Studies have found that infection with the Human Immunodeficiency
Virus (HIV) leads to cognitive dysfunction. In fact, attention problems
have been reported to be the most frequent cognitive symptom in
HIV-infected adults. One question is how early in the course of
information processing can attention impairment be detected? To address
this issue, performance on a perceptual span task was examined in 54
HIV-infected adults and 19 seronegative controls. In this task a target
had to be identified in a briefly presented (50 ms) array of 1, 4, or
12 letter-characters. Response accuracy was differentially worse in the
HIV+ group relative to seronegative controls in the most difficult
condition, the 12-item array, but not in the easier conditions. There
was no evidence of a group difference in response strategy due to
disinhibition or in psychomotor speed. These data suggest that HIV
infection leads to a reduction in early visual processing capacity (or
span of apprehension). The present results illustrate a new type of
attentional deficit in HIV and show the impact of HIV on cognition at
an earlier point in information processing than has been previously
reported. (JINS, 2004, 10, 135–140.)