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Transcranial Direct Current Stimulation tDCS for Memory Enhancement
Published on: September 18, 2021
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Real-time activation of central cholinergic circuits during recognition memory
Sonia Bonnì1, Viviana Ponzo1, Francesco Di Lorenzo1
1Non-Invasive Brain Stimulation Unit, Neurologia Clinica e Comportamentale, Fondazione Santa Lucia IRCCS, Via Ardeatina 306, 00179, Rome, Italy.
The European Journal of Neuroscience
|April 27, 2017
Summary
Short latency afferent inhibition (SAI), a marker of brain acetylcholine activity, increases during memory retrieval. This finding suggests SAI modulation by memory tasks, offering a new neurophysiological marker for cognitive processes.
Area of Science:
- Neuroscience
- Cognitive Science
- Neurophysiology
Background:
- Short latency afferent inhibition (SAI) is a transcranial magnetic stimulation (TMS) protocol reflecting central cholinergic activity.
- Acetylcholine plays a key role in memory processes.
- The impact of memory tasks on SAI has not been previously studied.
Purpose of the Study:
- To investigate the modulation of SAI circuits during a recognition memory task (RMT).
- To determine if SAI can serve as a neurophysiological marker for memory-related cholinergic activity.
Main Methods:
- Healthy subjects performed a computerized non-verbal RMT involving face recognition.
- SAI was measured during baseline, encoding, consolidation, retrieval, and post-task phases.
- A control task involving visual feature judgment was used for comparison.
Main Results:
- SAI significantly increased during the retrieval phase of the RMT compared to baseline.
- No significant changes in SAI were observed during the control task.
- These results indicate that SAI is modulated by active memory processes.
Conclusions:
- Ongoing memory processes can modulate SAI.
- SAI shows potential as a neurophysiological marker of central cholinergic activity during memory tasks.
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