In this next series of blogs I will be discussing the brain and how it learns and performs. Firstly, I will cover some basic facts (terminology) that will be helpful when we look at topics such as
• Attention • Emotion
• Memory • Context and
• Motivation
Some brain facts……
Weight: 3 pounds
Shape: Walnut
Size: Coconut
Colour: Uncooked liver
The brain is divided into two hemispheres called the cerebral cortex (commonly known as the conscious thinking centre), covered in a thin skin of deeply wrinkled grey tissue, and separated by the corpus callosum. That curved band of white tissue acts as a bridge between the two halves, shuttling information back and forth at such a rate of speed that for all practical purposes the two hemispheres act as one. With the exception of the pineal gland, every brain module is duplicated in each hemisphere- another of nature’s creative duplication systems.
The areas lying beneath the corpus callosum make up the limbic system, the area that relates to the unconscious and yet profoundly affects our experience. Its job is to feed information upward to the conscious cortex. Emotions are generated in the limbic system along with many urges that direct our behaviour and usually help in survival.
Within this limbic system, are the
Thalamus: Directs incoming information to the appropriate part of the brain for further processing.
Hypothalamus and pituitary glands: Adapt the body to environment by constantly adjusting hormones.
Hippocampus: Involved in securing long term memory
Amygdala: Registers and generates fear.
Finally, the brainstem carries information from the body into the brain and establishes general levels of alertness and such automatic tasks as breathing, blood pressure and heartbeat.
A few additional terms are needed to understand the brain’s physiology:
Neuron: The primary building block of the brain. Neurons carry electrical charges and make chemical connections to other neurons.
Axons: Long fibres (extending from the cell body) that transmit messages.
Dendrites: Short fibres (surrounding the cell body) that receive messages
Synapses: Tiny gaps between axons and dendrites( with chemical bridges) that transmit messages.
Myelin: A sheath that serves as insulation and allows electricity to flow between the axons and the dendrites.
Now we have all our terminology in place and defined , in Blog 4 we will look at how the brain organises itself to a state of ATTENTION.