Alpha oscillations (7-13 Hz) have been historically considered to shape temporal sampling processes in the visual modality, with faster alpha frequencies linked to finer temporal resolution. However, evidence is mostly correlational, and findings are not always replicated. Here, we investigated the role of alpha oscillations in temporal sampling using transcranial alternating current stimulation (tACS) and electroencephalography (EEG). Over three consecutive blocks, bilateral high-definition tACS was applied over extra-striate visual areas including V5/MT at either the individual alpha frequency (IAF), IAF+2, or IAF-2 Hz while participants performed a two flash fusion task. In line with previous findings, baseline resting-state IAF correlated with temporal segregation accuracy, with higher IAF predicting better segregation ability. Importantly, stimulation at IAF+2 Hz improved temporal segregation accuracy, whereas IAF-2 Hz decreased performance. This effect was specific for stimuli in the right hemifield, highlighting important hemispheric differences in alpha-mediated visual temporal sampling. Following stimulation, EEG data revealed no shift in the IAF and a decrease of alpha power independently from stimulation condition. Nonetheless, specifically for the IAF+2 stimulation, we observed a modulation of the aperiodic exponent of the power spectrum, indicating possible changes in cortical excitability as a short-term plasticity mechanism that persists beyond online tACS effects. Taken together, these results corroborate the role of alpha oscillations in defining temporal sampling processes and add novel evidence on the neurophysiological effects of tACS.

Parkinson’s disease (PD) neuropathology is marked by the selective loss of dopaminergic neurons in the substantia nigra pars compacta, accompanied by the widespread involvement of central and peripheral structures. Brain-derived neurotrophic factor (BDNF), a neurotrophin crucial for the survival of dopaminergic neurons, plays a pivotal role in neuronal and glial development, neuroprotection, and the modulation of synaptic plasticity. Repetitive transcranial magnetic stimulation (rTMS), a non-invasive technique, enhances neurotransmitter release, trans-synaptic efficacy, signaling pathways, gene transcription, neuroplasticity, and neurotrophism. Evidence supports that high-frequency rTMS increases BDNF expression and improves task-specific cognitive deficits in PD patients. This article outlines a detailed protocol to investigate whether rTMS targeting the dorsolateral prefrontal cortex bilaterally induces changes in plasma BDNF levels, the plasma-derived exosomal BDNF concentration, and executive functions in individuals with PD. Identifying non-invasive interventions that effectively modulate the neurobiological mechanisms underlying cognitive and behavioral functions is critical for addressing cognitive impairments and mitigating disease progression in the PD population. This study aims to advance translational research by identifying biomarkers and developing therapeutic strategies for future applications in neurodegenerative diseases.

Background/Objectives: Chronic psychomotor and cognitive slowing after stroke can persist despite standard rehabilitation, especially in young adults with subcortical injuries. Innovative, integrated interventions are crucial for patients who have reached a plateau in their rehabilitation. We present a case of a 41-year-old male with chronic psychomotor and cognitive slowing following a left lenticulostriate infarction (NIHSS score = 5 at onset), who had plateaued after conventional rehabilitation. Methods: Over 4 weeks the patient underwent 20 sessions of a multimodal approach including high-frequency repetitive transcranial magnetic resonance stimulation over the supplementary motor area and bilateral temporo-parietal junctions and simultaneous computerized cognitive training targeting attention and executive function. Both motor and cognitive assessments, along with quantitative EEG (qEEG) evaluations, were conducted before and after the treatment. Results: At the end of treatment, the patient showed significant clinical improvement: speed and coordination in upper extremities (Finger Tapping Test) increased by 66% (dominant hand) and 74% (non-dominant hand), while finger dexterity (Nine-Hole Peg Test) increased by 25% (dominant hand) and 19% (non-dominant hand). Cognitive scores improved in alertness (58%), visual exploration (25%), and flexibility (24%), while divided attention remained stable. qEEG investigation showed increases in alpha (79%), gamma (33%), and beta (10%) power, with topographic shifts in the stimulated regions. Conclusions: These findings highlight the feasibility of combining targeted rTMS and cognitive training to enhance neuroplasticity in the chronic phase of stroke. Clinical recovery was accompanied by normalized cortical rhythms, suggesting qEEG biomarkers may be useful for tracking treatment response. Multimodal precision neurorehabilitation may offer a path forward for patients with persistent cognitive–motor deficits post-stroke.