Testing Session (testing + session)

Distribution by Scientific Domains


Selected Abstracts


PRECLINICAL STUDY: Route of administration affects the ability of naltrexone to reduce amphetamine-potentiated brain stimulation reward in rats

ADDICTION BIOLOGY, Issue 4 2009
Mark S. Todtenkopf
ABSTRACT Opioid receptor antagonism has been shown to attenuate behavioral and neurochemical effects of amphetamine in humans and rodents. The effects of acute (oral or subcutaneous) or extended-release naltrexone (XR-NTX) were tested on the reward-enhancing effects of amphetamine using the intracranial self-stimulation (ICSS) paradigm. Acute exposure to drugs of abuse reduces the locus of rise (LOR) in the ICSS procedure, reflecting enhanced brain stimulation reward (BSR). Rats were treated once a day with naltrexone orally (PO; 5.0 mg/kg) or subcutaneously (SC; 0.5 mg/kg) for four consecutive days and tested with D-amphetamine (0.5 mg/kg, intraperitoneal) in the ICSS paradigm 30 minutes later on days 1 and 4. Separate groups of rats received XR-NTX (50 mg/kg, SC) or placebo microspheres (similar mass to XR-NTX, SC) on day 0 and tested with D-amphetamine in the ICSS paradigm on days 4, 14, 21, 28 and 41 after administration. Naltrexone plasma concentrations were determined for each amphetamine testing session using liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS). In rats pretreated with naltrexone acutely, amphetamine-potentiated BSR did not differ from vehicle-pretreated rats on either day 1 or day 4 (25,30% decrease in LOR). In XR-NTX-pretreated rats, amphetamine-potentiated BSR was reduced by 64 and 70% on days 4 and 14, respectively, compared to placebo microsphere-treated controls. This effect dissipated by day 21. Naltrexone plasma concentrations were comparable across all treatment groups (14,30 ng/ml) on days 1, 4 and 14. In summary, an extended-release formulation of naltrexone results in significant attenuation of psychostimulant-enhanced BSR that is not observed with acute naltrexone. [source]


Development of a computerized assessment for visual masking

INTERNATIONAL JOURNAL OF METHODS IN PSYCHIATRIC RESEARCH, Issue 2 2002
Michael Foster Green
Abstract Visual masking provides a highly informative means of assessing the earliest stages of visual processing. This procedure is frequently used in psychopathology research, most commonly in the study of schizophrenia. Deficits in visual masking tasks appear to reflect vulnerability factors in schizophrenia, as opposed to the symptoms of the illness. Visual masking procedures are typically conducted on a tachistoscope, which limits standardization across sites, as well as the number of variables that can be examined in a testing session. Although visual masking can be administered on a computer, most methods used so far have had poor temporal resolution and yielded a limited range of variables. We describe the development of a computerized visual masking battery. This battery includes a staircase procedure to establish an individual's threshold for target detection, and a relatively dense sampling of masking intervals. It includes both forward and backward masking trials for three different masking conditions that have been used previously in experimental psychopathology (target location, target identification with high-energy mask, and target identification with low-energy mask). Copyright © 2002 Whurr Publishers Ltd. [source]


Persistent Deficits in Heart Rate Response Habituation Following Neonatal Binge Ethanol Exposure

ALCOHOLISM, Issue 9 2009
Katherine C. Morasch
Background:, We have previously shown that the rate of habituation of the heart rate orienting response to a novel odor in rats is negatively affected by neonatal ethanol exposure. Thus far, however, only young rats (16 days of age) have been tested. Given the persistence of attention and memory problems evident in humans exposed to ethanol in utero, the purpose of this experiment was to examine the longer-term consequences of ethanol exposure on response habituation. Methods:, Ethanol (5.25 g/kg/d) was administered intragastrically to male and female Sprague-Dawley rats on postnatal days (PD) 4 to 9, and controls were given sham intubations. Animals were tested for heart rate orienting and response habituation to a novel olfactory stimulus (amyl acetate) on PD 16, 23, or 30. Results:, Animals tested on PD 16 or 23 showed normal heart rate deceleration to the novel odor, a measure of the orienting response. However, ethanol-treated subjects showed impaired response habituation compared with sham controls. While controls exhibited complete habituation within 4 to 5 trials, ethanol-treated animals continued to respond throughout the testing session, with little decrement in heart rate response magnitude across 10 stimulus presentations. A different pattern of responding was observed in animals tested during adolescence (PD 30). Control animals failed to show the typical heart rate decrease indicative of orienting, and instead showed a tendency toward tachycardia. In contrast, ethanol-treated animals tested on PD 30 showed orienting bradycardia that persisted for several trials. Conclusions:, These data suggest that there are relatively long-term consequences of neonatal ethanol exposure on nonassociative memory. This impairment in habituation may be relevant to the distractibility and poor focused attention that is pervasive among humans diagnosed with fetal alcohol spectrum disorders. [source]


