tES Effects on Associative Memory Performance
- Conditions
- Alzheimer DiseaseHealthyMild Cognitive Impairment
- Interventions
- Device: real anodal transcranial direct current stimulationDevice: real transcranial alternating current stimulationDevice: sham transcranial electric current stimulation
- Registration Number
- NCT03351452
- Lead Sponsor
- University of Bern
- Brief Summary
Previous studies showed that transcranial electric stimulation (tES) applied over the prefrontal cortex improves cognitive performance in healthy elderly adults as well as in patients suffering from mild cognitive impairment or early Alzheimer's disease. Therefore, tES methods might be a useful intervention tool for patients suffering from memory impairment in early terms of the disease.
The present study aims at establishing a connection between the stimulation-induced changes on associative memory performance and its underlying neurophysiological parameters. tES effects and their underlying mechanisms will be compared between healthy elderly controls and clinical study populations receiving either real or sham tES over the left ventrolateral prefrontal cortex during an associative memory task.
- Detailed Description
Not available
Recruitment & Eligibility
- Status
- COMPLETED
- Sex
- All
- Target Recruitment
- 28
- Written informed consent
- Non-smokers
- Right-handedness
- Native German speakers or comparable level of fluency
- Normal or corrected-to-normal vision
- Neurological or psychiatric condition (other than diagnosed cognitive impairment)
- Past head injuries
- Magnetizable implants
- History of seizures
- Current or life-time alcohol or drug abuse
- Skin diseases
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- CROSSOVER
- Arm && Interventions
Group Intervention Description Real tDCS real anodal transcranial direct current stimulation 20 min of 2 mA real anodal transcranial direct current stimulation applied via 5x7 cm rubber electrode over the VLPFC (current density: 0.057 mA/cm2) and cathodal 10x10 rubber electrode over supraorbital region (current density: 0.02 mA/cm2). Additional ramp-up and ramp-down phase of 15 s at the beginning and the end of stimulation. Real tACS real transcranial alternating current stimulation 20 min of 2 mA real transcranial alternating current stimulation in theta frequency applied via 5x7 cm and 10x10 cm rubber electrodes over the VLPFC (current density: 0.057 mA/cm2) and supraorbital region (current density: 0.02 mA/cm2). Additional ramp-up and ramp-down phase of 15 s at the beginning and the end of stimulation. Sham tES sham transcranial electric current stimulation 30 s of 2 mA sham transcranial electric current stimulation applied via 5x7 cm and 10x10 cm rubber electrodes over the VLPFC (current density: 0.057 mA/cm2) and supraorbital region (current density: 0.02 mA/cm2). Additional ramp-up and ramp-down phase at beginning and end of stimulation lasting for 15 s. Electrodes remain attached to the participant's head for the duration of the encoding phase of the memory task.
- Primary Outcome Measures
Name Time Method Performance on immediate cued recall task 20 min Number of correct responses on retrieval task of previously learned associative memory items
Performance on delayed cued recall task 24 hours Number of correct responses on retrieval task of previously learned associative memory items
- Secondary Outcome Measures
Name Time Method task-dependent BOLD activity 20 min Measured with functional magnetic resonance imaging (fMRI)
resting-state BOLD activity 10 min Measured with functional magnetic resonance imaging (fMRI)
Trial Locations
- Locations (1)
University Hospital of Old Age Psychiatry and Psychotherapy
🇨🇭Bern, Switzerland
University Hospital of Old Age Psychiatry and Psychotherapy🇨🇭Bern, Switzerland