Neuropsychological deficits in tests of executive function in asymptomatic and symptomatic HIV-1 seropositive men

Abstract

SynopsisThere has been much debate about the exact nature and time of onset of the cognitive impairments associated with infection by the human immunodeficiency virus type 1 (HIV-1). Studies to date have not reached consistent conclusions. The present study comprised 22 asymptomatic and 18 symptomatic HIV-1 seropositive men, whose only risk factor for contraction of the virus was sexual intercourse, and 18 seronegative controls matched for age and IQ. Subjects were given computerized neuropsychological tests from the CANTAB battery, which assessed visuospatial memory, attention and executive function. Both the asymptomatic and the symptomatic HIV-1 seropositive subjects showed a selective pattern of deficits relative to the controls. In addition, the seropositive subjects were subtly but significantly impaired on tests of executive function but unimpaired on certain tests of visual memory. This finding supports an hypothesis that frontostriatal dysfunction occurs in HIV-1 infected individuals prior even to the expression of clinical symptoms.

Microglia-passaged simian immunodeficiency virus induces neurophysiological abnormalities in monkeys

“…One advantage of the Cambridge Neuropsychological Test Automated Battery is that data collected in monkeys can be directly compared with data collected in human patients. A study of HIV-infected patients (symptomatic and asymptomatic) tested using this battery (26) revealed impairments in the ability to shift attentional set similar to that observed in the monkeys after SIV infection. These results reflect an inability to redirect attention toward a dimension of the stimuli that was previously uncorrelated with reward and that has been shown to involve frontal lobe function (27,30).…”

“…Three of four infected monkeys were trained on a computerized test battery (Cambridge Neuropsychological Test Automated Battery, Paul Fray, United Kingdom) adapted for use with monkeys from a similar battery that has been used to test HIV ϩ patient populations (26). Baseline data were collected before inoculation with SIV-infected microglia.…”

Cognitive complaints, depression, medical symptoms, and their association with neuropsychological functioning in HIV infection: A structural equation model analysis.

“…Consequently, standard neuropsychological tests may not be sensitive enough to detect the subtle neuropsychological deficits present in the early stages of the disease (Sahakian et al, 1995). Subjective cognitive complaints may include decreased attention and concentration, forgetfulness, difficulty completing more than one task simultaneously, and slowed thinking (Gibbs, Andrewes, Szmukler, Mulhall, & Bowden, 1990;Hinkin et al, 1998;Maj et al, 1994;Mehta et al, 1996).…”

Callosal Compromise Differentially Affects Conflict Processing and Attentional Allocation in Alcoholism, HIV, and Their Comorbidity

“…Chronic alcoholism adversely disrupts executive control mechanisms relying on prefrontal and parietal attentional brain systems (Nixon et al 1988;Sullivan et al 2000;Tapert et al 2001). Lack of executive function control over attentional systems has also been reported in patients infected with human immunodeficiency virus (HIV) (Chao et al 2004;Hinkin et al 1999;McArthur 2004;Sahakian et al 1995).…”

“…Chronic alcoholism adversely disrupts executive control mechanisms relying on prefrontal and parietal attentional brain systems (Nixon et al 1988;Sullivan et al 2000;Tapert et al 2001). Lack of executive function control over attentional systems has also been reported in patients infected with human immunodeficiency virus (HIV) (Chao et al 2004;Hinkin et al 1999;McArthur 2004;Sahakian et al 1995).The Stroop Color Word Test (Stroop 1935) is a widely used paradigm to study selective attentional processes that require conflict resolution and response inhibition between competing stimulus attributes (Bush et al 2003;Carter et al 1999;Fan et al 2003;MacDonald et al 2000;Salo et al 2001). The Stroop phenomenon describes slower responses when subjects are asked to name the ink color of a word printed in a color incongruent with the word's meaning (e.g., the word "red" written in blue ink) relative to when the word's meaning and ink color are the same (e.g., the word "red" written in red ink).…”