麻豆传媒

In The Ravenous Brain Daniel Bor explores consciousness and suggests that its level of activity is linked to several psychiatric conditions

It is a long-standing philosophical conundrum: is consciousness somehow separate from the physical world or merely an illusion conjured up by our complex brains? It took his father鈥檚 stroke to convince Daniel Bor which side he was on.

Bor, who had previously been considering a PhD in the philosophy of mind, opted instead for one in the neuroscience of consciousness. To see his father 鈥渞obbed of his identity because a small clot on his brain had potently wounded his consciousness鈥� hammered home all too well that the mind really is the output of nothing more than a small sac of jelly.

But what an amazing sac of jelly it is. In The Ravenous Brain, Bor takes us on a tour of the fascinating world of consciousness research. He engages in 鈥渢echnological telepathy鈥�, taking part in a conversation where he communicates his thoughts using only an MRI brain scanner.

He also introduces us to conjoined twins with linked brains, an autistic synaesthete who can memorise the digits of pi up to 22,514 decimal places and chimpanzees that practise sophisticated mind games.

As well as providing a primer in the most popular current theories of consciousness, Bor introduces one of his own. This is that consciousness evolved to facilitate information processing, and thus learning and innovation.

One of Bor鈥檚 research areas is a type of information processing called chunking. We can normally hold only a few things in our working memory at one time, but if we chunk items into groups so that the group represents all the items it contains, we can manipulate more and more concepts simultaneously. MRI scans show that the prefrontal-parietal network, a broad area of the cortex that is sometimes seen as the home of consciousness, lights up particularly when we do tasks that involve such chunking.

If that seems speculative, it鈥檚 nothing compared with the final chapter, where Bor interprets several neurological and psychiatric conditions as disorders of consciousness. Autism is, for instance, a kind of supercharged consciousness, he believes, whereas his wife鈥檚 depressive episodes arising from her bipolar disorder could stem from an underactive one.

Whether or not you agree with those ideas, Bor鈥檚 engaging and knowledgeable prose, liberally sprinkled with personal vignettes and coupled with a knack for explaining complex concepts in everyday language, make this a book well worth reading.