Episodic future thought: Contributions from working memory

The ability to imagine hypothetical events in one’s personal future is thought to involve a number of constituent cognitive processes. We investigated the extent to which individual differences in working memory capacity contribute to facets of episodic future thought. College students completed simple and complex measures of working memory and were cued to recall autobiographical memories and imagine future autobiographical events consisting of varying levels of specificity (i.e., ranging from generic to increasingly specific and detailed events). Consistent with previous findings, future thought was related to analogous measures of autobiographical memory, likely reflecting overlapping cognitive factors supporting both past and future thought. Additionally, after controlling for autobiographical memory, residual working memory variance independently predicted future episodic specificity. We suggest that when imagining future events, working memory contributes to the construction of a single, coherent, future event depiction, but not to the retrieval or elaboration of event details.     

The role of executive function in autobiographical memory retrieval: does the type of cue word matter?

ABSTRACT

Autobiographical memories are memories for personally experienced life events. Previous research has revealed individual differences in the ability to recall specific memories that happened at a particular time and place. Some studies suggest such differences can be attributed to the varying capacity of executive function. However, little is known regarding which specific executive function skills predict autobiographical memory specificity. Participants were asked to complete multiple measures of executive function as well as an autobiographical memory task in which they were asked to recall a specific personal memory connected to concrete and abstract cue words. We hypothesised that executive function will be positively related to autobiographical memory specificity and that this relation will be moderated by the cue word type. The results revealed that individuals with higher executive function skills, specifically, higher inhibitory control and cognitive flexibility, recalled significantly more specific memories than those with lower executive function skills; however, no significant interaction between executive function ability and cue word type was found.     

Scope of attention, control of attention, and intelligence in children and adults

Recent experimentation has shown that cognitive aptitude measures are predicted by tests of the scope of an individual's attention or capacity in simple working memory tasks and also by the ability to control attention. However, these experiments do not indicate how separate or related the scope and control of attention are. An experiment with 52 children (10 to 11 years old) and 52 college students included measures of the scope and control of attention, as well as verbal and nonverbal aptitude measures. The children showed little evidence of using sophisticated attentional control, but the scope of attention predicted intelligence in that group. In adults, both the scope and control of attention varied among individuals and accounted for considerable individual variance in intelligence. About one third that variance was shared between scope an d control, and the rest was unique to one or the other.Scope and control of attention appear to be related but distinct contributors to intelligence.     

Autobiographical memory specificity predicts social problem-solving ability in old and young adults

Based on recent research with young, depressed adults, age-related cognitive declines and decreased autobiographical specificity were hypothesized to predict poorer social problem-solving ability in older than in younger healthy adults. Priming autobiographical memory (ABM) was hypothesized to improve social problem-solving performance for older adults. Subsequent to cognitive tests, old and young participants' specific ABMs were tested using a cued recall task, followed by a social problem-solving task. The order of the tasks was counterbalanced to test for a priming effect. Autobiographical specificity was related to cognitive ability and predicted social problem-solving ability for both age groups. However, priming of ABM did not improve social problem-solving ability for older or younger adults. This study provides support for the hypothesis that autobiographical memory serves a directive function across the life-span.     

Is overgeneral autobiographical memory an isolated memory phenomenon in major depression?

The present study explored the relation between overgeneral autobiographical memory (AM) and other aspects of memory functioning in depression. A total of 26 patients with major depressive disorder completed a set of memory tasks measuring AM specificity (AMT; Williams & Broadbent, 1986), working memory, semantic memory, verbal learning, delayed verbal recall, recognition memory, and source memory. Reduced specificity of AM was related to poor working memory (central executive functioning) and poor source memory. The former finding conforms to the idea that the voluntary retrieval of specific autobiographical memories (AMs) involves central executive processes (e.g., Conway & Pleydell-Pearce, 2000). The latter finding replicates and extends recent findings suggesting that overgeneral AM is part of a broader memory deficit in retrieving the specific details of the context in which information was acquired (Ramponi, Barnard, & Nimmo-Smith, 2004). Furthermore, in line with Ramponi et al. (2004), rumination was found to be related to both overgeneral AM and poor source memory.     

