Abstract
Cognitive reserve (CR) is the capacity to cope with cognitive impairments due to brain damage by neurological disease. CR is increased by intellectually enriching activities, such as education, occupation, and leisure. After brain tumor resection, patients show working memory impairment because of damage to fronto-parietal networks, such as the superior longitudinal fascicle (SLF). To date, whether occupational experience represented as CR impacts postoperative working memory impairment in patients with frontal lobe tumors remains unknown. We hypothesized that occupational experience predicted postoperative working memory and that higher damage in the SLF was associated with poorer working memory. We enrolled 27 patients who had undergone tumor resection. Patient's occupational experience was estimated using an occupational complexity index based on a dictionary of occupational titles. Working memory was measured using verbal and spatial working memory tasks. Our results showed that patients who had engaged in more complex occupations showed higher performance of postoperative working memory, which supported the previous CR hypothesis. In conclusion, CR has protective effects against working memory impairment in patients with frontal lobe tumors. CR measures, such as occupational experience, will help more accurately predict the severity of working memory deficits and the likelihood of recovery in the postoperative period.
Visuo-spatial working memory deficit in patients with frontal lobe lesion. Investigation using a maze test.
