It turns out that rats make the same logic mistakes as humansScience and technology20:18 | March 31, 2023

Psychologists at the University of California have shown for the first time that this type of logic error is not unique to humans – mice seem to make the same mistakes.

That’s what Linda’s problem itself sounds like. Imagine that Linda is 31 years old, lonely and very intelligent, her profession is connected with philosophy. As a student, she was deeply involved in discrimination and social justice issues and also participated in anti-nuclear demonstrations. Which is more likely? 1) Linda works as a cashier in a bank; 2) Linda works as a bank teller and is actively involved in the feminist movement. While this is logically less likely than Linda, who just works as a cashier, the vast majority of people choose the latter option.

In the new study, the scientists designed two experiments in which rats had to evaluate the probability of the presence of sound alone or both light and sound to receive a food reward. Rodents were trained in two scenarios:

1. Sound + light = reward. They got candy balls if they pulled the lever when the signal was given and the steady light was on;

2. White noise = reward. In the second scenario, the rats got marbles if they pressed the lever while playing white noise and turning off the lights.

The researchers then modified the different combinations of conditions. Rats responded accordingly, avoiding lever pressing in response to a simple sound and button pressing in response to white noise. But when the scientists covered the light bulb with a piece of metal and played the sounds, the animals had to guess whether the light bulb was on or off. The rats were much more likely to believe that the light bulb behind the plate was lit.

The authors say that the tendency to exaggerate the probability of the presence of both sound and light, even if it doesn’t imply reward, suggests that rats are prone to the same logical fallacies.