Brain Unit 3 Behaviour, Populations and Environment

Learning Outcomes To learn about the structure of the brain To learn about the convoluted nature of the cerebrum To learn about the location of the discrete areas of the brain and their functions To relate the size of the discrete areas with the function they carry out

Evolution of the Brain

Brain Structure

Plasticity - Brain is flexible. If injured, the functions of the damaged part can be taken by unaffected parts. Sensory/ Motor areas - Brain receives information along sensory neurones from sensory receptors in eyes, ears, skin etc. It then sends out information along motor neurones to muscles or glands.

Cerebrum Convoluted (folded) which increases number of cell bodies 2 halves called cerebral hemispheres Controls conscientious thought, voluntary actions, determines personality etc

Areas of Cerebrum

Motor Homunculus Imaginary human whose body parts have been drawn in proportion to their mobility and fine motor control The more motor control needed, the larger the motor area required

Corpus Callosum Mass of fibres which separates cerebral hemispheres Transfers information from 1 hemisphere to the other

Cerebellum Attached to underside of brain Unconscious fine control of voluntary muscle movement and balance

Medulla Oblongata Connects brain to spinal cord Unconscious co- ordination of basic functions – breathing, heart rate, digestion, reflex actions Medulla oblongata

EEG Electroencephalogram records brain’s electrical activities

Split-brain studies when a person’s corpus callosum has been cut exchange of information between cerebral hemispheres doesn’t occur

Brain Injuries Studies for brain injuries include: Phineas Gage – frontal lobe determines personality a man with visual agnosia mistook his wife for a hat soldiers with shrapnel wounds people with brain lesions Stroke sufferers

The Facts you need to know p17 “in recent human evolutionary history ….” to “the cerebral hemispheres are ….”