Biopsychology Flashcards
How is the nervous system arranged?
Nervous system: made up of Central and peripheral nervous system
CNS: Made of brain and spinal cord
PNS: made of somatic and autonomic nervous system
Autonomic: Made of sympathetic and parasympathetic nervous systems
What dos the CNS consist of
Brain and spinal cord
What is the brain
Centre of all conscious awareness.
Very developed in humans.
Split into 2 hemispheres
Contains only relay neurones
What is the spinal cord
Transfers messages to and from the brain and the whole body
Responsible for reflex arcs
Relay and motor neurones
What is in the peripheral nervous system?
The somatic and autonomic nervous system
What is the somatic nervous system?
What receptors and neurones does it have
Initiates muscle movement (doesn’t control)
Carries info from world to brain
Made of sensory receptors
Has sensory and motor neurones
What is the autonomic nervous system?
Has an important role in homeostasis (Involuntary functions).
Only contains motor pathways
What is the autonomic nervous system made of?
The sympathetic and parasympathetic nervous systems
What is the sympathetic nervous system?
Involved with fight or flight
Prepare us for action in dangerous situation e.g. increase HR
What is the parasympathetic nervous system?
Relaxes out body to its original state
It slows HR, breathing rate and reduces BP
Digestion is restarted
What is the process of synaptic transmission
Action potential causes vesicles to move towards pre synaptic membrane
Vesicle fuses to cell membrane releasing neurotransmitters
Neurotransmitters diffuse down conc. grad. to receptors in the post synaptic membrane
A new action potential is made in the next cell
Enzyme reuptakes the chemicals
What are the 3 types of neuron
Motor neurone
Sensory neurone
Relay neurone
How can you identify a Relay neurone? What do they do?
Rounder, lots of connections, Nucleus in the middle
They connect motor and sensory neurones together
Only in the CNS
How can you identify a Sensory neurone? What do they do?
Are shaped more like an S because the cell body sticks out from the axon
These respond to incoming information from any of your senses.
There are fewer connections to increase transmission speed
How can you identify a Motor neurone? What do they do?
Its not either of the others
It sends a message back to the body using a motor neuron.
What is a neurotransmitter
Chemicals released from synapses which travel from neurone to neurone
What is the synaptic cleft
The gap between the presynamptic membrane and post synaptic membrane
Name 3 neurotransmitters
Adrenaline - fight / flight
Dopamine - Pleasure
Serotonin - Mood
What are the 2 types of neurotransmitter?
Excitatory and inhibitory
What is an excitatory neurotransmitter? Name one
Acetylcholine
Nerone develops an excitatory post synaptic potential - it is more likely to fire - produces a positive charge in a cell
What is an inhibitory neurotransmitter? Name one
GABA
Neurone develops an inhibitory post synaptic potential - less likely to fire - generates a negative charge in the cell
What is summation?
If a nerve cells receives excitatory and inhibitory potentials at the same time, the sum of each decides if the neurone fires
What are the 2 types of summation
Temporal and spatial
What is temporal summation?
A large amount of excitatory post synaptic potentials are generated quickly increasing the chance of firing
What is spatial summation?
Many different excitatory post synaptic potentials are generated on the same neurone increasing the chance of it firing
Function of endocrine system
To secrete the hormones which are required to regulate many bodily functions.
To provide a chemical system of communication via the blood stream.
What is a gland?
An organ in the body that synthesises chemicals like hormones and releases them into the blood
What is a hormone?
A regulatory substance produced in the body and transported in blood / tissue fluid to stimulate cells
Name some things that happen when fight or flight is initiated
HR increases
BP increases
Digestion decreases
Lungs speed up
Muscles tense
Why do we have a fight or flight response?
An evolved reaction to perceived threat
To survive
What nervous system activates fight or flight
Sympathetic
What does the hypothalamus do?
Stimulates the release of hormones from the pituitary gland
What does the pituitary gland do?
Hormones released from the gland stimulate the release of hormones from other glands
What does the adrenal gland (medulla) do
Releases adrenaline and noradrenaline - important in fight / flight
What does the adrenal gland (cortex) do
Releases cortisol - stimulates the release of glucose but suppresses the immune system
Role of adrenaline
Increases blood flow to brain and muscles
Prepares body for action
Increases oxygen to brain for rapid response
What do the testes do?
Release testosterone - Responsible for the development of male sex characteristics during puberty, also promotes muscle growth
What do the ovaries do
Controls the regulation of the female reproductive system including the menstrual cycle and pregnancy
What does the thyroid gland do
Releases thyroxine - regulates metabolism
What does the pineal gland do
Releases melatonin - important for the sleep wake cycle
What are acute stressors?
Sources of stress that are short term. They require immediate attention
They may threaten survival
Our ancestors may have experienced them when facing a predator
What is the process of fight/flight beginning
Amygdala registers a threat and sends a signal to the hypothalamus
Hypothalamus activate the sympathetic nervous system
The sympathetic nervous system sends a signal to the adrenal medulla which releases adrenaline
The adrenaline circulates in the blood stream causing increased HR, BP, breathing etc
We are now ready to attack or run
What is a chronic stressor?
Long term stressors over weeks or months
What is the HPA axis
the bodies response to chronic stress
How does the HPA axis work
The Hpothalamus releases CRH into blood stream
The Pituitary gland is activated and releases a hormone targeting the adrenal gland
The Adrenal cortex releases the stress hormone of cortisol
Fight or flight evaluation
Human behaviour isn’t limited to just 2 responses - freeze (found by Gray)
Negative affects in the modern day e.g. increased BP and contribution to heart disease
Affects women differently e.g. tend (to children) and befriend (other women) found by Taylor
What is localisation of function
The brain is split into different areas controlling different functions
Based on phrenology
Phineas Gage case study
25 Year old
An explosive went off and catapulted a large iron rod into his head (frontal lobe)
Phineas survived but experienced large changes in his personality
This tells us the frontal lobe affects mood and personality
What is the frontal lobe involved with?
Emotions, decisions, concentration
Contains the motor cortex which controls voluntary movement
What is the parietal lobe involved with?
Back top of brain
Processing, orientation, sensory discrimination
Contains the somatosensory cortex which processes sensory info entering the brain