Mario I. Romero-Ortega

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—A biocompatible neural microprobe constructed using well-established SU-8 microfabrication techniques is described that was designed to record fiber spike signals from regenerated axons within peripheral nerves. These microprobes features bipolar longitudinal gold electrodes recessed below the surface within " grooves " designed to guide the growth of(More)
The integration of newborn neurons into functional neuronal networks requires migration of cells to their final position in the developing brain, the growth and arborization of neuronal processes and the formation of synaptic contacts with other neurons. A central player among the signals that coordinate this complex sequence of differentiation events is(More)
Cumulative evidence from both humans and animals suggests that the anterior cingulate cortex (ACC) is important for pain-related perception, and thus a likely target for pain relief therapy. However, use of existing electrode based ACC stimulation has not significantly reduced pain, at least in part due to the lack of specificity and likely co-activation of(More)
Regenerative peripheral nerve interfaces have been proposed as viable alternatives for the natural control of robotic prosthetic devices. However, sensory and motor axons at the neural interface are of mixed sub-modality types, which difficult the specific recording from motor axons and the eliciting of precise sensory modalities through selective(More)
In the injured adult nervous system, re-establishment of growth-promoting molecular gradients is known to entice and guide nerve repair. However, incorporation of three-dimensional chemotactic gradients in nerve repair scaffolds, particularly in those with multi-luminal architectures, remains extremely challenging. We developed a method that establishes(More)
— Wireless stimulation of neural tissue could enable many emerging neural prosthesis designs, and eliminate problems associated with percutaneous wires and connectors. Our laboratory has developed a 16-channel wireless floating microelectrode array (WFMA) for chronic implantation. Here, we report on its first use within in-vivo experiments, using a rat(More)
Here, we report on chronic in-vivo testing of a 16-channel wireless floating microelectrode array (WFMA) in a rat sciatic nerve model. Muscle threshold currents, charge injection levels, and charge density were monitored for electrodes of two WFMA devices implanted into animal subjects over a five month period. This type of wireless stimulation device could(More)
Loosing motor activity due to impaired or damaged nerves or muscles affects millions of people world-wide. The resulting lack of mobility and/or impaired communication bears enormous personal, economical and social costs. While several assistive technologies exist, they rely on device surrogates to compensate for the lack of movement and thus provide(More)
Intraoperative neurophysiological monitoring (IONM) is utilized to minimize neurological morbidity during spine surgery. Transcranial motor evoked potentials (TcMEPs) are principal IONM signals in which the motor cortex of the subject is stimulated with electrical pulses and the evoked potentials are recorded from the muscles of interest. Currently(More)
Anecdotal and clinical reports have suggested that radio-frequency electromagnetic fields (RF EMFs) may serve as a trigger for neuropathic pain. However, these reports have been widely disregarded, as the epidemiological effects of electromagnetic fields have not been systematically proven, and are highly controversial. Here, we demonstrate that(More)