Claudio Carpio

Comportamiento inteligente y creativo : efectos de distintos tipos de instrucciones

This study assessed the effects of different types of instructions on performance in training, transfer tests and creative behavior testing, using conditional discrimination procedures. Twenty students were randomly assigned to four groups that received different types of instructions: (a) non-specific instructions; (b) instantiated instructions; (c) partial relational instructions, and (d) complete relational instructions. The results showed that non-specific instructions were correlated with ineffective performance in training, while instantiated instructions promoted greater effectiveness in training — even higher than

Different Structural Sequences: A positive Effect of Reinforcement Delay in a Conditional Discrimination Task

Nine pigeons were exposed to a matching-to-sample task in which the reinforcer delay was varied. Specific sample stimulus, comparison stimulus, and reinforcement conditional probabilities were used to establish different structural sequences. Pigeons were assigned to three different groups. Reinforcer delays for the three groups were 3 s and 1 s for group 1, 2 s for group 2, and 0 s for group 3. Pigeons in group 1 performed similarly to those in group 3, while those in group 2 performed most poorly. These data indicate that matching-to-sample performance may be enhanced by different structural sequences even when the element that makes the difference—reinforcer delay—has been previously reported as having a negative effect on matching accuracy.

Effects of variable sequences of food availability on interval time-place learning by pigeons

The effects of within session variability of the sequences of food availability in a 16 period Time Place Learning (TPL) task on the performance of pigeons were assessed. Two groups of birds were exposed to two conditions. For group 1 (N=3), the first condition consisted of a TPL task in which food could be obtained according to a Random Interval (RI) 25s schedule of reinforcement in one of four feeders, the correct feeder changed every 3min. The same sequence was repeated four times within every training session (Fixed Sequence). The second condition was exactly the same as the first one with the exception that the sequence in which the correct feeder changed was randomized, yielding a total of four randomized sequences of food availability each session (Variable Sequence). An Open Hopper Test (OHT) was conducted at the end of each condition. Birds in group 2 (N=3) experienced the same conditions but in the reverse order. Results showed high percent correct responses for both group of birds under both conditions. However, birds were able to time the availability periods duration only under the Fixed Sequence condition, as shown by anticipation, anticipation of depletion and persistence of visiting patterns on the OHT. The implications of these results to Gallistels (1990) tripartite time-place-event memory code model are discussed, pointing out that these results are in line with previous findings about the important role that spatial parameters of a TPL task can play, for accurate timing was precluded when a variable sequence was employed.

Human strategies for solving a time-place learning task: the role of counting and following verbal cues.

Two experiments were conducted to assess the emergence of time-place learning in humans. In experiment 1, a computer based software was designed in which participants had to choose to enter one of four rooms in an abandoned house search for a zombie every 3-15s. Zombies could be found in only one of these rooms every trial in 3 min periods during the 12 min sessions. After 4 training sessions, participants were exposed to a probe session in which zombies could be found in any room on every trial. Almost all participants behaved as if they were timing the availability intervals: they anticipated the changes in the location of the zombie and they persisted in their performance patterns during the probe session; however, verbal reports revealed that they were counting the number of trials in each period in order to decide when to switch between rooms. In the second experiment, the task was modified in two ways: counting was made harder by using three different intertrial ranges within each session: 2-6s, 2-11s and 2-16s. Second, labels were displaced during the final session to assess whether participants learned to click on a given place or to follow a set of verbal cues. We found that participants did not notice the label changes suggesting that they learned to click on a given place, and that a win/stay-lose/shift strategy was clearly used to decide when to switch rooms in the second experiment. The implications of verbal behavior when assessing time-place learning with humans and the possible differences in this process between humans and animals are discussed.

Presence and absence of stimulus control in temporally defined schedules

The present experiment evaluated the development of stimulus control in temporally defined schedules. Pigeons received reinforcement for the first key-peck in the presence of a nine-dot pattern in tD subcycle, whereas pecks at the same dot pattern as well as six other ones (test stimuli) were extinguished during t∆ subcycle. Across different groups test stimuli were presented at the beginning, at the middle, and at the end of t∆. Sharp and symmetrical gradients were observed with test stimuli at the beginning and at the middle of t∆, whereas higher flat or asymmetrical gradients were observed at the end of t∆. These results do not support the idea that limited-hold contingencies or correlated effects prevent stimulus control.

Effects of configurational training on simple conditional discrimination tasks

The effects of training with different stimulus configurations in a simple conditional discrimination in infants were evalatued. Two groups of six subjects were formed. One (Group E), was trained in four different stimulus configurations (one configuration for each phase) and exposed to one session of intra-dimentional, extra-dimentional and extra-configurational transfer tests after each training phase. The second group (Group SE) was only trained in one stimulus configuration but was exposed to the same tests that group E. Results show that stimulus configuration is not a relevant factor in infant performance in conditional discrimination tasks.

Probability of reinforcement and its signalizing in a temporally defined schedule

Six naive rats were used to assess the effeets of ehanging probability ofreinforeement (PRS) independently from probability ofa neutral simulus (PNS), in a temporally defined shedule. Effeets of orden of eontingent (e) and non eontingent (Ne) eonditions were also assessed; a group received the sequenee e-Ne and another the Ne-e. A positive function was observed for the first group, between rate of response and values of PRS and PNS, particulary during the non-contingent reinforcement eondition. For the seeond group only PRS effeets wwre obtained, without any systemaetic effeets over PNS. Results are examined under a parametrie perspective, pointing to the limitations of ad hoc eoneep. tions used for exptaining local effects