Sensorimotor gating deficits in adults with autism.
BACKGROUND
Prepulse inhibition (PPI) is an operational measure of sensorimotor gating and is impaired in a family of neuropsychiatric disorders characterized by abnormalities of inhibitory function. Adults with autistic disorder (AD) exhibit clinical features of inhibitory deficits, such as restrictive and repetitive behaviors, that may be explained by deficits in sensorimotor gating.


METHODS
Acoustic startle reactivity, habituation, and PPI (30-, 60-, 120-msec interstimulus intervals) were assessed in 14 adult men diagnosed with AD and 16 typically developing normal comparison (NC) participants. All participants were administered measures of intelligence and frontal-executive functioning.


RESULTS
Adults with AD exhibited significantly less PPI in the 60-msec condition than NC participants, which was correlated with increased ratings of restricted and repetitive behaviors. The groups did not differ on measures of startle amplitude or overall habituation. There was, however, a significant group-by-block habituation effect. Furthermore, PPI was not related to intelligence but was moderately associated with performance on a measure of frontal-executive functioning.


CONCLUSIONS
Adults with AD have sensorimotor gating deficits similar to other neurodevelopmental disorders, implicating a failure of normal inhibitory regulation of sensory, motor, and attentional mechanisms. Thus, PPI deficits may be indirectly linked to one of the hallmark features of AD.
Perry
William
W
Department of Psychiatry, University of California, San Diego, California, USA. wperry@ucsd.edu
Minassian
Arpi
A
Lopez
Brian
B
Maron
Leeza
L
Lincoln
Alan
A
D000161:Acoustic Stimulation / Q000379:methods; D000328:Adult; D001321:Autistic Disorder / Q000150:complications*; D020233:Gait Disorders, Neurologic / Q000209:etiology*; D006185:Habituation, Psychophysiologic; D006801:Humans; D007266:Inhibition, Psychological; D007360:Intelligence; D008297:Male; D011340:Problem Solving / Q000502:physiology; D011569:Psychiatric Status Rating Scales; D013216:Reflex, Startle / Q000502:physiology*; D013997:Time Factors