Diffusion Modelling Reveals the Decision Making Processes Underlying Negative Judgement Bias in Rats.

Area of Science:

• Neuroscience
• Animal Behavior
• Cognitive Science

Background:

• Emotional states significantly influence human decision-making.
• Rodents display analogous judgment biases when interpreting ambiguous stimuli, which are modifiable by affective state.
• Understanding these biases in rodents offers insights into conserved mechanisms of emotional influence on cognition.

Purpose of the Study:

• To investigate the impact of negative affective states on judgment bias in rats.
• To analyze the underlying decision-making processes affected by these emotional manipulations.

Main Methods:

• An ambiguous-cue interpretation task was employed to measure judgment bias in rats.
• Behavioral data were analyzed using diffusion model analysis.
• Independent component analysis was used to examine decision-making parameters in relation to affective state.

Main Results:

• Both acute anxiogenic drug treatment (FG7142) and chronic stress (restraint, social isolation) induced a negative judgment bias.
• Decision-making analysis revealed changes in information accumulation and decision thresholds.
• Negative affective bias resulted from a more negative interpretation of cues, reduced high-reward anticipation, and increased low-reward anticipation.

Conclusions:

• Negative affective states in rats, induced by pharmacological or chronic stress, lead to biased decision-making.
• These biases are characterized by altered cue interpretation and reward anticipation.
• The findings highlight conserved neural mechanisms underlying emotional influences on judgment and decision-making across species.