Linda A. Henkel

Evaluating characteristics of false memories: Remember/know judgments and memory characteristics questionnaire compared

Subjects hearing a list of associates to a nonpresented lure word later often claim to have heard the lure (Deese, 1959; Roediger & McDermott, 1995). To examine the characteristics of such false memories, subjects completed a memory characteristics questionnaire (MCQ; Johnson, Foley, Suengas, & Raye, 1988) or made remember/know (RK; Gardiner & Java, 1993) judgments for previously heard theme associates and nonpresented lures. MCQ ratings indicated that false memories for lures had less auditory detail and less remembered feelings and reactions than memories for presented words. In addition, rates of false recognition for lures were significantly lower than rates of correct recognition when items from various themes were intermixed instead of blocked at acquisition and subjects made MCQ ratings instead of RK judgments. This demonstrates that false memories can be affected both by how they are acquired and by how extensively they are examined at retrieval.

Aging and source monitoring: Cognitive processes and neuropsychological correlates

This study shows that relative to younger adults, older adults are more adversely influenced by similar items when judging a memorys source, and the phenomenal features of their correctly and incorrectly attributed memories have greater overlap. The authors argue in accordance with the source monitoring framework that this age-related impairment in source accuracy is related to processes involved in binding features into complex memories and those involved in accessing and evaluating contextual features of memories. These processes are linked to medial temporal and frontal brain regions, respectively, as evidenced by correlations in older adults between source accuracy and neuropsychological tests often used to assess medial temporal and frontal function. The results suggest that adequate feature binding is particularly important when items from different source share similar features and access-evaluation processes are particularly important after a delay.

Parsing surrounding space into regions.

Surrounding space is not inherently organized, but we tend to treat it as though it consisted of regions (e.g., front, back, right, and left). The current studies show that these conceptual regions have characteristics that reflect our typical interactions with space. Three experiments examined the relative sizes and resolutions of front, back, left, and right around oneself. Front, argued to be the most important horizontal region, was found to be (a) largest, (b) recalled with the greatest precision, and (c) described with the greatest degree of detail. Our findings suggest that some of the characteristics of the category model proposed by Huttenlocher, Hedges, and Duncan (1991) regarding memory for pictured circular displays may be generalized to space around oneself. More broadly, our results support and extend thespatial framework analysis of representation of surrounding space (Franklin & Tversky, 1990).

Reality monitoring of physically similar and conceptually related objects

Three studies showed that information used in determining a target memory’s source may be derived not only from the target event itself, but also from other nontarget events or memories. Subjects were more likely to claim that an imagined object was perceived when it physically resembled or was conceptually related to another specific item that was actually perceived, relative to when there was no physical resemblance or semantic relation. Furthermore, error rates for imagined items increased with the number of perceived items that they resembled. However, subjects’ orienting task at encoding (perceptually biased or perceptually plus conceptually biased) did not systematically affect error rates. The results indicate that reality monitoring decisions about a target object are influenced by similar physical and conceptual information that was derived from other objects.

Point-and-Shoot Memories The Influence of Taking Photos on Memory for a Museum Tour

Two studies examined whether photographing objects impacts what is remembered about them. Participants were led on a guided tour of an art museum and were directed to observe some objects and to photograph others. Results showed a photo-taking-impairment effect: If participants took a photo of each object as a whole, they remembered fewer objects and remembered fewer details about the objects and the objects’ locations in the museum than if they instead only observed the objects and did not photograph them. However, when participants zoomed in to photograph a specific part of the object, their subsequent recognition and detail memory was not impaired, and, in fact, memory for features that were not zoomed in on was just as strong as memory for features that were zoomed in on. This finding highlights key differences between people’s memory and the camera’s “memory” and suggests that the additional attentional and cognitive processes engaged by this focused activity can eliminate the photo-taking-impairment effect.

Reading is believing: The truth effect and source credibility

Five experiments explored how source reliability influences peoples tendency to rate statements as more credible when they were encountered earlier (the truth effect). Undergraduates read statements from one reliable source and one unreliable source. Statements read multiple times were perceived as more valid and were more often correctly identified on a general knowledge test than statements read once or not at all. This occurred at varying retention intervals whether the statements originated from a reliable or unreliable source, when people had little memory for the statements themselves or their source, and when the discrediting information about the sources came either before or after reading the facts. While repetition aided recognition and source accuracy, both were unaffected by the reliability of the source. Consistent with the source monitoring framework, familiarity may create an illusion of truth for statements when people lack source-specifying cues, especially cues regarding the reliability of the source.

Collaborative remembering in older adults: age-invariant outcomes in the context of episodic recall deficits.

Rapidly growing research reveals complex yet systematic consequences of collaboration on memory in young adults, but much less is known about this phenomenon in older adults. Young and older adults studied a list of categorized words and took three successive recall tests. Test 1 and 3 were always taken individually, and Test 2 was done either in triads or alone. Despite older adults recalling less overall than young adults, both age groups exhibited similar costs and benefits of collaboration: Collaboration reduced both correct and false recall during collaborative remembering, was associated with more positive beliefs about its value, and produced reminiscence, collective memory, and some forgetting in its cascading effects on postcollaborative recall. We examine the role of retrieval organization in these effects. As environmental support may play a substantial role in healthy aging, the relatively preserved effects of collaboration on memory in older adults hold promise for testing judicious uses of group remembering in aging.

The Benefits and Costs of Repeated Memory Tests for Young and Older Adults

Repeated and prolonged searches of memory can lead to an increase in how much is recalled, but they can also lead to memory errors. These 3 experiments addressed the costs and benefits of repeated and prolonged memory tests for both young and older adults. Participants saw and imagined pictures of objects, some of which were physically or conceptually similar, and then took a series of repeated or prolonged recall tests. Both young and older adults recalled more on later tests than on earlier ones, though the increase was less marked for older adults. In addition, despite recalling less than did young adults, older adults made more similarity-based source misattributions (i.e., claiming an imagined item was seen if it was physically or conceptually similar to a seen item). Similar patterns of fewer benefits and more costs for older adults were seen on both free and forced recall tests and on timed and self-paced tests. Findings are interpreted in terms of age-related differences in binding processes.

The role of free choice in memory for past decisions

After choosing between different options, people tend to remember the features of the options in ways that favour the chosen alternative. The present experiment examined how limitations on freedom to choose between options affected this memory bias. Participants were given a series of two-option choices and were either allowed free choice between options or were assigned to an option. Participants assigned to an option were led to believe that either the selection was random or was made in their best interest based on their personality profile. Results indicated that the choice and best interest conditions demonstrated memory attributions that favoured their received options, whereas the assignment condition did not. These findings support the view that memory biases towards received options are not unique to free choice situations, but may stem from expectations and implicit theories about how and why the choice was made.

Maximizing the Benefits and Minimizing the Costs of Repeated Memory Tests for Older Adults

Repeatedly trying to remember information can help people remember more but can also lead to inaccuracies. Two experiments examined whether the costs of repeated recall efforts can be minimized for older adults by using memory tests that require specification of the source of recalled items. Participants saw and imagined pictures and then took 3 successive recall tests in which they either indicated the source of each remembered item (source recall) or simply recalled the items without specification of their source (free recall). Results showed that recall increased systematically from Test 1 to Test 3, although the rate of increase was less marked for older adults, and older adults recalled less overall. After the free recall tests, older adults made more source misattributions (claiming to have seen imagined items) than did young adults, but after the source recall tests, age differences were not significant. Thus, repeatedly recalling items while considering their source was associated with benefits in terms of increased recall and fewer costs in terms of source errors.