Strategic grouping in the spatial span memory task

Spatial short-term memory performance was examined in relation to participants’ strategies. A total of 20 adult participants viewed and reproduced sequences of locations that varied in length (five, six, seven, or eight locations) and spatial separability (a manipulation of the configurations). In trial-by-trial self-reports, participants described five types of strategies. Chunking the spatial sequences into groups of three or four locations was the sole strategy associated with increased accuracy. Participants demonstrated considerable variability in the strategies that they selected, suggesting that cognitive resources are allocated to strategy selection, execution, and monitoring in the spatial span task. Spatially separable sequences were more accurately recalled than nonseparable sequences, independent of strategic grouping, suggesting two levels of grouping in the spatial span task.     

The role of working memory capacity in autobiographical retrieval: Individual differences in strategic search

Remembering previous experiences from one's personal past is a principal component of psychological well-being, personality, sense of self, decision making, and planning for the future. In the current study the ability to search for autobiographical information in memory was examined by having college students recall their Facebook friends. Individual differences in working memory capacity manifested itself in the search of autobiographical memory by way of the total number of friends remembered, the number of clusters of friends, size of clusters, and the speed with which participants could output their friends' names. Although working memory capacity was related to the ability to search autobiographical memory, participants did not differ in the manner in which they approached the search and used contextual cues to help query their memories. These results corroborate recent theorising, which suggests that working memory is a necessary component of self-generating contextual cues to strategically search memory for autobiographical information.     

Keeping an eye on the truth? Pupil size changes associated with recognition memory

During recognition memory tests participants' pupils dilate more when they view old items compared to novel items. We sought to replicate this “pupil old/new effect” and to determine its relationship to participants' responses. We compared changes in pupil size during recognition when participants were given standard recognition memory instructions, instructions to feign amnesia, and instructions to report all items as new. Participants' pupils dilated more to old items compared to new items under all three instruction conditions. This finding suggests that the increase in pupil size that occurs when participants encounter previously studied items is not under conscious control. Given that pupil size can be reliably and simply measured, the pupil old/new effect may have potential in clinical settings as a means for determining whether patients are feigning memory loss.     

TV or not TV? Does the immediacy of viewing images of a momentous news event affect the quality and stability of flashbulb memories?

The flashbulb accounts of 38 participants concerning the September 11th 2001 terrorist attack reported at both 28 hours and 6 months following the event were examined for quantity, quality, and consistency as a function of the time lapse between first learning of the event and initial viewing of media images. The flashbulb accounts of those who reported seeing images at least an hour after learning of the event differed qualitatively, but not quantitatively, from accounts of participants who reported seeing images at the same time as or within minutes of learning of the event. Delayed viewing of images resulted in less elaborate and generally less consistent accounts across the 6-month interval. The results are discussed in terms of factors affecting flashbulb memory formation and individual differences in connectedness to the event.     

Remembering all that and then some: Recollection of autobiographical memories after a 1-year delay

We have previously shown that repeated retrievals of remote autobiographical memories over the course of one month led to an overall increase in reported detail (Nadel, Campbell, & Ryan, 2007). The current study examined the retrieval of those same memories 1 year later in order to determine whether the level of detail remained stable or whether the memories returned to their original state. Participants reported even more details than they had recalled at least 1 year earlier, including new details that were reported for the first time. This finding was consistent across both multiple and single retrieval conditions, suggesting that the critical factor leading to the increase in recall was the passage of time. These findings provide evidence for long-term effects of repeated retrieval on memory content.     

Alcohol intoxication and memory for events: A snapshot of alcohol myopia in a real-world drinking scenario

Alcohol typically has a detrimental impact on memory across a variety of encoding and retrieval conditions (e.g., Mintzer, 2007; Ray & Bates, 2006). No research has addressed alcohol's effect on memory for lengthy and interactive events and little has tested alcohol's effect on free recall. In this study 94 participants were randomly assigned to alcohol, placebo, or control groups and consumed drinks in a bar-lab setting while interacting with a “bartender”. Immediately afterwards all participants freely recalled the bar interaction. Consistent with alcohol myopia theory, intoxicated participants only differed from placebo and control groups when recalling peripheral information. Expanding on the original hypervigilance hypothesis, placebo participants showed more conservative reporting behaviour than the alcohol or control groups by providing more uncertain and “don't know” responses. Thus, alcohol intoxication had confined effects on memory for events, supporting and extending current theories.     

Psychophysiology of prospective memory

Prospective memory involves the self-initiated retrieval of an intention upon an appropriate retrieval cue. Cue identification can be considered as an orienting reaction and may thus trigger a psychophysiological response. Here we present two experiments in which skin conductance responses (SCRs) elicited by prospective memory cues were compared to SCRs elicited by aversive stimuli to test whether a single prospective memory cue triggers a similar SCR as an aversive stimulus. In Experiment 2 we also assessed whether cue specificity had a differential influence on prospective memory performance and on SCRs. We found that detecting a single prospective memory cue is as likely to elicit a SCR as an aversive stimulus. Missed prospective memory cues also elicited SCRs. On a behavioural level, specific intentions led to better prospective memory performance. However, on a psychophysiological level specificity had no influence. More generally, the results indicate reliable SCRs for prospective memory cues and point to psychophysiological measures as valuable approach, which offers a new way to study one-off prospective memory tasks. Moreover, the findings are consistent with a theory that posits multiple prospective memory retrieval stages.     

The onset of childhood amnesia in childhood: A prospective investigation of the course and determinants of forgetting of early-life events

The present research was an examination of the onset of childhood amnesia and how it relates to maternal narrative style, an important determinant of autobiographical memory development. Children and their mothers discussed unique events when the children were 3 years of age. Different subgroups of children were tested for recall of the events at ages 5, 6, 7, 8, and 9 years. At the later session they were interviewed by an experimenter about the events discussed 2 to 6 years previously with their mothers (early-life events). Children aged 5, 6, and 7 remembered 60% or more of the early-life events. In contrast, children aged 8 and 9 years remembered fewer than 40% of the early-life events. Overall maternal narrative style predicted children's contributions to mother–child conversations at age 3 years; it did not have cross-lagged relations to memory for early-life events at ages 5 to 9 years. Maternal deflections of the conversational turn to the child predicted the amount of information children later reported about the early-life events. The findings have implications for our understanding of the onset of childhood amnesia and the achievement of an adult-like distribution of memories in the school years. They highlight the importance of forgetting processes in explanations of the amnesia.     

Remembered study mode: Support for the distinctiveness account of the production effect

The production effect is the finding that words spoken aloud at study are subsequently remembered better than are words read silently at study. According to the distinctiveness account, aloud words are remembered better because the act of speaking those words aloud is encoded and later recovery of this information can be used to infer that those words were studied. An alternative account (the strength-based account) is that memory strength is simply greater for words read aloud. To discriminate these two accounts, we investigated study mode judgements (i.e., “aloud”/”silent”/”new” ratings): The strength-based account predicts that “aloud” responses should positively correlate with memory strength, whereas the distinctiveness account predicts that accuracy of study mode judgements will be independent of memory strength. Across three experiments, where the strength of some silent words was increased by repetition, study mode was discriminable regardless of strength—even when the strength of aloud and repeated silent items was equivalent. Consistent with the distinctiveness account, we conclude that memory for “aloudness” is independent of memory strength and a likely candidate to explain the production effect.