Longer ongoing task delay intervals exacerbate prospective memory deficits in HIV-associated neurocognitive disorders (HAND)

Abstract

The delay interval between encoding a future intention and detection of the retrieval cue is an essential feature of prospective memory (PM). McDaniel and Einstein's (2000) multiprocess theory posits that greater demands are placed on strategic monitoring processes as the delay interval lengthens. This hypothesis was examined in HIV-associated neurocognitive disorders (HAND), which are associated with strategic dyscontrol of PM, likely secondary to prefrontostriatal circuit pathology. Seventy-eight seronegative adults and 49 individuals with HAND comprised the study groups, which were comparable with regard to demographic, psychiatric, and substance use factors. As part of a comprehensive neuropsychological evaluation, participants were administered a well-validated PM measure that included short (2-min) and long (15-min) task delay interval scales that utilized a standardized word search as the ongoing task. Results revealed a significant interaction of group and delay interval, with significant effects of HAND on PM at long, but not short, delay. The long-delay PM effect in HAND was driven primarily by deficits in time-based PM and was most strongly associated with markers of executive dysfunction. In concordance with the multiprocess theory, individuals with HAND were disproportionately vulnerable to PM deficits at longer ongoing task delay intervals, which appear to be driven by strategic dyscontrol of PM that is consistent with the preferential disruption of prefrontal systems in neuroAIDS (neurological complications of AIDS). Difficulty with successfully completing PM tasks following a longer delay could manifest in real-world problems, such as medication nonadherence and unemployment, and characterizing this specific deficit may inform remediation strategies.

Keywords:

• Prospective memory
• HIV/AIDS
• Episodic memory
• Executive functions
• Time perception
• AIDS dementia complex

Acknowledgments

The HIV Neurobehavioral Research Program (HNRP) Group is affiliated with the University of California, San Diego, the Naval Hospital, San Diego, and the Veterans Affairs San Diego Healthcare System, and it includes: Director: Robert Heaton; Co-Directors: J. Hampton Atkinson, Ronald J. Ellis, and J. Allen McCutchan; Center Manager: Thomas D. Marcotte, Jennifer Marquie-Beck, Melanie Sherman; Naval Hospital San Diego: Braden R. Hale (P.I.); Neuromedical Component: Ronald J. Ellis (P.I.), J. Allen McCutchan, Scott Letendre, Edmund Capparelli, Rachel Schrier, Terry Alexander, Debra Rosario, Shannon LeBlanc; Neurobehavioral Component: Robert K. Heaton (P.I.), Mariana Cherner, David J. Moore, Steven Paul Woods, Matthew Dawson; Neuroimaging Component: Terry Jernigan (P.I.), Christine Fennema-Notestine, Sarah L. Archibald, John Hesselink, Jacopo Annese, Michael J. Taylor; Neurobiology Component: Eliezer Masliah (P.I.), Cristian Achim, Ian Everall; Neurovirology Component: Douglas Richman (P.I.), David M. Smith; International Component: J. Allen McCutchan (P.I.); Developmental Component: Cristian Achim, Stuart Lipton (P.I.); Clinical Trials Component: J. Allen McCutchan, J. Hampton Atkinson, Ronald J. Ellis, Scott Letendre; Participant Accrual and Retention Unit: J. Hampton Atkinson (P.I.), Rodney von Jaeger; Data Management Unit: Anthony C. Gamst (P.I.), Clint Cushman (Data Systems Manager); Statistics Unit: Ian Abramson (P.I.), Florin Vaida, Reena Deutsch, Anya Umlauf.

This research was supported by National Institute of Health Grants 2R01MH073419, 1T32DA031098, T32AA013525, and P30MH62512. The views expressed in this article are those of the authors and do not reflect the official policy or position of the Department of the Navy, Department of Defense, or United States Government. The authors thank Marizela Cameron, Nichole A. Duarte, Katie Doyle, and P. Katie Riggs for their help with study management and Sarah Raskin for providing us with the Memory for Intentions Screening Test (MIST).