http://snipurl.com/g1o9j <http://snipurl.com/g1o9j> [www_economist_com]
excerpt: The question of how the autistic brain differs physically from that of neurotypicals was addressed by Manuel Casanova of the University of Louisville, in Kentucky. Dr Casanova has spent many years dissecting both. His conclusion is that the main difference is in the structure of the small columns of nerve cells that are packed together to form the cerebral cortex. The cortical columns of those on the autistic spectrum are narrower than those of neurotypicals, and their cells are organised differently. The upshot of these differences is that the columns in an autistic brain seem to be more connected than normal with their close neighbours, and less connected with their distant ones. Though it is an interpretative stretch, that pattern of connection might reduce a person's ability to generalise (since disparate data are less easily integrated) and increase his ability to concentrate (by drawing together similar inputs). Rain and sunshine Given such anatomical differences, then, what hope is there for the neurotypical who would like to be a savant? Some, possibly. There are examples of people suddenly developing extraordinary skills in painting and music in adult life as a result of brain damage caused by accidents or strokes. That, perhaps, is too high a price to pay. But Allan Snyder of the University of Sydney has been able to induce what looks like a temporary version of this phenomenon using magnetism. Dr Snyder argues that savant skills are latent in everyone, but that access to them is inhibited in non-savants by other neurological processes. He is able to remove this inhibition using a technique called repetitive transcranial magnetic stimulation. Applying a magnetic field to part of the brain disrupts the electrical activity of the nerve cells for a few seconds. Applying such a field repeatedly can have effects that last for an hour or so. The technique has been approved for the treatment of depression, and is being tested against several other conditions, including Parkinson's disease and migraines. Dr Snyder, however, has found that stimulating an area called the left anterior temporal lobe improves people's ability to draw things like animals and faces from memory. It helps them, too, with other tasks savants do famously well—proofreading, for example, and estimating the number of objects in a large group, such as a pile of match sticks. It also reduces "false" memories (savants tend to remember things literally, rather than constructing a mnemonic narrative and remembering that).
