Evidence for perceptual learning in pigeons' recognition memory for pictures

In two experiments, pigeons were trained on a recognition memory task, which required them to refrain from responding to a picture seen earlier that day. They learned this discrimination without detectable reliance on cues relating to the sequence of positive and negative trials. In both experiments, performance was significantly better when the same restricted set of stimuli was used each day than when an entirely novel set of stimuli was used each day, and in the former case there was less evidence of any significant decline in performance with increases in the interval between first and second presentations of a stimulus. The results suggest a powerful perceptual learning effect.     

Transfer of serial reversal learning in the pigeon

Pigeons were trained on a series of reversals of a simultaneous visual discrimination and were then shifted to a second series of reversals with different visual discriminanda. Pigeons that were given discrimination reversals with one pair of colours (Group Colour) and then shifted to a second pair of colours made fewer errors with the second pair than the first. In contrast, pigeons that were initially given reversals with a pair of orientations (Group Orientation) and then shifted to colours made as many errors during colour reversals as Group Colour had during initial colour training. When birds in Group Colour were subsequently shifted to orientation discrimination reversals, they performed no better than Group Orientation had during initial orientation training. The present results suggest that positive transfer from one series of discrimination reversals to a second, independent series may be constrained by the nature of the stimulus shift.     

Book reviews

Commons, M. L., Herrnstein, R. J. and Rachlin, H. (Eds.). Quantitative analyses of behaviour: Matching and maximising accounts. Quantitative analyses of behuviour series, Volume 2. Cambridge, Mass.: Ballinger. 1982. Pp. 616. ISBN 0-88410-739-6

Alkon, D. L. and Farley, J. (1984). Primary neural substrates of learning and behavioural change. Cambridge: Cambridge University Press. Pp. 385. ISBN 0-521-25472-8. £35.00.

Satinoff, E. and Teitelbaum, P. (Eds.) (1983). Handbook of behavioral neurobiology, volume 6: Motivation. New York: Plenum Press. Pp. 592. ISBN 0-306-41068-0.     

Transfer of relational rules in matching and oddity learning by pigeons and corvids

Three experiments compared the performance of pigeons and corvids when they were given the opportunity to transfer the relational rule underlying matching or oddity discriminations to new sets of stimuli. In the first, pigeons and jackdaws were initially trained either on a matching or on a non-relational conditional discrimination and then transferred to a new matching discrimination. In the second, pigeons and jays were trained on a series of three matching (or oddity) discriminations with three different pairs of colours and finally tested, either with the same or the reversed rule, on matching or oddity to line orientations. In the third, pigeons and rooks were trained to perform one response when two coloured panels were the same and a different response when the two colours were different and then transferred, either with the same or the reversed rule, to a new set of colour stimuli. All three experiments produced the same result: no evidence of transfer of the relational rule by pigeons, but substantial and significant transfer by corvids.     

Matching and oddity learning in the pigeon: Transfer effects and the absence of relational learning

Three experiments examined the extent to which pigeons trained on a matching or oddity discrimination with one pair of colours showed transfer when tested on a new matching or oddity discrimination with a new pair of colours. Experiment 1 examined the effects of key spacing and a delay procedure and replicated previous reports that in the transfer stage subjects given the same kind of problem (Non-shift condition) in general learn more rapidly than those given the opposite problem (Shift condition). However, this difference appeared only when pigeons given matching in both training and transfer stages were compared to those shifted from oddity to matching; it did not appear in birds transferred to oddity. Transfer was not significantly affected by key spacing or by the delay.

Experiments 2 and 3 examined transfer from a non-relational conditional discrimination based on one set of colours to a subsequent matching or oddity task based on two new colours. Both a comparison between the results of Experiment 1 and 2 and the corresponding within-experiment comparison from Experiment 3 showed that transfer from conditional training to matching was as great as from prior training on matching, while prior training on oddity produced negative transfer on shift to matching. It was suggested that this negative transfer occurs because pigeons trained on oddity have not learned to override an initial bias towards the odd stimulus in an array. Whatever the correct explanation; the present results provide no support for the claim that pigeons solve matching or oddity discriminations relationally.     

