Kristin E. Flegal

Overthinking skilled motor performance: or why those who teach can't do.

Skilled athletes often maintain that overthinking disrupts performance of their motor skills. Here, we examined whether these experiences have a basis in verbal overshadowing, a phenomenon in which describing memories for ineffable perceptual experiences disrupts later retention. After learning a unique golf-putting task, golfers of low and intermediate skill either described their actions in detail or performed an irrelevant verbal task. They then performed the putting task again. Strikingly, describing their putting experience significantly impaired higher skill golfers’ ability to reachieve the putting criterion, compared with higher skill golfers who performed the irrelevant verbal activity. Verbalization had no such effect, however, for lower skill golfers. These findings establish that the effects of overthinking extend beyond dual-task interference and may sometimes reflect impacts on long-term memory. We propose that these effects are mediated by competition between procedural and declarative memory, as suggested by recent work in cognitive neuroscience.

Everyday Memory Errors in Older Adults

ABSTRACT Despite concern about cognitive decline in old age, few studies document the types and frequency of memory errors older adults make in everyday life. In the present study, 105 healthy older adults completed the Everyday Memory Questionnaire (EMQ; Sunderland, Harris, & Baddeley, 1983, Journal of Verbal Learning and Verbal Behavior, 22, 341), indicating what memory errors they had experienced in the last 24 hours, the Memory Self-Efficacy Questionnaire (MSEQ; West, Thorn, & Bagwell, 2003, Psychology and Aging, 18, 111), and other neuropsychological and cognitive tasks. EMQ and MSEQ scores were unrelated and made separate contributions to variance on the Mini Mental State Exam (MMSE; Folstein, Folstein, & McHugh, 1975, Journal of Psychiatric Research, 12, 189), suggesting separate constructs. Tip-of-the-tongue errors were the most commonly reported, and the EMQ Faces/Places and New Things subscales were most strongly related to MMSE. These findings may help training programs target memory errors commonly experienced by older adults, and suggest which types of memory errors could indicate cognitive declines of clinical concern.

Can Cognitive Training Improve Episodic Memory

Neuroscience-inspired approaches to train cognitive abilities are bringing about a paradigm shift in the way scientists view the treatment of memory dysfunction, but it can be challenging to prove whether such approaches have significant effects.

Memory Distortion in Alzheimer’s Disease: Deficient Monitoring of Short and Long-term Memory

OBJECTIVE This study measured distortions of memory during short-term memory (STM) and long-term memory (LTM) versions of a semantically associated word list learning paradigm. Performance of patients with mild-to-moderate Alzheimers disease (AD; MMSE ≥16) was compared with performance of age-matched, healthy older adult participants. METHOD In a STM version of the Deese-Roediger-McDermott (DRM) task, participants viewed four-word lists and were prompted for recall after a brief interval. The LTM task tested recall memory for 12-word lists. RESULTS Compared with the healthy group, the AD participants show greater impairment on the LTM task than on the STM task, although veridical recall is significantly reduced on both tasks. Furthermore, on both memory tasks, (1) participants with AD generate more nonsemantic intrusions than healthy older adult participants, and (2) semantic intrusion rate, when computed as a proportion of total recall, does not differ between groups. Notably, nonsemantic intrusions are consistently high for AD participants across both STM and LTM despite a marked difference in recall accuracy (65% and 23%, respectively). CONCLUSIONS STM impairment with some preserved semantic processing is evident in AD. The extent and variety of intrusions reported by AD participants indicates a breakdown in their ability to monitor and constrain their recall responses, even within seconds of initial learning.

False Memories Seconds Later: The Rapid and Compelling Onset of Illusory Recognition.

Distortions of long-term memory (LTM) in the converging associates task are thought to arise from semantic associative processes and monitoring failures due to degraded verbatim and/or contextual memory. Sensory-based coding is traditionally considered more prevalent than meaning-based coding in short-term memory (STM), whereas the converse is true of LTM, leading to the expectation that false memory phenomena should be less robust in a canonical STM task. These expectations were violated in 2 experiments in which participants were shown lists of 4 semantically related words and were probed immediately following a filled 3- to 4-s retention interval or approximately 20 min later in a surprise recognition test. Corrected false recognition rates, confidence ratings, and Remember/Know judgments reveal similar false memory effects across STM and LTM conditions. These results indicate that compelling false memory illusions can be rapidly instantiated and that, consistent with unitary models of memory, they originate from processes that are not specific to LTM tasks.

Brain mechanisms of successful recognition through retrieval of semantic context

Episodic memory is associated with the encoding and retrieval of context information and with a subjective sense of reexperiencing past events. The neural correlates of episodic retrieval have been extensively studied using fMRI, leading to the identification of a “general recollection network” including medial temporal, parietal, and prefrontal regions. However, in these studies, it is difficult to disentangle the effects of context retrieval from recollection. In this study, we used fMRI to determine the extent to which the recruitment of regions in the recollection network is contingent on context reinstatement. Participants were scanned during a cued recognition test for target words from encoded sentences. Studied target words were preceded by either a cue word studied in the same sentence (thus congruent with encoding context) or a cue word studied in a different sentence (thus incongruent with encoding context). Converging fMRI results from independently defined ROIs and whole-brain analysis showed regional specificity in the recollection network. Activity in hippocampus and parahippocampal cortex was specifically increased during successful retrieval following congruent context cues, whereas parietal and prefrontal components of the general recollection network were associated with confident retrieval irrespective of contextual congruency. Our findings implicate medial temporal regions in the retrieval of semantic context, contributing to, but dissociable from, recollective experience.

Aging and brain fitness (Commentary on Voelcker-Rehage et al.)

