The role of executive functions in long-term memory: case report

Abstract

The role of executive functions in long-term memory has been studied. We describe a single-case study, consisting of a 45-year-old male patient, hospitalized for right frontal stroke. After the stroke, the patient had memory alterations in everyday activities. However, performance in short-term memory tests was not significantly altered. Long-term memory assessments included pre- and post-stroke episodic, semantic, and procedural memories. Specific skills involved in the acquisition of new learning (auditory-verbal and visual reproduction) were also evaluated, as well as executive functions. The results evidence that short-term memory was not affected. Regarding long-term memory, significant differences were observed between pre- and post-stroke knowledge, the former being better preserved, which reveals anterograde amnesia. Pre- stroke long-term memory was also affected, but only with respect to episodic knowledge, with semantic and procedural memories preserved (episodic retrograde amnesia). Executive functions were altered as well, which could have been a factor affecting the acquisition and consolidation of new learning, despite the fact that short-term memory was not significantly altered. Therefore, executive functions might be a determinant factor in the acquisition of new learning, regardless of short- term memory processes, at least partially. According to the results of the present study, alterations in these functions might lead to anterograde amnesia. This entails the need to evaluate executive functions as an intrinsic part of memory evaluation.