Short Term and Long Term Memory Processes: A Functional Model of Fronto-Temporal Relationships

摘要

Monkeys trained by the direct method in a six-second spatial delayed response task manifested a return to pre-operative performance levels after being subjected to bilateral orbital lesions. In contrast, animals trained by the indirect method and subjected to the same surgery are incapable of performing at pre-operative levels. This differential deficit, as a function of training, was not seen in a third group of animals trained by both methods; rather, these animals manifested rapid recovery of performance capability when tested by both the direct and indirect methods. Bilateral amygdalectomy, after the performance stabilized following the orbital surgery, had no effect in any of the three groups. These data, in conjunction with previous findings concerning bilateral principal sulcus lesions, are interpreted in context of the functional organization of the prefrontal lobe, i.e. the dorsolateral surface is concerned with short-term processes as defined by the direct method delayed response task, and the orbital surface is concerned with long-term processes as defined by the indirect method delayed response task. A model of neural organization is presented based on primary foci, secondary foci, and redundancy areas. (Author)