Bio Psych A

• Hypothalamus


  Regulates hunger, thirst, sleep and wakefulness plus most of your involuntary mechanisms including body temperature
• Thyroid glands


  Regulates your energy and your metabolism
• Pancreas


  • Aids in the digestion of protein, fats and carbohydrates
  • Produces insulin which controls blood sugar levels
• Ovaries


  Influences how your blood circulates and determines your mental vigor and your sex drive
• Pituitary gland


  • Controls all other endocrine glands
  • Influences growth, metabolism and regeneration
• Parathyroid


  Secretes the hormones necessary for calcium absorption
• Thymus


  Helps build resistance to disease
• Adrenal glands


  • Secretes hundreds of compounds including cortisone & adrenaline which helps you react to emergencies
  • Regulates your metabolic processes in the cells, water balance, blood pressure, etc.
• Endocrine system


  The conversion of nutrients into energy and building materials to meet your body's needs
• Metabolism is the conversion of nutrients into energy and building materials to meet your body's needs
• Fight or Flight


  A sequence of activity within the body that is triggered when the body prepares itself for defending or attacking (fight) or running to safety (flight)
• Fight or Flight response


  • Involves changes in the nervous system and the secretion of hormones that are necessary to sustain arousal
• Taylor (2000): ''Tend and befriend' - suggests that for females, behavioural changes to stress are more characterised by a pattern of tend and befriend than fight or fight. This involves protecting themselves and their young through nurturing behaviours (tend) and forming protective alliances with other women (befriend). Women may have a completely different system for dealing with stress because their responses evolved in the context of being the primary caregiver of their children.'
• Negative consequences
• Von Dawans et al (2012): 'Challenge the classic view that, under stress, men respond only with fight or flight, whereas women are more prone to 'tend and befriend'. Von Dawans et al's study found that acute stress can actually lead to greater cooperative and friendly behaviour, even in men. This could explain the human connection that happens during times of crisis such as the 9/11 terrorist attacks. One reason stress may lead to greater cooperative behaviour is because human beings are fundamentally social animals and it's the protective nature of human social relationships that has allowed our species to thrive.'
• Lee and Harley (2012): 'Have found evidence of a genetic basis for gender differences in the fight or fight response. The SRY gene, found exclusively on the Y chromosome in males, directs male development, promoting aggression and resulting in the fight or fight response to stress. They suggest the SRY gene may prime males to respond in this way by the release of hormones like adrenaline. The absence of the SRY gene in females (who don't have a Y chromosome), together with the action of oestrogen and oxytocin, may prevent the stress response.'
• Adrenaline has a strong effect on the cells of the cardiovascular system, stimulating the heart rate, contracting blood vessels and dilating air passages
• Adrenaline also stimulates the release of blood sugar (glucose) and fats which food into the bloodstream supplying energy to parts of the body associated with fight or flight
• The release of hormones

  1. Gland is stimulated

  2. Relevant hormones released into bloodstream

  3. Hormone binds to specific receptors in target cells

  4. Triggers a response
• Oxytocin


  Hormone released by the pituitary gland, important for reproduction behaviour
• Oxytocin is released following orgasm, which aids conception and elicits a feeling of relaxation and calm
• High levels of oxytocin encourage a strong bonding between couples, as well as between mother and child
• Direct effects of Adrenaline

  • Increase heart rate
  • Constrict blood vessels, increasing rate of blood flow and raising blood pressure
  • Divert blood away from the skin, kidneys and digestive system
  • Increase blood to brain and skeletal muscle
  • Increase respiration and sweating
• Indirect effects of Adrenaline

  • Prepare the body for action, fight or flight
  • Increase blood supply/oxygen, to skeletal muscle for physical action
  • Increase oxygen to brain for rapid response planning
• Dendrite


  Receives messages from neurotransmitters
• Axon


  Sends info as electrical signals
• Myelin Sheath


  Helps prevent signals from degrading. Helps speed of electrical conduction down the axon allowing faster action.
• Node of Ranvier


  Allows for rapid conduction of nerve impulses
• Cell Body


  Contains DNA genetic info
• Glial Cell


  Regulates nerve firing rates
• Action Potential


  Explosion of electrical impulses
• Synaptic Transmission


  1. Nerve impulses carried across the synapse between one neuron and another

  2. Signals within neurons transmitted electrically

  3. Signals between neurons transmitted chemically
• Presynaptic Neuron


  • Has a swelling called the synaptic knob
  • Contains synaptic vesicles filled with neurotransmitters
• Synaptic Transmission


  1. Electrical impulse reaches end of neuron

  2. Causes neurotransmitters to be released into synaptic cleft

  3. Neurotransmitters diffuse across to postsynaptic membrane

  4. Bind to specific receptors

  5. Can trigger an electrical impulse to cause a response
• Synapse


  Gap between one neuron and another
• Neurotransmitters


  Chemicals released into the synaptic cleft
• Synaptic Vesicles


  Contain neurotransmitters
• Neuron


  Affects other neurons by releasing a neurotransmitter that binds to chemical receptors
• Effect on postsynaptic neuron

  Determined by the type of receptor that is activated, not by the presynaptic neuron or the neurotransmitter
• Activation of receptors


  Caused by a flow of ions causing action potentials in the dendrites