Anxiolytic effects of a combination of Melissa ofcinalis and Valeriana ofcinalis during laboratory induced stress

PHYTOTHERAPY RESEARCH, Issue 2 2006
David O. Kennedy
Abstract Objective: Melissa ofcinalis (lemon balm) and Valeriana ofcinalis (valerian) have been used both traditionally and contemporaneously as mild sedatives, anxiolytics and hypnotics. Recent research has suggested that both may attenuate laboratory induced stress. As the two herbs are most often sold in combination with each other the current study assessed the anxiolytic properties of such a combination during laboratory-induced stress. Methods: In this double-blind, placebo-controlled, randomized, balanced cross-over experiment, 24 healthy volunteers received three separate single doses (600 mg, 1200 mg, 1800 mg) of a standardized product containing M. ofcinalis and V. ofcinalis extracts, plus a placebo, on separate days separated by a 7 day wash out period. Modulation of mood and anxiety were assessed during pre-dose and 1 h, 3 h and 6 h post-dose completions of a 20 min version of the Dened Intensity Stressor Simulation (DISS) battery. Cognitive performance on the four concurrent tasks of the battery was also assessed. Results: The results showed that the 600 mg dose of the combination ameliorated the negative effects of the DISS on ratings of anxiety. However, the highest dose (1800 mg) showed an increase in anxiety that was less marked but which reached signicance during one testing session. In addition, all three doses led to decrements in performance on the Stroop task module within the battery, and the two lower doses led to decrements on the overall score generated on the DISS battery. Conclusions: These results suggest that a combination of Melissa ofcinalis and Valeriana ofcinalis possesses anxiolytic properties that deserve further investigation. Copyright © 2006 John Wiley & Sons, Ltd. [source]


ORIGINAL RESEARCH,PAIN: Pain, Psychosocial, Sexual, and Psychophysical Characteristics of Women with Primary vs.

THE JOURNAL OF SEXUAL MEDICINE, Issue 1 2009
Secondary Provoked Vestibulodynia
ABSTRACT Introduction., Women with provoked vestibulodynia (PVD), a common cause of dyspareunia, are typically considered a homogeneous group. However, research suggests that differences on some factors (e.g., medical history, pain characteristics, psychological functioning, treatment response) exist based upon whether the pain was present at first intercourse (primary PVD: PVD1) or developed at some later point (secondary PVD: PVD2). Aims., The purpose of this study was to examine differences in demographic variables, pain characteristics, psychosocial and psychosexual adjustment, and pain sensitivity between women with PVD1 and PVD2. Methods., Twenty-six women suffering from PVD (13 with PVD1 and 13 with PVD2) completed a screening assessment, a standardized gynecological examination, an interview, questionnaires, and a quantitative sensory testing session. Main Outcome Measures., These included pain ratings during the gynecological examination and interview, scores on measures of psychosocial/sexual functioning (e.g., Short Form-36 [SF-36] Health Survey, Female Sexual Function Index), and thresholds and pain ratings during thermal sensory testing over the dominant forearm and vulvar vestibule. Results., The women with PVD1 were more likely to be nulliparous, but they were not significantly different from the women with PVD2 on other demographic variables or in their pain ratings during the gynecological examination. The women with PVD1 reported lower levels of social and emotional functioning and heightened anxiety surrounding body exposure during sexual activity, and they also displayed lower heat pain tolerance over the forearm and lower heat detection and pain thresholds at the vulvar vestibule than the women with PVD2. Conclusions., The findings from this study support previous research indicating that women with PVD1 and PVD2 differ in a number of domains. Further research is needed to confirm and elaborate on these findings. Sutton KS, Pukall C, and Chamberlain S. Pain, psychosocial, sexual, and psychophysical characteristics of women with primary vs. secondary provoked vestibulodynia. J Sex Med 2009;6:205,214. [source]


