Effects of behaviorally rewarding hypothalamic electrical stimulation on intracellularly recorded neuronal activity in the motor cortex of awake monkeys

The study was conducted on 22 healthy men aged 18-23 years. The primary motor cortex innervating the lower limb was stimulated with transcranial magnetic stimulation. Using transcutaneous electrical stimulation of the spinal cord, evoked motor responses of the muscles of the lower extremities were initiated when electrodes were applied cutaneous between the spinous processes in the Th11-Th12 projection. Research protocol: Determination of the thresholds of BMO of the muscles of the lower extremities during TESCS; determination of the BMO threshold of the TA muscle in TMS; determination of the thresholds of the BMO of the muscles of the lower extremities during TESCS against the background of 80% and 90% TMS. It was found that magnetic stimulation of the motor cortex of the brain leads to an increase in the excitability of the neural structures of the lumbar thickening of the spinal cord and an improvement in neuromuscular interactions. Key words: transcranial magnetic stimulation, transcutaneous electrical stimulation of the spinal cord, neural networks, excitability, neuromuscular interactions.

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Values Encoded in Orbitofrontal Cortex Are Causally Related to Economic Choices

10.1101/2020.03.10.984021 ◽

2020 ◽

Cited By ~ 2

Author(s):

Sébastien Ballesta ◽

Weikang Shi ◽

Katherine E. Conen ◽

Camillo Padoa-Schioppa

Keyword(s):

Electrical Stimulation ◽

Neuronal Activity ◽

Orbitofrontal Cortex ◽

Rhesus Monkeys ◽

Fundamental Issue ◽

High Current ◽

Neural Processes ◽

Economic Choices ◽

The Brain

AbstractIt has long been hypothesized that economic choices rely on the assignment and comparison of subjective values. Indeed, when agents make decisions, neurons in orbitofrontal cortex encode the values of offered and chosen goods. Moreover, neuronal activity in this area suggests the formation of a decision. However, it is unclear whether these neural processes are causally related to choices. More generally, the evidence linking economic choices to value signals in the brain remains correlational. We address this fundamental issue using electrical stimulation in rhesus monkeys. We show that suitable currents bias choices by increasing the value of individual offers. Furthermore, high-current stimulation disrupts both the computation and the comparison of subjective values. These results demonstrate that values encoded in orbitofrontal cortex are causal to economic choices.

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Transcranial electrical stimulation through screw electrodes for intraoperative monitoring of motor evoked potentials

Journal of Neurosurgery ◽

10.3171/jns.2004.100.1.0155 ◽

2004 ◽

Vol 100 (1) ◽

pp. 155-160 ◽

Cited By ~ 24

Author(s):

Katsushige Watanabe ◽

Takashi Watanabe ◽

Akio Takahashi ◽

Nobuhito Saito ◽

Masafumi Hirato ◽

...

Keyword(s):

Electrical Stimulation ◽

Motor Cortex ◽

Evoked Potentials ◽

Intraoperative Monitoring ◽

Primary Motor Cortex ◽

Motor Evoked Potentials ◽

Transcranial Electrical Stimulation ◽

Content Type ◽

Motor Pathways ◽

Fine Print

✓ The feasibility of high-frequency transcranial electrical stimulation (TES) through screw electrodes placed in the skull was investigated for use in intraoperative monitoring of the motor pathways in patients who are in a state of general anesthesia during cerebral and spinal operations. Motor evoked potentials (MEPs) were elicited by TES with a train of five square-wave pulses (duration 400 µsec, intensity ≤ 200 mA, frequency 500 Hz) delivered through metal screw electrodes placed in the outer table of the skull over the primary motor cortex in 42 patients. Myogenic MEPs to anodal stimulation were recorded from the abductor pollicis brevis (APB) and tibialis anterior (TA) muscles. The mean threshold stimulation intensity was 48 ± 17 mA for the APB muscles, and 112 ± 35 mA for the TA muscles. The electrodes were firmly fixed at the site and were not dislodged by surgical manipulation throughout the operation. No adverse reactions attributable to the TES were observed. Passing current through the screw electrodes stimulates the motor cortex more effectively than conventional methods of TES. The method is safe and inexpensive, and it is convenient for intraoperative monitoring of motor pathways.

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