The commissura anterior compensates asymmetries of visual representation in pigeons

ABSTRACT

This study was undertaken to understand what is transferred between hemispheres through the commissura anterior during a colour discrimination task in pigeons. We transiently blocked neuronal activity of the arcopallium of one hemisphere to interrupt interhemispheric communication. Before and during this intervention, we recorded from arcopallial neurons of the non-anaesthetized side while the animals discriminated stimuli ipsilateral to the recorded neurons. Due to the complete crossover of optic nerves in birds, we assumed that these neurons were at least in part requiring information from the other hemisphere to properly run the task. While lidocaine injections in both hemispheres caused some performance reductions, deficits of right arcopallial neurons were much larger when blocking interhemispheric transfer. Our results make it likely that visual information is exchanged through the commissura anterior in an asymmetrical manner with the left hemisphere providing the other side more information about the right visual half-field than vice versa.

KEYWORDS:

• Birds
• tectofugal system
• visual lateralization
• single unit recording

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

All data are stored in servers of both authors and available from the corresponding author on reasonable request.

Additional information

Funding

This research was supported by a grant from the Deutsche Forschungsgemeinschaft (DFG) (project number 122679504 SFB 874, project B5) and National Natural Science Foundation of China (project number 31872238).