Cortisol Reactivity Is Positively Related to Executive Function in Preschool Children Attending Head Start

CHILD DEVELOPMENT, Issue 3 2005
Clancy Blair
This study examined relations among cortisol reactivity and measures of cognitive function and social behavior in 4- to 5-year-old children (N=169) attending Head Start. Saliva samples for the assay of cortisol were collected at the beginning, middle, and end of an approximately 45-min testing session. Moderate increase in cortisol followed by down-regulation of this increase was positively associated with measures of executive function, self-regulation, and letter knowledge but not with measures of receptive vocabulary, emotion knowledge, or false belief understanding. Regression analysis indicates that executive function accounted for the association between cortisol reactivity and self-regulation and letter knowledge. [source]


Acute cognitive effects of standardised Ginkgo biloba extract complexed with phosphatidylserine

HUMAN PSYCHOPHARMACOLOGY: CLINICAL AND EXPERIMENTAL, Issue 4 2007
D. O. Kennedy
Abstract Recent data suggest that the complexation of standardised Ginkgo biloba extract (GBE) with soy-derived phospholipids enhances the bio-availablity of GBE's active components. The current study therefore aimed to assess the comparative cognitive and mood effects of a low dose of GBE and products complexing the same extract with either phosphatidylserine or phosphatidylcholine. The study utilised a placebo-controlled, multi-dose, double-blind, balanced-crossover design. Twenty-eight healthy young participants received 120,mg GBE, 120,mg GBE complexed with phosphatidylserine (VirtivaÔ), 120,mg GBE complexed with phosphatidylcholine and a matching placebo, on separate days 7 days apart. Cognitive performance was assessed using the Cognitive Drug Research (CDR) computerised test battery and Serial Subtraction tasks immediately prior to dosing and at 1, 2.5, 4 and 6,h thereafter. The primary outcome measures were the four aspects of cognitive performance, which have previously been derived by factor analysis of CDR subtests. Levels of terpenoids (bilobalide, ginkgolide A and ginkgolide B) were concomitantly assessed in plasma samples taken pre-dose and at 3 and 6.5,h post-dose. In keeping with previous research utilising the same methodology, 120,mg of GBE was not associated with markedly improved performance on the primary outcomes. However, administration of GBE complexed with phosphatidylserine resulted both in improved secondary memory performance and significantly increased speed of memory task performance across all of the post-dose testing sessions. Enhancement following GBE complexed with phosphatidylcholine was restricted to a modest improvement in secondary memory performance which was restricted to one post-dose time point. All three treatments were associated with improved calmness. There were no significant differences in post-dose levels of terpenoids between the Ginkgo containing treatments, although this latter finding may be attributable to methodological factors. Complexation with phosphatidylserine appears to potentiate the cognitive effects associated with a low dose of GBE. Further research is required to identify whether this effect is due to the complexation of the extracts, their mere combination, or the separate psychopharmacological actions of the two extracts. Copyright © 2007 John Wiley & Sons, Ltd. [source]


Effect of scanning level and muscle condition on ultrasonographic cross-sectional measurements of the anterior masseter muscle