What is bodily fitness and how does it affect brain fitness? Compelling evidence indicates that the two are closely related, especially in older age (Colcombe & Kramer, 2003; Colcombe et al., 2004). Indeed, the cognitive benefits of physical fitness through cardiovascular and strength training have been demonstrated cross-sectionally, longitudinally, and by intervention studies, thereby constituting one of the most reliable messages about successful aging (Kramer & Erickson, 2007; Hertzog et al., 2008; Lustig et al., 2009). Against this encouraging backdrop, Voelcker-Rehage et al. (2010) have made an important set of discoveries that are reported in this issue of EJN. Drawing from animal research, they distinguish between motor fitness (balance, agility, coordination and flexibility) and physical fitness (muscle strength and cardiovascular fitness). They predict that these two forms of fitness will differentially impact both cognitive and neurophysiological functioning in healthy older adults. Their hypothesis is borne out by their behavioral and brain imaging results. Consistent with prior research, performance on executive control tasks was positively related to physical fitness. The novel behavioral result is that motor fitness was associated with both executive control and perceptual speed tasks. This result is important because it specifically links motor fitness to perceptual speed, a processing resource viewed as fundamental to cognitive aging (Salthouse, 1996; Park & Reuter-Lorenz, 2009). Voelcker-Rehage et al. (2010) also collected functional brain imaging data from their older adult sample during a flanker task that places demands on executive control processes, which they analyzed with respect to participants’ fitness. High physical fitness and high motor fitness alike were associated with less activation in frontal regions and parts of temporal and occipital cortex. Voelcker-Rehage et al. (2010) discuss the relationship between increased fitness and decreased task-related activation with reference to the compensation hypothesis (Reuter-Lorenz & Cappell, 2008), which accounts for patterns of greater activation often observed, particularly in frontal regions, in older adults matched for task performance with young adults (Cabeza, 2002). Reduced activation in the brains of high-fit older adults in the present study made them appear ‘younger’ than those of their low-fit peers, independent of the fitness dimension, suggesting that fewer neural resources were needed to perform the task and thus compensatory overactivation was unnecessary. Moreover, different dimensions of fitness had different neural signatures: high physical fitness was selectively associated with activation in frontal and temporal areas engaged by executive control processes, and high motor fitness was selectively associated with activation in parietal areas involved in visuo-spatial processing. As the authors note, these intriguing findings deserve further investigation in a longitudinal training study, joining initial research efforts that have shown cognitive training (Erickson et al., 2007) and cardiovascular training (Colcombe et al., 2004) in older adults can alter activity in brain networks associated with executive control. Future research should pursue crucial follow-up questions. Do both forms of fitness build cognitive reserve, or do they improve neural efficiency whereby there is less dependence on compensatory recruitment? Are both dimensions of fitness equally responsive to interventions? Might motor fitness be more closely related to dedifferentiation of perceptual and motor circuitry than physical fitness because of its link to perceptual speed? The present study contributes significantly to the literature by identifying an understudied dimension of fitnes – motor fitness – that relates to cognitive and neural functioning in older adults. Moreover, an interpretative quandary that often plagues cross-sectional fitness studies – does bodily fitness increase cognitive fitness, or are better agers just better at keeping fit in both mind and body? – is less troublesome for the present study because it identifies two partially dissociable aspects of fitness, and documents their dissociable neurocognitive correlates. The results underscore the complex interactions between brain regions that are inherent to gaining a comprehensive understanding of the effects of age and fitness on functional change. With this report, Voelcker-Rehage et al. (2010) advance the research agenda which has been focused on physical, cardiovascular training, and present an important directive for the design of future interventions to maximize brain fitness in older adults.

You can go your own way: effectiveness of participant-driven versus experimenter-driven processing strategies in memory training and transfer.

ABSTRACT Cognitive training programs that instruct specific strategies frequently show limited transfer. Open-ended approaches can achieve greater transfer, but may fail to benefit many older adults due to age deficits in self-initiated processing. We examined whether a compromise that encourages effort at encoding without an experimenter-prescribed strategy might yield better results. Older adults completed memory training under conditions that either (1) mandated a specific strategy to increase deep, associative encoding, (2) attempted to suppress such encoding by mandating rote rehearsal, or (3) encouraged time and effort toward encoding but allowed for strategy choice. The experimenter-enforced associative encoding strategy succeeded in creating integrated representations of studied items, but training-task progress was related to pre-existing ability. Independent of condition assignment, self-reported deep encoding was associated with positive training and transfer effects, suggesting that the most beneficial outcomes occur when environmental support guiding effort is provided but participants generate their own strategies.

Serial position-dependent false memory effects

ABSTRACT Evidence for false recognition within seconds of encoding suggests that semantic-associative influences are not restricted to long-term memory, consistent with unitary memory accounts but contrary to dual store models. The present study sought further relevant evidence using a modified free recall converging associates task where participants studied 12-item lists composed of 3 semantically distinct quartets (sublists) related to a separate, non-presented theme word (i.e., words 1–4/theme1, 5–8/theme2, and 9–12/theme3). This list construction permits assessment of false recall errors from each sublist, and, particularly, the primacy and recency sublists that have been linked to long- and short-term memory stores. Experiment 1 tested immediate free recall for items. Associative false memories were evident from all sublists, however, significantly less so from the recent sublist, which also showed the highest levels of veridical memory. By inserting a brief (3 s) distractor prior to recall, Experiment 2 selectively reduced veridical memory and increased false memory for the recent sublist while leaving the primacy sublist unaffected. These recall results converge with prior evidence indicating the immediacy of false recognition, and can be understood within a unitary framework where the differential availability of verbatim features and gist-based cues affect memory for primacy and recency sublists.