Event-based prospective memory deficits in individuals with high depressive symptomatology: Problems controlling attentional resources?

Abstract

Depression has been found to be related to neurocognitive deficits in areas important to successful prospective memory (PM) performance, including executive function, attention, and retrospective memory. However, research specific to depression and PM has produced a mixed pattern of results. The current study further examined the task conditions in which event-based PM deficits may emerge in individuals with high depressive symptomatology (HDS) relative to individuals with low depressive symptomatology (LDS) and the capacity of HDS individuals to allocate attentional resources to event-based PM tasks. Sixty-four participants (32 HDS, 32 LDS) were required to make a PM response when target words were presented during an ongoing lexical decision task. When the importance of the ongoing task was emphasized, response time costs to the ongoing task, and PM accuracy, did not differ between the HDS and LDS groups. This finding is consistent with previous research demonstrating that event-based PM task accuracy is not always impaired by depression, even when the PM task is resource demanding. When the importance of the PM task was emphasized, costs to the ongoing task further increased for both groups, indicating an increased allocation of attentional resources to the PM task. Crucially, while a corresponding improvement in PM accuracy was observed in the LDS group when the importance of the PM task was emphasized, this was not true for the HDS group. The lack of improved PM accuracy in the HDS group compared with the LDS group despite evidence of increased cognitive resources allocated to PM tasks may have been due to inefficiency in the application of the allocated attention, a dimension likely related to executive function difficulties in depression. Qualitatively different resource allocation patterns may underlie PM monitoring in HDS versus LDS individuals.

Keywords:

• Event-based prospective memory
• Depression
• Attentional resource allocation
• Prospective memory importance
• Prospective memory costs

Acknowledgements

We wish to thank Gillian Yeo with her assistance in conducting the multilevel modelling. We acknowledge that the information in this manuscript and the manuscript itself have never been published either electronically or in print. The authors have no conflicts of interest to declare.

Funding

This research received no specific grant from any funding agency, or commercial or not-for-profit organization. We do not have any financial interests or benefits arising from the direct application of this research.

Notes

¹ Although it was not ideal that our prescreening in each semester was based on different instruments, the prescreening purpose was to simply identify individuals with extreme levels of depression. Since DASS and BDI scores are highly correlated (Osman et al., 1997), there is not likely to have been any substantial impact of using the different instruments across two semesters.