biological key terms

biopsychology

study of natural processes of living things + scientific study of the way the mind works and influences behaviour

Aristotle

350BC said heart was crucial for behaviour and feelings

Hippocrates

(4th century BC) argued thoughts, feelings and behaviour originate in the Brain

plato

4th century BC- argued head and brain is our source of reason

monism

mental states and consciousness etc are viewed as emerging or reducible to physical brain processes

dualism

Descartes- mind is non-physical subject distinct from body’s physical substances

Phineas Gage

1848- railroad foreman who survived brain trauma, removing most of his left frontal lobe. saw significant personality change- became very rude and violent

Golgi

made a pigment that stained cells in the brain- saw the hippocampus neuron and then developed reticular theory- 1873

reticular theory

the brain is one single but complex network

Cajal

drew Purkinje cells by staining parts of human tissue and understood cells very separate entities that communicate with eachother 1889

Otto Lowei

1873-1961. electrically stimulated vagus nerve and found it slowed down heartbeat showing chemical communication’s importance in the body

Sherrington

coined the term synapse from the greek meaning together and to function

axodendritic synapse

synapse within the dendrites that can occur in the dendrites smooth surfaces or on the spines

glutamate

one of 2 main neurotransmitters in synaptic communication.
has excitatory effects via Na+ (AMPA) and NMDA (Na+ and Ca2+) receptors

GABA

has inhibitory effects via Cl- receptors

DSM-V-TR substance use disorder

outlines 10 categories of drug and 4 for use- risky use, social problems, impaired controlled and physical dependence. symptoms must be within 12 months and there are 3 stages of clinical severity

dependence

physiological adaptations due to chronic drug exposure, withdrawal symptoms

addiction

compulsive drug seeking and use despite consequences. dependence is not a necessary part of addiction. the behaviours

initiation- maintenance- abstinent - relapse

4 stages of addiction

mesolimbic dopamine system

VTA-V5. reinforces reward pathways in the brain assigning hedonic value to stimuli

expected reward

dopamine fires when you see the cue not when the reward is given

unexpected reward

dopamine neurone when the reward is given and appears

dopamine self-stimulation - Fibiger et al 1987

implanted electrode into VDA in rats, they pressed a bar for stimulation. the more stimulation the more they pressed it. when a lesion was made higher up the pathway the pressing was reduced= influence of mesolimbic system and dopamine in drug seeking and addiction

incentive-sensitisation theory

Robison and Berridge. hedonic impact and incentive salience are reinforcing. during maintenance the wanting is more and the liking is reduced. hypersensitivity in mesolimic enhances incentive salience

conditioned place preference

Salti et al. 2015- rats spent more time in area previously associated with drugs showing influence of environment

0.72

heritability for cocaine addiction

0.39

heritability for hallucinogens

monoamine oxidase A

breaks down neurotransmitters inc dopamine. lower levels correlate to higher addiction because reward signals feel stronger for longer

nicotine

effects CNS in less than 7 seconds. causes alertness, euphoria and relaxation. binds to neuronal nicotinic acetylcholine receptors found in basal ganglia, thalamus, hippocampus and cerebral cortex

nicotine withdrawal

irritable, restless, hunger, memory deficit. negative symptoms increase craving leading to relapse.

bupropion

helps 1in5 stop and maintain it. helps withdrawals but there are side effects like headaches, insomnia and anxiety

varenicline

binds to receptors the same way nicotine does so blocks it and it reduces pleasurable experiences of smoking. doubles chances of quitting in 6 months

nicotine replacement therapy

binds the same way and aims to slowly reduce dosage and withdrawal cravings. increases rate of quitting by 50-60%

structural MRI

uses difference in tissue rather than differences in BOLD signal to understand anatomy of the brain

functional MRI

uses magnetic fields to estimate oxyhemoglobin and deoxyhaemoglobin in different places due to different magnetic properties. show what areas are being used as they require more oxygen

BOLD signal

blood oxygen-level-dependent signal. measuring of oxygen in the blood in active areas. measured in volumetric pixels

hemodynamic response function

more activity there is the higher the BOLD signal

initial dip

in the HRF. there’s a small rise in deoxyhaemoglobin as the neurons consume oxygen so BOLD signal is reduced

over-compensation

in response to increased oxygen consumption, blood flow increases. more oxygenated blood than needed is delivered which is measured in the fMRI, BOLD signal increase

undershoot

blood flow and oxygen consumption dip and then return to initial level

positive emission tomography

radioactive tracers are injected into the bloodstream. the greater the blood flow the greater the signal emitted by the tracer. useful for targeting specific processes as you can use a tracer which binds to specific receptor sites otherwise temporal and spatial resolution are low

functional near infrared spectroscopy

sends light of particular wavelength into the brain. the light is scattered by oxy and deoxyghaemoglobin as both are sensitive to different wavelengths. the extent to which they are scattered estimates the BOLD response

can only measure cortical activity near the scalp

electroencephalography

skull cap with electrodes placed on patient, it records electrical signals. best temporal resolution. poor spatial resolution