Autobiographical memory specificity predicts social problem-solving ability in old and young adults

Based on recent research with young, depressed adults, age-related cognitive declines and decreased autobiographical specificity were hypothesized to predict poorer social problem-solving ability in older than in younger healthy adults. Priming autobiographical memory (ABM) was hypothesized to improve social problem-solving performance for older adults. Subsequent to cognitive tests, old and young participants' specific ABMs were tested using a cued recall task, followed by a social problem-solving task. The order of the tasks was counterbalanced to test for a priming effect. Autobiographical specificity was related to cognitive ability and predicted social problem-solving ability for both age groups. However, priming of ABM did not improve social problem-solving ability for older or younger adults. This study provides support for the hypothesis that autobiographical memory serves a directive function across the life-span.     

Role of anxiety and brooding in specificity of autobiographical recall

Overgeneral schemas and lack of autobiographical memory (AM) specificity about our past experiences can predict mood disturbance. Rumination, functional avoidance and executive processes are the main explanatory variables of such overgenerality. However, in non‐clinical samples, rumination predicts overgenerality most consistently after the induction of dysphoric mood. Anxiety also activates rumination. Furthermore, anxiety predicts memory performance and has effects on mood which are independent of the effects of rumination. So, what might be the role of anxiety in autobiographical memory performance? A sample of 210 voluntary participants reported measures of autobiographical memory, anxiety, rumination (brooding and reflection), functional avoidance and executive functions (semantic and phonetic verbal fluency task). Autobiographical performance (specificity) was negatively associated with brooding and age and positively with phonetic verbal fluency but not with functional avoidance and anxiety. However, anxiety and brooding were positively correlated even after controlling for depression scores. Moreover, using structural equation modeling, anxiety showed a significant indirect effect on autobiographical specificity through brooding rumination. These results suggest a possible association of anxiety with autobiographical recall through brooding rumination.     

Overgeneral autobiographical memory recollection in Iranian combat veterans with posttraumatic stress disorder

This study examined the recollection of autobiographical material in memory among Iranian military veterans with and without posttraumatic stress disorder (PTSD), and healthy non-trauma-exposed control subjects. Participants completed the Autobiographical Memory Test, Autobiographical Memory Interview (counterbalanced), Impact of Event Scale-Revised, Beck Depression Inventory-II, Wechsler Memory Scale-III and Wechsler Adult Intelligence Scale-Revised. The PTSD group generated fewer specific episodic and semantic details of autobiographical memory compared to the non-PTSD and control groups. Working memory did not significantly moderate the relationship between PTSD diagnosis and reduced autobiographical memory specificity but did moderate the relationship between PTSD diagnosis and semantic recall; semantic memory recall was not significantly related to working memory ability for those with PTSD but was related to working memory ability for trauma survivors without PTSD. While the data provide some support for the expectation that higher working memory ability is associated with an increased ability to retrieve specific memories (i.e. semantic memory recall in those without PTSD), the findings are also consistent with the view that for those with PTSD the demands on working memory required for affect regulation cancel out this influence of working memory in augmenting access to specific memories.     

Quantity,not quality: the relationship between fluid intelligence and working memory capacity

A key motivation for understanding capacity in working memory (WM) is its relationship with fluid intelligence. Recent evidence has suggested a two-factor model that distinguishes between the number of representations that can be maintained in WM and the resolution of those representations. To determine how these factors relate to fluid intelligence, we conducted an exploratory factor analysis on multiple number-limited and resolution-limited measures of WM ability. The results strongly supported the two-factor model, with fully orthogonal factors accounting for performance in the number-limited and resolution-limited conditions. Furthermore, the reliable relationship between WM capacity and fluid intelligence was exclusively supported by the number factor (r=.66), whereas the resolution factor made no reliable contribution (r=−.05). Thus, the relationship between WM capacity and standard measures of fluid intelligence is mediated by the number of representations that can be simultaneously maintained in WM, rather than by the precision of those representations.     

