Memory Development in Children: Implications for Children as Witnesses in Situations of Possible Abuse. (Practice & Theory)

Article excerpt

For several decades, Piaget's (1954) theory of cognitive development has dominated the literature on children's thinking. His astute observations provided insight for a generation of educators and developmental experts into the qualitative changes that are associated with cognitive maturation. More recently, live viewing of the inner workings of the brain has provided an unprecedented opportunity to watch and measure activities such as synaptic development and functioning (Berk, 1994). Combining the knowledge from cognitive development theory with information from brain development research greatly increases the capability to understand how memory develops in infants and children. This information has significant implications for counselors interviewing children who may have been sexually abused. Accordingly, this article discusses the physiological constructs of memory development as they relate to a child's ability to recall accurately detailed accounts of alleged abuse. On the basis of this information, counselors are given suggestions for increasing the reliability of responses of children who have been abused.

MEMORY DEVELOPMENT

Normal memory function involves processing the incoming information by encoding, storing, and retrieval. Because information is encoded and stored according to existing schema, retrieval is enhanced when the event is related to preexisting knowledge and is relevant to existing beliefs (Piaget, 1954). Memory retrieval is also facilitated by cues (e.g., physical environment) similar to those present at the time of encoding. For example, students given tests in the same classroom environment in which the information was presented perform significantly better than students who take the tests in environments that are much different from the original classroom (Farnham-Diggory, 1992). However, memories of individuals who have been exposed to extreme trauma may not follow normal processes (Bremmer, 1999).

It is now widely accepted that there is no single place for memory storage in the brain (Bremmer, Krystal, Charney, & Southwick, 1996). Memory is arbitrated by several brain regions, including the hippocampus (Schacter & Tulving, 1994). Memories are first stored in the hippocampus, then reorganized and placed in other brain areas. For example, visual information is stored in the occipital cortex. At the time of retrieval, elements from the various neocortical areas are reassembled by the hippocampus. Bremmer et al. (1996) found that adult survivors of childhood physical and sexual abuse had 12% lower memory volume in the left hippocampal brain area than did comparison subjects, which suggests a deficit in explicit memory ability. Because stress-induced glucocorticoids such as cortisol seem to be toxic to the hippocampus, there is reason to believe that stress-induced memory deficit is associated with damage to this region of the brain (Bremmer, 1999). Given this information, it is clear that an awareness of the mechanisms of memory development is helpful for understanding problems with the recall of childhood memories.

Infancy

Infant memory studies suggest that newborns can recognize previously seen or heard stimuli (Karl, 1990). Recall memory is detected at 6 or 7 months. However, specific experiences from infancy typically cannot be recalled in adulthood because of storage and retrieval problems often referred to as "infantile amnesia" (Neath, 1997). Storage and retrieval failure may be best understood using information-processing theory. Information from the environment enters the sensory register (visual, auditory, tactile, olfactory, and gustatory) where the literal image is held for less than one second. The information then moves to short-term memory (STM), which is also known as "working memory." STM is limited by time and capacity, storing approximately five to nine pieces of information for 30 seconds or less. Memory strategies such as rehearsal, coding, and chunking (pieces of information grouped together to make them more easily recalled) must transform the information into something meaningful in order to transfer the information into long-term memory (LTM). …