NEUROBIOLOGY

• Central nervous system

  Brain and spinal cord
• Peripheral nervous system

  somatic nervous system and autonomic nervous system
• autonomic nervous system

  Parasympathetic nervous system and sympathetic nervous system
• Diverging Neural Pathway

  Impulses from one neuron travel to several neurons so affect several destinations at one time.

  Eg allows fine motor control of fingers.
• Sympathetic (fight or flight)

  increases heart rate and breathing rate.

  Decreases peristalsis and production of intestinal secretions.
• Converging neural pathway

  Impulses from several neurons travel to one neuron.

  This increases the sensitivity to excitatory or inhibitory signals.

  Eg increases sensitivity to low levels of light summation allowing threshold to be met and signals travel to brain.
• reverberating neural pathway

  Neurons later in the pathway link back to earlier neurons, sending impulse back through the pathway.

  Allows repeated stimulation of the pathway.

  eg rhythmic actions like breathing
• brain consists of

  limbic system

  central core

  cerebral cortex
• cerebral cortex

  Controls conscious thought
• localisation of functions

  sensory - receives information

  Association - analyse and interpret

  Motor- send impulse to effectors
• Association areas

  involved in :

  Language processing

  personality

  imagination

  intelligence
• Corpus callosum

  Information is passed between the two cerebral hemispheres through the corpus callosum
• Split brain

  Left cerebral hemisphere deals with information from the right visual field and controls the right side of the body.

  Vice Versa
• Sensory memory

  lasts a few seconds and retains all visual or auditory input
• encoding

  sensory image converted into a form the brain can process
• storage

  retaining the information over a period of time
• retrieval

  Recovery of stored material from STM or LTM
• information is forgotten by..

  Displacement

  Decay
• Short term memory

  STM has a limited capacity of 5-9 pieces of information.

  These are retained for a short time.
• Serial Position Effect

  Items at the start of the list are remembered as they have had enough time for rehearsal.

  Items at the end of the list are remembered as they are still in the STM.

  Items in the middle of the list are forgotten as they have been displaced by items at the end of the list.
• Chunking


  STM can be improved by chunking.

  Dividing things into small chunks.
• ‘working memory model”

  STM can process data, to a limit extent, as well as store it.

  Allows STM to perform simple cognitive tasks.
• Rehearsal

  Repeating information over and over.

  Regarded as a shallow form of encoding into LTM.
• Organisation

  Organisation into logical groups or categories makes it easier to transfer to LTM
• Elaboration

  Addition of further information or meaning which results in the information becoming more meaningful and interesting.

  Elaboration is regarded as a deeper form of encoding which leads to improved retention.
• Contextual clues

  Relate to the time and place where the information was initially encoded into the LTM
• Neurons

  Provide body with rapid communication and control.

  Conduct nerve impulses from one part of the body to another.
• dendrites

  Receive nerve impulses from another cell and send the impulse to the cell body
• cell body

  • contains nucleus and cytoplasm.
  • nucleus contains DNA required to make various proteins.
  • Cytoplasm contains ribosomes also important in protein synthesis.
• Axon

  single nerve fibre

  Carries nerve impulses away from cell body onto next neuron