Biopsychology Flashcards
Fight or flight definition -
Sequence of events that occur in the body which occur due to the body needing to defend itself by attacking (fight) or flee situation (flight).
What are involved in the fight or flight -
Amygdala, pituitary gland and the hypothalamus.
Amygdala and hypothalamus coordination -
When there is a perceived threat the amygdala is stimulated
Sends distress signal to the hypothalamus communicates with the rest of the body though the sympathetic NS. (Prepares the body)
Acute (sudden stressors) - SNS
Begins preparing the body for rapid action of fight or flight, SNS sends a signal through to the adrenal medulla which responds by releasing adrenaline into the bloodstream. The SNS is connected via the hypothalamus.
Adrenaline in acute stressors
Comes from the adrenal medulla
Also releases noradrenaline
Adrenaline results in a number of psychological changes by pushing blood to working muscles, triggers the releases of glucose increases blood pressure.
The PNS in the acute stressors -
When the threat has passed the PNS is activated and results in a dampened down response reducing the effects of heartbeat and blood pressure and results in glucose being stored. (Rest and digest)
Chronic stressors -
HPA axis where the brain continues to perceive something as a threat
HPA axis is what -
Secondary system kicks in, the hypothalamus activates a stress response system called the HPA axis.
The HPA axis -
Order of events
H - Hypothalamus - relies on hormonal signals to keep the SNS working, in response to a continued threat releases CRH in response to the stressor.
P - The CRH arrives at the pituitary gland to release ACTH where it is transported down to the target site of the adrenal glands.
A - ACTH stimulates the release of stress related hormones such as cortisol which allow some sudden changes in the body suitable for fight or flight of quick bursts of energy and a lower sensitivity to pain.
Motor cortex -
Located in the Frontal lobe generated voluntary motor movements, both hemispheres have a motor cortex and controls muscle on the opposite side of the brain.
Somatosensory cortex -
Located in the Parietal lobe and is involved in the processing of different sensory events rising from different parts of the body produces sensations of touch, pressure, pain and temperature which is then localised to different areas of the body.
Broca’s area -
Language centre in the frontal lobe and is related to speech production. Broca found this evidence from studied patients.
Wernicke’s area -
Area in the temporal lobe which is used in the understanding of language. Shortly discovered after the discovery of the Broca area.
Circadian rhythm -
A pattern of behaviour that occurs or reoccurs every 24 hours like the sleep-wake cycle. Biological rhythms.
Sleep-wake cycle -
- Dictates when we should be asleep and awake.
- Light and dark are external signals that when we need to sleep and are awake.
- Synchronised by the master circadian pacemaker the suprachiasmatic nucleus. (hypothalamus)
- Light provides the primary input to this system which set the body clock and act as photoentrainment.
- These light stimuli are sensitive within the eye and act as brightness detectors send messages to the SCN which coordinate the activity of the entire circadian rhythm.