JOURNAL OF ORAL REHABILITATION, Issue 4 2003
S. Bertram
summary, With the disadvantage of computed tomography showing cumulative biological effects and magnetic resonance imaging posing a problem in clinical availability and cost, several authors described the technique of ultrasonography to measure non-invasively local cross-sectional dimensions (LCSDs) of masseter muscle sites. However only few studies addressed the issue of ,technique-related factors for intra- and inter-observer reliability' to gain more consistent testing and diagnosis. The purpose of the present study was to determine (1) whether the scanning level and/or the muscle condition may affect LCSD measurements and (2) whether measurements made at identical levels may be reproducible. The study included 35 subjects with signs and symtoms of temporomandibular diorders. Bilateral ultrasonographic investigation was performed with a linear (B-scan) 7,5 Mhz small-part transducer to register LCSDs of the anterior masseter muscle on three different levels. Scans were made on the relaxed and contracted muscle. Measurements were made in two sessions with a time interval of at least 5 min. Data were analysed for reproducibility by using the intra-class correlation coefficient (ICC) and the method error (ME). Scanning level and muscle condition had a significant effect on muscle measurements (P = 0,000). There was no difference in LCSD between the right and left muscle (P = 0,531). Measurements recorded at a given site were consistent across the testing sessions (P = 0,058). The scanning level with highest reproducibility was halfway between the origin and insertion (ICC = 0,92; ME = 6,2%). The data suggest that ultrasonography is a reliable method for measuring LSCDs of the anterior masseter muscle. [source]


Functional Electrical Stimulation-Supported Interval Training Following Sensorimotor-Complete Spinal Cord Injury: A Case Series

NEUROMODULATION, Issue 3 2009
Jack Crosbie PhD
ABSTRACT Objective.,To investigate the effect of interval training supported by Functional Electrical Stimulation (FES) on ambulation ability in complete spinal cord injury (SCI). Methods.,We trained four men with sensorimotor-complete (ASIA A) SCI, who achieved gait through FES of the quadriceps femoris, gluteus maximus, and common peroneal nerve on each side on a motorized treadmill. Training involved progressive interval walking exercise, consisting of periods of activity followed by equal periods of rest, repeated until muscle fatigue. We used time to muscle fatigue during continuous treadmill ambulation as the primary outcome measure. We also recorded the patterns of incremental stimulation for all training and testing sessions. Results.,All subjects increased their ambulation capacity; however, the responses varied from subject to subject. Some subjects increased the total distance walked by as much as 300% with progressive improvement over the entire training period; however, others made more modest gains and appeared to reach a performance plateau within a few training sessions. Conclusions.,FES-supported interval training offers a useful and effective strategy for strength-endurance improvement in the large muscle groups of the lower limb in motor-complete SCI. We believe that this training protocol offers a viable alternative to that of continuous walking training in people with SCI using FES to aid ambulation. [source]


Are cervical physical outcome measures influenced by the presence of symptomatology?

PHYSIOTHERAPY RESEARCH INTERNATIONAL, Issue 3 2002
Michele Sterling
Abstract Background and Purpose Outcome measures must be repeatable over time to judge changes as a result of treatment. It is unknown whether the presence of neck pain can affect measurement reliability over a time period when some change could be expected as a result of an intervention. The present study investigated the reliability of two measures, active cervical range of movement (AROM) and pressure pain thresholds (PPTs), in symptomatic and asymptomatic subjects. Method A repeated-measures study design with one week between testing sessions was used. Nineteen healthy asymptomatic subjects and 19 subjects with chronic neck pain participated in the study. The neck movements measured were: flexion, extension, right and left lateral flexion, and axial rotation. PPTs were measured over six bilateral sites, both local and remote to the cervical spine. Results The between-week intra-class correlation coefficients (ICCs2,1) for AROM ranged from 0.67 to 0.93 (asymptomatic group) and from 0.64 to 0.88 (chronic neck pain group). Standard error of measurement (SEM) was similar in both groups, from 2.66° to 5.59° (asymptomatic group) and from 2.36° to 6.72° (chronic neck pain group). ICCs2,1 for PPTs ranged from 0.70 to 0.91 (asymptomatic group) and from 0.69 to 0.92 (chronic neck pain group). SEM ranged from 11.14 to 87.71 kPa (asymptomatic group) and from 14.25 to 102.95 kPa (chronic neck pain group). Conclusions The findings of moderate to very high between-week reliability of measures of AROM and PPTs in both asymptomatic and chronic neck pain subjects suggest the presence of symptomatology does not adversely affect reliability of these measures. The results support the use of these measures for monitoring change in chronic neck pain conditions. Copyright © 2002 Whurr Publishers Ltd. [source]