Human Nervous System
CNS
- Brain
- spinal cord ( sends motor commands to the body and sensory information to the body) (spinal reflex - basic behaviours)
PNS nerves
- autonomic (smooth, involuntary)
- sympathetic (stress response, fight or flight)
- parasympathetic (day to day functioning)
- somatic (skeletal, voluntary)
Frontal Lobe
- speech
- abstract thought
- planning
- social skills
Primary Motor Cortex
Movement of skeletal muscles
Parietal lobe
- touch
- non verbal thought
- spatial orientation - primary somatosensory cortex
- processing sensation
Temporal lobe
- hearing
- language
- Visual recognition
- understanding speech - primary auditory cortex
Occipital Lobe
-vision - primary visual cortex
Hippocampus
- Transfers declarative information to cerebral cortex for permanent storage - processed through low wave sleep
- Links emotion to memory, hippocampus (explicit memories) with amygdala (implicit memories)
- Functioning disrupted by stress, anxiety, depression, and PTSD (brain + head injury also)
Processing Language
Broca’s Area
- left frontal lobe - speech production
Geschwind’s Territory
- connection between two locations
Wernicke’s Area
- left temporal lobe - interpreting language
Voluntary Movement
Primary Motor Cortex
- Rear frontal lobe - movement of skeletal muscles
Basal Ganglia
- gathers information necessary to move - current position - complete feedback loop
Cerebellum
- midbrain - stores sequences of movements (learnt), co-ordinates + integrates
contralateral organisation - left controls right + vice versa
Emotion
Limbic system - implicated in memory, emotion, behaviour and motivation
- amygdala
fear, perceiving negative emotions, processing emotion,
memory recollection + storage
- hypothalamus
regulation + expression of emotions, emotional memory recall
- midbrain
reaction to stress, basic survival - running, fighting,
reproduction
GABA
gamma-aminobutyric acid
- inhibitory
- 1/3 of all neurons in the brain use GABA
- important in regulating anxiety
- arousal + sleep + anxiety
Neurotransmitters
chemicals the help communication across nerve synapses (synaptic transmission - process of neurons sending information via neurotransmitter.)
excitatory neurotransmitters
- causes neurons to fire ‘excites’ the target cell and causes more action potential.
inhibitory neurotransmitter
- inhibits neurons from firing, causes less likelihood of action potential.
Glutamate
excitatory neurotransmitters in the brain involved in learning
Acetylcholine
-neurotransmitter in the brain, spinal cord and PNS
- stimulates muscle contractions
- involved in learning memory
- controls REM sleep
- neuroplacticity
Alzheimer’s disease
- Gradual, severe memory loss
- confusion
- impared attention
- disordered tinking
- depression
- anterograde + retrograde amnesia
Causes:
LOW ACETYLCHOLINE
- amyloid plaques
proteins form along axon terminals + interfere with neuron’s
communication
- atrophy in hippocampus
Treatment:
- replace/increase acetylcholine
- prevent breakdown
Epinephrine (Adrenalin)
hormone + neurotransmitter
- secreted by adrenal glands
- involved in stress responses, fight, flight, freeze/ anxiety, fear,
emotional arousal
Causes increased:
- blood pressure
- heart rate
- respiratory rate
Dopamine
emotional arousal
- thoughts, feelings, motivations, behaviour - risk-taking, addiction
- experience of pleasure
- reward association (reward + pleasure centres)
release of glutamate into bloodstream - blood flows to muscles
- low levels = ADHA, hypertension + depression
Norepinephrine
hormone + neurotransmitter
- stress responses
- alertness + arousal
- emotion regulation + attention increases
Parkinson’s
- slowness of movement
- rigidity + involuntary movement
- difficulty stopping/starting movement
- reduced facial expressions
- pain, depression, dementia
Causes:
LACK OF DOPAMINE - degeneration of neurons in the basal ganglia
SN (responsible for movement) fires uncontrollably
- genetics, protein mutations
- environmental factors, pesticide robenone, MPTP (drugs)
- diet, vitamin B deficiency
Serotonin
-mood regulation
- social behaviour
- appetite + digestion, sleeping, arousal/sexual functioning, well-being/happiness
- aggression, antisocial behaviour, pain
Spinal Cord
connects PNS and brain to transfer information
Spinal reflexes
- monosynaptic reflex that serves a protective function
1 synapse, affector neuron (sensory), directly communicated
with effector neuron (motor)
- polysynaptic reflexes use two neurons: the affector, and effector
involving interneurons connecting affector and effector
neurons
Neurotransmission
Presynaptic - vesicle - axon terminal - receptors - post synaptic
LeDoux’s model of emotion
short route
- emotional stimulus - thalamus - amygdala - emotional response
long route
- emotional stimulus - thalamus - sensory cortex - amygdala/hippocampus - emotional response
