Brain network activity in monolingual and bilingual older adults

Bilingual older adults typically have better performance on tasks of executive control (EC) than do their monolingual peers, but differences in brain activity due to language experience are not well understood. Based on studies showing a relation between the dynamic range of brain network activity and performance on EC tasks, we hypothesized that life-long bilingual older adults would show increased functional connectivity relative to monolinguals in networks related to EC. We assessed intrinsic functional connectivity and modulation of activity in task vs. fixation periods in two brain networks that are active when EC is engaged, the frontoparietal control network (FPC) and the salience network (SLN). We also examined the default mode network (DMN), which influences behavior through reduced activity during tasks. We found stronger intrinsic functional connectivity in the FPC and DMN in bilinguals than in monolinguals. Although there were no group differences in the modulation of activity across tasks and fixation, bilinguals showed stronger correlations than monolinguals between intrinsic connectivity in the FPC and task-related increases of activity in prefrontal and parietal regions. This bilingual difference in network connectivity suggests that language experience begun in childhood and continued throughout adulthood influences brain networks in ways that may provide benefits in later life

Memory, aging and the brain: Old findings and current issues

In this article I reprise some selected findings and issues from my previous behavioural work on age-related differences in memory, and relate them to current work on the neural correlates of encoding, retrieval and representation. In particular, I describe the case study of a woman who had persistent experiences of erroneous recollection. I also describe the results of a study showing a double dissociation of implicit and explicit memory in younger and older adults. Finally, I assess recent work on loss of specificity in older adults’ encoding and retrieval processes of episodic events. In all cases I attempt to relate these older findings to current ideas and empirical results in the area of memory, aging, and the brain

Donald T. Stuss Obituary, Canadian Psychology

Presents an obituary for Donald T. Stuss (1941–2019). The work of Donald T. Stuss, OC, FRSC, who died in Toronto on September 3, 2019, of complications following pancreatic cancer was world-leading but also notable for his influence on the landscape of Canadian neuroscience. Don worked as a teacher and football coach at high schools in Ontario before returning to the University of Ottawa to pursue graduate studies in psychology; he obtained his PhD in 1976. After a postdoctoral position at the Boston VA Medical Center, Don returned to Ottawa to pursue neuropsychological research at the university and also clinical work at the Ottawa General Hospital, where he served as director of clinical neuropsychological services from 1978 to 1989 and wrote the seminal volume The Frontal Lobes with Frank Benson (Stuss & Benson, 1986). Don had three major research interests in his scientific career: first, the functions of the frontal lobes and their role in cognitive processes, conscious awareness, and feelings of self; second, the effects of traumatic brain injury on these functions; and third, improving clinical approaches to assessment and rehabilitation. Each of these was grounded in Don’s thinking about functions of the frontal lobes in enabling cognitive processes and experiences in the normal adult, as well as how these functions are affected by focal and diffuse damage. Don’s success and influence as a researcher and scientific manager earned him many accolades and prestigious marks of recognition. These included being president of the International Neuropsychological Society, a member of the Order of Ontario, a Fellow of the Royal Society of Canada, and an Officer in the Order of Canada. Donald Stuss was a great neuropsychologist and also a great Canadian. (PsycINFO Database Record (c) 2020 APA, all rights reserved

Age Differences in Predictions and Performance on a Cued Recall Task

The notion that older adults fail to use optimal encoding strategies in memory tasks because of a deficit in memory monitoring was examined in a cued recall task. Participants were given different types of descriptors (initial letters, rhyme, category) for each word during encoding, and these descriptors were later given as cues at recall. Participants also predicted the likelihood of recalling each item. Age differences were found in recall performance, but there were no age differences in average predictions. However, the prediction ratings given by younger adults showed a greater difference between words recalled and words not recalled in the subsequent test than did the ratings of the older adults. Differences in recall associated with different types of processing were predicted poorly by all of the participants, but the relative recallability of specific words was well assessed by both age groups. We concluded that a memory monitoring deficit is not likely to be responsible for age differences in memory

Lexical access in bilinguals: Effects of vocabulary size and executive control

We report the results of two studies investigating lexical access in bilinguals. In Study 1,monolinguals performed better than bilinguals on tests of naming and letter fluency, but not on category fluency. When vocabulary size was considered, most of the effects disappeared or were reduced. In Study 2, a larger group of bilinguals was studied to compare the effect of vocabulary size,and a more restrictive version of the letter fluency task was used to increase executive processing involvement. In this case, bilinguals with matched vocabulary scores outperformed monolinguals on letter fluency, and bilinguals with lower vocabulary scores performed at the same level as monolinguals. The results are discussed in terms of the contributions of vocabulary size and executive control to performance on lexical retrieval tasks

Prospective Memory Is a Key Predictor of Functional Independence in Older Adults

Objectives: Prospective memory (PM), the ability to execute delayed intentions, has received increasing attention in neuropsychology and gerontology. Most of this research is motivated by the claim that PM is critical for maintaining functional independence; yet, there is a dearth of empirical evidence to back up the claims. Thus, the present study tested whether PM predicts functional independence in older adults using validated behavioral performance measures for both PM and functional independence. Methods: Fifty-eight healthy older adults performed a computerized PM paradigm, the Virtual Week task, as well as a timed version of an instrumental activities of daily living (TIADL) task. Furthermore, we assessed vocabulary, processing speed, and self-reported prospective remembering. Results: TIADL scores correlated significantly with performance in the Virtual Week task, vocabulary, and processing speed. Hierarchical linear regressions revealed that vocabulary and Virtual Week performance were significant predictors for TIADL. However, self-reported PM scores did not predict everyday functioning. Conclusions: The findings indicate that PM is an important cognitive ability for successful and independent everyday life beyond vocabulary. Moreover, the results show a substantial incremental contribution of intact PM performance for the prediction of everyday functioning by using objective PM measures. (JINS, 2018, 24, 640–645