madame scientist's not-so-mad musings

The Brain on Art

◑ Art and Science combine in the incipient field of Neuroaesthetics. In 1900, Alois Riegl argued that art is completed by the perceptual and emotional involvement of the viewer. This view aligned art history with psychology. It followed that a work of art is inherently ambiguous and each person who sees it has a different interpretation. Your brain is a creativity machine that obtains incomplete information from the outside world and completes it.

◓ Some of this creative process has a structural basis, driven by the way the brain develops. Thus, the ability to be aesthetically moved is universal and common brain areas are activated across all humans. Other areas light up differently, reflecting the wide variety of emotional states associated with viewing art.

◉ Assessing Aesthetics:  In one experiment, Oxford University researchers recorded blood flow in the brain (by fMRI) of subjects who saw a series of Rembrandt paintings that were labeled authentic or copy. Actually, the paintings were mixed up so that some were labeled incorrectly. But the visual areas of the brain that lit up were the same, whether the painting was real or a good copy – not surprising, since the average person would not be expected to tell them apart. What was surprising was that the label of authenticity triggered areas associated with perceptions of reward, pleasure and monetary gain.  The paintings thought to be inauthentic generated strong spikes in working memory, as the people were actively trying to detect the flaws in the presented image. Our aesthetic judgements are subject to a variety of different influences that may be inaccessible to direct introspection but are revealed by neuroimaging. Did you know that changing the price label on wine alters our taste perception? (http://goo.gl/fJ7E1)

◕ Image Source: http://www.cell.com/cell_picture_show-weaving

◔ Story: http://www.wired.com/wiredscience/2011/12/how-does-the-brain-perceive-art/

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Toxoplasma: Cats, Rats and Mind Hacks

Bizarre and Beautiful: More than a third of the world’s population is infected with the parasite Toxoplasma gondii. We pick it up from uncooked meat or from changing a cat’s litter box. Although apparently harmless to healthy adults, “Toxo” is dangerous to the human fetus and to immuno-compromised people. This is why pregnant women and people with vulnerable immune systems are advised to avoid cats.

Mind Control: The parasite infects the limbic areas of the brain near the fear and sexual attraction regions. Because it carries a gene that codes for an enzyme crucial in dopamine production, it can alter levels of this neurotransmitter. Infected rats become oddly fearless of cats but not of anything else, making it likely that they end up in a cat’s intestine, the only place where the parasite can reproduce! They also make more testosterone and mate more, ensuring the spread of the parasite to other rats. The ability of parasites to manipulate host behavior for their own benefit is extremely rare in mammals because our blood brain barrier is so effective in keeping most pathogens out. But not this one.

Why Cats Rule the Internetz: If this parasite can profoundly affect rats, what about people? Studies have shown that infected men have altered behavior and personality including a tendency to disregard rules, higher suspiciousness and jealousy. Schizophrenics are more likely to be infected with Toxoplasma, and there are disturbing links to suicide as well. A 2006 study published in the journal Proceedings of the Royal Society B found that antipsychotic drugs, commonly used to treat schizophrenia, reverse the fearlessness effects of T. gondii in the brain. This is why the CDC classifies toxoplasmosis as a neglected parasitic disease. 

Image: A rosette of Toxoplasma gondii cells by Markus Meissner (University of Glasgow, UK) from Nature Methods http://goo.gl/E825h

Facts: http://www.cdc.gov/parasites/toxoplasmosis/

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