@misc{cogprints1435, volume = {85}, title = {Dopamine-sensitive alternation and collateral behaviour in a Y-maze: effects of d-amphetamine and haloperidol}, author = {R.D. Oades and K. Taghzouti and H. Simon and M. Le Moal}, publisher = {Springer-Verlag}, year = {1985}, pages = {123--128}, journal = {Psychopharmacology}, keywords = {dopamine, DA, amphetamine, haloperidol, Y-maze, alternation, rearing, collateral behaviour, switching, novelty, attention, grooming, locomotion, rat, observing-response}, url = {http://cogprints.org/1435/}, abstract = {Introduction: The frequency of spontaneous alternation in a Y-maze (visiting each arm in turn at p{\ensuremath{>}}50\%) depends on the influence of the attention given to intra- and extra-maze cues. We examined the observing responses shown by rats (collateral rearing and head-turning behaviour), the habituation to the novelty and alternation responses over 15 minutes/day, four days in a row - in a Y-maze under enhanced and reduced dopamine (DA) activity (amphetamine- and haloperidol treatment). Methods: Prior to placement in a Y-maze for 15 minutes observation on 4 successive days animals were treated with either amphetamine (0.5 or 2.5 mg/kg) or pre-treated with a low dose of haloperidol (0.08 mg/kg, ip). Results: 1/ Amphetamine treated animals chose the arms at random on day 1, but after the higher dose on day 2-4 they perseverated their choice. The controls maintained their alternation over this period. 2/ The amphetamine-induced effects on alternation were prevented by prior treatment with the neuroleptic haloperidol. 3/ Amphetamine treatment increased the frequency of rearing in the middle at the choice point of the Y-maze. Haloperidol pre-treatment blocked this increase at the midpoint on day 1, and blocked the rearing behavior at the end of an arm on day 2. 4/ Amphetamine also increased the frequency of head turning and "looking", - an effect that was also prevented by haloperidol. (day 2 onwards). 5/ Haloperidol increased the duration of" looking" and of rearing at the end of an arm later in testing.. Conclusions: Two effects are postulated to have occurred. a) a conflict on day 1 between the novelty-controlled sensory or attentional effects, that leads to an alternation of arm-choice, and amphetamine-induced DA activity that facilitates an alternation of behavioural responses: -- the result was random choice and increased rearing at the choice point. b) On days 2-4 the drug-induced effects on switching motor responses came to control behaviour } }