Introduction to Bio Psych Exam Revision PDF

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Bio Psych Revision3A+B: NEURONS AND SYNAPSES- The Nervous Systemo Central vs Peripheral Nervous Systemo Function Regulate inner systems and organs  Analyse info from enviro and inside body (sensing, thinking, cognition)  Coordinate motor patternso Evolution of CNS Cephalisation: central ganglia ...

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Bio Psych Revision

3A+B: NEURONS AND SYNAPSES -

The Nervous System o Central vs Peripheral Nervous System o Function   

o

Evolution of CNS   

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o o o o

Diffusion – ion channel (charged)/ membrane (uncharged) Active transport – ion pump Electrochemical driving force Active potential: Na+ Ca+ vs K+

o o

Ions: cation (+) vs anion (-) Ion channels: gated ion channels VS ion pump VS leak channels

Microelectrode recordings of membrane potential Intracellular vs extracellular Microelectrode with conducting fluid Difference in potentials Unit: millivolt or milliampere Hodgkin & Huxley

Action potential generation o o o o o

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Cephalisation: central ganglia and brain in one end Dorsal chord in vertebrate Ventral chord in invertebrate

Ions Transport

o o o o o

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Regulate inner systems and organs Analyse info from enviro and inside body (sensing, thinking, cognition) Coordinate motor patterns

Resting potential -70mv Depolarisation Rising phase, overshoot (Na+ enters) Falling phase, undershoot (K+ leaves) Recovery phase

Ligand-gated channels

Signal transmission o Neuron     

o o o

Input zone = soma and dendrites Integration zone Conduction zone = axon Output zone Axon terminals

Synapses One directional (refractory) Signal over distance    

Leak channels/ ion pumps

Myelinisation - ↑propagation Saltatory conduction along Nodes of Ranvier – ↑speed Thick axons - ↑speed Neuroglia cells:   

o

Voltage-gated channels

Schwann cells – signal propagation Astrocytes – nutrients Microglia – immune responses

Neurotransmitter types:



ESPS vs ISPS

Temporal summation: duration Spatial summation: different neurons Post synapse activity o o

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o o -

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Chemical receptors: metabotropic receptors vs ionotropic receptors  Slower-acting VS faster-acting Electric receptors  Fast/ synchronisation (e.g., escape responses)

Action potential VS graded potential o Integration zone VS soma and dendrites o Voltage-gated VS ligand-gated ion channels o Depolarisation VS de/hyperpolarisation o Threshold VS no threshold o All or nothing VS vary in amplitude Brief History o Camillo Golgi: created the staining method o Santiago Ramon y Cajal: popularised the staining method and drew early images of neurons

4A: MEMORY

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Memory process o Hippocampus & cortical areas o Fear conditioning evidence with rats:  

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ERPF hippocampus at day 1 vs day 28 vs control after conditioning anesthetics, immediately after learning vs before retest

studying memory o stroke o lesions o optogenetics: light-sensitive ion channel (opsin) learning o non-associative learning  

 



habituation: response weaken with repeated exposure dishabituation: reinstated response with different stimuli e.g., Alysia withdrawing gills Perpetuates in LTM: retain for until 3 weeks VS Sensitisation

o

Associative learning   

Stimulus-response learning Law of effect: learn based on outcome Operant conditioning



Classical conditioning

  

Positive/negative reinforcement/punishment US UR NS CS CR (temporal) contingency

4B: MEMORY -

Basics o

o o o

Hebb synapses – increase strength synaptic transmission if repeatedly activated Synaptic plasticity – synaptic activity can change Hippocampus: declarative memories + navigation/ spatial memories Grid cells & place cells   

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Grid cell fire in a regular and hexagonal pattern Grid cells instruct place cells in the hippocampus Place cells fire at a specific spot

How synapses change… o Pre-synaptic change 

 

Gain control: release more NT per signal Temporal filtering: more NT with the same firing frequency Modulatory interneurons: axo-axonal synapses 

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Pre-synaptic facilitation/ depression: (ms)

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Short-term potentiation: (s to min)



o

o

o

Sensitisation – more synapses Habituation – less synapses Dendritic membrane – more receptors more sensitive Modulatory interneurons

