PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “SELF STIMULATION”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 775 records · Page 43Linked to original sources

Stressor-induced behavioral alterations in intracranial self-stimulation from the ventral tegmental area: evidence for regional variations.

Exposure to uncontrollable footshock reduced responding for electrical brain stimulation (ICSS) from the ventral tegmental area (VTA) of the CD-1 mouse. Such an effect, however, varied with electrode position in the tegmental field. In both a rate-dependent and a current intensity paradigm, ICSS from the dorsal VTA was reduced immediately, 24 hr and 168 hr following exposure to acute uncontrollable footshock. In contrast, ICSS from the ventral VTA was unaffected by the stressor regimen. These data are consistent with the suggestion that a stressor may reduce the rewarding value ordinarily derived from ICSS. Inasmuch as the stressor differentially affected ICSS from the dorsal and ventral tegmentum, these data provide evidence for a functional differentiation within the midbrain tegmental area.

Animals↗

Intracranial self-stimulation and wakefulness: effect of manipulating ambient brain catecholamines.

Rats were given disulfiram, an inhibitor of norepinephrine biosynthesis, to see if norepinephrine is a transmitter for motivation in electrical stimulation of the brain. Animals given the drug paused in bar pressing, appearing asleep or sedated; if replaced on the bar, they always resumed pressing at normal rates. The decrease in bar pressing may result from a direct or indirect effect of the drug on wakefulness rather than on reward.

Animals↗

The role of dopamine in intracranial self-stimulation of the ventral tegmental area.

The role of dopaminergic (DA) neurons in brain stimulation reward produced by electrical stimulation of the ventral tegmental area (VTA) was investigated in the rat. In the first experiment, extensive 6-hydroxydopamine lesions of the ascending fibers of the mesotelencephalic DA projections resulted in significant changes in intracranial self-stimulation (ICS) rate-current intensity functions when the lesion was ipsilateral to the stimulating electrode. Similar contralateral lesions had no effect on these functions, thus ruling out lesion-induced performance deficits as being responsible for the decreases in ICS rates across the wide range of current intensities that occurred after the ipsilateral lesions. In the second experiment, ICS obtained from electrodes in the VTA resulted in significant increases in the DA metabolites, 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) in the striatum, nucleus accumbens, and olfactory tubercle ipsilateral to the stimulating electrode. The ratios of DOPAC and HVA to DA, considered to be indices of DA utilization, were also increased in these brain regions ipsilateral to the electrode. No changes were observed in the contralateral striatum, nucleus accumbens, and olfactory tubercle. Similar increases were observed in stimulated "yoked" animals that received brain stimulation at identical rates and currents but did not lever-press for this stimulation. The third experiment examined the effects of lever-pressing for food on an FR8 schedule of reinforcement on DA utilization in the striatum, nucleus accumbens, and olfactory tubercle. Despite high rates of responding, no effects were observed on DOPAC:DA or HVA:DA ratios in these brain regions.(ABSTRACT TRUNCATED AT 250 WORDS)

3,4-Dihydroxyphenylacetic Acid↗

Preferential localization of self-stimulation sites in striosomes/patches in the rat striatum.

Histological sections of the mammalian striatum reveal a "matrix" that is histochemically distinguishable from patches, or "striosomes". The latter are cross sections of a compartment that consists primarily of tube-shaped structures radiating through the matrix. As a test of the hypothesis that the function of the striosome/patch compartment includes the mediation of behaviors related to reward, the present study examined electrical self-stimulation of the caudoputamen in rats with electrodes in either of the two compartments. Rats acquired and maintained bar-pressing responses that were contingent on stimulation through electrodes making contact with striosomes/patches more reliably than animals with electrodes terminating exclusively in the matrix. The results provide in vivo evidence that the striosome/patch compartment is functionally differentiated from the matrix compartment: Stimulation centered in or around the striosome/patch compartment but not in the matrix led to rapid acquisition of a new behavior.

Animals↗

Brain activation during vaginocervical self-stimulation and orgasm in women with complete spinal cord injury: fMRI evidence of mediation by the vagus nerves.

Women diagnosed with complete spinal cord injury (SCI) at T10 or above report vaginal-cervical perceptual awareness. To test whether the Vagus nerves, which bypass the spinal cord, provide the afferent pathway for this response, we hypothesized that the Nucleus Tractus Solitarii (NTS) region of the medulla oblongata, to which the Vagus nerves project, is activated by vaginal-cervical self-stimulation (CSS) in such women, as visualized by functional magnetic resonance imaging (fMRI). Regional blood oxygen level-dependent (BOLD) signal intensity was imaged during CSS and other motor and sensory procedures, using statistical parametric mapping (SPM) analysis with head motion artifact correction. Physiatric examination and MRI established the location and extent of spinal cord injury. In order to demarcate the NTS, a gustatory stimulus and hand movement were used to activate the superior region of the NTS and the Nucleus Cuneatus adjacent to the inferior region of the NTS, respectively. Each of four women with interruption, or "complete" injury, of the spinal cord (ASIA criteria), and one woman with significant, but "incomplete" SCI, all at or above T10, showed activation of the inferior region of the NTS during CSS. Each woman showed analgesia, measured at the fingers, during CSS, confirming previous findings. Three women experienced orgasm during the CSS. The brain regions that showed activation during the orgasms included hypothalamic paraventricular nucleus, medial amygdala, anterior cingulate, frontal, parietal, and insular cortices, and cerebellum. We conclude that the Vagus nerves provide a spinal cord-bypass pathway for vaginal-cervical sensibility in women with complete spinal cord injury above the level of entry into spinal cord of the known genitospinal nerves.

