title: Effects of non-invasive brain stimulation on associative memory.
abstract: Associative memory refers to remembering the association between two items, such as a face and a name. It is a crucial part of daily life, but it is also one of the first aspects of memory performance that is impacted by aging and by Alzheimer's disease. Evidence suggests that transcranial direct current stimulation (tDCS) can improve memory performance, but few tDCS studies have investigated its impact on associative memory. In addition, no prior study of the effects of tDCS on memory performance has systematically evaluated the impact of tDCS on different types of memory assessments, such as recognition and recall tests. In this study, we measured the effects of tDCS on associative memory performance in healthy adults, using both recognition and recall tests. Participants studied face-name pairs while receiving either active (30 min, 2 mA) or sham (30 min, 0.1 mA) stimulation with the anode placed at F9 and the cathode placed on the contralateral upper arm. Participants in the active stimulation group performed significantly better on the recall test than participants in the sham group, recalling 50% more names, on average, and making fewer recall errors. However, the two groups did not differ significantly in terms of their performance on the recognition memory test. This investigation provides evidence that stimulation at the time of study improves associative memory encoding, but that this memory benefit is evident only under certain retrieval conditions.
authors.affiliation: Cognitive Science and Applications, Sandia National Laboratories, P.O. Box 5800, Albuquerque, NM 87185-1327, United States. Electronic address: lematze@sandia.gov.
authors.forename: Laura E
authors.initials: LE
authors.lastname: Matzen
authors.affiliation: Cognitive Science and Applications, Sandia National Laboratories, P.O. Box 5800, Albuquerque, NM 87185-1327, United States; University of New Mexico, United States.
authors.forename: Michael C
authors.initials: MC
authors.lastname: Trumbo
authors.affiliation: University of Illinois at Chicago, United States.
authors.forename: Ryan C
authors.initials: RC
authors.lastname: Leach
authors.affiliation: University of Illinois at Chicago, United States.
authors.forename: Eric D
authors.initials: ED
authors.lastname: Leshikar
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D001245:Association Learning / Q000502:physiology; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D011939:Mental Recall / Q000502:physiology*; D008875:Middle Aged; D009275:Names; D009483:Neuropsychological Tests; D010100:Oxygen / Q000097:blood; D017397:Prefrontal Cortex / Q000098:blood supply / Q000502:physiology*; D021641:Recognition, Psychology / Q000502:physiology*; D012737:Sex Factors; D065908:Transcranial Direct Current Stimulation; D055815:Young Adult
chemical_list: D010100:Oxygen
keywords: Associative memory; Recall; Recognition; tDCS