Individual differences in children's event memory reports and the narrative elaboration technique

Children between 7 and 8 years old took part in a staged event at school and 1 week later were assessed using a short form of the Wechsler Intelligence scale for children (third edition) and measures of metamemory, narrative ability, and socioeconomic status. Two weeks following the event, children either received narrative elaboration training (NET; K.J. Saywitz & L. Snyder, 1996) and were prompted with the four NET cue cards at interview; received verbal prompts corresponding to the cue card categories, but without prior training; or were presented with the cards at interview without prior training. Children given verbal labels as prompts recalled as much information as children who received NET training and cue cards. Measures of intelligence were predictive of amount recalled for cards-only children but not for the other 2 groups, indicating that differences in recall between low- and high-IQ groups were attenuated when recall was supported by NET training or verbal prompting.     

Thought suppression,intelligence, and working memory capacity

The importance of individual differences in intelligence and working memory capacity in predicting the ability to intentionally suppress thoughts was investigated. Sixty participants completed a thought suppression task, and measures of working memory capacity (OSPAN), fluid intelligence (Raven's Matrices), and crystallised intelligence (the National Adult Reading Test). As predicted, the results indicated that more effective thought suppression was independently related to higher working memory capacity and greater fluid intelligence, but was unrelated to crystallised intelligence. The findings have theoretical implications for understanding the mechanisms underlying a failure to inhibit unwanted intrusions and clinical implications for disorders involving high levels of intrusive thoughts and memories.     

Eyewitness memory and aging: predictors of accuracy in recall and person recognition.

This study examined adult age differences in identification accuracy, confidence, and verbal recall of crime films. A total of 120 Ss in 3 adult age groups watched 2 crime films that contained characters varying in role and visibility. Results suggested a modest negative relationship between age and identification accuracy but no age differences in recall of main points or details. Education and self-reported health positively predicted verbal recall, but higher education was associated with lower identification accuracy. No age differences were found in confidence or in the relationship between confidence and accuracy.     

Individual differences in cognition: Relationship between verbal ability and memory for order

The crucial role of order information in language has led to the suggestion that psychometrically measured verbal ability may be related to memory for order. The literature pertaining to this hypothesis is briefly reviewed and various methodological difficulties discussed. The results of three experiments indicated that (a) order and item information may be retained separately; (b) verbal ability is related to the short-term recall of order; (c) verbal ability is unrelated to memory for order when testing involves recognition rather than recall; and (d) the relationship between verbal ability and memory for order is most pronounced when the originally presented order must be transformed at output (as in the “digits backward” task). An output process in which material is decoded and held in an output buffer until decoding is complete is viewed as the most likely locus of the verbal ability-memory for order relationship.     

Effects of verbal ability and fluid intelligence on children's emotion understanding

This study investigated the role of verbal ability and fluid intelligence on children's emotion understanding, testing the hypothesis that fluid intelligence predicts the development of emotion comprehension over and above age and verbal ability. One hundred and two children (48 girls) aged 3.6–6 years completed the Test of Emotion Comprehension (TEC) that comprised external and mental components, the Coloured Progressive Matrices and the Test for Reception of Grammar. Regression analysis showed that fluid intelligence was not equally related to the external and mental components of the TEC (Pons & Harris, 2000). Specifically, the results indicated that the external component was related to age and verbal ability only, whereas recognition of mental emotional patterns required abstract reasoning skills more than age and verbal ability. It is concluded that the development of fluid intelligence has a significant role in the development of mental component of emotion comprehension.     

Tunnel memories for autobiographical events: central details are remembered more frequently from shocking than from happy experiences

In three experiments, undergraduates recorded as many details as possible for autobiographical memories of highly positive and highly negative events in their lives. Experiment 1 replicated earlier findings for memories of highly negative events: Central details were recorded more frequently than peripheral details, and a weak correlation was found between emotional intensity and number of central details. In Experiment 2, undergraduates recorded details of memories of both their happiest and their most shocking events. Central details dominated over peripheral details only in memories of shocking events. This finding was replicated in Experiment 3. Recording memory details affected the participants' moods and generated a mood congruence effect in a subsequent recall of word-cued memories. The finding suggest that tunnel memories--enhanced memory for the central details of an event--are limited to emotionally negative memories. The findings contradict expectations derived from the notion of repression.     

