Differential effects of depressive symptoms on prospective and retrospective memory in old age

Rumination, but not mood, predicts prospective memory performance: novel insights from a derived measure of trait rumination

Prospective memory (PM) is the accurate execution of an intention in the future. PM may be negatively impacted by negative affect, but the underlying mechanisms remain unclear. Rumination may increase the frequency of task-irrelevant thoughts, which deplete attentional capacity and reduce performance. To date, no studies have examined state and trait rumination on an online measure of PM. The present study examined the effects of state and trait rumination on an event-based, focal PM task embedded within a one-back task over multiple sessions. 95 non-depressed adults (18-53 years) completed measures of state/trait rumination, mood, and PM on at least two occasions. Using multi-level modelling, we found that a derived measure of trait rumination, but not an established trait rumination survey, nor negative mood, predicted poorer PM accuracy. These novel findings demonstrate that trait rumination may partially underlie the association between negative affect & PM in a non-clinical sample, and highlight the potential of online methods to study PM.

Prospective memory, retrospective memory, and individual differences in cognitive abilities, personality, and psychopathology

Although individual differences in processing speed, working memory, intelligence, and other cognitive functions were found to explain individual differences in retrospective memory (RetM), much less is known about their relationship with prospective memory (ProM). Moreover, the studies that investigated the relationship between ProM and cognitive functions arrived to contradictory conclusions. The relationship between ProM, personality, and psychopathology is similarly unsettled. Meta-analytic reviews of the relationships of ProM with aging and personality suggest that the contradictory findings may be due to widespread methodological problems plaguing ProM research including the prevalent use of inefficient, unreliable binary measures; widespread ceiling effects; failure to distinguish between various ProM subdomains (e.g., episodic ProM versus vigilance/monitoring); various confounds; and, importantly, small sample sizes, resulting in insufficient statistical power. Accordingly, in a large scale study with nearly 1,200 participants, we investigated the relationship between episodic event-cued ProM, episodic RetM, and fundamental cognitive functions including intelligence, personality, and psychopathology, using reliable continuous measures of episodic event-cued ProM. Our findings show that (a) continuous measures of episodic event-cued ProM were much more reliable than binary measures, (b) episodic event-cued ProM was associated with measures of processing speed, working memory, crystallized and fluid intelligence, as well as RetM, and that such associations were similar for ProM and RetM, (c) personality factors did not improve prediction of neither ProM nor RetM beyond the variance predicted by cognitive ability, (d) symptoms of psychopathology did not improve the prediction of ProM although they slightly improved the prediction of RetM, and (e) participants' sex was not associated with ProM but showed small correlations with RetM. In addition to advancing our theoretical understanding of ProM, our findings highlight the need to avoid common pitfalls plaguing ProM research.

Is prospective memory related to depression and anxiety? A hierarchical MPT modelling approach

Prospective memory (PM) refers to remembering to perform an action in the future. One hundred and twenty-nine students completed a laboratory event-based PM task as well as depression and anxiety questionnaires. The data were analysed with the beta-MPT version of the multinomial processing tree model of event-based PM. Thereby, the prospective and retrospective components of PM were estimated for each participant and were then correlated with depression and anxiety. State anxiety was negatively correlated with the prospective component of PM. Neither depression nor trait anxiety were related to either component of PM.

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

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.

Prospective memory deficits in patients with bipolar disorder: a preliminary study

Prospective memory (PM) is the ability to remember to do something in the future without explicit prompts. To date, little has been known about PM deficits in bipolar disorder (BD). This study examined the nature and correlates of PM in patients with BD. Forty clinically stable BD patients and 40 matched healthy controls formed the study sample. Socio-demographic characteristics, PM, psychosocial functioning, retrospective memory (RM), and IQ were measured in all participants, whereas clinical condition was measured in patients with standardized assessment instruments. Patients performed significantly more poorly on the time-based PM task than controls (10.6 ± 5.0 vs. 14.6 ± 3.0, p < .001). In correlation analyses, older age, lower education, more severe depressive and manic symptoms, poor psychosocial functioning, poor RM, and lower scores in IQ were significantly associated with poor performance in the time-based PM task, whereas poor RM and lower scores in IQ associated with poorer performance in the event-based PM task in patients. In multivariate analyses, severity of depression and older age significantly contributed to poor performance in the time-based PM task, whereas poor RM contributed to poor performance in the event-based PM task in patients. The time-based PM is impaired in BD patients. Depressive symptoms, age, and RM were determinants of certain aspects of impaired PM performance in BD patients.

Thyroid stimulating hormone and prospective memory functioning in old age

Alterations of thyroid functioning are common in old age. Even among persons free from thyroid disorders, subclinical variations in thyroid functioning may affect cognitive performance. However, it is unknown whether prospective memory (ProM) is related to thyroid stimulating hormone (TSH) variations. An association could be expected, as changes in the thyroid gland have been linked to alterations in frontal brain regions that play a key role in prospective remembering. Thus, the aim of this study was to examine whether subclinical variations in thyroid functioning affect ProM performance. We studied 103 participants, 75 years and older, who were free from thyroid disorders and had serum levels of TSH and thyroxine (T4) within normal ranges. Interestingly, we found a non-linear association between TSH and ProM performance, where persons with TSH levels above the fourth quartile performed substantially better than persons in the other quartiles. T4 levels were unrelated to ProM performance. This pattern suggests that the previously identified "normal-range" interval for TSH should be moved further up in old age, at least when cognitive functioning is considered.