Adaptive memory: survival processing enhances retention

The authors investigated the idea that memory systems might have evolved to help us remember fitness-relevant information--specifically, information relevant to survival. In 4 incidental learning experiments, people were asked to rate common nouns for their survival relevance (e.g., in securing food, water, or protection from predators); in control conditions, the same words were rated for pleasantness, relevance to moving to a foreign land, or personal relevance. In surprise retention tests, participants consistently showed the best memory when words were rated for survival; the survival advantage held across recall, recognition, and for both within-subject and between-subjects designs. These findings suggest that memory systems are "tuned" to remember information that is processed for fitness, perhaps as a result of survival advantages accrued in the past.     

Adaptive memory: enhanced location memory after survival processing

Two experiments investigated whether survival processing enhances memory for location. From an adaptive perspective, remembering that food has been located in a particular area, or that potential predators are likely to be found in a given territory, should increase the chances of subsequent survival. Participants were shown pictures of food or animals located at various positions on a computer screen. The task was to rate the ease of collecting the food or capturing the animals relative to a central fixation point. Surprise retention tests revealed that people remembered the locations of the items better when the collection or capturing task was described as relevant to survival. These data extend the generality of survival processing advantages to a new domain (location memory) by means of a task that does not involve rating the relevance of words to a scenario.     

Adaptive memory: enhanced source memory for animate entities

ABSTRACT

The animacy effect refers to enhanced memory for animate over inanimate items. In two studies, we examined whether this memory advantage generalises to source memory. A multinomial processing tree model was used to disentangle item recognition, source memory, and guessing processes. In Study 1, animate and inanimate words were presented at different spatial locations on the screen. Animacy was associated with enhanced source memory for the spatial locations of the items. In Study 2, pseudowords were associated with animate and inanimate properties. Replicating previous results, the pseudowords were better remembered when they were associated with animate properties than when they were associated with inanimate properties. What is more, participants had enhanced source memory for the association between the pseudowords and the animate properties. The results strengthen the idea that animate items are associated with richer mnemonic representations than inanimate items.     

Adaptive memory: fitness relevant stimuli show a memory advantage in a game of pelmanism

A pelmanism (matched-pairs) game was used in order to test the hypothesis that survival-relevant stimuli that are likely to have been present during human evolution (e.g., a snake in attack position) enjoy a memory advantage over other survival-relevant (but “modern”) stimuli (e.g., a threatening image of a gunman). Survival-relevant stimuli were matched for arousal and presented in one of two 5 x 4 grids, along with filler items. Participants were asked to match the pairs in the grids by clicking on successive squares to reveal stimuli. Participants made significantly fewer errors when matching evolutionarily relevant survival stimuli than when matching the other stimuli. Additionally, on incorrect trials, the attempted matches were significantly closer to the actual locations of evolutionarily relevant targets than to those of other stimuli. The results suggest that objects that likely posed a consistent threat throughout human evolutionary history are better remembered than other, equally arousing and survival-relevant, stimuli. [corrected]     

Recognition memory retention interval and information load

Two experiments were conducted to study the effect of retention interval and information load on short-term recognition memory in retarded subjects. The task consisted of an input trial of 1–15 pictures followed by a test trial of one picture, with the subject having to press different levers to indicate whether the probe picture had been present on the input trial. Retention intervals between input trial and test trial were manipulated over a range of 1–24 sec. Both accuracy and latency of response were measured. Results showed that latency increased and accuracy decreased as a function of both retention interval and number of stimuli. In addition, number of stimuli interacted with retention interval such that accuracy was not affected by retention interval when information input was small, but decreased quite dramatically at longer retention intervals when input was larger. The results were discussed in terms of current memory search models for both normal and retarded subjects.     

