Page - 35 - in Cyborg Mind - What Brain–Computer and Mind–Cyberspace Interfaces Mean for Cyberneuroethics

Presentation of the Brain–Mind Interface • 35 The Brainstem The brainstem consists of an extension of the spinal cord with which its organisation and functional properties share similarities. It supports an entry and exit system to the brain for a number of communication pathways that influence elements such as breathing, balance, taste, hearing, the heart and blood vessels. The Cerebellum The cerebellum holds more neurons than any other part of the brain, includ- ing the larger cerebrum (see the next section), but consists of fewer different types of neurons. The cerebellum modulates the outputs of other areas of the brain to make them more specific. It represents about 10 per cent of the brain’s total volume but contains 50 per cent of its neurons. If the cerebel- lum is removed in an animal, it can still perform most activities, but becomes much more hesitant and clumsy. The function of the cerebellum includes posture and the coordination of movements of the eyes, limbs and the head. It is also involved in motion that has been learned and perfected through practice and will adapt to new learnt movements. Moreover, it displays connections to areas of the cerebrum that are important for language as well as cognitive functions. The Cerebrum The cerebrum (Latin for brain) is the largest single part of the brain in humans and is responsible for processing information, using more than 90 per cent of the oxygen supplied to the brain. It contains the cerebral cortex, which consists of two symmetrical parts (cerebral hemispheres) in the left and right part of the skull, between which there is a clear division. The cerebral cortex is one of the most important parts of the human brain, with different specialised regions addressing motor, visual, auditory and olfactory functions, as well as those for high-level perceptual analysis of faces, places, other persons, learning, speech, cognition and emotional control.8 Cerebral cortex circuitry is extremely complex and neuroscientists are only just beginning to use new tools, such as neuroinformatics or network science together with more traditional biological examinations, to try and understand the functional connections within and between cortical regions.9 However, one important discovery in relation to the way in which human brains work is that there is no straightforward ‘one-to-one’ link between brain structures and mental processes, though particular brain areas associ- ated with particular functions do exist. Many cerebral cortex regions have numerous integrating and analytical characteristics. This means that certain This open access edition has been made available under a CC-BY-NC-ND 4.0 license thanks to the support of Knowledge Unlatched. Not for resale.