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PubMed1984

Acupuncture in the relief of respiratory arrest.

The claim the acupuncture point Jen Chung can be use to stimulate respiration was tested in live anaesthetised sheep, to determine if acupuncture was more effective than a more general nociceptive stimulus in reversing respiratory arrest. Needling this point proved significantly more effective (P<0.05) than needling the tibial nerve in stimulating breathing after respiratory arrest due to halothane. This technique may provide a useful method of reversing respiratory arrest under clinical conditions.

Journal Article↗
PubMed1980

Cognitive factors in sexual behavior.

Two major forms of cognitive behaviors are examined: perceptions and evaluations. By synthesizing the work of cognitive therapists such as Beck and Ellis, a feedback-loop model of sexual arousal is proposed. It is suggested that cognitive distortions of perception and evaluation operate in most cases of sexual dysfunction. Therefore, a more specific diagnostic schema and a more relevantly planned course of treatment may be designed by pinpointing the troublesome cognitive linkages between sexual stimuli and sexual responses.

Cognition↗
PubMed2002

Using counterconditioning to treat behavioural distress during subcutaneous injections in a paediatric rehabilitation patient.

A counterconditioning-based intervention was conducted to supplement topical anaesthesia during repeated parent-administered subcutaneous injections performed on a 7-year-old girl for anticoagulation post-stroke. Preferred activities were paired with in vivo exposure to medical stimuli, first during simulated, then actual injections. Differential positive reinforcement was provided contingent on engagement with preferred activities, button pressing in response to an auditory stimulus, and general compliance with adult instructions. Child distress was measured by direct observations and intervention effects examined using an A-B, single-subject case study design with an interrupted time-series statistical analysis for brief single-subject data. Child distress decreased significantly when behavioural intervention was provided. Parent ratings indicated that treatment effects were maintained after the intervention was turned over to the mother and continued at home. Heart rate data provided physiological evidence of counterconditioning. The results are discussed in relation to the application of conditioning and counterconditioning theory in the paediatric rehabilitation setting.

Anticoagulants↗
PubMed2003

Discrimination between outcomes in instrumental learning: effects of preexposure to the reinforcers.

In two experiments rats received instrumental training with two response levers, one response being reinforced by sucrose solution and the other by sucrose pellets. Prior to a test session, on which both levers were made available in the absence of reinforcement, the rats were given free access to one of the reinforcers, a procedure known to reduce its value. It was found that the rats responded at a lower rate on the lever that had produced the now-devalued reinforcer, but that this effect was substantial only in rats that had received preexposure to the two reinforcers before instrumental training was begun (Experiment 1). Experiment 2 demonstrated that this effect was obtained only when presentations of the two reinforcers were presented according to an inter-mixed schedule during preexposure. It is suggested that this result constitutes an instance of the perceptual learning effect in which intermixed preexposure to similar events enhances their discriminability.

Animals↗
PubMed1981

Effects of age on acquisition and maintenance of a location discrimination in rats.

Twelve-and thirty-month old Sprague Dawley rats were trained in an auditory discrimination using a discrete trial procedure with food as the reinforcer. Two thirty-month an two twelve-month animals acquired the discrimination in one trail. The asymptotic level of correct responding was lower for the old animals and this was attributed to changes in auditory threshold with age. The thirty-month animals gave more intertrial interval responses than the twelve-month animals. There was no difference in the average response latency for the two age groups.

Aging↗
PubMed2005

Feeding upon awakening in breastfeeding and bottlefeeding mothers does not affect the awakening cortisol response.

An acute breastfeeding stimulus is generally followed by a transient decrease in cortisol levels in mothers. It is currently not clear whether breastfeeding upon waking up would affect the awakening cortisol response (ACR), a significant increase in salivary cortisol levels occurring within 30-45 min after awakening. In the present study, we measured the amplitude and stability of the ACR in response to infant feeding in women who were exclusively bottle-feeding (n = 16), or breastfeeding (n = 13) or feeding their child solid food (n = 12). The results show that the type of infant feeding did not affect the amplitude and stability of the ACR. Given that the ACR has been reported to reflect physical and psychological well-being, our finding that infant feeding upon waking up might not be a confounding factor in ACR studies on the postpartum population represents valuable methodological information.

Adrenal Cortex↗
PubMed2006

Effects of preexposure on stimulus discrimination: an investigation of the mechanisms responsible for human perceptual learning.

The effect of preexposure on human perceptual learning was investigated in four experiments. In Experiments 1a and 1b, participants were preexposed to one pair of visual stimuli on an intermixed schedule (AX/BX) and one on a blocked schedule (CX_DX). The ability to discriminate between AX and BX and between CX and DX was then assessed by examining the extent to which key presses assigned to each member of a stimulus pair generalized to the other member (Experiment 1a) and by looking at the accuracy of same-different responses (Experiment 1b). Stimuli were more easily discriminated following intermixed than following blocked preexposure on both the generalization and same-different tasks. This suggests that two stimuli are more perceptually distinct after intermixed preexposure. Experiments 2a and 2b investigated the mechanisms responsible for perceptual learning using same-different tasks. The results support the suggestion that the enhanced discrimination observed after intermixed preexposure is due to increases in the salience of the unique elements.

Discrimination Learning↗
PubMed1950

An analysis of the relationship between solubility and stimulating effect in tarsal chemoreception.

