title: Differences in startle reflex and prepulse inhibition in European-Americans and African-Americans.
abstract: The acoustic startle reflex and its modulation by a prepulse are psychophysiological phenomena that are commonly studied to evaluate various aspects of information processing. Recent reports in human populations suggest that subjects from disparate racial backgrounds may have significant differences in the startle response. To determine if this pattern could be observed in our subject population and whether it extended to prepulse inhibition (PPI), we evaluated baseline startle parameters and PPI in 53 African-Americans (AA) and 38 European-Americans (EA). In AA compared to EA, mean startle magnitude and probability of blink response were lower, with no difference in habituation. PPI was greater in AA than EA when groups were matched on baseline startle magnitude. These findings support the idea of racial differences in startle response. Implications for study design are highlighted, and possible environmental and genetic influences are considered.
authors.affiliation: Atlanta Department of Veterans Affairs Medical Center, Atlanta, Georgia, USA. wendy.hasenkamp@va.gov
authors.forename: Wendy
authors.initials: W
authors.lastname: Hasenkamp
authors.forename: Seth D
authors.initials: SD
authors.lastname: Norrholm
authors.forename: Amanda
authors.initials: A
authors.lastname: Green
authors.forename: Barbara
authors.initials: B
authors.lastname: Lewison
authors.forename: William
authors.initials: W
authors.lastname: Boshoven
authors.forename: Megan
authors.initials: M
authors.lastname: Keyes
authors.forename: Erica
authors.initials: E
authors.lastname: Duncan
mesh_terms: D000161:Acoustic Stimulation; D000328:Adult; D001741:Black or African American; D004576:Electromyography; D005006:Ethnicity / Q000523:psychology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D013216:Reflex, Startle / Q000502:physiology*; D044465:White People