Contributions of processing ability and knowledge to verbal memory tasks across the adult life-span

This study investigated the relationships of processing capacity and knowledge to memory measures that varied in retrieval difficulty and reliance on verbal knowledge in an adult life-span sample (N = 341). It was hypothesized that processing ability (speed and working memory) would have the strongest relationship to tasks requiring active retrieval and that knowledge (vocabulary ability) would be related to verbal fluency and cued recall, as participants relied upon verbal knowledge to retrieve category items (fluency) or develop associations (cued recall). Measurement and structural equation models were developed for the entire sample and separately for younger (aged 20-54 years, n = 168) and older (aged 55-92 years, n = 173) subgroups. In accordance with the hypotheses, processing ability was found to be most highly related to free recall, with additional significant relationships to cued recall, verbal fluency, and recognition. Knowledge was found to be significantly related only to verbal fluency and to cued recall. Moreover, knowledge was more important for older than for younger adults in mediating variance in cued recall, suggesting that older adults may use age-related increases in knowledge to partially compensate for processing declines when environmental support is available in memory tasks.     

Intelligence and changes in regional cerebral glucose metabolic rate following learning

Positron emission tomography (PET) studies of brain glucose metabolic rate (GMR) in normal volunteers report inverse correlations between GMR and scores on the Raven's Advanced Progressive Matrices (RAPM) and verbal fluency. A new study in eight normal men reports widespread significant GMR decreases following learning a complex task (the computer game “Tetris”). The purpose of this study is to ascertain the correlations between GMR changes following learning “Tetris” and psychometric intelligence scores (RAPM and WAIS-R) to determine whether high-ability subjects show the largest GMR decreases, as predicted by a brain efficiency hypothesis. This hypothesis is supported with significant correlations between the magnitude of GMR change and intelligence scores in many brain areas that changed with learning. Some implications for the role of attention, memory, and speed of processing are discussed in view of the specific brain areas involved.     

A matter of focus: Detailed memory in the intentional autobiographical recall of older and younger adults

The intricately interwoven role of detailed autobiographical memory in our daily lives and in our imaginative envisioning of the future is increasingly recognized. But how is the detail-rich nature of autobiographical memory best assessed and, in particular, how can possible aging-related differences in autobiographical memory specificity be most effectively evaluated? This study examined whether a modified interview, involving fewer and time-matched events for older and younger adults, yielded age-related outcomes similar to those that have been previously reported. As in earlier studies, modest age-related changes in the specificity of autobiographical recall were observed, yet the largest most robust effect for both age groups was the substantial proportion of specific details retrieved. Both age groups rated recent memories as significantly less important and as less emotional than more temporally distant events. Our findings counter conceptions of older adults’ autobiographical memories as invariably less episodically rich than those of younger adults.     

Constructing a past in infancy: a neuro-developmental account

The ability to recall the past is fundamental yet until relatively recently, infants were assumed to lack the capacity. Contrary to this perspective, non-verbal tests indicate that developments in recall are well underway by late in the first year of life; by the end of the second year, long-term recall is reliable and robust. New research combining electrophysiological and behavioral measures is identifying the loci of age-related changes: they are attributed to more effective and efficient encoding, consolidation and storage processes associated with developments in the temporal-cortical network that subserves recall. The emerging framework, which applies to episodic and autobiographical memory, highlights the essential developmental continuities in memory from infancy onwards and sheds new light on the phenomenon of childhood amnesia.     

Ageing and autobiographical memory for emotional and neutral events

We investigated age-related effects in recall of emotional and neutral autobiographical memories. Protocols were scored according to episodic and non-episodic detail categories using the Autobiographical Interview. Young adults recalled a greater number of episodic details compared to older adults, whereas older adults recalled more semantic details, replicating previous findings. Both young and older adults' emotional memories contained more overall detail than neutral ones, with the enhancement from emotion-specific to episodic details, but this did not alter the effect of age group on the pattern of episodic and semantic details. However, the age effect on episodic details was attenuated for neutral autobiographical memories. The findings suggest that age differences for emotional autobiographical recollection might reflect a more general pattern of age-related changes in memory, with impaired recall of episodic components and relative sparing of semantic aspects of autobiographical memory in older adults when compared to young adults.