The Human Brain–The Quaggas of Creativity 2
RT has addressed some fairly ambitious topics before, but this one may take the cake: the human brain. Fortunately, the Quaggas of Creativity are here to help; this particular quagga is taking time off from a lovely romp in the African sun to give us some insights on this demanding topic. What do we say? Baie Dankie!! (“Thank you very much” in Afrikaans).
What makes our brains special is not just their size, but also their complexity. Our brains are both the largest of any animals in ratio to our body weight and contain the largest number (88-130 billion) of neurons.
But these facts are just the tip of the iceberg.
A. Brain structure
The structure of the human brain is enormously complex (and scientists are by no means finished describing it). To begin with, the cerebral cortex, the site of abstract thought, is divided into four lobes: a) the frontal (blue area in diagram, vital to short-term memory, planning, and motivation), b) parietal (yellow area, vital to spatial sense and navigation), c) occipital (pink area, vital to processing of visual information), and d) temporal (green area, contains the hippocampus and is vital to the formation of long-term memory). But the cortex has also been divided into 52 functional areas by the anatomist Korbinian Brodman–for instance, Brodman areas 41 and 42 (in the temporal lobe) related to hearing.
Two separate areas are necessary to the processing of language: Werneicke’s area (located in the rear of the parietal lobe, it controls the deciphering of language sounds) and Broca’s area (located in the left side of the frontal lobe, it produces language sounds).
B. Brain Function
Different areas in the brain are responsible for processing information for single senses; how does the brain combine this information into consciousness?
This is the $64,000 question, and some progress has been made in answering it. For instance, in audiovisual integration, the brain can adjust audio input to match visual information, which is generally more reliable. When we listen to TV, for instance, we hear a person’s voice is coming from the screen image, when in the TV speakers produce it; our brains are set to expect a human voice from the mouth, and that is what we think we hear.
Or again, by touching objects with their hands or feet, infants build a map of what is and isn’t them. The combination of touch and sight is basic to building a “core’ feeling of self.
1) Mind. Mental processes, as RT noted in another post, are characteristic of many species. Complex language is unique to people, but many other mental phenomena (for instance, names, which bottlenose dolphins produce in the form of signature whistles) are not human monopolies.
2) Complexity. Not only are human brains enormously complex, able to handle a huge variety of information input, but brain complexity increases as we travel along the timeline from the brain’s origin (575 million years ago). RT suspects that this is so because the complexity of the environment has steadily increased over time.
3) What Works, Works. We need the brain’s complexity to achieve apparently simple tasks, such as building our understanding of what is and isn’t us. This complexity only multiplies as we deal with more and more subtle questions and issues. Everything in the physical structure has a purpose, and can serve a useful end.
You never know with a quagga; this one might be withholding information, on the theory that it’s better to learn a difficult topic bit by bit. So RT may be returning to the human brain again, if the quagga divulges more on the subject. Still, the broad day is beckoning, and RT is tempted to spend some time in the open, horsing around 😉 … RT
All images: WikiCmns, Public Domain. Top: CAT scan of the human brain; middle: diagram showing the four brain lobes; bottom: diagram showing the Broca and Werneicke areas.