Towards chronic deep brain stimulation in freely moving hemiparkinsonian rats: applicability and functionality of a fully implantable stimulation system.

This study aimed at investigating a novel fully implantable deep brain stimulation (DBS) system and its ability to modulate brain metabolism and behavior through subthalamic nucleus (STN) stimulation in a hemiparkinsonian rat model.Twelve male rats were unilaterally lesioned with 6-hydroxydopamine in the medial forebrain bundle and received a fully implantable DBS system aiming at the ipsilesional STN. Each rat underwent three cylinder tests to analyze front paw use: a PRE test before any surgical intervention, an OFF test after surgery but before stimulation onset and an ON test under DBS.

Comparison of Bladder Inhibitory Effects of Patterned Spinal Nerve Stimulation With Conventional Neuromodulation in the Rat.

Objectives: The present study compared the effectiveness of patterned frequency of spinal nerve stimulation (SNS) with continuous, fixed-frequency nerve stimulation in an animal model of the bladder reflex contraction (BRC).

Materials And Methods: In anesthetized female rats, wire electrodes were placed under each of the L6 spinal nerve to produce bilateral SNS. A cannula was placed into the bladder via the urethra, and the urethra was ligated to ensure an isovolumetric bladder.

Effects on radiation oncology treatments involving various neuromodulation devices.

Object: Where no society-based or manufacturer guidance on radiation limits to neuromodulation devices is available, this research provides the groundwork for neurosurgeons and radiation oncologists who rely on the computerized treatment plan clinically for cancer patients. The focus of the article is to characterize radiation parameters of attenuation and scatter when an incident therapeutic x-ray beam is directed upon them. At the time of this writing, manufacturers of Neuromodulation products do not recommend direct exposure of the device in the beam nor provide guidance for the maximum dose for these devices.

New approaches to eliminating common-noise artifacts in recordings from intracortical microelectrode arrays: inter-electrode correlation and virtual referencing.

Intracortical microelectrode arrays record multi-unit extracellular activity for neurophysiology studies and for brain-machine interface applications. The common first step is neural spike-detection; a process complicated by common-noise signals from motion artifacts, electromyographic activity, and electric field pickup, especially in awake/behaving subjects. Often common-noise spikes are very similar to neural spikes in their magnitude, spectral, and temporal features.

Automated reduction of non-neuronal signals from intra-cortical microwire array recordings by use of correlation technique.

Implanted intra-cortical micro-electrode arrays record multi-unit extracellular spike activity that is used in deciphering the neural basis for adaptation, learning, plasticity and as command signal for brain-machine interfaces (BMI). Detection of spike activity is the first step in successful implementation of all the aforementioned applications. However, with awake and behaving animals, micro-electrode arrays typically also record non-neuronal signals induced by the animal's movement, feeding and grooming actions.

Collagenase-aided intracortical microelectrode array insertion: effects on insertion force and recording performance.

Intracortical microelectrodes puncture the intact pia mater membrane during insertion, a process that can cause brain dimpling and trauma. To ensure that the device is able to withstand forces during implantation without buckling, the selection of acceptable implant materials and geometries is limited to rigid designs with large cross-sectional areas. Such designs likely increase insertion trauma and potentially exacerbate the chronic tissue response.

Collagenase-aided insertion of intracortical microelectrode arrays: evaluation of insertion force and chronic recording performance.

Typically intracortical electrodes are required to puncture the intact pia mater during insertion which in the process can lead to brain dimpling and trauma. Furthermore, there is interest in the development of more flexible substrates to reduce relative micromotion after implantation, but such device have difficulty penetrating the pia without buckling. In this paper a strategy for reducing the mechanical integrity of the pia's collagen network by treatment with collagenase is evaluated experimentally.