Spatial learning o o

Morris et al. 1982 – water maze 1. Mutation of APP gene:

o

2. Hippocampus lesion before vs after training

  

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More sensitive dendrite/ more receptors

Long term memory o o

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Increase/ reduce NT release in STM  higher/ lower PSP

Post-synaptic change 

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Axonal ending of facilitatory neuron connects to axon of presynaptic neuron and influence NT release

reduction time in finding platform in water maze 1. Hidden platform, 2. Beacon, 3. Hidden platform Spatial memory VS working/ reference memory

Long-term potentiation o o

= a burst of intense repetitive stimulation for a few seconds  postsynaptic neuron highly responsive to the same type of new input for minutes – days Per Andersson (1966) rabbit’s hippocampus:  

o

Additional despoliation during repetitive stimulation increase postsynaptic neuronal firing

signal travelling pathways in hippocampus (tri-synaptic system)  

Prefrontal pathway  Mossy fibre pathway 



o o o o

Steps:

    

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Schaffer collateral pathway 

@ Prefrontal pathway NT: glutamate Depolarisation (not action potential)

AMPA: ligand-gated Na+ NMDA: blocked by Mg2+, influx of Ca2+, signalling cascade Low-medium Ca2+ Vesicles releasing AMPA  AP5 = NMDA antagonist  supress LT potentiation High Ca2+ CERB promoting dendrites growth  anisomycin & rapamycin = Protein synthesis blockers

structural changes in brain: environmental and natural o o o o o

larger hippocampus in London taxi drivers enrich environments  higher synaptic density in mice crossmodally recruitment in deaf and blind (sign language & Braille reading) aging temporal constraints on plasticity

5A: ELECTROPHYSICOLOGICAL RECORDINGS -

microelectrodes (single cell recording) o o

measure firing rates pros  

o

cons

o

example:  Quian Quiroga and colleagues (2005): Halle Berry cell



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direct and precise temporal and spatial resolution invasive and restricted use

EEG (sensors on scalp) o o o o o

Detects ESPS Measure changes in field potentials outside neurons Large group of neurons activated at the same time close to the scalp

1. Frequency of EEG signals 2. ERPs  

Average separately

N400  

o

Pros

Semantic processing – lexicon of words Elicit by semantically incongruent words – large discrepancies

  o

Cons  

o

Temporal resolution Non-invasive Spatial resolution Inverse problem  mathematical and bio-physical modelling techniques  fMRI more precise

Examples   

Measure sleep: REM & awake Cruise et al. (2011): 3/16 vegetative state patients activated motor areas associated with instructions EEG and epilepsy  Abnormal/ excessive synchronisation of post-synaptic potentials results in large amplitude waves  During or between seizures

5B: SENSORY SYSTEMS -

Brain Somatotopic mapping Reorganisation:  strings players (Elbert et al., 1995)  re-occupied cortical region for lost body part  larger when used more o Segregated fast vs slow adapting signals o Top-down vs bottom-up processing Interneurons o Afferent vs efferent o Monosynaptic reflex arc vs polysynaptic arc o First/ second/ third … orders Sensory receptors o Input zone, accessories structures, transduction, filtering input o Mechanoreceptors, photoreceptors, thermoreceptors, chemoreceptors, nociceptors o Spiking vs non-spiking receptors Hierarchy: o Sensory receptors, spinal cord, brain stem, thalamus, primary/ secondary/ association sensory cortex Adaptation o Sensory adaptation o Adaptation during stimulation o o

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6A+B: VISION AND HEARING -

Vision o

Cones and rods    

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(L) Red, (S) blue, and (M) green cones Fovea trichromats Deuteranopia – M & L on X chromosome

Visual functions  Upside down retinal images  Mach band effect   

Blindsight / cortical blindness (V1) geniculate striate pathway vs extrageniculate pathways 

 o

(on/off-centre) Bipolar cells (on/off-centre) ganglion cells  On/off at centre  excites  less/more glutamate  depolarises  ISPS/ ESPS metabotropic/inotropic glutamate receptors  Non-spiking vs spiking

Lateral Geniculate Nucleus (LGN) in thalamus  Magnocellular VS Parvocellular cells  

o

  

