Transcranial direct current stimulation of the right temporoparietal junction facilitates hippocampal spatial learning in Alzheimer's disease and mild cognitive impairment

S Philippen; A Hanert; R Schönfeld; O Granert; R Yilmaz; U Jensen-Kondering; M Splittgerber; V Moliadze; M Siniatchkin; D Berg; T Bartsch

doi:10.1016/j.clinph.2023.11.003

Transcranial direct current stimulation of the right temporoparietal junction facilitates hippocampal spatial learning in Alzheimer's disease and mild cognitive impairment

Clin Neurophysiol. 2024 Jan:157:48-60. doi: 10.1016/j.clinph.2023.11.003. Epub 2023 Nov 15.

Authors

S Philippen¹, A Hanert¹, R Schönfeld², O Granert¹, R Yilmaz³, U Jensen-Kondering⁴, M Splittgerber⁵, V Moliadze⁵, M Siniatchkin⁶, D Berg¹, T Bartsch⁷

Affiliations

¹ Dept. of Neurology, Memory Disorder and Plasticity Group, University Hospital Schleswig-Holstein, Kiel, Germany.
² Psychology Department, Halle University, Germany.
³ Dept. of Neurology, University of Ankara, Medical School, Ankara, Turkey.
⁴ Dept. of Radiology and Neuroradiology, University Hospital Schleswig-Holstein, Kiel, Germany; Dept. of Neuroradiology, University Hospital Schleswig-Holstein, Lübeck, Germany.
⁵ Institute of Medical Psychology and Medical Sociology, University Medical Center Schleswig-Holstein, Kiel University, Germany.
⁶ Institute of Medical Psychology and Medical Sociology, University Medical Center Schleswig-Holstein, Kiel University, Germany; Clinic for Child and Adolescent Psychiatry and Psychotherapy, Medical Center Bethel, University Clinics OWL, Bielefeld University, Germany.
⁷ Dept. of Neurology, Memory Disorder and Plasticity Group, University Hospital Schleswig-Holstein, Kiel, Germany. Electronic address: [email protected].

PMID: 38056370
DOI: 10.1016/j.clinph.2023.11.003

Abstract

Objective: Spatial memory deficits are an early symptom in Alzheimer's disease (AD), reflecting the neurodegenerative processes in the neuronal navigation network such as in hippocampal and parietal cortical areas. As no effective treatment options are available, neuromodulatory interventions are increasingly evaluated. Against this backdrop, we investigated the neuromodulatory effect of anodal transcranial direct current stimulation (tDCS) on hippocampal place learning in patients with AD or mild cognitive impairment (MCI).

Methods: In this randomized, double-blind, sham-controlled study with a cross-over design anodal tDCS of the right temporoparietal junction (2 mA for 20 min) was applied to 20 patients diagnosed with AD or MCI and in 22 healthy controls while they performed a virtual navigation paradigm testing hippocampal place learning.

Results: We show an improved recall performance of hippocampal place learning after anodal tDCS in the patient group compared to sham stimulation but not in the control group.

Conclusions: These results suggest that tDCS can facilitate spatial memory consolidation via stimulating the parietal-hippocampal navigation network in AD and MCI patients.

Significance: Our findings suggest that tDCS of the temporoparietal junction may restore spatial navigation and memory deficits in patients with AD and MCI.

Keywords: Alzheimer’s disease; Hippocampal place cells; Navigation network; Spatial memory; Transcranial direct current stimulation.

Publication types

Randomized Controlled Trial

MeSH terms

Alzheimer Disease* / therapy
Cognitive Dysfunction* / therapy
Double-Blind Method
Hippocampus
Humans
Memory Disorders
Spatial Learning
Transcranial Direct Current Stimulation* / methods