Intro to Psychology I Textbook Notes
Chapter 4 Biology of Behaviour
The Brain and its Components (Part 1 – page 89)
- There are different types of nerve cells, in terms of shape, size, and the kinds of chemicals they
- Different parts of the nervous system are responsible for different functions.
- Donald Hebb considered how individual nerve cells are organized into larger units, and they units
can generate the higher processes of the brain (i.e. memory, thought, and decision making).
- Nerve cells of the brain are organized in modules – clusters of nerve cells that communicate with
- Individual modules do not stand alone, they are connected to other neural circuits, receiving
information from some of them, processing this information, and sending the results to other
modules. Specific modules have specific functions.
Structure of the Nervous System
- The brain has three major functions: controlling behaviour, processing and retaining information
we receive from the environment, and regulating the body’s physiological processes.
- Brain needs to receive information from the body’s sense receptors, and it must be connected with
the muscles and glands of the body if it is to affect behaviour and physiological process; the brain
cannot act alone.
- Nervous system consists of two divisions:
- Central Nervous System: which the brain and spinal cord make up.
- The spinal cord is a long, thin collection of nerve cells attached to the base of the brain and
running the length of the spinal column.
- The spinal cord has a circuit of nerve cells that control some reflexes (i.e. moving your hand away
when it gets burned).
- The central nervous system communicates with the rest of the body through nerves – bundles of
fibres that transmit information in and out of the central nervous system.
- The peripheral nervous system is made up of the nerves that connect the spinal cord to the
base of the brain.
- Sensory information (about the internal and external environment) is conveyed from sensory
organs to the brain and spinal cord.
- The cranial nerves send information from the head neck region to the brain.
- Sensory information from the rest of the body reaches the spinal cord (and ultimately the brain)
through spinal nerves.
- These two types of nerves also carry information to the central nervous system.
- The human brain has three major parts: brain stem, cerebellum, and the cerebral hemispheres.
- The brain stem is one of the primitive regions of the brain, and its functions are correspondingly
basic ones: primarily control of physiological functions and automatic behaviours.
- The pair of cerebral hemispheres constitutes the largest part of the brain.
- This part of the brain contains the part of the brains that evolved most recently – and thus are
involved in behaviours of particular interest to psychologists.
- The cerebellum (attached to the back of the brain stem) looks like a miniature version of the
cerebral hemisphere. Its primary function is to control and coordinate movements.
- The brain is encased in the skull, and the spinal cord runs through the middle of a column of hollow
bones known as vertebrae.