Social drinkers (healthy males aged 18--34) participated in three experiments that examined some of the mechanisms that may be responsible for the effects of alcohol on emotionally charged memory. In a study on incidental learning, alcohol enhanced neutral, positive and negative memory, possibly by a nonselective consolidation mechanism. Alcohol's enhancement of memory was found to not be associated (contingently related) with its incentive reward and relief effects. In another study on intentional learning, alcohol enhanced positive memory and/or inhibited negative memory, possibly reflecting a contingent relationship to its incentive effects. When the role of individual differences was examined, relatively little influence was found in mediating the effects of alcohol on incidental memory. However, alcohol's effect on intentional memory was predicted by individual differences in response to some of alcohol's acute incentive effects. The studies demonstrate that alcohol's effects on memory are independent from, and can be combined with, its incentive effects. Further, consumption of alcohol may be influenced by separate effects on memory and incentive, and by their association.

The purpose of this study was to investigate the effect of prolonged exercise on running economy. Fourteen male long distance runners performed two 90 minute runs on an outdoor 400m track at velocities equal to 65 and 80% of VO$ sb2$max. Prior to and following each 90 minute run, running economy (RE) was measured as the steady-state VO$ sb2$ during treadmill runs at speeds of 188 and 228 m/min. During the 90-min run at 65% of VO$ sb2$max, the mean weight loss was 1.3 kg. The HR was 143 bpm between minutes 5-10 and increased to 150 bpm between minutes 85-90. During the 90-min run at 80% of VO$ sb2$max, the mean weight loss was 1.4 kg. The HR was 161 bpm between minutes 5-10 and increased to 165 bpm between minutes 85-90. When the post RE test was conducted following each 90-min run, there was a significant increase in VO$ sb2$ expressed in both l/min and ml/kg$ cdot$min (a decrease in running economy). The increase in oxygen cost of running following the 90-min run at 80% of VO$ sb2$max was greater than that following the run at 65% of VO$ sb2$max.

The brain areas required for latent learning in the rat are not currently understood. Previous tasks used to assess latent learning, defined as the acquisition of neutral information that does not immediately influence behavior, have shared characteristics that prevented their use to determine the neurobiology of latent learning. This thesis describes a new task called the Latent Cue Preference (LCP) task, derived from the Conditioned Cue Preference (CCP) task that has been successfully used to determine the brain areas required for conditioning in the rat and other animals. In the LCP task, water deprived rats alternately drink a salt solution in one distinctive compartment of a CCP box apparatus and water in the other compartment over 8 days (training trials). They are then given a choice between the two compartments with no solutions present (preference test). The results of the behavioral experiments showed that this training results in two parallel forms of learning: (1) latent learning of an association between salt and salt-paired compartment cues, and (2) conditioning to water-paired compartment cues. Latent learning itself involved two components: (1) the latent association between salt and salt-paired cues, and (2) motivational information about salt deprivation used to retrieve the latent association, and used to compete with the conditioning to water-paired cues. In addition, the findings showed that latent learning and conditioning involve different neural circuits. Latent learning required an intact cortical-to-hippocampus circuit via the entorhinal cortex, while conditioning required an intact subcortical-to-hippocampus circuit via the fimbria-fornix. The acquisition and storage of the latent association depended on an intact entorhinal cortex/dorsal hippocampus circuit, while the use of motivational information to retrieve the association recruited the ventral hippocampus. Conditioning, on the other hand, required an intact fimbria-fornix, lateral amygdala, and hippocampus. These findings provide new knowledge to the field of learning and memory research, and allowed an update of the current Multiple Memory Systems model.

No description available.

The goal of the present investigation was to evaluate the role of the pulmonary diffusion capacity (as measured by DLco) in relation to exercise-induced hypoxemia in elite athletes working at near maximal exercise intensities. Twenty-four elite cyclists were submitted to a direct measurement of VO$ sb2$ max on cycle ergometer which permitted classification into one of two groups. "Desaturaters" (N = 13) if oxyhemoglobin saturation (SaO$ sb2$%), as determined by finger oxymetry, fell below 91% or "non-desaturaters" if SaO$ sb2$% remained above 91%. Subsequent determinations of the transfer capacity for CO (DLco) were made using a 3 second breath-hold technique (Gould 2400/2450), at rest as well as at 60% and 90% of previously determined VO$ sb2$ max ($>$4.0 1/min). The results show an increase in DLco from rest to the first exercise intensity (desat: 41.7 $ pm$ 5.7 to 55.1 $ pm$ 4.7; non-desat: 41.1 $ pm$ 5.8 to 57.2 $ pm$ 6.9 mlsCO/mmHg/min) without much further increase to the maximal workload (desat: 61.0 $ pm$ 6.0; non-desat: 61.4 $ pm$ 9.5 mls CO/mmHg/min). No significant differences in DLco were found between the two groups at rest or either of the two exercise intensities. Significant differences between the desat and non-desat groups were found for FVC, post-exercise FEF$ sb{25-75 %}$, and VE/VO$ sb2$. / The present results are in agreement with previous reports showing arterial desaturation in 50% of highly-trained subjects when VO$ sb2$ max $>$4.0 1/min. The present investigation cannot clearly establish the role of DLco in this response. (Abstract shortened by UMI.)

