No Object–Location Memory Improvement through Focal Transcranial Direct Current Stimulation over the Right Temporoparietal Cortex

• Published in: Life (Basel, Switzerland) Vol. 14; no. 5; p. 539
• Main Authors: Fromm, Anna Elisabeth, Grittner, Ulrike, Brodt, Svenja, Flöel, Agnes, Antonenko, Daria
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 01.05.2024
• Subjects: Animal cognition; Between-subjects design; Brain; Brain research; Cognitive ability; cognitive neuroscience; current flow modeling; Direct current; Electric fields; Electrical stimulation of the brain; ESB; focal transcranial direct current stimulation; Health aspects; Learning; Magnetic brain stimulation; Memory; Methods; Neuropsychology; object–location memory; Recall; Stimulation; Training; Transcranial magnetic stimulation; Verbal learning; Germany; current flow modeling; focal transcranial direct current stimulation; cognitive neuroscience; object–location memory
• ISSN: 2075-1729; 2075-1729
• DOI: 10.3390/life14050539

Remembering objects and their associated location (object–location memory; OLM), is a fundamental cognitive function, mediated by cortical and subcortical brain regions. Previously, the combination of OLM training and transcranial direct current stimulation (tDCS) suggested beneficial effects, but the evidence remains heterogeneous. Here, we applied focal tDCS over the right temporoparietal cortex in 52 participants during a two-day OLM training, with anodal tDCS (2 mA, 20 min) or sham (40 s) on the first day. The focal stimulation did not enhance OLM performance on either training day (stimulation effect: −0.09, 95%CI: [−0.19; 0.02], p = 0.08). Higher electric field magnitudes in the target region were not associated with individual performance benefits. Participants with content-related learning strategies showed slightly superior performance compared to participants with position-related strategies. Additionally, training gains were associated with individual verbal learning skills. Consequently, the lack of behavioral benefits through focal tDCS might be due to the involvement of different cognitive processes and brain regions, reflected by participant’s learning strategies. Future studies should evaluate whether other brain regions or memory-relevant networks may be involved in the modulation of object–location associations, investigating other target regions, and further exploring individualized stimulation parameters.