Biomedical subjects

Troy J Zarcone

Publications and source records attributed to Troy J Zarcone.

7 recordsLinked to original sources

PubMed2005

Use of a force-plate actometer for detecting and quantifying vertical leaping induced by amphetamine in BALB/cJ mice, but not in C57BL/6J, DBA/2J, 129X1/SvJ, C3H/HeJ, and CD-1 mice.

The force-plate actometer is a relatively new computer-based instrument with high temporal and spatial resolution that has been used to measure the behavioral effects of genetic restriction (e.g., inbred mice) and drugs (e.g., dopaminergic agonists and antagonists) on a variety of behaviors in rodents, including locomotor activity, stereotypies, tremor, and wall rearing. In the present study, the force-plate actometer was used to measure the differential effects of amphetamine-induced (10.0mg/kg) vertical leaping in five inbred mouse strains (BALB/cJ, C57BL/6J, DBA/2J, 129X1/SvJ, and C3H/HeJ) and one outbred stock (CD-1). Across a 13-day, five-injection procedure, mice of the BALB/cJ strain leaped an average of 82 times per 60-min session; the C57BL/6J, DBA/2J, 129X1/SvJ, C3H/HeJ strains and CD-1 stock always showed zero or near zero levels of vertical leaping following amphetamine treatment. The quantitative precision afforded by the force-plate actometer revealed that the mean duration of the leaps by the BALB/cJ strain was 0.18 second, and the corresponding peak force averaged 87.4 gram per leap, which was more than 400% of the average body weight of this strain. Although no evidence of behavioral sensitization was indicated for amphetamine's effects on vertical leaping, sensitization to amphetamine's effects on spatial confinement (i.e., bouts of low mobility) was observed in all mouse types. Results indicate that the force-plate actometer is an instrument well suited for detecting and quantifying both vertical leaping and collateral behaviors induced by amphetamine in mice.

Amphetamine↗

PubMed2005

Crewmember performance before, during, and after spaceflight.

The development of technologies for monitoring the welfare of crewmembers is a critical requirement for extended spaceflight. Behavior analytic methodologies provide a framework for studying the performance of individuals and groups, and brief computerized tests have been used successfully to examine the impairing effects of sleep, drug, and nutrition manipulations on human behavior. The purpose of the present study was to evaluate the feasibility and sensitivity of repeated performance testing during spaceflight. Four National Aeronautics and Space Administration crewmembers were trained to complete computerized questionnaires and performance tasks at repeated regular intervals before and after a 10-day shuttle mission and at times that interfered minimally with other mission activities during spaceflight. Two types of performance, Digit-Symbol Substitution trial completion rates and response times during the most complex Number Recognition trials, were altered slightly during spaceflight. All other dimensions of the performance tasks remained essentially unchanged over the course of the study. Verbal ratings of Fatigue increased slightly during spaceflight and decreased during the postflight test sessions. Arousal ratings increased during spaceflight and decreased postflight. No other consistent changes in rating-scale measures were observed over the course of the study. Crewmembers completed all mission requirements in an efficient manner with no indication of clinically significant behavioral impairment during the 10-day spaceflight. These results support the feasibility and utility of computerized task performances and questionnaire rating scales for repeated measurement of behavior during spaceflight.

Adult↗

PubMed2005

Differential acquisition of lever pressing in inbred and outbred mice: comparison of one-lever and two-lever procedures and correlation with differences in locomotor activity.

Recent progress in mouse genetics has led to an increased interest in developing procedures for assessing mouse behavior, but relatively few of the behavioral procedures developed involve positively reinforced operant behavior. When operant methods are used, nose poking, not lever pressing, is the target response. In the current study differential acquisition of milk-reinforced lever pressing was observed in five inbred strains (C57BL/6J, DBA/2J, 129X1/SvJ, C3H/HeJ, and BALB/cJ) and one outbred stock (CD-1) of mice. Regardless of whether one or two levers (an "operative" and "inoperative" lever) were in the operant chamber, a concomitant variable-time fixed-ratio schedule of milk reinforcement established lever pressing in the majority of mice within two 120-min sessions. Substantial differences in lever pressing were observed across mice and between procedures. Adding an inoperative lever retarded acquisition in C57BL/6J, DBA/2J, 129X1/SvJ, and C3H/HeJ mice, but not in CD-1 and BALB/cJ mice. Locomotor activity was positively correlated with number of lever presses in both procedures. Analyses of durations of the subcomponents (e.g., time to move from hopper to lever) of operant behavior revealed further differences among the six types of mice. Together, the data suggest that appetitively reinforced lever pressing can be acquired rapidly in mice and that a combination of procedural, behavioral, and genetic variables contributes to this acquisition.

