An official website of the United States government
In this paper we present spatio-temporally controlled electrochemical stimulation of aqueous samples using an integrated CMOS microelectrode array with 131,072 pixels. We demonstrate programmable gold electrodeposition in arbitrary spatial patterns, controllable electrolysis to produce microscale hydrogen bubbles, and spatially targeted electrochemical pH modulation. Dense spatially-addressable electrochemical stimulation is important for a wide range of bioelectronics applications.
more »
« less
A Flexible and Wearable Sparse Ultrasound Array Integrated with a Functional Electrical Stimulation Array for Spatially Distributed Sequential Stimulation
- Award ID(s):
- 2500970
- PAR ID:
- 10635971
- Publisher / Repository:
- IEEE
- Date Published:
- ISBN:
- 979-8-3503-7190-1
- Page Range / eLocation ID:
- 1 to 4
- Format(s):
- Medium: X
- Location:
- Taipei, Taiwan
- Sponsoring Org:
- National Science Foundation
More Like this
-
-
We perform experiments to study the magnetic stimulus-induced changes in neural activity in dissociated cortical neurons with different stimulation parameters. The goal of performing these studies is to build on the results from our previous work that suggested magnetic stimulation may lead to improved performance of cochlear implants. A magnetic stimulator is assembled using a micro-scale coil. To detect small changes in activity, we use glass substrate MEAs to measure culture-wide synaptically-mediated response to stimulation, rather than the direct activation of individual neurons. Our initial findings show magnetic stimulation is associated with changes in network-wide firing rates, beyond those expected by spontaneous drift in activity. This suggests that the magnetic stimulation parameters we used were able to evoke neural activity. However, we observe substantial differences in the type of change induced in neural activity in different cultures and with different stimulation parameters, some showing increases in activity and others showing decreases in activity. This may be due to differences in the number and type of neurons (inhibitory or excitatory) activated by stimulation in different experiments, which in turn may be affected by differences in stimulator location and alignment, differences in stimulus pulse waveform and amplitudes, or differences in culture density or cell morphology. We also compare the power consumption and heating of this stimulation technique with that of electrical stimulation. Finally, a need to optimize the experimental setup to allow longer experiments is identified, to reach definite conclusions.more » « less
-
Abstract Studies of electrosensory systems have led to insights into a number of general issues in biology. However, investigations of these systems have been limited by the inability to precisely control spatial patterns of electrosensory input. In this paper, an electrode array and a system to selectively stimulate spatially restricted regions of an electroreceptor array are presented. The array has 96 channels consisting of chrome/gold electrodes patterned on a flexible parylene‐C substrate and encapsulated with another parylene‐C layer. The conformability of the electrode array allows for optimal current driving and surface interface conditions. Recordings of neural activity at the first central processing stage in weakly electric mormyrid fish support the potential of this system for high spatial resolution stimulation and mapping of electrosensory systems.more » « less
-
Transcranial magnetic stimulation (TMS) is one of the most widely used noninvasive brain stimulation methods. It has been utilized for both treatment and diagnosis of many neural diseases, such as neuropathic pain and loss of function caused by stroke. Existing TMS tools cannot deliver focused electric field to targeted penetration depth even though many important neurological disorders are originated from there. A breakthrough is needed to achieve noninvasive, focused brain stimulation. We demonstrated using magnetic shield to achieve magnetic focusing without sacrificing significant amount of throughput. The shield is composed of multiple layers of copper ring arrays, which utilize induced current to generate counter magnetic fields. We experimentally set up a two-pole stimulator system to verify device simulation. A transient magnetic field probe was used for field measurements. The focusing effect highly depends on the geometric design of shield. A tight focal spot with a diameter of smaller than 5 mm (plotted in MATLAB contour map) can be achieved by using copper ring arrays. With properly designed array structures and ring locations, the combined original and induced counter fields can produce a tightly focused field distribution with enhanced field strength at a depth of 7.5 mm beyond the shield plane, which is sufficient to reach many deep and critical parts of a mouse brain.more » « less
-
In this study, a thin-film, three-dimensional (3D) opto-electro array with 4 addressable microscale light-emitting diodes for surface illumination of dorsal root ganglions (DRGs) and 9 penetrating electrodes for simultaneous recordings of light-evoked DRG activities is described for Developing a tool to better understand the relationship between spindle length-sensitive afferents from hip muscles and both interlimb coordination and gait selection. Importantly, using the origami design concept, the array can be fabricated directly on a silicon wafer in a two-dimensional (2D) configuration, which can transform into a 3D structure by folding.more » « less
- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/UFFC-JS60046.2024.10793707
