Transitive responding in hooded crows requires linearly ordered stimuli.

Area of Science:

• Cognitive ethology
• Animal behavior
• Comparative psychology

Background:

• Transitive responding is a key indicator of complex cognitive abilities, allowing animals to infer relationships between items not directly compared.
• Previous research has explored factors influencing transitive inference in various species, including the role of stimulus properties and reinforcement history.

Purpose of the Study:

• To investigate the role of post-choice feedback stimulus properties in facilitating transitive responding in crows.
• To determine whether crows utilize physical dimensions of feedback stimuli to make choices, or rely solely on reinforcement history.

Main Methods:

• Eight crows were trained to discriminate overlapping stimulus pairs (A+B-, B+C-, C+D-, D+E-).
• Two groups received different feedback: ordered diameter circles (ordered feedback) or constant diameter circles (constant feedback).
• A novel choice pair (BD) was presented, with reinforcement history manipulated to favor D, while ordered feedback favored B.

Main Results:

• Crows in the ordered feedback group strongly preferred stimulus B over D, indicating reliance on the physical dimension of feedback.
• Crows in the constant feedback group showed no significant preference, choosing between B and D at chance levels.
• Simulations using associative models supported the finding that orderable feedback is critical for transitive responding.

Conclusions:

• The ability to order feedback stimuli along a physical dimension significantly enhances transitive responding in crows.
• Crows appear to utilize the inherent orderability of post-choice feedback, rather than solely reinforcement history, to make inferences.
• These findings highlight the importance of stimulus properties in understanding the cognitive mechanisms underlying decision-making in corvids.