23 documents found, page 1 of 3

Giving time a chance in the midsession reversal task

The midsession reversal task involves a simultaneous discrimination between stimuli S1 and S2. Choice of S1 but not S2 is reinforced during the first 40 trials, and choice of S2 but not S1 is reinforced during the last 40 trials. Trials are separated by a constant intertrial interval (ITI). Pigeons learn the task seemingly by timing the moment of the reversal trial. Hence, most of their errors occur around tria...

Trade-offs in stimulus control in a temporal discrimination task

To study how multiple stimuli may control discriminative behavior, we exposed fifteen pigeons to a symbolic matching-to-sample task with three samples that differed only in duration (2, 6, and 18s) and two keylight colors as comparisons. The pigeons learned to choose one comparison after the shortest sample, and the other comparison after the intermediate and longest samples. A 30-s intertrial interval (ITI), i...

Midsession reversal task with starlings: a quantitative test of the timing hypo...

In the Mid-Session Reversal task (MSR), an animal chooses between two options, S1 and S2. Rewards follow S1 but not S2 from trials 1-40, and S2 but not S1 from trials 41-80. With pigeons, the psychometric function relating S1 choice proportion to trial number starts close to 1 and ends close to 0, with indifference (PSE) close to trial 40. Surprisingly, pigeons make anticipatory errors, choosing S2 before trial...

The paradoxical effect of low reward probabilities in suboptimal choice

When offered a choice between 2 alternatives, animals sometimes prefer the option yielding less food. For instance, pigeons and starlings prefer an option that on 20% of the trials presents a stimulus always followed by food, and on the remaining 80% of the trials presents a stimulus never followed by food (the Informative Option), over an option that provides food on 50% of the trials regardless of the stimulu...

Ultimate explanations and suboptimal choice

Researchers have unraveled multiple cases in which behavior deviates from rationality principles. We propose that such deviations are valuable tools to understand the adaptive significance of the underpinning mechanisms. To illustrate, we discuss in detail an experimental protocol in which animals systematically incur substantial foraging losses by preferring a lean but informative option over a rich but non-in...

Timing in Animals: Form the Natural Environment to the Laboratory, From Data to...

O responder controlado temporalmente: desdobramentos da pesquisa com a tarefa d...

Context effects in temporal differentiation: some data and a model

We examined whether temporal context influences how animals produce a time interval. Six pigeons pecked one key to start an interval and then another key to end the interval. Reinforcement followed whenever the interval duration fell within a range of values signaled by the keylight colors. During Phase 1, keylight colors S1 and L1, intermixed across trials, signaled the ranges (0.5-1.5 s) and (1.5- 4.5 s), res...

Effects of motion on time perception

To investigate the effect of motion on time perception, participants were asked to perform either a temporal discrimination task or a temporal generalization task while running or standing still on a treadmill. In the temporal discrimination (bisection) task, 10 participants were exposed to two anchor stimuli, a 300-ms Short tone and a 700-ms Long tone, and then classified intermediate durations in terms of the...

Emergent relations in pigeons following trainingwith temporal samples