Psych Unit 3 sac 1

• • Role of Nervous system:  Send messages from various parts of your body to your brain, and from your brain back out to your body to tell your body what to do.
• Anatomy of a neuron:

  • Dendrites
  • Soma
  • Nucleus
  • Myelin Sheath
  • Axon
  • Axon terminal
• Role of Central Nervous system:

  • the brain and the spinal cord; processes and coordinates responses to sensory stimuli
• Peripheral Nervous System:

  • all the nerves outside of the central nervous system that carry messages between the central nervous system and muscles, organs and glands throughout the body
• Sympathetic NS:

  • Increases arousal, heart rate, adrenaline
  • Ready's body for quick response
  • Dominates when under threat
  • Fight-flight-freeze

  Parasympathetic NS:

  • Maintains homeostasis
  • Dominates during normal activities
  • Counterbalancing energising function
• Conscious response:

  • Response to sensory stimuli
  • Involves awareness
  • Voluntary reaction
  • Goal-directed reaction

  Unconscious response:

  • Does not involve awareness
  • Unintentional/cannot control
• Spinal Reflex:

  • an involuntary and unconscious response to a stimulus involving the spinal cord, which occurs without input from the brain
• Neurotransmitter:

  • a chemical produced by neurons that carries messages to other neurons or cells within the nervous system, including muscles, organs and glands
• Glutamate:

  • the main excitatory neurotransmitter in the nervous system, which is involved with learning and memory
  • Activates neural activity in the brain

  GABA:

  • the main inhibitory neurotransmitter in the nervous system, associated with anxiety, specific phobias and Parkinson’s disease
  • Slows down neural activity in brain
• Glutamates role in learning and memory:

  • Stimulates connection between neurons
  • released when a neural pathway associated with an experience is stimulated
• Antagonist:

  • Slows down affect of neurotransmitter

  Agonist:

  • Mimic effect of neurotransmitter
• Neuromodulators:

  • a subclass of neurotransmitters that alter the strength of neural transmission, by increasing or decreasing the responsiveness of neurons to neurotransmitter signals
• How does Dopamine work as a neuromodulator?:

  • When doing something you enjoy, dopamine is released
  • Is a multifunctional neurotransmitter with both excitatory and inhibitory effects involved in many CNS functions such as pleasure, movement.
• Seratonin:

  • an inhibitory neurotransmitter that also acts as a neuromodulator, influencing a variety of brain activities
• Synaptic plasticity:

  • specific changes that occur within the synapse, between neurons
• LTP: refers to the long-lasting strengthening of synaptic connections, resulting in enhanced or more effective synaptic transmission
• LTD: LTD is a long lasting decrease in the strength of synaptic transmission
• • Rerouting(Healthy nearby neurons creating alternative pathways when existing connections are lost through injury.)
  • Sprouting(Existing neurons forming new axon terminals and dendrites to allow new connections to be made.)
  • Pruning - Elimination of weak, ineffective or unused synapses (and therefore connections to other neurons).
• Stress is a psychobiological process; a state of mental, emotional and physiological tension in response to something that is perceived as challenging or threatening our ability to cope
• Stress as a psychobiological process:

  • Psychological: including feelings such as fear, excitement and thoughts such as 'I can't cope'
  • Biological: including physical responses such as increased heart rate and increased muscle tension
• Internal Stressor:

  • originates within an individual; can be both psychological and biological

  External Stressor:

  • Originates from outside an individual, such as an event or environmental extreme
• How does fight-flight-freeze influence acute stress?

  •  People in fight or flight tend to take action to avoid or confront danger
• Role of cortisol in chronic stress:

  • Cortisol allows the body to continue to stay on high alert over long periods of time
  • It predominately benefits us in times of chronic stress by:
  • • boosting our energy levels and increasing blood glucose levels
  • • heightening our alertness, increasing the brain’s use of glucose
  • • increasing the body’s ability to repair tissue
  • • diverting energy from non-essential bodily functions such as digestion, growth and reproduction
• Enteric NS:

  • a subdivision of the autonomic nervous system; it consists of nerve cells lining the gastrointestinal tract and controls the digestive system
• Gut-brain axis being bidirectional:

  • communication can occur in both directions, from brain to gut and gut to brain
• Vagus Nerve:

  • a nerve that connects the brain (central nervous system) to organs within the autonomic nervous system, via nerve fibres that directly link organs such as the lungs, heart, oesophagus and intestinal tract
• Gut Microbiota:

  • Digest the components of our food to provide their own nutrition while also simultaneously providing us with energy and nutrients. Gut microbiota are also involved in the production of some neurotransmitters, which can affect the concentrations of related neurotransmitters in the brain.
• • stress causes changes in gut microbiota and deficiencies in certain bacteria, which have been linked to anxiety and depression
• Gas Model:

  1. Alarm Reaction(Shock, Counter Shock)
  2. Resistance
  3. Exhaustion
• GAS: Alarm Reaction Stage:

  Shock:

  • Ability to cope is below normal
  • Acute stress response

  Counter Shock:

  • Ability to cope is initially below, but then rises above normal
  • Fight-Flight-Freeze response occurs
  • Adrenaline and cortisol released
  • Muscles tense, heart rate, breathing rate increases, pupils dilate.
• GAS - Resistance stage:

  • Ability to cope is well above normal, beginning to drop
  • Cortisol levels are highest
  • Increased energy
  • Immune system functioning impaired
  • Physical wear and tear
• GAS - Exhaustion:

  • Ability to cope is well below normal
  • Energy stores depleted
  • Increased susceptibility to several physical conditions
• GAS Model

  Strengths:

  • Predicts pattern of stress response
  • Identifies biological processes which occur during stress response

  Limitations:

  • Tested on rats not humans
  • Does not acknowledge Psychological processes in stress response
  • Does not account for individual differences in stress response
• Lazarus and Folkmans Model of Stress and Coping:

  1. Event Occurs
  2. Primary Appraisal(Does event matter, is it stressful?)
  3. If not stressful, it is either irrelevant or benign/positive then no stress
  4. If stressful, it is either harm/loss, threat or challenge
  5. Secondary appraisal, Are coping resources adequate(minimised stress), or in adequate(heightened stress)
• Primary appraisal:

  • when an individual determines whether a situation or event is significant to them and stressful or not

  Secondary appraisal:

  • when an individual considers the available resources and their own coping strategies, to decide the best way of dealing with a stressor
• Lazarus and Folkman:

  Strengths:

  • Acknowledges psychological causes of stress response
  • Accounts for individuals

  Limitations:

  • Difficult to generalise findings
  • Narrowly focuses on psychological
• Coping Strategy:

  • a method that we use to manage or reduce the stress produced by a stressor
• Coping Flexbility:

  • the ability to modify our coping strategies to adapt and meet the demands of different stressful situations
• High context specific effectiveness helps deal with stress because it relates directly to managing the specific stress.
• Exercise can be an avoidance strategy because we are not directly dealing with the stress, but it can also be an approach because it helps us clear our head.