Semantic Relations and Repetition of Items Enhance the Free Recall of Words by Multiple Sclerosis Patients

Abstract

We compared 25 patients with multiple sclerosis (MS) and 24 normal controls on a test of free recall of words. Some lists contained words that were all unrelated, while in others the intermediary words were semantically related. In another set, the mid-list words were repeated across the lists, or, in addition to the repetition, were semantically associated. Immediate recall was assessed using these lists. Delayed recall was assessed using different lists (delay-unrelated and delay-related) after distractor tasks. Recency was not affected in MS patients, but the primacy effect was lower than in controls, this effect being interpreted as due to a deficiency in articulatory rehearsal. The delay interval after each list abolished recency in both groups and resulted in impaired recall in MS patients. However the patients, like the controls, benefited from semantic relations in the middle of the lists and from spaced repetition of words across the lists, in either immediate and delayed recall. The enhancing effects of word relatedness and of spaced repetition are seen as being due to automatic processes preserved in MS patients.