Environmentally induced changes to brain morphology predict cognitive performance

Thomas W. Pike, Michael Ramsey, Anna Wilkinson
2018 Philosophical Transactions of the Royal Society of London. Biological Sciences  
The relationship between the size and structure of a species' brain and its cognitive capacity 30 has long interested scientists. Generally this work relates interspecific variation in brain 31 anatomy with performance on a variety of cognitive tasks. However, brains are known to 32 show considerable short-term plasticity in response to a range of social, ecological and 33 environmental factors. Despite this, we have a remarkably poor understanding of how this 34 impacts on an animal's
more » ... performance. Here, we non-invasively manipulated the 35 relative size of brain regions associated with processing visual and chemical information in 36 fish (the optic tectum and olfactory bulbs, respectively). We then tested performance in a 37 cognitive task in which information from the two sensory modalities was in conflict. 38 Although the fish could effectively utilise both visual and chemical information if presented 39 in isolation, when they received cues from both modalities simultaneously, those with 40 relatively better developed optic tecta showed a greater reliance on visual information, 41 while individuals with relatively better developed olfactory bulbs showed a greater reliance 42 on chemical information. These results suggest that short-term changes in brain structure, 43 possibly resulting from an attempt to minimise the costs of developing unnecessary but 44 energetically expensive brain regions, may have marked effects on cognitive performance. 45 46
doi:10.1098/rstb.2017.0287 pmid:30104432 fatcat:oymttdhcbbf4zawxhhrzjg27ie