls. However, when the magnitude of cocaine-induced perfusion abnormalities is examined in relation to cognitive performance, motor speed and complex attention appear to be the best behaviorial indicants of the severity of perfusion dysfunction within this substance abuse population.
Browndyke
Jeffrey N
JN
Department of Psychiatry and Human Behavior Brown Medical School, Providence, Rhode Island, USA. j.browndyke@duke.edu
Tucker
Karen A
KA
Woods
Steven P
SP
Beauvals
John
J
Cohen
Ronald A
RA
Gottschalk
P C
PC
Kosten
Thomas R
TR
D000293:Adolescent; D000328:Adult; D002540:Cerebral Cortex / Q000098:blood supply* / Q000000981:diagnostic imaging / Q000187:drug effects; D003042:Cocaine / Q000633:toxicity*; D019970:Cocaine-Related Disorders / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000534:rehabilitation; D003072:Cognition Disorders / Q000139:chemically induced* / Q000000981:diagnostic imaging* / Q000503:physiopathology; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D009483:Neuropsychological Tests / Q000706:statistics & numerical data; D011594:Psychometrics / Q000706:statistics & numerical data; D012016:Reference Values; D012039:Regional Blood Flow / Q000187:drug effects / Q000502:physiology; D015203:Reproducibility of Results; D013375:Substance Withdrawal Syndrome / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000534:rehabilitation; D019690:Technetium Tc 99m Exametazime; D015899:Tomography, Emission-Computed, Single-Photon
D019690:Technetium Tc 99m Exametazime; D003042:Cocaine