The rejection thresholds of the blowfly Phormia regina Meigen for a selected series of substituted aliphatic hydrocarbons have been determined and an analysis made of the effect on stimulation of increasing the number of like substitutions from one to two, of the interaction of different types of substituent, and of the position of the substituent in the molecule. The order of stimulating efficiency (reciprocal of rejection threshold) of the functional groups which have been studied is: Br > Cl ? CH(3) ? CHO > C=O > OH. There is a consistent decrease in stimulating effect following the introduction of a second hydroxyl group. The introduction of a second C=O has little effect. Introduction of a second halogen is generally followed by a decrease in threshold. Two different species of functional group, one of which tends to increase water solubility and the other to decrease it, tend to counter-balance each other. A single oxygen-containing functional group on the end of the molecule or two of these groups which are terminal reduce the stimulating effect less than when one or more of such groups are subterminal or located elsewhere within the molecule. Branching of the carbon chain decreases effectiveness. Sulfur and oxygen linkages also decrease effectiveness. In general, the length of the free alkyl group largely determines the stimulating effectiveness. Its power is modified to varying degrees by the nature of the attached polar groups. Of all chemical properties examined, solubility alone agrees consistently with the foregoing data. Threshold varies directly with the molar solubility of the compounds in water. The fact that the threshold values for individual compounds are frequently different from those which would be expected solely on the basis of the correlation between threshold and solubility in water suggests that other factors are also concerned in stimulation. These have not yet been identified.

Generalization, Stimulus↗
PubMed2004

Disturbing visual working memory: electrophysiological evidence for a role of the prefrontal cortex in recovery from interference.

Single cell recordings in monkeys support the notion that the lateral prefrontal cortex (PFC) controls reactivation of visual working memory representations when rehearsal is disrupted. In contrast, recent fMRI findings yielded a double dissociation for PFC and the medial temporal lobe (MTL) in a letter working memory task. PFC was engaged in interference protection during reactivation while MTL was prominently involved in the retrieval of the letter representations. We present event-related potential data (ERP) that support PFC involvement in the top-down control of reactivation during a visual working memory task with endogenously triggered recovery after visual interference. A differentiating view is proposed for the role of PFC in working memory with respect to endogenous/exogenous control and to stimulus type. General implications for binding and retention mechanisms are discussed.

Adult↗
PubMed1994

Chemosensory similarities among oils: does viscosity play a role?

It is widely thought that viscosity plays an important role in the perception of fats. Rats were conditioned to avoid oil suspensions by treating them with lithium chloride after they had ingested the oil suspension. Control rats received the same lithium chloride injection after they drank vehicle. Three, chemically different, oils were examined, triglyceride oil, silicone oil and mineral oil. Rats trained to avoid a 4% aqueous suspension of one of these oils, reliably avoided suspensions containing any of the other oils, although the rats could discriminate between the oils. The viscosity of the oil suspension was slightly greater than the viscosity of the vehicle alone. However, rats trained to avoid an oil suspension, did not avoid a fluid having a viscosity similar to that of the oil suspension. In order to assess the possibility that rats could sense the viscosity of the oil separately from that of the vehicle, rats were tested for their aversion to oils having viscosities much higher and much lower than that of the oil they were trained to avoid. Rats trained to avoid triolein having a viscosity of 67 cp, reliably avoided silicone oils having viscosities of 5 and 203 cp. However, rats trained to avoid oil did not avoid an oil-free fluid having a viscosity of 22-29 cp. A final experiment examined whether the use of viscous or non-viscous vehicles influenced the conditioned aversion. No significant effect of vehicle viscosity appeared. Thus, chemically-diverse oils are perceived, by rats, to have some perceptible attribute in common. It is proposed that this common physical attribute is boundary lubrication rather than viscosity.

Animals↗
PubMed1994

Different responsiveness of the chorda tympani and glossopharyngeal nerves to L-lysine in mice.

Differential taste responsiveness and functional role of the two taste nerves, the chorda tympani (CT) and the glossopharyngeal (GL), were studied in mice by examining neural and behavioral responses to an essential amino acid, L-lysine (Lys). Relative responses to Lys were larger in the GL than in the CT nerve. The neural threshold for the Lys response was about 2.5 log units lower in the GL (about 1.0 microM) than in the CT nerve (about 300 microM). An analysis of concentration-response relationships suggests a possibility that there are two different receptors (high and low affinity types) for Lys showing different dissociation constants. The posterior tongue region possesses both types, while the anterior region possesses only the low affinity type. Behavioral aversion threshold for Lys in intact mice, measured by use of a single bottle test, was about 1.0 microM. This threshold was the same as its neural threshold in the GL nerve. Animals whose bilateral GL nerves were sectioned showed a higher aversion threshold (about 300 microM) which was the same as the neural threshold in the CT nerve. An aversion conditioned to Lys significantly generalized to L-arginine in the intact and CT-denervated mice, and L-arginine and L-histidine in the GL-denervated mice, but the generalization pattern across various taste stimuli including the four basic taste stimuli (NaCl, HCl, quinine HCl and sucrose) did not prominently differ among the intact, the GL-denervated and CT-denervated mice. These results suggest that taste sensitivity to Lys is higher in the GL than in the CT nerve, but taste quality information for Lys conveyed by two taste nerves is not largely different.

Animals↗
PubMed1980

A review of psychophysiology in early onset psychosis.

Research on psychophysiological functioning in early onset psychosis is reviewed within the context of etiological formulations stressing perceptual and selective attention abnormalities. Electroencephalographic (EEG) measures, including resting EEG level, alpha blocking, average evoked response, and contingent negative variation, have received most attention in the literature; cardiovascular and electrodermal indices have not been so extensively explored in this group of children. While the nature of differential reactivity in early onset psychosis has not been thoroughly investigated, limited evidence suggests that the central behavioral anomalies associated with the condition may result from abnormal neurophysiological reactivity to sensory stimulation. Further studies of the psychophysiological functioning of these children should yield data useful in the clarification of etiology.

Adolescent↗