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Spectrally opponent cells = A visual receptor cell that has opposite firing responses to different regions of the spectrum. Response pattern: +L/-M and +M/-L

Eye movements     

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V1: striate cortex = primary visual cortex  L or R eye dominant  Orientation columns  Six layers V1: conscious visual, shape, position V4: what - ventral V5: where – dorsal

Colour: wavelengths 

o

Layer 1 & 2 = M: larger receptive field, faster, sensitive to motion, low acuity, no colour discrimination Layer 3-6 = P: smaller receptive field, slower, higher acuity, coloursensitive

brain 

o

retina  LGN V1 (most retinal projections) retina  superior colliculus  Lateral Posterior Nucleus  higher visual cortex (eye movement and attention)

Receptor fields  

o

Interconnected neurons inhibiting neighbouring neurons via bipolar and horizonal cells  mutual inhibition creates stronger contrast

Hearing

Saccade Smooth pursuit movement Optokinetic nystagmus Vestibulo-ocular movement Abnormal eye movement  Dyslexia: more fixating and shorter jum  Schizophrenia: don’t follow objects sm

o o o o o o o o o o o o

Auditory canal Tympanum (eardrum) Oval window of cochlea Basilar membrane: base vs top Tonotopic arrangement of hair cells Stereocilia Outer vs inner hair cells Dorsal vs ventral cochlea nucleus  Superior olivary nuclei   Sound-source location Inferior colliculi in dorsal midbrain  Medial geniculate nuclei Auditory cortex  Tonotopic mapping

1A+B: BRAIN -

3 main divisions of the brain o o o

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2 transport systems o o

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Forebrain – make decisions Midbrain – direct movements Hindbrain – maintain current state Central and peripheral nervous system Vascular system

Comparative sizes of brain regions Key terms o o o o o o o o

Soma Axon Grey matter – soma White matter – axons Gyrus (gyri) Sulcus (sulci) Fissure Cytoarchitecture

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Corpus callosum

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Four lobes

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Sulcus/ fissure

o o o o o o

Intercallosal transfer Frontal, parietal, occipital, temporal Central fissure Parieto-occipital sulcus Lateral fissure Longitudinal fissure

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fMRI Slices

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Brain coordinates

o o o o

coronal, axial, sagittal Superior/ dorsal Inferior/ ventral Anterior/ rostral

o o o -

Localisation (by Flourens) o o o

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Posterior/ caudal Medial (middle) Lateral (sides) Propagnosia – fusiform face area Conjoint activation across multiple functions Broca’s area

Hierarchical organisation in motor control o o o o

Primary motor cortex – direct control over movement Premotor cortex – planning and preparation Supplementary motor area – intergrade motor and other behaviour Cerebellum + basal ganglia – coordination and regulation

2A: fMRI -

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fMRI vs MRI strong magnet BOLD signal o Slow o Detects small changes in magnetic field o Measure magnetic properties of oxygenated and deoxygenated blood o No stable baseline 1. Design a task o Block design vs event related design  

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Long periods of alternating task/baseline performance  Predictable, ecological validity, practice effect, can’t separate trails by performance Different conditions randomly intermixed and occur close together  Temporal resolution, post hoc sorting, unpredictable, randomisation

o Experimental condition vs baseline condition 2. Collect data o 3x3x3 mm voxel 3. Pre-process data o High pass filtering - Remove low frequency oscillations such as scanner drift that introduce noise into your data. o Motion correction - correct for head movement o Slice time correction - 2-3 secs between first and last slice. Correct align slices in temporal plane o Co-registration - co-register functional and structural fMRI data to identify the activated brain area o Normalisation - Warp each brain into standardized brain from MRI o Spatial smoothing - Apply gaussian kernel to reflect how much contribution each surrounding voxel makes to the central voxel’s signal. Because neurons do not fire in isolation.

