Cortical adapation to orofacial somatosensory stimulation in children and adults
The integrity of the cerebral cortex can be assessed by measuring its responsiveness to repetitive sensory and motor stimulation. This neurophysiologic feature is known as neural adaptation, and is thought to enhance learning and detection of environmental stimuli. The adaptation of hemodynamic responses to motor and sensory experiences in hand and face are of particular interest—as these are structures most commonly used in human communication—and proper delivery of oxy-hemoglobin to primary motor (M1) and somatosensory (S1) cortices is essential for functional cortical activation.
The goal of the current research project is to examine the hemodynamic differences between hand and face cortical representations during motor and passive somatosensory conditions in children and adults, as measured with functional near-infrared spectroscopy (fNIRS). The recorded data will be used to map developmental changes in patterns of cortical adaptation and hemodynamic responses in an effort to provide a longitudinal picture of normal physiologic connectivity and function, as well as create a computational model of cortical adaptation for future neurodiagnostic and neurotherapeutic applications in disordered populations across the lifespan.
Somatosensory and Motor Function in Individuals with Cerebral Stroke Following Patterned Pneumocutaneous Stimulation
This ongoing study involves approximately 30 adult participants diagnosed with chronic, single hemisphere cortical stroke, and is intended to expand our understanding of the effects of sensory stimulation on sensorimotor impairment in adults who have survived cortical infarct. This is a collaborative project involving researchers and clinicians from UNL and Madonna Rehabilitation Hospital. This study will focus on how neural adaptation induced by sensory training affects sensory and fine motor performance in patients with residual hemiparesis.
Neuroimaging: Velocity Encoding of Saltatory Somatosensory Inputs in Human Brain
Animal and human models of brain plasticity have shown that the development of functional motor tasks can be facilitated by repetitive sensory stimulation. This development model can be used for the rehabilitation of brain-damaged patients to regain hand movement and speech ability. Published studies of motor tasks have been limited to neurotypical adults using visual and electric stimulation. The aim of the proposed study is to map the relation between saltatory somatosensory (touch pressure) stimulation of the hand and face and activation of primary and secondary somatosensory cortices in neurotypical adults. Saltatory stimulation in this experiment involves the presentation of pneumatic touch pulses which essentially "jump" from one node to another node on the surface of the skin at traverse velocities ranging from very slow to very fast on the surface of the hand. Brain activity will be recorded by placing the participant in the bore of a magnetic resonance imaging (MRI) scanner in order to sample the evoke hemodynamic response to the somatosensory stimulation. Results of this study are expected to lead to the development of innovative neurotherapeutics in adult stroke.
Adaptation of the cSEP Following Pneumatic Stimulation of the Face in Adults*
This study utilized a 4-channel electroencephalography (EEG) recording montage to characterize the adaptation of cortical somatosensory evoked potentials (cSEP) in response to servo-controlled pneumotactile (touch) inputs to the lower face. Stimuli were delivered to 20 healthy adults using a custom built device called the TAC-Cell. This EEG measure of cortical and subcortical adaptation in the neurotypical brain will serve as a referent for future evaluations of disruption associated with acquired (e.g., stroke, TBI) and neurodevelopmental disorders (e.g., ASD).