Adult↗

Drug addiction, psychotic illness and brain self-stimulation: effective treatment and explanatory hypothesis.

Similarities between drug addiction and psychotic illness suggested that drug addicts could be treated with intensive ECT and phenothiazine drugs, a therapeutic approach effective in more serious psychotic illnesses.The use of this intensive treatment method is described in six drug addicts. Successful results were achieved in four patients who have been followed up for two to five years. The treatment program, the preliminary investigations and the follow-up procedures are described.Particular reference is made to the brain self-stimulation studies of Olds and others in animals, and those of Heath in man. A hypothesis is advanced to explain the various aspects of the clinical picture in both psychotic illness and drug addiction.The intensive method of treatment should be considered for drug addicts whose prognosis is otherwise poor. Further investigations along the lines of the proposed hypothesis might be profitable in other types of abnormal and maladaptive behaviour.

Adult↗

Lack of depression-like effects of saccharin deprivation in rats: forced swim test, differential reinforcement of low rates and intracranial self-stimulation procedures.

In humans and laboratory animals, drug withdrawal often is associated with depression-like behaviors. In the present study, rats had unlimited free-choice access to water and a saccharin-containing solution before being subjected to repeated episodes of saccharin deprivation. Saccharin deprivation (1) reduced immobility time in the forced swim test, (2) increased reinforcement rate in rats trained to lever-press under the differential reinforcement of a low-rate (72-sec) schedule of food reinforcement, and (3) lowered intracranial self-stimulation thresholds in a discrete-trial current titration procedure. Taken together, these findings suggest that deprivation from a nondrug reinforcer, saccharin, is not associated with depression-like behaviors. In contrast, saccharin-deprived rats demonstrated improved performance in the behavioral paradigms used here.

Animals↗

Proneural gene self-stimulation in neural precursors: an essential mechanism for sense organ development that is regulated by Notch signaling.

To learn about the acquisition of neural fate by ectodermal cells, we have analyzed a very early sign of neural commitment in Drosophila, namely the specific accumulation of achaete-scute complex (AS-C) proneural proteins in the cell that becomes a sensory organ mother cell (SMC). We have characterized an AS-C enhancer that directs expression specifically in SMCs. This enhancer promotes Scute protein accumulation in these cells, an event essential for sensory organ development in the absence of other AS-C genes. Interspecific sequence comparisons and site-directed mutagenesis show the presence of several conserved motifs necessary for enhancer action, some of them binding sites for proneural proteins. These and other data indicate that the enhancer mediates scute self-stimulation, although only in the presence of additional activating factors, which most likely interact with conserved motifs reminiscent of NF-kappaB-binding sites. Cells neighboring the SMC do not acquire the neural fate because the Notch signaling pathway effectors, the Enhancer of split bHLH proteins, block this proneural gene self-stimulatory loop, possibly by antagonizing the action on the enhancer of the NF-kappaB-like factors or the proneural proteins. These data suggest a mechanism for SMC committment.

Animals↗

Effects of the dopamine D3-and autoreceptor preferring antagonist (-)-DS121 on locomotor activity, conditioned place preference and intracranial self-stimulation in the rat.

The phenylpiperidine (-)-DS121 (S-(-)-3-(-3-cyanophenyl)-N-n-propyl piperidine) represents a new class of weak stimulants acting as preferential dopamine autoreceptor antagonists. (-)-DS121 dose-dependently increases locomotor activity over a wide dose range in rats after systemic administration. (-)-DS121 also exhibits a weak preference for the D3 receptor in in vitro binding studies. The relevance of this D3 preference is not clear and it is not known whether the D3 receptor site influences reward mechanisms. The present results showed that (-)-DS121 induced place conditioning in the dose range 3.3-13.3mg/kg s.c. as did d-amphetamine (0.25-4.0mg/kg, s.c.). However, in contrast to d-amphetamine, (-)-DS121 failed to facilitate infracranial self-stimulation in the dose range that produced place conditioning. Local bilateral infusion of (-)-DS121 (0.05-53.0µg/side) into the nucleus accumbens or ventral tegmental area did not produce locomotor stimulation. A weak but significant increase in locomotor activity was detected after bilateral infusion of (-)-DS121 (66.3µg/side) into the lateral ventricles. This study suggests that the behavioural stimulant (-)-DS121 does not possess strong reward-facilitating properties and that local application in either the terminal or somatodendritic regions of the mesolimbic pathway does not produce the same degree of locomotor activity as seen after systemic administration.

Journal Article↗