Towards personalized electroceutical therapy: electrophysiological investigations in a preclinical model of ischemic lesion

Stroke is one of the main causes of long-term disability worldwide. Recently, an activity-dependent intracortical microstimulation technique demonstrated the capability of closed loop approaches to better entrain network activity with respect to standard random stimulation. This was demonstrated at the pre-clinical level, in rodent models following an ischemic lesion in the primary motor cortex. At the clinical level, stimulation-based therapy still relies on standardized protocols with not so convincing results. A possible explanation for these inconsistencies is the lack of tailored, personalized stimulation protocols. In this study, we aimed at investigating the changes in the electrophysiological activity occurring in a preclinical model of focal lesion and the subsequent effect of a personalized, open-loop stimulation therapy. We adopted anesthetized Long-Evans rats undergoing a focal ischemic injury in the caudal forelimb area (i.e., CFA). Microelectrode arrays were inserted in the ipsilesional rostral forelimb area (i.e., RFA) to record spike activity and in the somatosensory cortex (i.e., S1) also to deliver intracortical microstimulation. We found that the ischemic injury in CFA led to an overall decrease of the spiking activity both in RFA and S1. A neurostimulation treatment with tailored open loop microstimulation tended to increase the firing activity in both RFA and S1. Further studies will be necessary to confirm these preliminary findings, which can lead to design novel electroceutical therapies for stroke rehabilitation.