Arousal enhanced memory retention is eliminated following temporal lobe resection

The amygdala, situated in the anterior medial temporal lobe (MTL), is involved in the emotional enhancement of memory. The present study evaluated whether anterior MTL-resections attenuated arousal induced memory enhancement for pictures. Also, the effect of MTL-resections on response latencies at retrieval was assessed. Thirty-one patients with unilateral MTL-resections (17 left, 14 right) together with 16 controls participated in a forced choice memory task with pictorial stimuli varying in arousal. Response latencies increased with stimulus arousal in controls but not in patients. This was paralleled by attenuated recognition memory for moderately and highly arousing pictures in MTL-resectioned patients as compared to healthy controls. However, patients and controls did not differ in memory performance for non-arousing pictures. These results suggest that the MTL is necessary for arousal induced memory enhancement.     

Affect and memory in young children

The state-dependent theory of the relationship between affective states and memory holds that recall will be best when the affective state at recall matches that during learning. Sequential happy, neutral, and sad affective states that were either consistent (e.g., Happy-Happy) or inconsistent (e.g., Sad-Neutral) were experimentally induced in preschool children prior to encoding and then again prior to retrieval (free and cued recall, recognition memory). Facial ratings indicated that the inductions were effective in inducing affect. Nevertheless, emotional states did not influence children's ability to recall items under free or cued conditions, and recognition memory was essentially perfect for all subjects. Thus, there was no evidence for state-dependent learning or for a positive loop between subjects' positive affect at retrieval and memory for positively rated information. Results are discussed in terms of the generally inconsistent findings in the literature on the role of affect in children's memory and factors that may limit affective state-dependent learning in children.This research was supported by Research Grant No. 11776 from the National Institute of Child Health and Human Development to Marion Perlmutter, by Grant BNS 78-01108 from the National Science Foundation to John C. Masters, and by Program Project Grant No. 0527 to the Institute of Child Development. Wayne Duncan is now at the University of Denver, and Christine Todd is now at the University of Illinois, Urbana. Marion Perlmutter is now at the University of Michigan. We would like to thank Keith Elliott and LuAnne Tczap for their work as experimenters; Jule Kogan, Carol Revermann, and Sonya Hernandez for their help in coding data; and Jayne Grady-Reitan for her administrative assistance throughout the study.     

Visual working memory in young children

Five experiments investigated immediate memory for drawings of familiar objects in children of different ages. The aims were to demonstrate younger children’s greater dependence on visual working memory and to explore the nature of this memory system. Experiment 1 showed that visual similarity of drawings impaired recall in young (5-year-old) children but not in older (10-year-old) children. Experiment 2 showed that younger and older children were affected in contrasting ways when the temporal order of recall was manipulated. Experiment 3 explored a recency effect found in backward recall and investigated its sensitivity to the presentation modality of materials used to produce retroactive interference (RI). For younger children, recency was reduced by visual but not by auditory-verbal RI; for older children, recency was more sensitive to auditoryverbal RI. Experiment 4 confirmed the effect of visual RI on visual recency in young children and showed that the same RI had little effect on their recall of spoken words. These results confirm younger children’s dependence on visual working memory. A final experiment showed that the effects of visual similarity and visual RI are additive, suggesting that they reflect different modes of accessing stored visuospatial information. Implications of these findings for developmental issues and for the nature of visual working memory are discussed.     

Emotional mood and memory in young children

Two experiments examined affect-dependent memory with preschool/kindergarten and third-grade children. A two-list intentional learning procedure was used to assess the effects of the congruent versus incongruent relationship between affect (happy vs sad) during initial list learning and affect (happy vs sad) during a delayed recall test. When induction of emotional mood was preceded by relaxation exercises in Experiment 1, no evidence of affect dependence was observed. When the relaxation procedure was omitted in Experiment 2, the affect-dependent pattern was obtained in both free recall and cued recall for both age groups. The results of Experiment 2 show that affect-dependent memory is a reasonably robust phenomenon in children and that hypnosis is not necessary for its appearance. However, the phenomenon is apparently absent under conditions of relaxation, a result consistent with two-factor theories of emotion.     

