Nancy Angrist Myers

When they were very young: Almost-threes remember two years ago☆

Abstract Five children who had participated 15–19 times between 6–40 weeks of age in a study of the perception of auditory space returned to the laboratory two years later. The original experimental sequence, which entailed trials in both light and darkness, was carried out along with several additional memory probes. Five control subjects, age, and sex mates who had not previously participated, also experienced the test procedure. Behavior was videotaped and recorded by two observers, and the control and experimental groups were compared on a series of measures. Several measures provide indications that the 2-year-olds remembered what they did in the laboratory two years before; specifically, they retained memory for early action sequences. The findings are of particular interest because a transition from preverbal to verbal functioning marks this 2-year period of development.

Recall of related and unrelated lists by 2-year-olds☆

Abstract Ten boys and 10 girls ages 29–35 months were tested individually on a memory task requiring free recall of two-item lists. Each of the three trials consisted of the randomly ordered presentation of six boxes each containing a pair of objects selected from three categories (food, animals, and utensils). For three of these pairs, the objects belonged to the same conceptual category. The remaining three pairs were formed of unrelated items from the same categories. No sex differences in response were noted nor did performance change systematically over trials. The mean number of correct responses and the mean number of correct pairs was higher for related items. In addition, the children frequently reported the last object they saw first.

Fifty months of memory: A longitudinal study in early childhood.

Three studies were conducted to evaluate long-term memory longitudinally. In Study 1, 10-month-olds (N = 20) were taught to operate a toy in their homes and were tested at home after four months, as were age-matched (14 months) inexperienced controls (N = 20). Experienced infants were more willing to remain in the play situation, relearned faster than controls, and one operated the toy spontaneously. In Study 2, conducted 18 months thereafter, two subgroups (N = 5) of Study 1 groups and an age-matched (32 months) control group (N = 5) were observed in a lab playroom. Only the children with experiences at both 10 months and 14 months operated the toys without being shown. Children with a single 14-month experience made equivalent numbers of toy contacts and successful responses, however, and both groups exceeded controls. In Study 3, conducted 2+ years after Study 2, 36 children played in a novel playroom. Subgroups differed in amount and timing of experience (in Studies 1 and 2); a naive age-matched (60 months) control group (N = 6) was added. Controls took longer to make the toy work than children in the combined experience groups. Only experienced children elected to operate the toys later in the session. Two children verbally recalled part of the 10-month event. The findings are discussed in the light of their relevance to the assessment and description of memory during early childhood.

The effects of size and color cues on the delayed response of very young children

Sixteen children each at 18, 24, 30, and 36 months of age participated in a four-choice delayed reaction task to assess memory for location of a hidden object. On one-third of the trials, only place cues were available; on another third, size cues were added; on the remaining third, color cues were added. All age groups benefited from added visual cues on the test trials, with size cues being particularly facilitating. At the end of the test trials, two additional trials were presented in which the size or color cues were surreptitiously switched so that they were no longer redundant with place cues. Only the oldest children were likely to respond directly to a visual cue when in conflict with place cues. The results support a developmental model suggesting a shift from reliance on place cues. to greater reliance on other associated visual cues, in memory for locating a hidden object.

A Developmental Study of Semantic Effects on Recognition Memory.

Abstract Three experiments evaluated color specificity knowledge and related semantic effects on recognition memory. Experiment I provided the necessary baseline data to show that preschool and college students know the appropriate color of objects. Experiment II revealed semantic effects on recognition of children but not adults. In Experiment III a delay was introduced and adults showed semantic effects as well. The chroma of color-specific and non-color-specific items was remembered relatively well, although chroma recognition for these item types was somewhat different. The semantic effects on very young childrens memory suggest deep level interpretive processing in children younger than those generally showing deliberate deployment of memory strategies.

Long-term memory and retrieval at ages 2, 3, 4☆

Abstract Two experiments are reported examining the contents and accessibility of a subset of the knowledge represented in long-term memory by very young children. In Experiment 1, children aged 2 to 4 were asked in a production task to name items commonly found in particular rooms in a house, and then to verify the appropriate locations of a set of miniature replicas of household items in a dollhouse. In Experiment 2, object context was manipulated to observe if further external context improves or changes production. Children 3 and 4 years old were asked to produce appropriate room items under one of three conditons: either presented no room objects as in the first experiment, or given room objects highly- or less-frequently associated in the first study. Very young children revealed considerable knowledge in this domain, and even at the youngest ages, core defining information was retrieved. It was equally clear, however, that young children know much more than they can produce, that there is noticeable improvement in ability to retrieve information over this age range, and that additional external object context does not necessarily facilitate retrieval from long-term memory.

The effects of unlabeled and labeled picture cues on very young children’s memory for location

Twenty children at each of three age levels were tested in a nine-choice delayed-response task to evaluate their use of picture cues. On some trials, no picture cues were available; on others, unlabeled pictures or labeled pictures were provided. Although performance improved with age, all age groups showed more errorless trials as more cues were provided. The results suggest that children under 3 years can use picture cues, and that age-related increases in verbal label production are not responsible for the developmental improvement.

A Developmental Study of Sequence Structure in Binary Prediction.

Abstract Sixteen groups of 20 Ss each were run individually in a binary prediction situation with each alternative occurring equally often. Four age groups were employed: Ss were either in kindergarten, second, fourth, or sixth grades. For half the Ss at each age level the events occurred in runs of either 1 or 5; the other Ss observed events which occurred in runs of either 4 or 5. The probability of occurrence of the long run (β) was also manipulated: for half the Ss receiving each set of run lengths there were equal numbers of short and long runs (β = .5); for the other Ss β = .2. The results indicated that all groups showed some sensitivity to run length characteristics. However, errors of all types decreased as age increased, and 4–5 sequences were followed more accurately than 1–5 sequences. The results were discussed in terms of their implications for a general model of binary choice behavior.

Stimulus duration effects on secondary reinforcement

Delay of primary reinforcement in training and stimulus duration in extinction were manipulated with kindergarten children as Ss on a push-button task. Each S was exposed to two different potential secondary reinforcers (PSr’s) (red and orange lights) for two different stimulus durations (10 sec. and 1 sec.) in training, and one PSr duration combination (either red-1 sec., red-10 sec., orange-1 sec., or orange-10 sec.) in extinction. The PSr duration in extinction could be the same or different from any PSr-duration combination experienced in training. Control groups received the same schedule of 1 and 10 sec. trials in training, but the PSr was a white light for both durations. Ss responded at a higher rate with a 10-sec. stimulus following a response in extinction than with a 1-sec. stimulus. There were no significant differences between experimental and control groups. Results were interpreted in the light of magnitude of reinforcement, and the discrimination hypothesis.

A case study of early event representation development

Abstract The purpose of this study was to describe the emergence and early development of event knowledge in a very young child. The results of two methodologies—a diary study and an experiment-were combined in a case study of one toddlers memory for making cookies. Questions about contextual control of event memory, combination of event experiences in memory, and the relationship between event representation and object category representation were addressed. The data indicated that development of an event representation for making cookies was rapid. This representation permitted memory retrieval even outside of the event situation, organized different event experiences, and allowed new object category definition, yet was itself largely defined by object categories.