Year 1 biopsych

• central nervous system CNS

  • made up of brain and spinal chord
  • functions: control of behaviour and regulation of the body's physiological processes -> brain sends messages to muscles and glands in the body
• spinal chord

  • main function: relay information between the brain and the rest of the body
• peripheral nervous system

  • somatic nervous system
  • autonomic nervous system
• autonomic nervous system


  ans has two parts: sympathetic and parasympathetic
• sympathetic nervous system

  • involve responses which help us deal with emergencies
  • increases heart rate, pressure and dilating blood vessels in muscles
• parasympathetic nervous system

  • relaxes an individual when an emergency has passed
  • slows the heart beat, reduces blood pressure
• hypothalamus

  • stimulates and controls the release of hormones from the pituitary gland
• pineal gland

  • releases melatonin
  • responsible for important biological rhythms including the sleep-wake cycle
• thyroid gland

  • releases thyroxine
  • responsible for regulating metabolism
• pituitary gland

  • sometimes known as the 'master gland' because the hormones released by this gland controls and stimulates release of hormones from other glands
• ovaries

  • releases oestrogen
  • controls the regulation of the female reproductive system including the menstrual cycle and pregnancy
• testes

  • releases testosterone
  • responsible for the development of male sex characteristics during puberty while also promoting muscle growth
• adrenal glands (medulla) (inner part)

  • releases adrenaline and noradrenaline
  • the key hormone in fight or flight response
• adrenal gland (cortex) (outer part)

  • releases cortisol
  • stimulates the release of glucose to provide the body with energy while suppressing the immune system
• pituitary gland 


  has two main parts: anterior (front) and posterior (back)

  • anterior releases ACTH as a response to stress and stimulate the adrenal glands to produce cortisol
  • posterior releases oxytocin which stimulates contraction of the uterus during childbirth
• motor neuron

  • cells are in the CNS, their long axons may be in the PNS allowing control of muscles
• relay neuron

  • relay neurons make up 97% of neurons - mostly in brain and spinal chord
• sensory neuron

  • sensory neurons are located in the PNS. send info to the brain. some neurons end in the spinal chord enabling reflex actions
• dendrites


  (branch like) carry nerve impulses from nearby neutrons toward the cell body
• nodes of ranvier


  gaps between myelin sheath are the nodes of ranvier - impulse jumps across these leading to increased speed
• myelin sheath


  covers and protects axon - speeds up electrical transmission of the impulse
• axon


  takes impulses away from the cell body towards the axon terminal
• cell body 


  contains a nucleus - the control centre of the neuron
• axon terminal (terminal buttons)


  communicate with the next neuron across the synapse via synapticc transmission
• hypothalamus (chronic) (HPA axis)

  1. releases CRH (corticoitophin - releasing hormone)
  2. activates pituitary gland
  3. causes release of ACTH stress hormone
  4. stimulates the outer edge of the adrenal gland called adrenal cortex
  5. allows production of glucocoricoids (glucose and cortisol)
• hypothalamus (acute) (sympathetic NS)

  1. activates the sympathetic branch of the ANS
  2. neuronal messages are sent to inner core of the adrenal gland called adrenal medulla
  3. results in secretion of adrenaline and noradrenaline
  4. fight or flight response
• A03 fight or flight

  • for females behavioural responses to stress are more characterised by a pattern of tend and befriend rather than fight or flight. Involves protecting themselves and their young through nurturing behaviours(tending) and forming protective alliances with women (befriending) - women have a completely different system for coping with stress because their responses evolved in the context of being the primary caregiver.
• A03 fight or flight 2

  • negative consequences of the fight or flight response - responses associated with fight or flight may be adaptive for a stress response that requires energetic behavioural responses - problem for modern humans arises when stress response is repeatedly activated - increased blood pressure can lead to physical damage in blood vessels and eventually to heart disease.
• A03 fight of flight 3

  • fight or flight does not tell the whole story - gray argues that first phase of reaction to threat is not fight or flight vut avoid confrontation. - most animals display 'freeze response' - initial freeze response is where animal is hyper- vigilant, alert to slightest sign of danger. adaptive advantage of this response is that humans freezing focuses attention and makes them look for new information to make the best response for that particular threat
• neurotransmitters

  • can be classified as either excitatory and inhibitory
• excitatory neurotransmitters

  • 'on switches' for nervous system
  • increase the likelihood that an excitatory signal is sent to postsynaptic cell which is then more likely to fire
• inhibitory neurotransmitters

  • nervous systems 'off switches'
  • they decrease likelihood of that neuron firing
  • responsible for calming the mind and body, inducing sleep and filtering out unnecessary excitatory signals