HIV-positive females show blunted neurophysiological responses in an emotion-attention dual task paradigm.

Objective: Although HIV is associated with decreased emotional and cognitive functioning, the mechanisms through which affective changes can alter cognitive processes in HIV-infected individuals are unknown. We aimed to clarify this question through testing the extent to which emotionally negative stimuli prime attention to a subsequent infrequently occurring auditory tone in HIV+ compared to HIV- females.

Methods: Attention to emotional compared to non-emotional pictures was measured via the LPP ERP.

Emotionally negative pictures increase attention to a subsequent auditory stimulus.

Emotionally negative stimuli serve as a mechanism of biological preparedness to enhance attention. We hypothesized that emotionally negative stimuli would also serve as motivational priming to increase attention resources for subsequent stimuli. To that end, we tested 11 participants in a dual sensory modality task, wherein emotionally negative pictures were contrasted with emotionally neutral pictures and each picture was followed 600 ms later by a tone in an auditory oddball paradigm.

ERPs differ from neurometric tests in assessing HIV-associated cognitive deficit.

The onset and time-course of HIV-associated cognitive deficits are not well established. The present experiment compared physiological and neurometric assessments of cognitive decline in HIV-asymptomatic, HIV-symptomatic, and HIV-negative control adult women. The P3 component of standard auditory, event-related electrical potentials of the brain (ERP) and standard neurometric (pencil and paper) test scores were recorded.

An alternative baseline measure for calculation of the mismatch negativity (MMN) component of the event-related potential (ERP).

Mismatch negativity (MMN), a component of the event-related potential, reflects the processing associated with low-probability (deviant) stimuli over and above that required for high-probability (standard) stimuli. Occurring 100-250 ms post stimulus, MMN is evident in the enhanced negativity generated in response to deviant relative to standard stimuli. Traditionally, the MMN waveform is calculated by subtracting the averaged waveform of all standard stimuli from the averaged waveform of all deviant stimuli collected during the same test session.