Triiodothyronine attenuates neurocognitive dysfunction induced by sevoflurane in the developing brain of neonatal rats

Nervous systems distinguish between self- and other-generated movements by monitoring discrepancies between planned and performed actions. To do so, corollary discharges are conveyed to sensory areas and gate expected reafference. Such gating is observed in neonatal rats during wake-related movements. In contrast, twitches, which are self-generated movements produced during active (or REM) sleep, differ from wake movements in that they reliably trigger robust neural activity. Accordingly, we hypothesized that the gating actions of corollary discharge are absent during twitching. Here, we identify the external cuneate nucleus (ECN), which processes sensory input from the forelimbs, as a site of movement-dependent sensory gating during wake. Whereas pharmacological disinhibition of the ECN unmasked wake-related reafference, twitch-related reafference was unaffected. This is the first demonstration of a neural comparator that is differentially engaged depending on the kind of movement produced. This mechanism explains how twitches, although self-generated, trigger abundant reafferent activation of sensorimotor circuits in the developing brain.

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Ultrastructural Localization of Acetylcholinesterase in the Arcuate Nucleus and Median Eminence of the Rat

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100079644 ◽

1977 ◽

Vol 35 ◽

pp. 440-441

Author(s):

K.A. Carson ◽

C.B. Nemeroff ◽

M.S. Rone ◽

J.S. Kizer ◽

J.S. Hanker

Keyword(s):

Choline Acetyltransferase ◽

Median Eminence ◽

Arcuate Nucleus ◽

Cholinergic Neurons ◽

Ultrastructural Localization ◽

Male Rats ◽

Neonatal Rats ◽

Good Marker ◽

Chemical Studies ◽

High Doses

Biochemical, physiological, pharmacological, and more recently enzyme histo- chemical data have indicated that cholinergic circuits exist in the hypothalamus. Ultrastructural correlates of these pathways such as acetylcholinesterase (AchE) positive neurons in the arcuate nucleus (ARC) and stained terminals in the median eminence (ME) have yet to be described. Initial studies in our laboratories utilizing chemical lesioning and microdissection techniques coupled with microchemical and light microscopic enzyme histo- chemical studies suggested the existence of cholinergic neurons in the ARC which project to the ME (1). Furthermore, in adult male rats with Halasz deafferentations (hypothalamic islands composed primarily of the isolated ARC and the ME) choline acetyltransferase (ChAc) activity, a good marker for cholinergic neurons, was not significantly reduced in the ME and was only somewhat reduced in the ARC (2). Treatment of neonatal rats with high doses of monosodium 1-glutamate (MSG) results in a lesion largely restricted to the neurons of the ARC.

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Effects of prenatal administration of PCP on hippocampal neurogenesis in neonatal rats

Cell Biology International ◽

10.1042/cbi034s028b ◽

2010 ◽

Vol 34 (8) ◽

pp. S28-S28

Author(s):

Juan Liu ◽

Lianxiang Zhang ◽

Yujun Wen ◽

Yiwei Zhang ◽

Toshihito Suzuki

Keyword(s):

Hippocampal Neurogenesis ◽

Neonatal Rats

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Detection of Malingered Neurocognitive Dysfunction Among Patients with Acquired Brain Injuries

European Journal of Psychological Assessment ◽

10.1027/1015-5759/a000154 ◽

2013 ◽

Vol 29 (4) ◽

pp. 253-262 ◽

Cited By ~ 6

Author(s):

Omer Hegedish ◽

Dan Hoofien

Keyword(s):

Response Bias ◽

Concurrent Validity ◽

Convergent Validity ◽

Brain Injuries ◽

Neurocognitive Dysfunction ◽

Word Memory Test ◽

Malingered Neurocognitive Dysfunction ◽

Compensation Seeking ◽

Seeking Behavior ◽

Verbal Test

The Word Memory Test (WMT) is one of the most sensitive forced-choice tests available designed to evaluate negative response bias (NRB). Presently there is no valid verbal test designed to evaluate NRB for Hebrew-speaking patients. The aims of the present study were to validate the response bias measures of the WMT among Hebrew-speaking patients with acquired brain injuries and to reveal the malingering base rate among Israeli patients involved in compensation-seeking. Participants were 112 patients. The Test of Memory Malingering (TOMM) was used for convergent validity and injury related variables were used for concurrent validity. A translated version of the WMT had high split-half reliability. Regarding convergent validity, WMT effort measures had high positive correlations with the TOMM. Moreover, based on TOMM cutoff scores for classification, the WMT had reasonable classification rates. Regarding concurrent validity, multivariate logistic regression revealed that failure in the WMT was significantly predicted by normal brainscans and involvement in compensation-seeking behavior. The baserate of probable malingering was 34%. These findings emphasize the universality of the WMT in detecting NRB and establishing a malingered neurocognitive dysfunction baserate among Israeli patients involved in compensation-seeking.

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