Biopsychology Flashcards
Motor cortex
Back of frontal lobe in both hems
Controls volun behav
Left hem controls movement in right side v.v.
Damage = loss of fine control
Somatosensory cortex
Processes info e.g., heat, pressure and touch
In both hems separate from motor by sulcus
Each part = allocated area - some = m than one
Visual cortex
If seen in left visual field processed in right hem v.v.
In occipital lobe
Damage in left hem = blindness in right eye v.v.
Auditory cortex
Temporal lobes
Process auditory info
Perception of sounds in environment signal from a.c. to other areas to process high level info
Broca’s Area
Lang processing
Left hem
Found area for speech production
Damage = aphasia = slow laborious speech - lacks fluency
Wernike’s Area
Language comprehension
Did research into patients who could speak ok but lacked ability to understand & comprehend speech
Language = fluent but meaningless
Case Studies
Clive Wearing had procedural and semantic no episodic
Brain Scan Evidence
Peterson et al (1988)
Used brain scans to show Wernike’s area = active in reading task - did functions
Tulving et al (1994)
Revealed semantic and episodic = dif areas of pre frontal cortex
Neurological Study
Dougherty et al (2002)
Reported on 44 ppl w/ OCD had eingulotomy at post surgery follow up = 32 weeks 1/3 met criteria for positive response & 14% for partial response
Holistic Theory
Lashley
Removed areas of cortex (10-50%) in rats learning a maze & found isn’t 1 section that = m NB - need whole cortex
Plasticity
When brain = damaged & a func = compromised/lost rest of the brain reorgs self to recover func - suggests not stuck in order
CNS
Made of brain: cerebral cortex what allow high level functioning = 2 hems
Spinal cord: extension of the brain - reflex actions
PNS
Transmits messages to and from the CNS
Subdivided into ANS & SNS
ANS
Governs vital function e.g., breathing, stress, heart rate and digestion
Sub divided into sympathetic and parasympathetic
Sympathetic = fight / flight - increased heart rate = for action
Parasympathetic = returns to resting state = rest and digest - blood goes back to digestion
SNS
Controls muscle movement
Receives info from sensory receptors
Endocrine System
Controls vital function
Slower than NS = m effective = widespread
Done via glands - uses hormones as chemical messengers
Pineal Gland
Releases melatonin
Responsible for NB bio rhythms e.g., sleep wake cycle
Thyroid Gland
Releases thyroxine - metabolism
Testes
Testosterone
Male sex characteristics
Muscle growth
Ovaries
Oestrogen
Reproduction and menstruation
Pituitary Gland
Controls and stimulates hormone release in other glands
Controlled and stimulated by the hypothalamus
Adrenal Gland (medulla)
Adrenaline and noradrenaline
Fight / flight response
Adrenal Gland (cortex)
Cortisol
Stimulates glucose release = energy and immune system
Glands and Hormones
Behaviour as a result of hormones
Glands secrete into blood - helps growth etc can increase / decrease cell processes
Fight / flight
Stress response system = acute / chronic stressors
Co-ord by hypothalamus - detects threat
= arousal of the ANS - SNS - stress hormone - F/F - sympha adrenal medullary system (SAM) ANS - PNS - normal
SNS & SAM = sympathomedullary pathway
Physiological changes = arousal for f/f acute response = automatic
PNS & SNS = antagonistic
Behaviour not limited to 2 responses (f/f AO3)
Gray (1988) doesn’t take into account freezing = hyper vigilant until decide correct response
Doesn’t fully explain complied cognitive and biological factors
Doesn’t fully explain females (f/f AO3)
Taylor et al (2002) adopt a tend & befriend tactic = m likely to protect offspring and make alliances
F/f = limited bc doesn’t explain
M recent research = beta bias assumes women respond same as men
Fight / Flight negative impact on health
Modern life don’t need to run so high blood pressure and flow can damage heart and lead to heath disease
= maladaptive now
Motor Neuron
Short dendrites and long axon
Connect CNS to effectors in CNS
Control muscle movement
When stimulated release neurotransmitters to receptors on muscles - trigger response = movement
Relay Neuron
Short dendrites and short axon
Connect motor and sensory / other relay
In brain and spinal cord
Allow sensory and motor neurones to communicate
Fast reflex bypass brain
Sensory Neuron
Long dendrites and short axon
In receptors e.g., eyes, ears, skin
Carry nerve impulses to spinal cord and brain and translate to sensations e.g., vision
Don’t all reach brain some stop at spinal cord
Quick reflex action
Firing of a neuron
Resting neuron = negatively charged when activated by stimulus in cell =positively charged for split second
Action potential = passing through when positively charged allows electrical impulse to move through
Synaptic Transmission
Process = 1 neuron communicates with another and sends information down axon as an electrical impulse = action potential - when at end need to - to neuron / tissue
Process of Synaptic Transmission
Vesicles release neurotransmitters to synaptic cleft
Neurotransmitter binds to receptor and activate
Excess = taken up by presynaptic neuron
Enzymes released to breakdown remaining
Vesicles replenished with new and reused neurotransmitter
Neurotransmitters
Chemical messengers found in brain, spinal cord and some glands
Transmit sign, across synaptic cleft - communicates between neurons
Only certain ones fit receptors = specialised function
Excitation
Increased likelihood of something happening
E.g., adrenaline causes excitation - increases neurons positive charge makes firing m likely
Inhibitation
Decreased likelihood of something happening
E.g., serotonin inhibits neighbouring neurons = - charge = less likely
Summation
Effect of neurotransmitters at synapse depends on number of factors:
1. How much = released
2. Action on postsynaptic neuron e.g., E/I - brings closer/further from AP threshold
Inputs at same time add together if E trigger AP and transmission of nerve impulse = summation
Temporal: 2 / m APs arrive in rapid succession along single presynaptic neuron and add together
Plasticity
Brains apparent ability (in infancy) to change & adapt physically & func
In infancy brain grows - peaks 15,000 synaptic connections at 2-3 (Gopnick 1999) = 2x adult brain
Originally thought that brain moves out of critical period & changes stop
Now think learning and experience changes the brain
Synaptic Pruning
As we age unused connections = deleted and used = strengthen
Maguire et al (2000)
Aim: investigate func of hippocampus in spatial memory
Ptps: 16 male London TD’s comp to MRI scans of 50 male non TDs
Hippocampus = bigger in TDs & volume = correlated w/ time as TDs
Function Recovery
After physical injury / trauma e.g., stroke unaffected areas comp for damage = ex of plasticity
Healthy areas take over damaged roles
= quick at start and then slows
Axonal Sprouting
Growth of new nerve endings to connect w/ undamaged nerve cells
Form new neural pathway can unmask neural pathways
Reformation of Blood Vessels
Blood vessels = refed to ensure brain funcs in affected areas