A stimulus-location effect in contingency-governed, but not rule-based, discrimination learning.

Abstract

We tested pigeons' acquisition of a conditional discrimination task between colored grating stimuli that included choosing 1 of 2 response keys, which either appeared as white keys to the left and right of the discriminative stimulus, or were replicas of the stimulus. Pigeons failed to acquire the discrimination when the response keys were white disks but succeeded when directly responding to a replica of the stimulus. These results highlight how conditioning processes shape learning in pigeons: The results can be accounted for by supposing that, when pigeons were allowed to respond directly toward the stimulus, learning was guided by classical conditioning, but that responding to white keys demanded instrumental learning, which impaired task acquisition for pigeons. In contrast, humans completing the same paradigm showed no differential learning success depending on whether figure or position indicated the correct key. However, only participants who could state the underlying discrimination rule acquired the task, which implies that human performance in this situation relied on the deduction and application of task rules instead of associative processes.

The evolution of general intelligence

“…Such differences may be particularly pronounced between evolutionarily disparate species such as primates and birds. Pigeons consistently show purely associative solutions to problems that humans, and to some extent nonhuman primates, tend to solve by the use of rules (e.g., Lea & Wills 2008;Lea et al 2009;Maes et al 2015;Meier et al 2016;Smith et al 2011;Wills et al 2009). In humans, preferential attention to rules may expedite performances on rule-based tasks (Danforth et al 1990), but may also impair responses to experienced contingencies (Fingerman & Levine 1974;Hayes et al 1986).…”

Pigeons’ performance in a tracking change-signal procedure is consistent with the independent horse-race model.

“…Four of the pigeons (Almond, Apple, Boo and Luna) had previously served as subjects in the Stopand Change-signal experiments of Meier et al (2018), or in pilot work for those studies using similar procedures; the other four had served in unrelated experiments (Lea, Poser-Richet & Meier, 2015, and experiments using the same general design; Meier et al, 2016aMeier et al, , 2016b.…”

Behavioral Research on Captive Animals: Scientific and Ethical Concerns

“…In the 1920s, Pavlov used dogs to demonstrate the principals of classical conditioning: a dog was restrained and isolated in a room for use in a series of trials where food was presented with a neutral event (e.g., flashing of a light), so that their salivation response could be recorded (Pavlov, 1927). Still used today (e.g., Meier, Lea and McLaren, 2016), and developed in the 1920s by Skinner, the Skinner Box (sometimes referred to as an "operant chamber") confines partially food-deprived animals (often pigeons or rats) inside of a box with a device they must operate to obtain a food reward. Sometimes animals were also given amphetamines to assess the impact on their behavior under these conditions (Dews, 1955).…”

“…For example, to study concepts, such as numerosity, theory of mind, language, economic decision making, tool use, and memory Clayton and Emery, 2005;Pepperberg, 2017). In laboratory studies of this nature, an animal will typically be within a confined space and given a problem to solve, for example, using an apparatus or on a computer screen, for which they would receive food as a reward (e.g., Meier, Lea and McLaren, 2016). Some cognition research also involves invasive procedures, such as fixing recording chambers to an animal's skull (e.g., Schechtman et al, 2016); or being restrained in stereotactic frames (e.g., Neubert et al, 2015), to take brain recordings alongside behavioral measures.…”