event related potentials

averages EEG data to form a meaningful waveform, with no background nouse

transcranial magnetic stimulation

rapidly changing, powerful current passed through a coil wire near the head. the resulting magnetic field passed through the scalp and skull this induces a current in nearby tissue exciting or suppressing neurons

transcranial direct current stimulation

low intensity current delivered to and through the brain. a positive cathodal current facilitates some behaviours and a negative one inhibits behaviours

somatosenses

provides information about the body’s surface and internal state

cutaneous senses

provides info from surface of the body. they respond to pressure, vibration, heating, cooling and pain

proprioception

provide unconscious info about location of the body in space

kinesthesia

provide info about movement of the body

organic senses

provides info from, in and around internal organs

mechanoreceptors

detect vibration in the skin or changes in pressure

high-threshold mechanoreceptors

free nerve endings that respond to intense pressure e.g pinch

nocioreceptors

free nerve endings that respond to heat extremes

flavour vs taste

taste is sour, umami, salty, bitter, fat, sweet. flavour is made of olfaction and gustation

gustatory pathways

carries taste signals from tongue via cranial nerves to thalamus, then to primary gustatory cortex for conscious taste perception.
It is represented ipsilaterally (same side of the brain) and also integrates temperature, touch, pain, and different flavour patterns.

olfactory mucosa

tissue at the top of nasal cavity where odourous molecules are dissolved stimulating receptor molecules on cilia. less than 10% of air entering nostril reaches here

339

number of odour receptors that allow discrimination and identification of 10k odours

high frequency

= more cycles= higher pitch

higher amplitude

louder volume

phase

a specific point in a sound wave

sine wave

continuous wave, the compression is the same as the refraction

complex sound

average of several simple sounds

timber

distinct quality or uniqueness of a sound

hertz

number of cycles per second in a wave there are- frequency

pinna

collects and focuses sound like a funnel- in outer ear

auditory canal

sound is channeled into here by the pinna -in outer ear

ear drum

middle ear. aka tympanic membrane. it vibrates moving the malleus, incus and stapes (small bones in the ear) and the oval window.

cochlear

in the inner ear. spiral shaped bone structure which fills with fluid containing hair cells for converting mechanical sound into electrical signal

scala

fluid filled chambers in the cochlea. vestibule, media and tympani

organ of corti

in the cochlea. receives different pitched frequency vibrations

basilar membrane

vibrates and tunes sounds to different frequencies .

phase locked

certain neurons are only available for certain pitches meaning were good at discriminating sounds

hair cells in the cochlea

convert mechanical vibrations into neural signals

rhythm

pattern of timing between sounds. involves beat extraction, temporal pattern detection, prediction and motor coordination.
beat- pulse
meter- hierarchal organisation of bear e.g. 4/4 time

basal ganglia

in rhythm is responsible for internal timing, beat perception and movement initiation

cerebellum

role in rhythm is fine temporal precision and making millisecond level timing adjustments

social synchronisation

collective rhythm. as people drum together their oxytocin levels rise, neural oscillators align and hr synchronises. explains group cohesion

intramural time difference

sound directly yo the side of a person will reach the closer ear 700 microseconds before the other

medial superior olive

a subcortical structure which maps sound location

cornea

protective outer layer of eye, it is curved to bend light into the eye

iris

coloured part, muscles which open and close the pupil

lens

clear and flexible, can change shape to focus light onto the retina

pupil

hole in the centre of the iris. the iris can change its size to allow more or less light in

retina

clear lining at back of eye containing photoreceptor cells

optic nerve

carries info from the retina to the brain

photoreceptor cells

in the retina, they convert light into electrochemical signals (action potentials_

ganglion cells

receive visual info from photoreceptors via bipolar and amacrine cells. they have axons which extend into brain and form optic Neve, chiasm and tract

optic nerve blind spot

there are no photoreceptor cells here. info from other eye is used to make up for each eye’s blind spot

magnocellular pathway

receives input from rods, carries low spatial frequency info quickly- for movement and depth perception, top 4 layers of LGN

parvocellular pathway

receives input from cone receptors. carries high spatial frequency info slowly- for colour and fine details , bottom 2 layers of LGN

lateral geniculate nucleus

receives info from opposite visual field via axons from optic tract then projects info to primary visual cortex

ganglion cells- optic nerve- optic tract- LGN

order of vision in optic area

ventral stream

implicated in object individuation and form representation- the ‘what stream’

dorsal stream

the ‘where stream’ is implicated in guiding actions such as reaching or grabbing

glaucoma

build of pressure in the eye if fluid can’t drain. the base of the optic nerve is damaged by high pressure, causes tunnel vision

macula degeneration

macula contains the fovea and has high level of receptors. caused by damage by blood vessels or thinning of the retina with age

acquired prosopagnosia

facial recognition problems following brain injury and damage to fusiform face areas

congenital chromatopsia

caused by problems with functionality of cone receptors. colour blindness

cerebral chromatopsia

colour blindness caused by damage to V4