Processing time and space components of semantic memory: A study of frontal-lobe-related impairments

Eleven patients with frontal-lobe damage and 12 control subjects were teste d on temporal and spatial script-generation tasks and on two tests that req uired organization of semantic knowledge in the appropriate spatial or temp oral order. Patients displayed typical perseverative errors in temporal scr ipts, but produced sequence errors regardless of the nature of the informat ion. Moreover, the semantic structure of the patient's scripts was largely composed of idiosyncrasies and a low frequency of major actions for the spa tial scripts. Results are discussed within Shallice's and Grafman's theoret ical frameworks. (C) 1999 Academic Press.