Part set cuing in older adults: further evidence of intact forgetting in aging

Exploring Inhibitory Control Processes in Highly Superior Autobiographical Memory (HSAM): A Single Case Study

Individuals who possess a Highly Superior Autobiographical Memory (HSAM) can remember their own lives in exceptional detail, retrieving specific autobiographical events in response to dates (e.g., 15th April 1995). The phenomenon remains extremely rare, and little is known about why these individuals can remember substantially more than the general population, without being continually flooded by past memories. According to the cognitive inhibition dependency hypothesis, inhibitory processes modulate general autobiographical memory by determining which memories will (and will not) enter one's consciousness. We hypothesised that these control processes are amplified in HSAM, protecting them from being overwhelmed by their abundance of memories. To explore if cognitive inhibition is exceptional in HSAM, a single case with HSAM (DT) and 20 matched controls completed a battery of 6 tasks assessing various aspects of inhibition (e.g., memory, prepotent motor responses). Participants also completed a screening for obsessive compulsive disorder and autism. Results indicate that DT's inhibitory functioning is comparable to that of the typical population, and thus not exceptional. We conclude that inhibition is unlikely to be the best explanation for extraordinary remembering and add to the growing body of literature that HSAM can occur in the absence of clinical symptomatology. Results are discussed in relation to future directions of HSAM research.

Revisiting the multi-mechanism hypothesis of part-list cuing: the role of list-length and item presentation time

When defining the associative encoding, the multi-mechanism hypothesis of part-list cuing does not heed the effect of list length and item presentation time. Through four experiments, this study first proved that short list length and long item presentation time were the boundary conditions of the part-list cuing effects (Experiment 1). Then, it was further found that under a shorter list length, no matter whether the study context was accessed or not, both the detrimental and beneficial effects of part-list cuing were absent (Experiment 2). While under a longer list length and shorter item presentation time, when access to the study context was maintained, part-list cuing impaired recall and when context access was impaired, part-list cuing facilitated memory retrieval (Experiment 3). Finally, adopting a simplified experimental paradigm, the stability of significant detrimental and beneficial effect in Experiment 3 was further verified (Experiment 4). The findings showed that the effects of part-list cuing have boundary conditions, that is, the impairment and facilitation effect of part-list cuing are constrained by list length and item presentation time, which is a key supplement to the multi-mechanism hypothesis about when the impairment and facilitation effect occurs.

Testing a Strategy-Disruption Account of the List-Strength Effect

Presenting items multiple times on a study list increases their memorability, a process known as item strengthening. The list-strength effect (LSE) refers to the finding that, compared to unstrengthened (pure) lists, lists for which a subset of the items have been strengthened produce enhanced memory for the strengthened items and depressed memory for the unstrengthened items. Although the LSE is found in free recall (Tulving & Hastie, 1972), it does not occur in recognition (Ratcliff et al., 1990). In free recall, the LSE in mixed lists is attributed to a sampling bias promoting priority recall of strong items and consequent output interference affecting weak items. We suggest that, in recognition, the disruption of this pattern through the randomization of test probes is responsible for the null LSE. We present several pilot experiments consistent with this account; however, the registered experiment, which had more statistical power, did not support this account.

Part-List Cues Hinder Familiarity but Not Recollection in Item Recognition: Behavioral and Event-Related Potential Evidence

Participants' memory performance is normally poorer when a subset of previously learned items is provided as retrieval cues than none of the retrieval cues is provided. This phenomenon is called the part-list cuing effect, which has been discovered in numerous behavioral studies. However, there is currently no relevant behavioral or event-related potential (ERP) research to investigate whether the forgetting effect caused by part-list cues is more sensitive to recollection or to familiarity. By combining the part-list cuing paradigm with the Remember/Know procedure, we investigated this issue in the present ERP study. Behavioral data showed part-list cuing induced detrimental effect in two aspects: significantly lowered familiarity of the target items and decreased memory discrimination score (P_r score) for "Know" but not for "Remember" items in the part-list cue condition than in the no-part-list cue condition. ERP data revealed that the FN400 old/new effects, which are associated with familiarity, were absent when providing part-list cues, whereas the late positive complex (LPC) old/new effects, which are associated with recollection, were observed comparably in both part-list cue and no-part-list cue conditions. Converging behavioral and ERP results suggested that part-list cues hindered familiarity-based retrieval but not recollection-based retrieval of item recognition. Theoretical implications of the findings for the part-list cuing effect are discussed.