Functional Spectroscopy Mapping of Pain Processing Cortical Areas during Non-Painful Peripheral Electrical Stimulation of the Accessory Spinal Nerve

AbstractIntraoperative speech mapping is performed to preserve language function during tumour resections that involve eloquent cortical areas. For this technique the synchronization of the picture presentation to the patient with the electrical stimulation of the cortex is of major importance. During the operative routine images are manually presented by a psychologist or neurologist to the patient and have to be coordinated with the neurosurgeon stimulating the cortex by a neurostimulator, operated by an engineer. To increase the efficiency of this procedure and to minimize the time needed to localize functional cortical areas, images should appear automatically with electrical stimulation. To achieve this synchronization, the potential combination of an existing neurostimulator with commercially available software for image display was studied. A trigger signal was created to induce the presentation of a series of line drawings showing different objects. The software to control the neurostimulator and the software for image displaying were installed on two different computers. A cable was developed to transfer the trigger signal from the neurostimulator to the computer used for picture presentation. It was shown that it is possible to induce the image display via the neurostimulator using square-wave pulses of 5 V and a width of 10 ms. Thus, we present a system that enables the automated picture presentation synchronized to the electrical stimulation of cortical regions.

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Opioid Facilitation of Rewarding Electrical Brain Stimulation Is Suppressed in Rats with Neuropathic Pain

Anesthesiology ◽

10.1097/aln.0b013e31820a4edb ◽

2011 ◽

Vol 114 (3) ◽

pp. 624-632 ◽

Cited By ~ 29

Author(s):

Eric E. Ewan ◽

Thomas J. Martin

Keyword(s):

Chronic Pain ◽

Neuropathic Pain ◽

Electrical Stimulation ◽

Ventral Tegmental Area ◽

Drugs Of Abuse ◽

Spinal Nerve ◽

Abuse Liability ◽

Prescription Opioid ◽

Ventral Tegmental ◽

Stimulation Of

Introduction Opioids are powerful analgesics, but are also common drugs of abuse. Few studies have examined how neuropathic pain alters the pharmacology of opioids in modulating limbic pathways that underlie abuse liability. Methods Rats with or without spinal nerve ligation (SNL) were implanted with electrodes into the left ventral tegmental area and trained to lever press for electrical stimulation. The effects of morphine, heroin, and cocaine on facilitating electrical stimulation of the ventral tegmental area and mechanical allodynia were assessed in SNL and control subjects. Results Responding for electrical stimulation of the ventral tegmental area was similar in control and SNL rats. The frequency at which rats emitted 50% of maximal responding was 98.2 ± 5.1 (mean ± SEM) and 93.7 ± 2.8 Hz in control and SNL rats, respectively. Morphine reduced the frequency at which rats emitted 50% of maximal responding in control (maximal shift of 14.8 ± 3.1 Hz), but not SNL (2.3 ± 2.2 Hz) rats. Heroin was less potent in SNL rats, whereas cocaine produced similar shifts in control (42.3 ± 2.0 Hz) and SNL (37.5 ± 4.2 Hz) rats. Conclusions Nerve injury suppressed potentiation of electrical stimulation of the ventral tegmental area by opioids, suggesting that the positive reinforcing effects are diminished by chronic pain. Given concerns regarding prescription opioid abuse, developing strategies that assess both analgesia and abuse liability within the context of chronic pain may aid in determining which opioids are most suitable for treating chronic pain when abuse is a concern.

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Directionally selective effects on pursuit eye movements by electrical stimulation of cortical areas MT and MST in the monkey

Neuroscience Research Supplements ◽

10.1016/0921-8696(89)90952-3 ◽

1989 ◽

Vol 9 ◽

pp. 177

Author(s):

Hidehiko Komatsu ◽

Robert H. Wurtz

Keyword(s):

Electrical Stimulation ◽

Eye Movements ◽

Pursuit Eye Movements ◽

Cortical Areas ◽

Selective Effects ◽

Stimulation Of

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Cerebral 2-deoxyglucose uptake in mice during electrical stimulation of limbic and cortical areas involved in memory processing

Behavioural Brain Research ◽

10.1016/0166-4328(87)90221-x ◽

1987 ◽

Vol 26 (2-3) ◽

pp. 236-236

Author(s):

J SIF ◽

C MOURRE ◽

C DESTRADE

Keyword(s):

