Hemispheric specialization represents a core feature of information processing in the brain of humans and other animals; however, separation of function can only be advantageous when communication systems coordinate, select and integrate information from both half brains. Scientists from the biopsychology lab have recently investigated how such systems work in pigeons and if they are influenced by envirotypic factors. Pigeons possess a lateralized visual system that is shaped by asymmetrical light stimulation during development. Comparing hemispheric-specific access to transfer information of pigeons with or without embryonic light experience demonstrates the light-modulated impact of interhemispheric communication systems. Stronger embryonic stimulation of the left hemisphere significantly enhances access to interhemispheric visual information, thereby reversing a right-hemispheric advantage that develops in the absence of embryonic light stimulation. This corroborates that environmental experiences can affect genetically determined asymmetries. This study delivers a further piece of evidence supporting the role of envirotypic factors on lateralization in the current nature vs. nurture debate.

Letzner, S., Patzke, N., Verhaal, J., Manns, M. (2014). Shaping a lateralized brain: Asymmetrical light experience modulates access to visual interhemispheric information in pigeons. Sci Rep, 4: 4253.