Memory and aging

Today, we’re looking at two very different studies of memory in the aging. First, Noël & Picard (2025) “Why Humor’s Positive Effect on Memory Disappears with Aging” in Emotion. Here’s the edited abstract:

Numerous studies have highlighted the beneficial effect of humor on memory in younger adults. While older adults are known to preferentially process positive information and appreciate humor, no study has investigated whether the effect of humor on memory persists in aging. Two studies were conducted to address this gap. In Study 1, 19 younger adults and 20 older adults performed a memory task designed to compare the recall of humorous and neutral photograph sequences. Results revealed the typical beneficial effect of humor on free recall in young adults, while in older adults, humor had no influence on free recall and even a detrimental effect in the cued recall task, suggesting that humor primarily affects encoding processes. Study 2 aimed to replicate these findings and further investigate the mechanisms underlying this negative effect in older adults (i.e., the effect of humor per se or confounding incongruity effect). To this end, 37 younger adults and 38 older adults completed a similar task, now featuring three different photograph sequences (humorous, incongruous and neutral). Older adults exhibited no further effect of humor on memory when incongruity was controlled, whereas younger adults continued to recall humorous photographs better than neutral ones, in the two retrieval conditions. As expected, older adults also showed a negative effect of incongruity on memory, consistent with the inefficiency of their binding processes. Taken together, these studies show that the positive effect of humor on memory disappears in aging, owing to the inherent incongruity of humorous stimuli, combined with an associative memory deficit. 

I liked this one because I’m one of those people who was sure humor aided memory. The finding that humor actually had a detrimental effect on cued recall is helpful. I especially liked the idea that it is encoding that is affected by humor and the combination of incongruity and encoding deficits that is at play. Since Noël & Picard reference memory binding, the next study may also be helpful. Aghamoosa, Rbeiz, Horn, Thorn & Benitez (2024) published “The Memory Binding Test in a Longitudinal Study of Cognitive Aging and Preclinical Disease” in Neuropsychology. Here are the edited abstract and impact statement:

The Memory Binding Test (MBT) shows promise in detecting early cognitive changes associated with Alzheimer’s disease (AD). This study assesses the psychometric properties (i.e., construct and criterion validity, test–retest reliability) of the MBT and its sensitivity to incipient disease and incident cognitive impairment. One hundred forty-nine cognitively unimpaired adults ages 45–85 completed the MBT and neuropsychological tests at baseline; 132 returned for 2-year follow-up. Based on neuroradiological ratings of amyloid positron emission tomography and MRI markers at baseline, they were categorized as healthy (n = 94) or having preclinical disease (n = 55, either on the AD continuum or having non-AD pathologic change). Construct validity was assessed by the associations between MBT scores, demographics, and neuropsychological scores within the healthy group. Criterion validity was assessed by testing how MBT scores correlate with AD biomarkers, differ and discriminate between groups at baseline, and predict incident cognitive impairment. MBT scores decreased with age and were strongly associated with memory and global cognition. MBT scores were largely not associated with amyloid, hippocampal volume, or AD signature cortical volume but related to white matter lesion volume in those with preclinical disease. The preclinical groups performed worse on MBT immediate free recall at baseline than the healthy group, but no scores predicted incident cognitive impairment at follow-up. Most scores demonstrated modest test–retest reliability. This study demonstrates that the MBT has adequate construct validity in cognitively unimpaired adults, moderate sensitivity to preclinical disease cross-sectionally, and limited prognostic utility. Careful consideration of demographic influences on score interpretation remains necessary.

The MBT is sensitive to early disease-related deficits in associative memory cross-sectionally despite being highly confounded by demographic factors, particularly age. Performance on the MBT at baseline did not predict incident MCI over 2 years. Although the MBT may be useful for detecting subtle cognitive deficits in individuals with biomarker evidence of preclinical disease, the MBT may be less useful for predicting who will progress to MCI in the near future. Future work should test the generality of these findings using larger and more diverse samples, including additional biomarkers (e.g., tau), and comparing the relative merits of the MBT to other measures that are sensitive to cognitive change in preclinical disease. Additionally, the development of age-adjusted norms for the MBT may be warranted. 

I thought this work was helpful in providing an instrument to healthy and pre-clinical seniors. Although it can’t predict the course of mild cognitive impairment, it may be useful in identifying early disease-related deficits.