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C Bucherelli

Publications and source records attributed to C Bucherelli.

48 records · Page 3Linked to original sources
PubMed1990

The rat's right-left preference during free exploration of a multiple Y-maze.

The right-left preference of Wistar, Sprague-Dawley, and Long Evans rats of both sexes was investigated in a multiple Y-maze in which the animals had to perform three consecutive right-left choices in order to go from the common starting point to one of the eight goal arms. The rats were free to explore the maze without being subjected to punishments or rewards. Care was taken to minimize inhibitory influences on exploration (low illumination, no handling to return the rats to home cage). The statistical analysis of the total right-left choices performed by the rats showed that three groups (Wistar females, Sprague-Dawley females, and Long Evans males) exhibited a preference for the right. This preference was not related either to sex or strain, but was possibly a species characteristic.

Animals↗
PubMed1988

Aversive conditioning of homozygous and heterozygous D.I. Brattleboro rats in the light-dark box.

Active and passive avoidance, and conditioned freezing acquisition and retention were studied in HODI and HEDI Brattleboro rats. All animals were from the same source and of the same age and sex. The light-dark box test was employed. 0.6 and 2.0 mA footshocks were administered for the same number (7) of daily trials. Extinction time-course was followed for seven consecutive daily trials. Passive avoidance: the conditioned response was acquired and retained equally well by all Ss and for both shock intensities. Active avoidance: for 0.6 mA shocks HODI Ss acquired and retained the response significantly better than HEDI Ss; for 2.0 mA shocks the response was acquired equally by both groups of Ss, and retained significantly better by HODI Ss. Freezing: in general, HODI Ss exhibited less freezing then HEDI Ss. The diverse conditioned behavior of HODI and HEDI Ss in this paradigm, which allows the contemporaneous investigation of several aversive responses, does not support the hypothesis that vasopressin deficiency impairs learning and memory in the rat.

Animals↗
PubMed1987

Effects of detention and illumination on rats' exploratory behavior in a two-box apparatus.

The effects of detention and lighting intensity on the exploratory behavior of male Wistar rats have been investigated by means of several types of two-box apparatus. Experiments consisted of six consecutive daily trials. Step-through latency values were taken up to 180 sec. Even a very short detention (10 sec) within the starting box exerted a powerful inhibitory influence on the exploratory behavior of the subjects. Uniformly well-lighted surroundings (both boxes) exerted an equally powerful inhibitory influence on the same behavior. This inhibition was only slightly decreased by the availability of visual cues. Only in the apparatus in which at least one box was dark was the exploratory behavior well maintained. Both detention and bright lighting inhibited selectively the exploratory, locomotor behavior of these animals and did not inhibit other motor activities. In fact, groomings and attempts (abortive passages from one box into the other) were repeatedly performed during the increased step-through latency. These activities are discussed as indicators of a conflict between drives.

Animals↗
PubMed1987

Spontaneous and conditioned behavior of Wistar and Long Evans rats.

Spontaneous behavior (locomotion, feeding, drinking, and exploration in a two box apparatus) as well as conditioned behavior (passive and active avoidance responding, and freezing in the light-dark box apparatus) were studied in naive male Wistar and Long Evans rats. Concerning spontaneous behavior, Long Evans rats were more active during both light and dark periods, and showed better exploratory performance than Wistar rats. Concerning conditioned behavior, Long Evans rats acquired and retained better active and passive avoidance responses, and exhibited longer initial freezing than Wistar rats in the range of 0.6-1.4 mA footshocks. The results better define the important behavioral differences existing between the two strains, Long Evans rats showing consistently a higher level of alertness and a better conditioned performance.

Animals↗
PubMed1986

Some factors influencing conditioned and spontaneous behavior of rats in the light-dark box test.

Step-through and exit latencies in the light-dark box test were used to examine the effects of unconditioned exploration, the physical characteristics of the apparatus and detention on passive and active avoidance. Experiment 1, in which the subjects (Ss) received inescapable shocks in the dark chamber, shows that omission of the free exploration of the apparatus does not significantly affect acquisition and retention of either of the learned responses. Further, passive avoidance, compared with active avoidance is, by far, the better consolidated response. Experiment 2, which is the reverse of Experiment 1, (the dark chamber becomes the safe box, and the punishments are administered in the light chamber) emphasizes the role played by the physical characteristics of the two chambers of the apparatus. This role is shown by the improvement of the active avoidance response. Experiment 3 confirms the importance of detention in influencing the behavior of conditioned and control Ss. These results underscore the basic differences of active and passive avoidance responses.

Animals↗
PubMed1985

Active and passive avoidance learning in homozygous D.I. Brattleboro rats.

In homozygous D.I. rats and in Long-Evans controls the contemporaneous evolution of learning and retention of active and passive avoidance responses was studied by means of the light-dark box test. Passive avoidance performance of homozygous D.I. rats was almost equal to that of control subjects, while their active avoidance performance showed a significant deficit. Also, in homozygous D.I. rats the duration of the first freezing after being placed in the apparatus was consistently longer than in control Ss. The longer duration of this inhibitory behavior has been taken as an indication of a diminished ability of homozygous D.I. rats to respond to stress. The possible role of this diminished response to stress in determining the active avoidance deficit is discussed.

Animals↗
PubMed1984

Passive and active avoidance behavior in the light-dark box test.

The temporal evolution of passive and active avoidance behaviors has been followed in rats, using the light-dark box test, by measuring step-through and exit latencies. The employed schedule consisted of three 7 day periods (free exploration, reinforced learning, forced extinction-retention). The data show clearly that the two learned behaviors are both rapidly established and exhibit significant differences only during extinction, active avoidance apparently depending on close temporal reinforcement. The diverse role of several behavioral and neurological mechanisms is hypothesized.

Animals↗
PubMed1984

Arbitrary time unit counts as a mean to evaluate animal activities.

The quantitative assessment of the temporal distribution of animal activities (locomotion, feeding and drinking), which is of interest for behavioral studies, can be effected in several ways when observations last for long periods of time. One fairly widely used method is based on the scoring of segments of varying length of continuous ink on paper records (arbitrary activity counts), although, as far as we know, no proof has been given of the validity of this method. The relationship between the data obtained from the scoring process (arbitrary activity counts) and the absolute numerical data obtained from readings of activity counters has been tested by means of statistical analysis. The results show that there is an excellent fit between the two sets of data, thus proving the reliability of this method of assessing animal activities.

Animals↗
PubMedDate not supplied

Conditioned freezing (generalized motor inhibition) in several rat strains: its usefulness in assessing somato-vegetative responses to nociceptive stress.

Conditioned initial freezing duration was timed in the light-dark box test. Four genetically diverse groups of rats (Wistar, Long Evans, Brattleboro heterozigous for diabetes insipidus, Brattleboro homozygous for diabetes insipidus) were employed. 0.6 mA and 1.8 mA footshocks were administered as nociceptive stressors. The results showed that freezing duration easily and conveniently measures the animal's capacity of responding to stress. This finding is discussed in terms of genetically determined hormonal make-up and of CNS receptorial mechanisms. Initial freezing duration is proposed as a tool to evaluate stress responses.

Animals↗