Electrical Stimulation ◽

Memory Processing ◽

Cortical Areas ◽

Stimulation Of

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Role of peripheral reflexes in the initiation of the esophageal phase of swallowing

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.00411.2013 ◽

2014 ◽

Vol 306 (8) ◽

pp. G728-G737 ◽

Cited By ~ 3

Author(s):

Ivan M. Lang ◽

Bidyut K. Medda ◽

Arash Babaei ◽

Reza Shaker

Keyword(s):

Electrical Stimulation ◽

Time Delays ◽

Superior Laryngeal Nerve ◽

Sensory Innervation ◽

Cervical Esophagus ◽

Pharyngeal Phase ◽

Bolus Size ◽

Peripheral Electrical Stimulation ◽

Stimulation Of

The aim of this study was to determine the role of peripheral reflexes in initiation of the esophageal phase of swallowing. In 10 decerebrate cats, we recorded electromyographic responses from the pharynx, larynx, and esophagus and manometric data from the esophagus. Water (1–5 ml) was injected into the nasopharynx to stimulate swallowing, and the timing of the pharyngeal and esophageal phases of swallowing was quantified. The effects of transection or stimulation of nerves innervating the esophagus on swallowing and esophageal motility were tested. We found that the percent occurrence of the esophageal phase was significantly related to the bolus size. While the time delays between the pharyngeal and esophageal phases of swallowing were not related to the bolus size, they were significantly more variable than the time delays between activation of muscles within the pharyngeal phase. Transection of the sensory innervation of the proximal cervical esophagus blocked or significantly inhibited activation of the esophageal phase in the proximal cervical esophagus. Peripheral electrical stimulation of the pharyngoesophageal nerve activated the proximal cervical esophagus, peripheral electrical stimulation of the vagus nerve activated the distal cervical esophagus, and peripheral electrical stimulation the superior laryngeal nerve (SLN) had no effect on the esophagus. Centripetal electrical stimulation of the SLN activated the cervical component of the esophageal phase of swallowing before initiation of the pharyngeal phase. Therefore, we concluded that initiation of the esophageal phase of swallowing depends on feedback from peripheral reflexes acting through the SLN, rather than a central program.

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Rewarding Electrical Brain Stimulation in Rats after Peripheral Nerve Injury

Anesthesiology ◽

10.1097/aln.0b013e3182330448 ◽

2011 ◽

Vol 115 (6) ◽

pp. 1271-1280 ◽

Cited By ~ 9

Author(s):

Eric E. Ewan ◽

Thomas J. Martin

Keyword(s):

Electrical Stimulation ◽

Nerve Injury ◽

Mechanical Allodynia ◽

Intrathecal Administration ◽

Spinal Nerve ◽

Abuse Liability ◽

Prescription Opioid ◽

Maximal Response ◽

Prescription Opioids ◽

Stimulation Of

Background Prescription opioid abuse is a significant concern in treating chronic pain, yet few studies examine how neuropathic pain alters the abuse liability of commonly abused prescription opioids. Methods Normal and spinal nerve ligated (SNL) rats were implanted with electrodes into the left ventral tegmental area (VTA). Rats were trained to lever press for intracranial electrical stimulation (VTA ICSS), and the effects of methadone, fentanyl, hydromorphone, and oxycodone on facilitation of VTA ICSS were assessed. A second group of neuropathic rats were implanted with intrathecal catheters, and the effects of intrathecal clonidine, adenosine, and gabapentin on facilitation of VTA ICSS were assessed. The effects of electrical stimulation of the VTA on mechanical allodynia were assessed in SNL rats. Results Responding for VTA ICSS was similar in control and SNL rats. Methadone, fentanyl, and hydromorphone were less potent in facilitating VTA ICSS in SNL rats. Oxycodone produced a significant facilitation of VTA ICSS in control (maximum shift 24.10 ± 6.19 Hz) but not SNL rats (maximum shift 16.32 ± 7.49 Hz), but also reduced maximal response rates in SNL rats. Intrathecal administration of clonidine, adenosine, and gabapentin failed to facilitate VTA ICSS in SNL rats, and electrical stimulation of the VTA did not alter mechanical allodynia following nerve injury. Conclusions The present data suggests that the positive reinforcing effects of commonly abused prescription opioids are diminished following nerve injury. In addition, alleviation of mechanical allodynia with nonopioid analgesics does not appear to stimulate limbic dopamine pathways originating from the VTA in SNL rats.

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