Chimpanzee (Pan troglodytes) Counting in a Computerized Testing Paradigm

Using computer-mediated joystick manipulation, the ability of a common chimpanzee(Pan troglodytes) to select arrays of items equal to a given target number was examined. A random dot condition was included in which all sequence cues were eliminated as a means to reach the target numbers 1 to 4. The participant, Austin, had only the quantity of items already selected as a record of how high the count had progressed. Performance on the random dot trials was found to be significantly above chance and improvement over time was also statistically significant. Results of this experiment provide evidence that Austin behaved with a knowledge that the quantity of items selected was the objective of the task rather than adhering rigidly to any specific pattern of selection. The results indicate that Austin had the ability to discriminate the number of items needed to reach the target number and then select items individually to reach that target quantity

Uncertainty Monitoring May Promote Emergents

We suggest that the phenomenon of uncertainty monitoring in nonhuman animals contributes richly to the conception of nonhuman animals’ self-monitoring. We propose that uncertainty may play a role in the emergence of new forms of behavior that are adaptive. We recommend that Smith et al. determine the extent to which the uncertain response transfers immediately to other test paradigms

Rhesus Monkeys (Macaca mulatta) Maintain Learning Set Despite Second-order Stimulus-response Spatial Discontiguity

In many discrimination-learning tests, spatial separation between stimuli and response loci disrupts performance in rhesus macaques. However, monkeys are unaffected by such stimulusresponse spatial discontiguity when responses occur through joystick-based computerized movement of a cursor. To examine this discrepancy, five monkeys were tested on a learning-set task that required them to touch computer-graphic levers {which differed in location across experimental phases) with a cursor in order to select an associated test stimulus. The task produced both first-order (joystick and lever) and second-order (lever and stimuli) spatial discontiguity between the stimuli to be discriminated and the discriminative response. Performance was significantly better than chance for all lever locations including locations in which selection of the correct lever required moving the cursor away from the positive stimulus. Thus, rhesus macaques do not attend simply to the region around the cursor in these computerized tests, but rather they attend to relevant stimulus loci even when these are discontiguous with response and reward areas

Selection of behavioral tasks and development of software for evaluation of Rhesus Monkey behavior during spaceflight

The results of several experiments were disseminated during this semiannual period. This publication and each of these presented papers represent investigations of the continuity in psychological processes between monkeys and humans. Thus, each serves to support the animal model of behavior and performance research

Discrimination Reversal Learning in Capuchin Monkeys (Cebus apella)

Learning styles in capuchin monkeys were assessed with a computerized reversal- learning task called the mediationaJ paradigm. First, monkeys were trained to respond with 90% accuracy on a two-choice discrimination (A+B-). Then the authors examined differences in performance on three different types of reversal trials (A-B+, A-C+, B+C-), each of which offered differing predictions for performance, depending on whether the monkeys were using associative cues or rule-based strategies. Performance indicated that the monkeys mainly learned to avoid the B stimulus during training, as the A-C+ condition produced the best performance levels. Therefore, negative stimuli showed greater control over responding after reversal and reflected a more associative rather than rule-based form of learning

Chimpanzee (Pan troglodytes) counting in a computerized testing paradigm

Using computer-mediated joystick manipulation, the ability of a common chimpanzee (Pan troglodytes) to select arrays of items equal to a given target number was examined. A random dot condition was included in which all sequence cues were eliminated as a means to reach the target numbers 1 to 4. The participant, Austin, had only the quantity of items already selected as a record of how high the count had progressed. Performance on the random dot trials was found to be significantly above chance and improvement over time was also statistically significant. Results of this experiment provide evidence that Austin behaved with a knowledge that the quantity of items selected was the objective of the task rather than adhering rigidly to any specific pattern of selection. The results indicate that Austin had the ability to discriminate the number of items needed to reach the target number and then select items individually t

¿Se da lenguaje en los simios?

The authors review the evidence of symbolic representation capacity in apes and state that every language program starts from the same assumption: signs, lexigrams, and plastic tokens are indeed real vocabulary elements whenever apes are able to perform the right behaviour label in the presence of the respective fact or object. They consider as crucial the question of equivalence between labeling and symbolic representation capacity and state that no theoretical framework has been created within the animal psychology that may allow to distinguish conditioned discriminative responses from symbolic/representational ones. On the basis of their recent research work, they affirm that chimpanzees may manage to learn how to use symbols in a representative way but it is not possible to deduce from just a label/object association the existence of a symbolization or representation function. They also approach protolinguistic communication in children comparing it with that of chimpanzees and develop the true concept of symbolization. They close the article expressing that ape language studies have failed in getting true symbolization partly because they have centered themselves almost exclusively on the production aspects, neglecting the receptive competence.Los autores revisan la evidencia en favor de la capacidad de representación simbólica en simios, afirmando que todos los programas de lenguaje parten de la misma suposición: considerar signos, lexigramas y fichas de plástico como verdaderos elementos de vocabulario siempre que los simios sean capaces de ejecutar la etiqueta conductual correcta en presencia del correspondiente hecho u objeto. Consideran crucial el problema de la equivalencia entre capacidad de etiquetar y de representar simbólicamente y manifiestan que no se ha desarrollado ningún marco teórico dentro de la psicología animal que permita distinguir respuestas discriminativas condicionadas de respuestas simbólico-representacionales. Afirman que según sus investigaciones recientes la habilidad para utilizar símbolos de forma representativa puede ser alcanzada por chimpancés, pero no es posible deducir de la simple asociación entre etiqueta y objeto la existencia de esta función de representación o simbolización. También abordan la comunicación protolingüística de niños comparándola con la de chimpancés y desarrollan el concepto de verdadera simbolización, concluyendo que los estudios sobre el lenguaje de los simios han fracasado a la hora de obtener la verdadera simbolización en parte debido a que se han centrado casi exclusivamente en el aspecto de la producción, descuidando la competencia receptiva