There has been a great deal of research investigating drug combinations which can increase analgesia. A number of studies have been conducted with one particular combination--opioids combined with the amphetamine drugs. Despite the existing literature, this combination is rarely used in clinical practice. One purpose of this thesis is to review the literature pertaining to the opioid-amphetamine combination. Another purpose of this thesis is to investigate whether dextroamphetamine sulfate ($ circler$Dexedrine) can potentiate morphine sulfate analgesia in rats in the formalin test (Experiment 1). To investigate whether these results can be generalized to another psychostimulant, methylphenidate hydrochloride ($ circler$Ritalin) is used in Experiment 2. Methylphenidate has been chosen instead of another amphetamine drug because it is currently being used in clinical studies without supporting evidence from animal studies. The results of the two experiments indicate that low doses of d-amphetamine and methylphenidate can potentiate the analgesic effects of morphine.

Objectives. The purpose of this study was too determine whether there were significant kinematic differences between recreational and elite hockey players and between contra-lateral lower limbs during forward hockey skating. / Methods. While skating on a hockey treadmill subjects were filmed with four synchronized digital video cameras while wearing reflective marker triads on the thighs, shanks and skates. Subjects skated within a calibrated volume at a self selected speed that they could maintain comfortably for one minute. Each subject completed three trials separated by 5 minutes of rest. Data was reduced and analyzed using programs written in MATLAB. Two-way ANOVA and Tukey Post Hoc tests were used to determine statistic significance. / Results. Elite and recreational subjects were significantly different (p≤0.05) during knee abduction and knee rotation at push off, as well as during knee abduction and knee flexion at blade contact. Contra lateral lower limbs were significantly different (p≤0.05) during ankle abduction and hip rotation at blade contact as well as during knee abduction at push off. / Conclusion. Some aspects of the skating stride are similar in elite and recreational hockey skaters but there were several kinematic differences between skill levels and contra-lateral legs. The skating kinematics of elite hockey players may serve as a model for young hockey players and recreational hockey players, helping them develop a more efficient and effective stride.

The purpose of this study was to determine the effects of an upper respiratory illness (URI) on running mechanics during a maximal VO2 exercise treadmill test. The specific measurements assessed were stride length (SL), stride frequency (SF), range of motion (ROM) of the hip, knee, and ankle, and the displacement of the center of mass (COM) during the stride cycle. Fifty-three subjects (female=25, male=28) between 18 and 30 years of age completed the study. The participants in the study were characteristically non-smokers, drank fewer than five alcoholic drinks per week, had no orthopedic problems, were not pregnant, did not suffer from hay fever or chronic colds, and were not allergic to penicillin. Rhinovirus Type 16 was used in the inoculation of the individuals. The subjects performed two maximal V02 treadmill test. The first test was before the inoculations and the second test was during the height of the illness. Stride length and SF data were derived from accelerometer data. Statistical analysis using ANOVA revealed no significant changes in SL or SF between pre- and post-inoculation treadmill tests. Based on the results of this study it was concluded that Rhinovirus Type 16 does not effect running mechanics during a maximal V02 treadmill test. / School of Physical Education

Plasma choline levels have been reported to be significantly reduced in athletes at the endof prolonged, exhaustive exercise (marathon running), and this may affect the release of acetylcholine at the neuromuscular junction (16). The purpose of the present investigation was to examine the influence of two levels of choline (from soy lecithin) ingestion on plasma choline levels and exercise performance. Ten endurance-trained male cyclists exercised on an electrically resisted ergometer for 105 minutes at a load equal to 70% V02 max, followed by an all-out, self-paced 15 minute performance ride on an isokinetic cycle. Three randomly ordered trials were performed four hours after the feedings of (A) 0.0 g, (B) 1.1 g, or (C) 1.8 g choline. Dietary intake of choline was controlled. Before and after the trials, blood samples were drawn and analyzed for serum choline (umol/liter) using an HPLC method. Feedings of 1.1 g and 1.8 g of choline significantly (p < 0.05) elevated serum choline values compared to control (A = 34.16 [± 0.63], B 38.17 [+ 0.96], and C = 42.32 [+ 0.59]).Post-exercise serum choline values, however, were not significantly different (p > 0.05) from pre-exercise levels. In addition, there were no significant differences (p > 0.05) in performance between placebo, 1.1 g, and 1.8 choline trials (2.11 x 105, 2.07 x 105, 2.07 x 105 Newton-meters, respectively). This study indicates a dose response to choline ingestion, with no effect on performance. / School of Physical Education

Oxygen consumption remains elevated above resting values for a variable period of time after exercise. Exercise intensity and duration, food intake, laboratory conditions, metabolic measurements, gender and age are all major factors affecting the duration and magnitude of excess post-exercise oxygen consumption (EPOC). In the present study, the influence of age on EPOC was studied in men of various fitness levels. Various metabolic measurements were collected for three distinct age groups, 18-25, 35-45, and 55-67 at rest and during exercise at 60% of maximal oxygen consumption until 200 ± 10 kilocalories were expended. Immediately after the exercise bout, subjects walked on the treadmill for one minute and then were seated until oxygen consumption returned to within .01 liters of the recorded resting values.Percent body fat, V02 max and exercise V02 were significantly different between age groups. The duration (23-25 minutes) and magnitude (7-11 kilocalories) of EPOC did not differ significantly between groups. However, heart rate and minute ventilation were significantly elevated above resting measurements when V02 reached resting values. In conclusion, the physiological differences associated with the aging process were not found to significantly affect the duration and magnitude of EPOC. / School of Physical Education