Brain and Behavior

Abstract

Cognitive neuroscience is a new interdisciplinary approach to an understanding of mind-brain relations that combines cognitive psychology and neurological sciences. These two fields of study seek answers to many of the same questions and have methodological and conceptual contributions to offer one another. Further envisioned is the possibility of going beyond the of mutual contributions towards developing a unified, interdisciplinary science of human nature. The physiological basis for the storage of information in the nervous system-or the formation of memory-is an important problem that requires an interdisciplinary effort. One theoretical framework of cognitive psychology, the consolidation model for memory, states that information storage involves a sequential process, which begins with a short-term sensory store. The shortest of memory stores is the sensory register and is called the iconic store. Here sensory items are perceived and subsequent attention to material in this iconic store may lead to literal copy of the input and transfer to short-term store. Information can be maintained for only a second or two; and if it is not transferred to short-term stores, there is much information loss. Short-term memory, the next stage of processing, has a time duration measured in minutes and seems to have capacity limitations as well. Transfer of shortterm information to long-term stores may be accomplished through rehearsal, and long-term memory may last a lifetime. The transitions from one store to the next probably require neurochemical processes. Recent developments of this consolidation model suggest that shortterm memory may be the active state of long-term memory (Posner 1977). In this more unitary view of memory processes, any stimulus can have multiple representations including visual, tactile, phonemic, or semantic systems. Minimizing the distinction between short-term and long-term stores, this hypothesis emphasizes the existence of levels of human memory where depth of processing may play an important role. In this theoretical framework, preliminary analysis includes physical features as edges, angles, brightness, hue, pitch, and loudness. Later stages consist of recognizing patterns and matching these against stored patterns. A word, for example, is immediately processed phonemically and morphemically, only to trigger further semantic associations based on the subjects' experiences. This enrichment and elaboration of the word allow the subject to extract meaning, and of course, this depth of processing approach is not restricted to verbal material. A recent clinical experience with an elderly patient illustrates the disruption of the ability to choose and maintain an appropriate memory level. This man had great difficulties organizing the trivialities of his daily life. Formerly automatic events, such as putting on both shoes and tying them, or finding his way to his office, had become insurmountable chores. Forgetting the time and often his exact location, he frequently wandered to distant corners of the hospital. When confronted with the apparent aimlessness of his direction, he responded with a gruffness and indignation that befitted his former brilliance. Throughout his long life he had been the creator of a number of powerful scientific theories. His philosophical treatises had also gained him worldwide recognition; yet, at moments he could not remember the time of year and had only a vague glimmer of intuition regarding the reasons for his hospitalization. To the ordinary medical examiner he appeared hopelessly demented, but further analysis revealed several tantalizing possibilities. By establishing contexts with linguistic cues he verbally reconstructed past episodes about his life. For example, the mere mention of a former colleague prompted an emotive and accurate