Novelty-induced place preference behavior of rats was studied in two experiments. In the first experiment, separate groups of animals were habituated to a distinct environment 30 min daily for either zero, one,two, four or eight days. On the day following the last habituation day, animals were allowed 15 min free access to both the habituated (familiar) and a distinct novel environment. The results revealed a significant novelty preference in the two-, four- and eight-day habituation groups. In these same animals, the rate of horizontal and vertical activity was lower in the novel environment relative to the familiar environment. The influence of forebrain dopamine (DA) projections on novelty preference behavior was studied in the second experiment. Animals were given an injection of 6-hydroxydopamine (6-OHDA) into the nucleus accumbens or were given sham surgery, and then they were given four habituation days to one environment. Novelty-induced place preference was blocked in the lesioned animals, as the amount of time spent in the novel and familiar environments was not significantly different. Lesioned animals also failed to show a difference in locomotor activity between the novel and familiar environents. Subsequent assay data revealed that the 6-OHDA lesion reduce DA levels in the nucleus accumbens, anterior striatum and olfactory tubercles by over 65% as compared to sham surgery. These results suggest that novelty preference behavior may be mediated by a central DA pathway similar to that involved in other types of reinforcing stimuli, such as food, water and drugs of abuse.
|Number of pages||5|
|Journal||Pharmacology Biochemistry and Behavior|
|State||Published - Jun 1990|
Bibliographical noteFunding Information:
We would like to acknowledge the assistance of a number of students who helped in scoring the behavioral measures and in preparing surgery, including M. Castle, K. Hatrod, R. Middleton, T. Nodurft, B. Pierce, K. Placier and D. Schneider. This research was supported by United States Public Health Service grant DA05312.
- Place preference
ASJC Scopus subject areas
- Clinical Biochemistry
- Biological Psychiatry
- Behavioral Neuroscience