Biological Influences Flashcards
The nervous system
A communication system that controls all parts of the body
Central nervous system
The integration and control system of the body
Brain responsibilities?
- cognition, mental processes + bodily functions
- registers stimuli
- interprets
- responds w/ effector cells
Sympathetic NS
- fight/flight
- controls HR
- operates when highly aroused/ need energy bursts
Peripheral NS
- made up of all other nerves connecting CNS to body
- connects brain + spinal cord to sensory receptors in sense organs responding to external stimuli
Neurons
Cells from basic chilling blocks of entire NS
Somatic NS
- subsystem, voluntary control via skeleton muscles
- afferent sensory neurons allow movement
Automatic NS
- controls involuntary functions (internal muscles, organs etc)
- regulates body functions
Parasympathetic NS abilities
- slowing/ calming
- rest/ digest
- maintains homeostasis
- no longer under threat
Increase blood flow to body
Frontal lobe function+damage
F: thinking, decision making, feeling + behaviour, movement.
D: language disabilities, personality changes, Voluntary movement issues
Parietal Lobe functions + damage
F: body sensations, ie touch temperature, pain, spatial awareness
D: math/reading/writing disabilities
Occipital Lobe functions + damages
F: vision, perception, colour recognition, integrates eye info to whole pictures
D: full/ partial blindness, hallucinations (drugs)
Temporal lobe function + damage
F: hearing, speech production + memory
D: hearing loss, speech failure, memory loss, inability to recognise faces
Primary visual cortex function + damage
F: visual. Eyes: perception + colour recognition
D: blindness, cortical rep. (Distortion if memory)
EG* Herman Munk (1881) made lesions on dog’s occipital loves and nursed back to health. Dogs see perfectly but familiar objects where unrecognisable
Auditory cortex ( top of temporal lobe )
F: auditory info received + processed, response then coordinated
D: loss of sound awareness, reflex reaction to sound were due to subcritical processing
Motor cortex
F: voluntary movement
D: impaired movement on opposite side of body to damage
Sensory cortex
F: Amount of cortex devoted depends on sensitivity, not size
D: decrease sensory threshold/ struggle to identify objects via touch
Broca (frontal lobe)
F: mouth+ tongue control. Production of speech, grammatical structures, enable clear+ fluent speech
D: understand language but can’t from words
Wernickes’s Area (left temporal lobe)
F: understand written/ spoken language
D: difficulty understanding words/ produce sounds, unable to locate words in memory, sentences= meaningless, nonsense may make sense to themselves only
Repeating a heard word cortex processes
1: activates Primary auditory cortex (hear)
2: wernicke’s area (remembers)
3: broca (creates speech)
4: motor cortex (responds w/ movement/words)
Neurons
A specialised cell that receives, transmits + processes info
3 types of neurons ?
- sensory (afferent)
- motor (efferent)
- inter (connector/relay)
Synapse process?
1- signal released when electrical msg reaches axon terminal
2- travel across synapse to next neuron’s dendrites
3- dendrites send signal to another neuron
4- neurotransmitters broken down/reabsorbed
Define membrane potential
The difference in electrical potential between the inside + outside of the neuron
Define polarised
Cell pumps ‘+’ ions through membrane, making cell more ‘-‘ than outside
Define depolarised
when ‘+’ ions fire @ full strength/not at all, a neuron decreases in polarisation (inside more than outside)
Define repolarised
when ‘+’ neurons pump outside membrane, cell returns to polarised state
4 neurontransmitters?
dopamine, serotonin, endorphine + norpinephine
dopamine responsibilities?
learning, attention, pleasure, sleep + wake cycles
serotonin responsibilities?
sleep, hunger, arousal, lifts mood, produces satiety. Links with depression. Drugs alter this NT
Endorphins responsibilities?
controls alertness, arousal + memory. Undersupply can cause depression
Serotonin increases positive mood inductions how?
music, light levels, exercise + diets
Low levels of Dopamine cause what?
schizophrenia, ADHD, Parkinsons etc. High amounts can cause addiction
Define genetics
The study of heredity + passing on inherited characteristics from 1 generation to the next
Define heredity
The passing of genetic characteristics from 1 generation to the next
Define nature
How much our differences are shaped by our geneitc codings
Define Nurture
How much are our differences shaped by our environment/upbringing
Synaptic transmission process? (3 steps)
1: reuptake into axon terminal, 2: enzymes break down NT into components to be reabsorbed, 3: drift away via diffusion
What is epigenetics?
modification to gene expression that doesn’t involve altering underlying genetic code. (inherited, genes activate/deactivate, changes phenotype, affects how cells read genes) eg, lactose intolerance
Bouchard + McGue (1981) meta analysis of siblings
Found closer siblings have more similar IQs. Generalisable study. difficult to differentiate nature/nurture influences
Bouchard et al. (1990) Minnesota Twin Study
Studies similarities in IQ of Identical twins reared together v apart. Compared ability, personality, attitudes, hobbies. 69% intelligence for twins raised apart. 88% accordance for together. 70% attributed to genetics. 30% nurture. Correlation does not =causation
Explain hormones
genes impact behaviour, thoughts + emotions via regulation + production of hormones. eg increased oestrogen influences behaviour.
Adrenalin effects
increase arousal, heart + breath rate, decrease pain response and slow digestive system. Difficult to concentrate + communicate
Noradrenalin effects
maintains blood pressure, increase blood sugar, alertness, anxiety + vigilance, breaks down fat for energy
Psychoactive drugs
SUBSTANCE THAT ACTS UPON CNS…Influence thoughts, feelings + behaviour. Hijack receptors + alter body chemistry.
Recreational drugs
makes us feel better, most medical, legal v illegal
Depressants…?
calm activity of the neurons and slow body functions
Stimulants…?
excite nervous system and arouse body functions
Hallucinogens
change perception + give sensory images w/o input from senses
Ecstasy is a?
stimulant + mild hallucinogen. Large risks= dehydration, overheating, eventual death
