Improved proper name recall in aging after electrical stimulation of the anterior temporal lobes

Abstract

Evidence from neuroimaging and neuropsychology suggests that portions of the anterior temporal lobes (ATLs) play a critical role in proper name retrieval. We previously found that anodal transcranial direct current stimulation (tDCS) to the ATLs improved retrieval of proper names in young adults (Ross et al., 2010). Here we extend that finding to older adults who tend to experience greater proper-naming deficits than young adults. The task was to look at pictures of famous faces or landmarks and verbally recall the associated proper name. Our results show a numerical improvement in face naming after left or right ATL stimulation, but a statistically significant effect only after left-lateralized stimulation. The magnitude of the enhancing effect was similar in older and younger adults but the lateralization of the effect differed depending on age. The implications of these findings for the use of tDCS as tool for rehabilitation of age-related loss of name recall are discussed.

Keywords: brain stimulation; electrophysiology; memory; person identity; semantic; social cognition; tDCS; temporal poles.

Figure 1

Average percent accuracy for correct trials with long response times in the face condition and place condition (older adults only).

Figure 2

Left panel: Face naming accuracy difference scores (%) for ATL stimulation versus sham condition for each subject group. Right panel: Place naming accuracy difference scores (%) for ATL stimulation versus sham condition for each subject group.