Neuropsychological Practice Effects in the Context of Cognitive Decline: Contributions from Learning and Task Novelty

Abstract

Although cognitive decline is typically associated with decreasing practice effects (PEs) (presumably due to declining memory), some studies show increased PEs with declines in cognition. One explanation for these inconsistencies is that PEs reflect not only memory, but also rebounds from adapting to task novelty (i.e., novelty effect), leading to increased PEs. We examined a theoretical model of relationships among novelty effects, memory, cognitive decline, and within-session PEs. Sixty-six older adults ranging from normal to severely impaired completed measures of memory, novelty effects, and two trials each of Wechsler Adult Intelligence Scale, 4 th Edition Symbol Search and Coding. Interrelationships among variables were examined using regression analyses. PEs for Symbol Search and Coding (a) were related to different proposed PE components (i.e., memory and novelty effects), such that novelty effect predicted Symbol Search PE (R2 =.239, p<.001) and memory predicted Coding PE (R2 =.089, p=.015), and (b) showed different patterns across stages of cognitive decline, such that the greatest cognitive decline was associated with smallest Coding PE (R2 =.125, p=.004), whereas intermediate cognitive decline was associated with the greatest Symbol Search PE (R2 =.097, p=.040). The relationship between cognitive decline and PE for Symbol Search was partially mediated by novelty effect among older adults with abnormal cognitive decline (model R2 =.286, p<.001). These findings (a) suggest that PE is not a unitary construct, (b) offer an explanation for contradictory findings in the literature, and (c) highlight the need for a better understanding of component processes of PE across different neuropsychological measures.

Retest effects in working memory capacity tests: A meta-analysis

“…For both task paradigms, it seems reasonable to assume that alternate test forms were constructed using the same set of stimuli (e.g., digits, letters, or dot locations in a matrix), but varying their composition and order. Moreover, it has been suggested that the development of test-taking strategies and the accommodation to novel task demands plays a larger role than memory effects in complex tasks (Basso, Bornstein, & Lang, 1999;Beglinger et al, 2005;Thorgusen, Suchy, Chelune, & Baucom, 2016), and both N-back tasks and complex span tasks can be regarded as attentionally demanding. Note, however, that in a lot of studies it was not reported whether identical or alternate test forms were used.…”

Deleterious Impact of Expressive Suppression on Test Performance Persists at One-Year Follow-Up in Community-Dwelling Older Adults

“…Given that memory and learning have been shown to predict the magnitude of practice effects on at least some neuropsychological measures (Busch, Chelune, & Suchy, 2005;Thorgusen, Suchy, Chelune, & Baucom, 2016), the above findings suggest that ES may also result in a reduced ability to benefit from task exposure or task practice. While the indirect evidence supporting this idea is compelling, the current literature is limited in several ways.…”

The long arm of childhood socioeconomic deprivation on mid- to later-life cognitive trajectories: A cross-cohort analysis

“…As they familiarise themselves with the task characteristics, they then exhibit a “rebound” in their performance (i.e., a “novelty effect) [36, 37]. Thorgusen and colleagues [38] demonstrated that both memory and novelty effects uniquely contribute towards these neuropsychological practice effects, and cognitive impairment is more likely to be associated with smaller practice effects in memory tasks, but larger practice effects in tasks assessing other cognitive domains. It has been proposed that such novelty effect may be a useful early marker of declining cognitive reserve and neurodegeneration, but more research is required to understand how practice effects differ depending on the population, task complexity, and cognitive domain assessed before conclusions can be drawn about their potential diagnostic and prognostic utility.…”