Mouse and Monkey: Expression reveals cognitive states

Many years of research in human psychology have shown that certain facial expressions are Feelings It is universal across cultures. for example, Classical intercultural studies Paul Ekman and his colleagues say that certain “basic emotions” (happiness,sorrow, anger, fearsurprise, and disgust) is not only shared throughout human culture, but also known for their very similar expressions. Furthermore, facial expressions are internally cognitive states ( Note Or careless), this can be used to infer subsequent behavior.

Mouse and monkey expression

in New research Published in Natural CommunicationAlejandro Tlaie and colleagues suggest that the relationship between facial expression and internal cognitive states is extended beyond the human species. In their study, the researchers trained two monkeys (Macaa Mocadeand six mice (Homo sapiens) Navigate a naturalistic virtual foraging environment using trackballs. Animals were trained to search for a particular target while avoiding other targets and received drops of juice (monkeys) and vanilla soy milk (for mice) that were diluted when they reached their desired target. The camera tracked the animal’s facial expressions as it navigated through the virtual environment.

Use Markov switching linear Return For each (MSLR) model, the researchers inferred potential cognitive states as a function of animal facial expressions and used subsequent estimated cognitive states to predict subsequent behaviors (e.g. faster or slower reaction times, or direction of movement in a virtual environment). The model revealed the “optimal” number of hidden states in order to predict their behavior. In the case of monkeys, the data may be best predicted by four unique states. Three unique conditions were sufficient for the mouse. The researchers validated the model by successfully predicting new animal behaviors that do not contribute to model training data.

Overall facial changes rather than isolated features

Overall, this study showed that prior facial expressions can actually predict subsequent performance in foraging tasks. In mice, pupil size and whisker movement predicted reaction times during targeted trials, whereas nose movement was excellent at predicting reaction times in non-targeted trials. Similarly, monkey student size and eye movement predicted response times in non-target and targeted trials, respectively. Importantly, the information extracted from animal facial expressions could not be reduced to a single feature. Rather, behavior was best predicted by the overall combination of facial features.

The findings emphasize the importance of considering complex changes in the animal’s face rather than focusing on isolated features such as pupil size. Furthermore, although the link between facial expressions and behavior is not fixed, it depends on the internal state of the animal. Thus, just like humans, the facial expressions of mice and monkeys reflect internal factors directly related to subsequent behavior.