Negative expectations and vulnerability to stressors in animals

Area of Science:

• Animal behavior
• Comparative psychology
• Animal welfare

Background:

• Humans exhibit stable individual differences in pessimism, influencing vulnerability to stress and mood disorders.
• Pessimism in humans is linked to negative expectations and altered responses to stressors.
• Understanding animal expectations can provide insights into their psychological well-being and stress responses.

Purpose of the Study:

• To investigate whether non-human animals display stable individual differences in expectations.
• To determine if these individual differences in expectations relate to susceptibility to stressors.
• To explore the implications for animal welfare and the use of animals as models for human mood disorders.

Main Methods:

• Utilized judgment bias tests to assess expectations in animals.
• Interpreted judgment bias as a measure of negative expectations, acknowledging potential influence of reward sensitivity.
• Reviewed existing literature on animal expectations and stressor responses.

Main Results:

• Evidence suggests that animals exhibit stable individual differences in expectations.
• Some animals consistently perceive ambiguous situations more negatively than others.
• A potential link exists between negative expectations and avoidance coping strategies, heightened responses to uncontrollable stressors, and increased risk for mood-related disorders.

Conclusions:

• Non-human animals appear to possess stable individual differences in expectations, akin to human pessimism.
• Negative expectations in animals may predispose them to negative outcomes when facing stressors.
• Further research is needed to fully elucidate the relationship between animal expectations, stress, and mood, with significant implications for captive animal welfare and translational research.