Mind Matters Natural and Artificial Intelligence News and Analysis

TagHemispherectomy and psych test performance

brain anatomy
Real human half brain anatomy isolated on black background

A Neurosurgeon on Why Some People Function With Only Half a Brain

The study results are reassuring and they point to two larger truths

Yesterday, we ran a story about a recent study in which 40 people who had half of their brains removed (hemispherectomy) as children — due to intractable epilepsy — did unexpectedly well on psychological tests. Some say that it’s easy to explain because the brain has so many redundant elements. But is that all we need to know? We asked pediatric neurosurgeon Michael Egnor for some thoughts on that approach and he replied: The means by which people with major parts of their brains removed maintain function are not understood. It’s nonsense to say, as some do, that “The brain is massively parallel and recursive and functions under network rules and laws.” That’s typical neuroscience gibberish. The fact is that Read More ›

brain waves test
Brain model on human brain wave background

People With Half Their Brains Removed Do Well on Psych Tests

In a recent study, adults who had had hemispherectomies as children — to combat severe epilepsy — performed within 10% of other study subjects on face and word recognition

At Carnegie Mellon University’s Department of Psychology and Neuroscience Institute, researchers recently found that people who had had half their brains removed as children (due to serious epilepsy) “scored surprisingly well on face and word recognition tests”: The researchers expected that those volunteers who had only their right hemisphere would do well at face recognition but not as well at word recognition, since the right hemisphere is generally used to process images while the left hemisphere processes words; they expected the opposite results for those who still had just their left hemisphere. Instead, the researchers found that both groups performed nearly equally well and both were on average 86% accurate on the tests compared to a control group consisting of Read More ›