Automated apparatus for the study of learning in monkey and rat

Domestic hens succeed at serial reversal learning and perceptual concept generalisation using a new automated touchscreen device

Improving the welfare of farm animals depends on our knowledge on how they perceive and interpret their environment; the latter depends on their cognitive abilities. Hence, limited knowledge of the range of cognitive abilities of farm animals is a major concern. An effective approach to explore the cognitive range of a species is to apply automated testing devices, which are still underdeveloped in farm animals. In screen-like studies, the uses of automated devices are few in domestic hens. We developed an original fully automated touchscreen device using digital computer-drawn colour pictures and independent sensible cells adapted for cognitive testing in domestic hens, enabling a wide range of test types from low to high complexity. This study aimed to test the efficiency of our device using two cognitive tests. We focused on tasks related to adaptive capacities to environmental variability, such as flexibility and generalisation capacities as this is a good start to approach more complex cognitive capacities. We implemented a serial reversal learning task, categorised as a simple cognitive test, and a delayed matching-to-sample (dMTS) task on an identity concept, followed by a generalisation test, categorised as more complex. In the serial reversal learning task, the hens performed equally for the two changing reward contingencies in only three reversal stages. In the dMTS task, the hens increased their performance rapidly throughout the training sessions. Moreover, to the best of our knowledge, we present the first positive result of identity concept generalisation in a dMTS task in domestic hens. Our results provide additional information on the behavioural flexibility and concept understanding of domestic hens. They also support the idea that fully automated devices would improve knowledge of farm animals' cognition.

An automatic experimental apparatus to study arm reaching in New World monkeys

BACKGROUND

Several species of the New World monkeys have been used as experimental models in biomedical and neurophysiological research. However, a method for controlled arm reaching tasks has not been developed for these species.

NEW METHOD

We have developed a fully automated, pneumatically driven, portable, and reconfigurable experimental apparatus for arm-reaching tasks suitable for these small primates.

RESULTS

We have utilized the apparatus to train two owl monkeys in a visually-cued arm-reaching task. Analysis of neural recordings demonstrates directional tuning of the M1 neurons.

COMPARISON WITH EXISTING METHOD(S)

Our apparatus allows automated control, freeing the experimenter from manual experiments.

CONCLUSION

The presented apparatus provides a valuable tool for conducting neurophysiological research on New World monkeys.

Brightness discrimination learning under conditions of cue enhancement by rats with lesions in the amygdala or hippocampus

Three groups of rats, one with amygdala lesions, one with hippocampal lesions and a control group were trained on a brightness discrimination task under one of three different conditions, enhancement of the negative cue, enhancement of the positive cue or a non-enhanced condition. Animals with amygdala lesions showed retarded learning compared with normal animals and those with hippocampal lesions under the positive cue enhancement condition. Under the negative cue enhancement condition animals with hipocampal lesions were significantly handicapped compared with the other two groups. Results are discussed in relation to the Douglas and Pribram concept of a reciprocal linking of the amygdala and hippocampal systems in discrimination learning with the amygdala functioning as a reinforce register system and the hippocampus as an error evaluation system.