Skip to main content
eScholarship
Open Access Publications from the University of California

Scholarly Works (5 results)

  • Thesis
  • Peer Reviewed
UCLA Electronic Theses and Dissertations (2018)

Aging is associated with declines in memory performance and profound functional and structural changes in the brain, though older adult’s ability to selectively learn and retrieve valuable information appears to be well preserved. Prior research suggests that older adults differentially employ elaborative encoding strategies when encoding valuable items and selectively allocate attention to these items, as reviewed in Chapter 1. The underlying aims of the current study were to examine how this selective learning affects different aspects of memory and what cognitive and neural mechanisms may support older adult’s effective learning of valuable information.

Chapter 2 describes findings from a project aimed at determining how value-directed remembering affects different aspects of memory. This research suggests that selectively encoding valuable items is associated with greater recognition performance, higher confidence, and increased recollection in both younger and older adults. Although age-related declines in recollection are typically observed, value’s enhancement of item recollection appears to be intact in healthy aging. Selectively encoding valuable items also resulted in stronger binding between items and incidentally learned task-relevant details, perhaps at the expense of encoding extraneous details. Older adults did not demonstrate greater item-location memory for valuable items, suggesting that value’s influence on associative binding may be diminished in aging.

Chapters 3 and 4 describe two projects designed to investigate how strategic and automatic processes contribute to value-directed remembering, and whether differences in the structural integrity of white matter tracts predicts differences in older adult’s ability to selectively learn based on value. The findings of these two studies suggest that younger adults are relying on a more automatic reward circuit involving the nucleus accumbens and ventral tegmental area, whereas older adults rely on semantic processing in the inferior fronto-occipital fasciculus (IFOF). Older adults may be relying on the IFOF in a compensatory manner. The implications of these findings for theories of aging and learning are discussed in Chapter 5.

    Cover page: Value-Directed Remembering and Aging: Examination of Supporting Mechanisms and Effects on Memory Quality
    • Article
    • Peer Reviewed
    UCLA Previously Published Works (2018)
    Valuable items are often remembered better than items that are less valuable by both older and younger adults, but older adults typically show deficits in binding. Here, we examine whether value affects the quality of recognition memory and the binding of incidental details to valuable items. In Experiment 1, participants learned English words each associated with a point-value they earned for correct recognition with the goal of maximizing their score. In Experiment 2, value was manipulated by presenting items that were either congruent or incongruent with an imagined state of physiological need (e.g., hunger). In Experiment 1, point-value was associated with enhanced recollection in both age groups. Memory for the color associated with the word was in fact reduced for high-value recollected items compared with low-value recollected items, suggesting value selectively enhances binding of task-relevant details. In Experiment 2, memory for learned images was enhanced by value in both age groups. However, value differentially enhanced binding of an imagined context to the item in younger and older adults, with a strong trend for increased binding in younger adults only. These findings suggest that value enhances episodic encoding in both older and younger adults but that binding of associated details may be reduced for valuable items compared to less valuable items, particularly in older adults. (PsycINFO Database Record
      Cover page: The Effects of Value on Context-Item Associative Memory in Younger and Older Adults
      • Article
      • Peer Reviewed
      UCLA Previously Published Works (2017)
      We examined the effects of value on recognition by assessing its contribution to recollection and familiarity. In three experiments, participants studied English words, each associated with a point-value they would earn for correct recognition, with the goal of maximizing their score. In Experiment 1, participants provided Remember/Know judgments. In Experiment 2 participants indicated whether items were recollected or if not, their degree of familiarity along a 6-point scale. In Experiment 3, recognition of words was accompanied by a test of memory for incidental details. Across all experiments, participants were more likely to recognize items with higher point-value. Furthermore, value appeared to primarily enhance recollection, as effects on familiarity were small and not consistent across experiments. Recollection of high-value items appears to be accompanied by fewer incidental details, suggesting that value increases focus on items at the expense of irrelevant information.
        Cover page: Recognizing What Matters: Value Improves Recognition by Selectively Enhancing Recollection.
        • Article
        • Peer Reviewed
        UCLA Previously Published Works (2019)
        White matter microstructure changes substantially in aging. To better understand how the integrity of white matter structures supports the selective learning of rewarding material, 23 healthy older adults were tested on a value-directed remembering task. This task involved successive free recall word lists where items differed in importance, as denoted by value cues preceding each word. White matter structure was measured using diffusion tensor imaging (DTI). We found that greater structural integrity (as measured by lower mean diffusivity) in left inferior fronto-occipital fasciculus was associated with greater recall for high-value items, but not low-value items. Older adults with greater structural integrity in a tract involved in semantic processing are thus able to more successfully encode high-value items for subsequent recall. However, unlike prior findings in younger adults, older adults' memory for high value-items was not significantly correlated with the structural integrity of the uncinate fasciculus, nor with the strength of anatomical connectedness between the bilateral nucleus accumbens to ventral tegmental area reward pathway. These structural imaging findings add support to recent functional neuroimaging demonstrations that value-related modulation of memory in older adults depends heavily on brain circuits implicated in controlled processing of semantic knowledge.
          Cover page: White matter integrity in brain structures supporting semantic processing is associated with value-directed remembering in older adults
          • Article
          • Peer Reviewed
          UCLA Previously Published Works (2019)
            Cover page: Forget me not: Encoding processes in value-directed remembering
            Top