Blocking of incidental information in young children

Methods of increasing learning efficiency through a blocking technique were examined in young children. An experimental group of children was trained on an initial task with one relevant dimension, followed by redundancy training in which an incidental dimension also became relevant. A control group given only redundancy training was compared to this group to test how much the experimental subjects blocked or screened out the incidental dimension. In order to increase blocking, three methods were used: a preset transfer problem, an overtraining on the initial task, and a delay following training. The most important finding was increased blocking through the Preset Condition. Overtraining and Delay Conditions had no effect. In addition, more slow learners on the initial task learned about the incidental dimension than fast or intermediate learners. Also, fewer subjects given form on the initial task learned about the incidental dimension than those given color. The Combined Blocking, Delay, and Overtraining group showed partial blocking, while the Preset group demonstrated complete blocking. No developmental differences occurred. The results were interpreted using a modification of Trabasso and Bower's attention model (Attention in learning: Theory and research. New York: Wiley, 1968).     

Opening the cuebox: The information children and young adults generate and rely on when making inferences from memory

We used a cue‐generation and a cue‐selection paradigm to investigate the cues children (9‐ to 12‐year‐olds) and young adults (17‐year‐olds) generate and select for a range of inferences from memory. We found that children generated more cues than young adults, who, when asked why they did not generate some particular cues, responded that they did not consider them relevant for the task at hand. On average, the cues generated by children were more perceptual but as informative as the cues generated by young adults. When asked to select the most informative of two cues, both children and young adults tended to choose a hidden (i.e., not perceptual) cue. Our results suggest a developmental change in the cuebox (i.e., the set of cues used to make inferences from memory): New cues are added to the cuebox as more cues are learned, and some old, perceptual cues, although informative, are replaced with hidden cues, which, by both children and young adults, are generally assumed to be more informative than perceptual cues.     

Working memory and fluid intelligence in young children

The present study investigates how working memory and fluid intelligence are related in young children and how these links develop over time. The major aim is to determine which aspect of the working memory system—short-term storage or cognitive control—drives the relationship with fluid intelligence. A sample of 119 children was followed from kindergarten to second grade and completed multiple assessments of working memory, short-term memory, and fluid intelligence. The data showed that working memory, short-term memory, and fluid intelligence were highly related but separate constructs in young children. The results further showed that when the common variance between working memory and short-term memory was controlled, the residual working memory factor manifested significant links with fluid intelligence whereas the residual short-term memory factor did not. These findings suggest that in young children cognitive control mechanisms rather than the storage component of working memory span tasks are the source of their link with fluid intelligence.     

Implicit long-term memory for duration in young children

The aim of the present study was to investigate young children's ability to maintain in long-term memory a duration of an action they have previously experienced (i.e., implicit long-term memory for duration). Children aged 3 and 5 years were trained to produce an action for 5 s by simultaneous imitation of the experimenter's action. Then, they were tested after a retention interval lasting for 1, 24, or 48 hours (Experiment 1), or 6 days, 6 weeks, or 6 months (Experiment 2). The results showed that the young children remembered the learned duration after 48 hours and 6 months at the age of 3 and 5 years, respectively, although the temporal performance decreased at the 1 hour and the 6 weeks retention intervals for the first and the second age group. These findings are discussed in the framework of a discrepancy in the memory retention of duration as a function of the nature of the memory system, i.e., implicit or explicit.     

Executive functioning and prospective memory in young children

The current study examined the role of executive functioning (EF) in children's prospective memory (PM) by assessing the effect of delay and number of intentions to-be-remembered on PM, as well as relations between PM and EF. Ninety-six 4-, 5-, and 6-year-olds completed a PM task and two executive function tasks. The PM task required children to interrupt an ongoing card game to perform one action (single intention) or two actions (dual intention) with target cards after a short delay (1 min) or a long delay (5 min). There was no main effect of number of intentions or delay on the PM task. However, performance improved with age, and age and delay interacted such that 4-year-olds’ performance remained the same after a long delay whereas 5-year-olds’ performance improved after a long delay. We suggest that the age by delay interaction is a product of age differences in cognitive monitoring. Working memory but not inhibitory control predicted PM with age controlled. We argue that an executive function framework permits an integrative understanding of many processes involved in young children's prospective memory.     