Animals↗

PubMed2004

Differential acquisition of food-reinforced disk pressing by CD-1, BALB/cJ and C57BL/6J mice.

Developments in the genetic manipulation of mice have intensified interest in the relation between genes, environment and learned behavior, which in turn has led to exploration of experimental procedures for assessing genetic influences on learning using methods such as response acquisition. The requirement for multiple experimental control groups in such genetic comparisons studies amplifies the need for reliable, instrument-directed, learning assessment paradigms. The purpose of the present experiment was to implement such a procedure in several successive phases, including pre-food basal rates of interaction with sensors in a chamber, food-hopper training, and a simple disk-baiting procedure that produced differentially food-reinforced disk pressing (FR1) and provided quantitative measures of learning in outbred (CD-1) and inbred (C57BL/6J, BALB/cJ) mice. Response acquisition performances were measured in terms of the number of correct food-producing responses (disk press to hopper entry in less than 5s). The three mouse types showed differences in several performance measures prior to response acquisition training. Pre-food basal performances did not predict subsequent rate of acquisition of the target response. On average, CD-1 mice met a criterion of 50 food-producing responses slightly, but not significantly, faster than BALB/cJ mice. The C57BL/6J mice took significantly longer to meet the learning criterion and had slower response rates, due to longer after-reinforcement pausing. Procedural differences (massed versus partial/distributed training) and reinforcement parameters (duration of access) may differentially affect different mouse types independently of genetic differences in response acquisition.

Animals↗

PubMed2003

Cocaine's effects on detection, discrimination, and identification of auditory stimuli by baboons.

The perceptual effects of cocaine were examined under conditions that required baboons to detect the presence of tones as well as to identify tones of different pitches, and the results compared to the results of prior studies on cocaine's effects on the detection of tones, the discrimination of different tone pitches, and the discrimination of different human vowel sounds of similar pitch. A reaction time procedure was employed in which baboons were trained to press a lever in the presence of a visual "ready" signal, and release the lever only when one tone pitch occurred, but not release the lever when a second, different tone pitch occurred. Changes in the percentage of correct detections and median reaction times for each tone were measured following intramuscular administration of cocaine (0.01-1.0 mg/kg). Cocaine impaired tone identification and shortened reaction times to the tones in all baboons. Cocaine's effects on accuracy, however, were primarily due to elevations in false alarm rates, as opposed to detection of the stimuli themselves. The results demonstrate that cocaine impairs the discriminability of tone pitches in baboons, and that such impairments can depend upon the type of stimuli employed (tones vs. speech sounds) and the type of procedure employed (discrimination vs. identification).

Acoustic Stimulation↗

PubMed2003

Use of functional analysis methodology in the evaluation of medication effects.

The atypical antipsychotic medication risperidone was evaluated using a double-blind, placebo-controlled design in the treatment of destructive behavior in two individuals with autism. Pre-medication functional analyses indicated that destructive behavior was maintained by escape from demands, attention, or access to tangible items. For both individuals, destructive behavior during the demand condition was significantly reduced during the medication phases, whereas destructive behavior continued to occur to obtain tangible items (Reggie) and attention (Sean). In addition, there appeared to be a differential effect of the medication on self-injurious behavior (SIB) versus aggression for Sean. Results of the study demonstrate how functional analysis may provide information on those conditions and behaviors that are most likely to be affected by a specific medication.

Adult↗

PubMed2002

Cocaine's effects on the discrimination of simple and complex auditory stimuli by baboons.

The effects of cocaine on tone frequency discriminations by baboons were examined and compared with previous data for more complex acoustic stimuli (speech sounds) to see if cocaine's perceptual effects on these discriminations depends upon the type of stimulus employed (i.e., tones vs. speech sounds). Baboons pressed a lever to produce one repeating "standard" tone and released the lever only when one of four other "comparison" tones occasionally occurred in place of the standard tone. Cocaine's effects were assessed once or twice weekly by giving an intramuscular injection of cocaine hydrochloride (0.01-0.56 mg/kg) immediately prior to performing the task and by examining correct detections and reaction times for each tone following drug administration. Cocaine impaired tone discriminability, with greater impairments occurring for those tones that were more similar in frequency to the standard tone. Cocaine's perceptual effects occurred within 20-70 min following drug administration. Cocaine also impaired or facilitated the speed of responding to auditory stimuli, depending upon the drug dose and subject. The results demonstrate that cocaine can impair auditory discriminations involving simple tones, as well as speech sounds, and further supports the suggestion that cocaine's effects are focused on CNS mechanisms related to the use of pitch cues.

Acoustic Stimulation↗