Locus of the effect of a surprising reinforcer in the attenuation of blocking

Previous experiments on conditioned suppression in rats have shown that prior conditioning to one element of a compound conditioned stimulus paired with shock may block or prevent conditioning to the other element. Reliable conditioning may, however, occur to the added element (blocking may be attenuated), if a surprising second shock is added shortly after each compound trial. Experiment I confirmed this finding, and further showed that blocking was attenuated only when the second shock occurred 10 s after the compound trial, not when it occurred 100 s later. Experiment II showed that the surprising omission of an expected second shock 10 s after each compound trial would also attenuate blocking, thus implying that the surprising event does not itself act to reinforce conditioning to the added element, but rather permits the unconditioned stimulus (the first shock) to play its normal role as an effective reinforcer. This conclusion was confirmed by Experiment III, which showed that a surprising second shock does not produce any increase in conditioning to the added element on the trial on which it occurs; rather it serves to ensure adequate conditioning to that element on a subsequent compound trial. The implication is that the surprising event acts proactively to prevent subjects learning to ignore an otherwise redundant stimulus.     

Book reviews

Montefiore, A. & Noble, D. (Eds.). (1989). Goals, no-goals and own goals: A debate on goal-directed and intentional behaviour. London: Unwin Hyman. Pp. ix + 304. ISBN 0-04-445341-8. £30.00 (hardback).

McNaughton, N. (1989). Biology and emotion. Cambridge: Cambridge University Press. Pp. 228. ISBN 0-521-26527-4. £27.50 (hardback); ISBN 0-521-31938-2. £9.95 (paperback).

Amsel, A. (1989). Behaviorism, neobehaviorism, and cognitivism in learning theory: Historical and contemporary perspectives. Hillsdale, NJ: Lawrence Erlbaum Associates, Inc. Pp. 105. ISBN 0-8058-0332-7. £15.00 (hardback).

Bolles, R. C. & Beecher, M. D. (1988). Evolution and learning. Hillsdale, NJ: Lawrence Erlbaum Associates, Inc. Pp. 263 + xi. ISBN 89589-542-8. £23.95 (hardback).

Davey, Graham (1989). Ecological learning theory. London: Toutledge. Pp. 392 + xv. ISBN 0-415-01190-6. £14.95 (paperback).

Davison, M. & McCarthy, D. (1988). The matching law: A research review. Hillsdale, NJ: Lawrence Erlbaum Associates, Inc. Pp. 285. ISBN 0-90959-923-7. £29.95 (hardback).     

Effects of pre-exposure to the same or different pattern of extra-maze cues on subsequent extra-maze discrimination

In two experiments, rats learned a spatial discrimination between maze arms defined by their relationship to a variety of extra-maze cues. Prior exposure to the actual arms between which animals were required to discriminate tended to retard subsequent learning (by comparison with a control group either given no pre-exposure to the extra-maze cues or exposed only to arms pointing in the opposite direction), whereas prior exposure to arms intermediate between those used in discrimination training tended to facilitate subsequent learning. These results are consistent with the suggestion that pre-exposure will facilitate discrimination learning when it reduces the associability of features or elements common to the stimuli between which animals are required to discriminate, more than it reduces the associability of the features or elements unique to each.     

Development and Validation of a Quantitative Measure of Intensive Parenting Attitudes

Intensive mothering (IM) attitudes have been considered the dominant discourse of motherhood, but have only been assessed qualitatively The goal of this study was to develop a quantitative scale to assess these ideologies, their construct validity, and their relationship to relevant constructs (i.e., work status and division of household labor). An on-line questionnaire was given to 595 mothers asking 56 questions assessing different aspects of IM attitudes as well as several validation measures. An Exploratory Factor Analysis on 315 randomly selected mothers yielded a 5 factor solution. A Confirmatory Factor Analysis on the remaining 280 mothers demonstrated good fit. The five factors expressed the ideas that (1) women are inherently better at parenting than men (Essentialism), (2) parenting should be fulfilling (Fulfillment), (3) children should be cognitively stimulated by parents (Stimulation), (4) mothering is difficult (Challenging), and (5) parents should prioritize the needs of the child (Child-Centered). Scales had adequate reliability and construct validity compared to the Parental Investment in the Child questionnaire, the Parenting Sense of Competence Scale, and Beliefs about Maternal Employment. The Essentialism, Fulfillment, and Challenging scales were positively related to having more responsibility for child care and household chores. Stay-at-home mothers had higher scores on Essentialism and lower scores on Stimulation than both part-time and full-time working mothers supporting the notion that both working and non-working mothers have intensive parenting ideologies that are manifested in different ways.