A timing-specific memory distortion effect in young children

It has been suggested that there are systematic distortions in children's memory for temporal durations, such that children's memory is not just less accurate than that of adults but qualitatively different. Experiment 1 replicated the memory distortion effect by demonstrating developmental change in the tendency to confuse a reference duration with one that is shorter rather than longer than it. When the long-term memory demands of the task were reduced by providing reminders of the reference duration on every trial, there were no such qualitative changes in error patterns (Experiment 2). Further evidence for developmental changes in memory distortion was found in the temporal generalization task of Experiment 3, in which stimuli were spaced logarithmically rather than linearly. In Experiment 4, a similar distortion pattern was absent in a task in which children made judgments about the pitch rather than the duration of stimuli, suggesting the effect may be specific to time estimation.     

Adaptive behavior in young children of emotionally disturbed women

Children of mentally-ill parents are population at increased risk for psychiatric disorder, and recent research has focused on the psychological development of these individuals. The Rochester Adaptive Behavior Inventory (RABI) was developed to measure the adaptive behavior of such high-risk children based upon a parental interview. Scales defining specific behavior spheres were reproduced in four samples of 30- and 48-month-olds. These scales differentiated high-risk children along dimensions of maternal psychopathology and social status. Global measures of maternal illness, such as severity of symptoms, proved to be more powerful than specific diagnosis. Race and socio-economic status also had a major impact on adaptive behavior. Implications of the data for high-risk theories of schizophrenia are discussed.     

Intentional and unintentional memory in young children: remembering vs. playing

In an exploration of Istomina's (1975) paradigm contrasting children's recall from an involuntary or game-like context with recall from an intentional or lesson-like context, this study investigated the relative efficacy of asking 4- and 5-year-olds "to remember" or "to play with" a set of 16 pictures or toys in a naturalistic or laboratory setting. The children's behavior and language were measured during two 2-min study phases, after which recall was assessed. Toys promoted different study phase activities and better retention than pictures, asking a child "to remember" a set of toys led to less recall than asking the child "to play" with the toys, and, across all conditions, instructions "to play" and "to remember" elicited differentiated study phase responses but similar levels of retention.     

Working memory resources in young children with mathematical difficulties

Kyttälä, M., Aunio, P. & Hautamäki, J. (2010). Working memory resources in young children with mathematical difficulties. Scandinavian Journal of Psychology, 51 , 1–15.
Working memory (WM) ( Baddeley, 1986, 1997 ) is argued to be one of the most important cognitive resources underlying mathematical competence ( Geary, 2004 ). Research has established close links between WM deficits and mathematical difficulties. This study investigated the possible deficits in WM, language and fluid intelligence that seem to characterize 4- to 6-year-old children with poor early mathematical skills before formal mathematics education. Children with early mathematical difficulties showed poor performance in both verbal and visuospatial WM tasks as well as on language tests and a fluid intelligence test indicating a thoroughly lower cognitive base. Poor WM performance was not moderated by fluid intelligence, but the extent of WM deficits was related to language skills. The educational implications are discussed.     

The effects of memory set size and information structure on learning and retention

Two experiments examined the effects of memory set size and information structure on learning and retention. Participants learned 48 (small set) or 144 (large set) facts about individuals, and were tested over 48 facts. The test facts included either 4 facts about 12 individuals (12-person condition) or 12 facts about 4 individuals (4-person condition). During learning, there was an advantage for the small-set group in the 4-person condition, but a disadvantage in the 12-person condition. During testing, there was an advantage for the 4-person condition relative to the 12-person condition for the small-set group, even when the conditions were equated in terms of name exposure. The results support a mental model account of memory representation and retrieval.