Biomedical subjects

S S Wewerka

Publications and source records attributed to S S Wewerka.

6 recordsLinked to original sources

PubMed2000

Parameters of remembering and forgetting in the transition from infancy to early childhood.

The ability to recall is something that most intact adults take for granted. For much of the last century, this feature of mental life was not considered to extend to very young children. There now is evidence that 1- to 2-year-olds are able to recall specific events after delays of several months. Over the short term, 1- to 2-year-olds' recall is affected by the same factors that affect older children's recall; it is not clear whether similar effects are apparent over the long term. Moreover, although age-related increases in long-term recall are assumed, there have been few empirical tests of the question. We examined recall by 14- to 32-month-olds for events experienced at 13 to 20 months. Using elicited imitation of novel multistep event sequences we examined effects of (a) delay length, (b) age at the time of experience, (c) temporal structure of events, (d) mode of experience of events, and (e) availability of verbal reminders, on long-term recall. Participants were 360 children enrolled at 13 (n = 90), 16 (n = 180), and 20 (n = 90) months. All of the 13-month-olds and half of the 16-month-olds were tested on 3-step event sequences; all of the 20-month-olds and half of the 16-month-olds were tested on 4-step event sequences. Within each age and step-length group, equal numbers of children were tested after intervals of 1, 3, 6, 9, and 12 months (n = 18 per cell). Children were tested on a variety of sequence types. For half of the events, imitation was permitted prior to the delay; for the other half, children were not permitted imitation. At delayed testing, children experienced a recall period during which they were cued by the event-related props alone, followed by a period in which recall was cued both by the event-related props and by verbal labels for the event sequences. Within step-length groups, the length of time for which older and younger children showed evidence of memory did not differ. Nevertheless, when the children were prompted by the event-related props alone, there were age-related differences in the robustness of children's memories (as indexed by higher levels of recall for older children relative to younger children). When the children were prompted by the props and by verbal labels for the event sequences, at the longer retention intervals, there were age-related differences in the robustness of children's memories and in the reliability with which recall was evidenced (as indexed by the larger numbers of older children evincing recall). Age-related effects were particularly apparent on children's ordered recall. Across the entire age range, the children were similarly affected by the variables of sequence type, opportunity for imitation, and verbal reminding.

Child, Preschool↗

PubMed1999

Planning ahead: goal-directed problem solving by 2-year-olds.

On tasks that require overcoming an obstacle along an existing path to a physically present goal, infants and very young children evince planning. In each of 3 experiments, the authors tested 21- and 27-month-olds' ability to construct a path to a mentally re-presented goal. Across experiments, the authors varied the number and type of cues to the solution provided. After exposure to the goal-state configuration of problems, both age groups showed evidence of planning (Experiment 1). Demonstration of the initial step in the solution path in Experiment 2 was not as effective as exposure to the goal state in Experiment 1. Even with specification of a greater proportion of the goal path, goal-state configuration information was particularly effective in facilitating performance (Experiment 3). The results suggest productive generation of solutions to novel problems by young children; planning is facilitated by goal-state configuration information.

Child Behavior↗

PubMed1998

Delayed recognition memory in infants and adults as revealed by event-related potentials.

The present study sought to compare adult and infant ERP responses in analogous tests of visual recognition memory. Adults were tested under two test conditions, in which they were given either explicit instructions to respond to a previously-seen stimulus, or no instructions. Testing in both conditions took place after either a 1- or 5-min delay between familiarization and test. Eight-month-old infants were tested under the same 'passive' (no instruction) conditions as adults. ERP morphology differed across age groups. Adults evinced a P300 that was larger under 'active' as compared to 'passive' test conditions, and a late positive slow wave response that was greater to novel than familiar stimuli. There was no evidence in infants of a P300, although infants did demonstrate a late positive slow wave that was greater to familiar than to novel stimuli. Parallels between the infant and adult findings are discussed and in particular, whether the infant slow wave response is the precursor to the adult P300.

Adolescent↗

PubMed1998

If memory serves, will language? Later verbal accessibility of early memories.

Of major interest to those concerned with early mnemonic process and function is the question of whether early memories likely encoded without the benefit of language later are accessible to verbal report. In the context of a controlled laboratory study, we examined this question in children who were 16 and 20 months at the time of exposure to specific target events and who subsequently were tested for their memories of the events after a delay of either 6 or 12 months (at 22-32 months) and then again at 3 years. At the first delayed-recall test, children evidenced memory both nonverbally and verbally. Nonverbal mnemonic expression was related to age at the time of test; verbal mnemonic expression was related to verbal fluency at the time of test. At the second delayed-recall test, children evidenced continued accessibility of their early memories. Verbal mnemonic expression was related to previous mnemonic expression, both nonverbal and verbal, each of which contributed unique variance. The relevance of these findings on memory for controlled laboratory events for issues of memory for traumatic experiences is discussed.

Child, Preschool↗

PubMed1995

Effects of experience and reminding on long-term recall in infancy: remembering not to forget.

We examined whether some of the factors that facilitate recall in older children also extend to 1- to 2-years-olds. Using elicited imitation we assessed the efficacy of verbal (Experiment 1), and verbal plus nonverbal (Experiment 2) reminding on 15-month-olds' recall after a 1-week delay. Reminding ameliorated forgetting: Performance at delayed and immediate recall was equivalent. The addition of nonverbal information did not enhance recall above verbal information alone. In Experiment 3 we investigated the influence of verbal reminding, repeated experience, and mode of experience (i.e., imitate vs watch only) on recall after 1 month. The effects of reminding depended on event type: Reminding facilitated recall of events with enabling relations, but not of events lacking them. Repeated experience and the opportunity to imitate facilitated recall; children who watched events only once nevertheless recalled them. Results suggest that the strength of organization of an event representation, rather than retention interval, is a major determinant of remembering during the second year of life.

Attention↗

PubMed1995

One- to two-year-olds' recall of events: the more expressed, the more impressed.

The literature on stylistic differences in mother-child conversations about ongoing and past events can be interpreted to suggest that the opportunity to verbally elaborate on an event facilitates preschoolers' memory. In this research we examined whether similar effects would obtain in children who are just acquiring language and, thus, the opportunity for verbal encoding. Using elicited imitation, 12 groups, formed by a between-subjects crossing of 3 levels of age (13, 16, and 20 months) with 4 levels of delay (1-3, 6, 9, and 12 months), were tested for memory for specific laboratory events; children's event-relevant verbalizations also were recorded. The children remembered the events that they had experienced, regardless of their age at the time of exposure and of the delay interval imposed. Memories were demonstrated both nonverbally and verbally; nonverbal and verbal measures bore a modest relation with one another. Language ability at the time of exposure to the events predicted verbal expression of memory after the delay. Thus, the availability of a verbal mode of elaboration facilitated 1- to 2-year-olds' event memory.

Female↗