Memory is a multifaceted process through which living beings can actively retain information acquired through experience for a short- or long-term. In the classical view, memory is conceived as the result of mental representations that arise from the activity of specific cortical areas, among which the hippocampus is the most studied structure precisely because of its role in various types of memory. This classical view is being challenged by evidence that showed the role of different subcortical and peripheral areas in memory formation. Indeed, the emerging perspectives in cognitive neuroscience suggest that human cognitive abilities are mediated by the relationship that our body as a whole generates with the external world, through the activation of sensory and motor systems. This perspective conceives cognition as a function evolved from brain-body interactions and the body as a central agent in the regulation of cognitive functions that can influence brain activity and affect behaviour, be it an action, a thought or a memory.
Touch is a crucial sense for animals that allows to explore and interact with the environment since birth. Interestingly, evidence shows that the somatosensory system might actively modulate memory functions; indeed, tactile stimulation has been shown to elicit hippocampal responses – through the thalamus and the somatosensory cortex (S1) – increasing S1-hippocampus rhythm phase synchronization, stimulating memory-related plasticity in the hippocampus, improving memory performance, and augmenting the survival and differentiation of hippocampal cells in adulthood.
Additionally, transcutaneous electric stimulation (TENS), which is known to activate the somatosensory tactile system, has been shown to modulate the activity of cortical and subcortical brain regions, change neurotransmitters release, modulate neural plasticity pathways and potentiate memory (Fig. 1).
Although these interesting set of evidence, the role of touch in the mechanisms related to memory formation has never been systematically investigated.
Our hypothesis is that stimulation of somatosensory tactile fibres (Fig. 2) from the peripheral nervous system might elicit a neural entrainment and neuromodulatory pathways activation that if applied in specific temporal windows can potentiate memory functions and related molecular changes through mechanisms of heterosynaptic plasticity.
Figure 1. TENS hypothesized mechanism of action on cognitive functions (Fiorentini et al., 2025). The figure shows the different types of peripheral nerves stimulated through TENS, which have been used to modulate cognition, and the neuromodulatory pathways that might be recruited.
Figure 2. Main experimental approaches that are being developed in the lab for studying the potential of tactile stimulation for memory enhancement.
References
Fiorentini, G., Massè, E., Ficarella, S., Torromino, G.# (2025). Peripheral transcutaneous electrical stimulation to improve cognition: a review of the main effects in healthy humans and in mildly cognitively impaired patient populations. Progress in Neuropsychopharmacology & Biological Psychiatry, 111290.
Torromino, G.*, Loffredo, V., Cavezza, D., Sonsini, G., Esposito, F., Crevenna, A. H., Gioffrè, M., De Risi, M., Treves, A., Griguoli, M. & De Leonibus, E. (2022). Thalamo-hippocampal pathway regulates incidental memory capacity in mice. Nature Communications, 13(1), 4194.
Torromino, G., Maggi, A., & De Leonibus, E. (2021). Estrogen-dependent hippocampal wiring as a risk factor for age-related dementia in women. Progress in Neurobiology, 197, 101895.