Biopsychology Flashcards
What are the two components of the nervous system?
Central Nervous System (CNS)
Peripheral Nervous System (PNS)
What is the human nervous system?
Complex network of nerve cells that carry messages to and from the brain and spinal cord to other parts of the body to communicate with each other.
What is the CNS split into?
Brain
Spinal cord
What is the PNS split into?
Somatic nervous system
Autonomic nervous system
What is the autonomic system then split into?
Sympathetic NS
Parasympathetic NS
What is the nervous system and what does it help do?
network of nerve cells carrying messages to and from the brain and spinal cord to different parts of the body.
What does the CNS do?
Receives information from the senses and controls the body’s responses
What is the Peripheral nervous system?
Part of the nervous system that is outside of the brain and spinal cord
What is the brain responsible for?
Coordinating sensation, intellectual and nervous activity
What is the spinal cord?
Bundle of enclosed nerve fibers which connect nearly all parts of the body with the brain through spinal nerves.
What is the voluntary and conscious control system?
Somatic nervous system
What does the somatic nervous system contain?
Contains sensory + motor nerves that control skeletal muscles like joints. Typically receive and act on external stimuli.
What is the autonomic nervous system and what does it contain?
Unconscious thought.
Contains nerves that control heartbeat.
Adjusts and maintains body’s internal environment
What is the parasympathetic nervous system responsible for?
Calms the body after an emergency state.
What is the parasympathetic nervous system involved in?
energy conservation and digestion
What is the sympathetic nervous system involved in?
Responses that help us deal with fight or flight
Where is the relay neuron found?
In the CNS
What does the relay neuron allow
Communication between motor and sensory neurons
What are sensory neurons? and what do they do?
They carry sensory receptors to spinal cord / brain. Sensory neurons convert info from receptors into nerve impulses. When impulses reach brain they are translated into sensations (eg: heat) so organism can react appropriately
What are motor neurons? and what do they do?
Form synapses with muscles and control their contractions. Motor carries relay neuron to allow the muscle to then contract.
What are the two types of neurotransmitters?
Excitatory and inhibitory
What is an exitatory neurotransmitter? and give an example.
Nor-adrenaline.
Excitatory neurotransmitters are the system’s ‘on switches’ which increase the likelihood of an excitatory signal being sent to the post synaptic cell which is then more likely to fire.
What is an inhibitory neurotransmitter? and give an example.
Serotonin.
Nervous system’s ‘off switches’ which decrease the likelihood of neurons firing. Generally responsible for calming mind, body and inducing sleep.
What is the name of a junction between two neurons?
A synapse.
What happens when an impulse reaches the end of a neuron? Describe synaptic transmission.
Causes a neurotransmitter to be released into synaptic cleft. Neurotransmitter then diffuses across post synaptic membrane before binding to receptor cells, relaying the message.
What is the pituitary gland controlled by?
Hypothalamus.
What do the endocrine glands do?
They produce and secrete hormones. They are chemical substances that regulate activity of cells or organs in the body.
What are the 5 glands?
Pituitary Adrenal Hypothalamus Ovaries Testies
What does the endocrine system do?
Regulated by feedback similar to how a thermostat regulates temperature in a room. Signal sent from hypothalamus to pituitary gland in form of a ‘releasing hormone’ causing the pituitary gland to secrete a ‘stimulating hormone’ into the bloodstream. Hormone signals target gland and as levels of the hormone increase, hypothalamus shuts down secretion of stimulating hormone.
What are hormones?
Chemicals circulating in bloodstream and they are carried to target sites throughout the body. The come into contact with most cells but only affect those known as target cells - are able to respond as they have receptors for that hormone.
What is the pituitary gland?
Master gland. As hormones are released by P.G the hormones control and stimulate the release of hormones from other glands in the endocrine system.
What is the pituitary gland divided into?
Anterior (front) + posterior (rear)
What does the anterior pituitary gland do?
Releases ACTH as a response to stress - ACTH stimulates adrenal glands to produce CORTISOL.
Also produces LH and FSH - sexual characteristics.
What does the posterior pituitary gland do?
Releases OXYTOCIN, which stimulates contraction of uterus during childbirth. Also important for mother-infant bonding.
Describe the adrenal glands and where are they located?
2 of them sit on top of kidneys.
Outer part of each gland = adrenal cortex
Inner region of each gland = adrenal medulla.
Difference is that hormones released by adrenal cortex are necessary for life whereas adrenal medulla hormones are not.
What hormones are produced by the adrenal glands?
Adrenal cortex produces CORTISOL.
If cortisol level is low, individual has a low B.P, poor immune system and an inability to deal with stress. Tf adrenal cortex produces aldosterone responsible for maintaining blood volume + B.P.
Adrenal medulla releases adrenaline and noradrenaline, hormones preparing body for fight or flight.
What does nor adrenaline do?
Constricts blood vessels, causing blood pressure to increase.
What does the amygdala do in fight-or-flight responses?
The part of the brain that is triggered in fight-or-flight responses. Associates sensory signals with emotions associated with fight-or-flight such as fear.
How does the amygdala communicate with the hypothalamus in the fight-or-flight response?
Sends a distress signal to hypothalamus which then communicates to the rest of the body via the sympathetic NS for a response.
What are the two major stress reponses? and their meanings..
Acute (sudden) stressors such as a personal attack.
Chronic (ongoing) stressors such as a stressful job.
What does the SNS then do after hypothalamus has called it because of the amygala? and then what does the adrenaline do?
Adrenaline Sends signal to adrenal medulla to release adrenaline into blood.
Circulates body, affecting target cells, heart beats faster to push blood to the muscles and heart. Blood pressure and breathing rate increases. Release of glucose + fats to provide supply for energy
What does the PNS do after the fight-or-flight response?
Once the threat has gone, autonomic nervous system dampens down stress responses causing a decrease in heart rate and blood pressure and digestion begins again.
How does the brain respond to chronic stressors?
If brain continues to perceive something threatening the second system kicks in. Hypothalamus activates the HPA axis.
What does the abbreviation HPA stand for?
Hypothalamus
Pituitary gland
Adrenal glands.
What does the H P A axis do?
Hypothalamus - stimulates (CRH) into the blood.
Pituitary gland - CRH causes pituitary to produce + release ACTH targetting cells in adrenal glands
Adrenal gland - ACTH stimulates adrenal cortex to release various stress hormones including cortisol causing a positive effect - a burst of energy.
What is the ‘tend and befriend’ evaluation point in fight or flight response
Taylor et al (2000) suggests for females, responses to stress are due to tend and befriend than fight or flight.
Involves protecting themselves/young ones through nurturing behaviours (tending) and forming protective alliances (befriending).
They may have a different strategy to coping with stress because of the context of being the caregiver of the child.
What are the negative consequences of the fight or flight response - eval point.
Stress of modern life rarely require such levels of physical activity - problem arises when response is repeatedly activated eg: increased B.P, a characteristic of SNS activation can lead to physical damage.
Fight or flight does not tell the whole story - eval point.
Gray (1988) aruges first phase of reaction to a threat is not to fight or flee but to avoid confrontation - animals often display ‘freeze responses’ - not included.
What is localisation of function?
Localisation of function means that specific functions (language, memory, hearing, etc) have specific locations within the brain.
What is the motor cortex’s primary function?
Responsible for generation of voluntary motor movement.
Where is the motor cortex located in the brain? (what does each bit control?)
Frontal lobe in both the left and the right hemisphere - With the motor cortex on one side of the brain controlling the muscles on the other side of the body.
What is the somatosensory cortex’s primary function?
Detects sensory events arising from different regions of the body