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4. Analyse data o Multiple regression in each voxel – determine effect of IV (conditions) on DV (brain activation) o Raw t-map o Correct for multiple comparisons to reduce type one error o Whole brain analysis VS region of interest analysis  Prior hypothesis, multiple comparison problem, generalisable vs no spatial resolution in inter-subject comparison, … 5. Interpret data o Low temporal resolution o Correlative

2B: BRAIN DAMAGE and TMS -

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Brain damage o neuropsychology  Causality  Rarely anatomically selective  Disentangle effects  Paul Broca: “Tan” language impairments  Wernicke’s aphasia: meaning o Split brain research  Callostomy  Wada test o HM – temporal lobe/ hippocampus  Anterograde amnesia  Retrograde amnesia  Working memory o Impaired attention o Approaches to studying the brain  Localisation vs differences in processes  Double dissociation (e.g., vowel and consonants) Transcranial Magnetic Stimulation o Wire on patient’s head o Brief excitability then reduce excitability  disorganise neural activity o High temporal resolution, low spatial resolution o What TMS tells us  Task competition, brain area essential for a task o Sham TMS

7A+B: HORMONES -

Hormones o Protein hormones - social bonding (oxytocin), metabolism (insulin), menstruation (LH), hormone release (gonadotropin-releasing hormone)

o o

Amine hormones - metabolism and bodily functions (adrenaline and melatonin) Steroid hormones - stress (glucocorticoids), sexual reproduction (oestrogen and testosterone) 

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amino acid vs cholesterol, extracellular vs intracellular receptor, secondary messenger vs DNA/ protein production, rapid vs slow, prolonged vs long lasting, number of receptors vs cofactors, vesicles vs cannot be stored

Hormone production o Pituitary (anterior/ posterior) o Endocrine glands  Follicles  Follicular cells  Lumen  Capillaries  Target cells Hormone management o Feedback loops (negative/ positive)

o

Autocrine feedback – acid in stomach  

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Target cell feedback – glucose uptake  

o

o

Hypothalamus, posterior pituitary gland: oxytocin Mammary gland

Bone growth     

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Hypothalamus: thyrotropin-releasing hormone (TRH) Anterior pituitary gland: thyroid stimulating hormone (TSH) Thyroid gland: thyroxine Body basal metabolic rate

Effects of hormone o Milk let-down reflex  

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Hypothalamus Adrenal medulla: adrenaline

Brain and pituitary regulation – temperature    

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Pancreas: insulin Muscle/ fat cells: take up glucose

Brain regulation – fight/flight  

o

Stomach wall cells: prostaglandin Parietal cells in stomach: HCl

Hypothalamus: somatocrinin (RH) Anterior pituitary: growth hormone Sleep, stress, starvation, vigorous exercise Reversal effects: accelerated growth Psychological dwarfism

Hormone and biological rhythms o Pineal gland  Birds and reptiles – directly through skull  Mammals – cervical ganglion  Secretion: Phasic, in bursts  Melatonin  Hamster’s Breeding season  Pineal gland: melatonin, hypothalamus, GnRH, gonadotropin, gonads atrophy/ swells o Eating  Ghrelin o Reproductive behaviour  Oestrous cycle  2 phases: Proestrus (ovulation) + oestrous (receptive period)  GnRH surge, follicle growth, oestrogen increase, egg released, progesterone release, implantation of the egg  Lordosis response, bulling  Beall & Tracy (2013) – wear red Oxytocin o Peptide hormone o Animal evidence  Female rats:  ↑oxytocin receptors… ↑maternal behaviours  blocking receptors… ↓maternal behaviours  Prairie voles:  oxytocin injections… ↓aggressive

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 oxytocin antagonist… ↓caring behaviours towards pups  Madden & Sutton-Brock (2010): meerkats  Oxytocin injections… ↑prosocial behaviours (guarding, pup feeding, closeness to pups, communal digging) + ↓initiation of aggression o Humans  Kosfield et al, 2005 (Oxytocin nasal spray)  ↑ money transfers (= trust and prosociality)  Zack et al., 2007  ↑ likely to donate  Marsh et al., 2010  ↑ Rated face as happy  Plasma oxytocin increases during orgasms, reduce anxiety Endocrine vs Nervous system o Chemical vs electrical impulses o Bloodstream vs nerve circuits o Entire body vs direct connection o Graded signal vs all or nothing o Longer lasting vs fast effect o No vs some voluntary control

8A+B: GENETICS -

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Genetics o Genes o DNA o Histone o Chromosomes o Nucleus o Transcription, alternative splicing, translation o Gene expression o Genome – full set of genes in an organism/ species o Protein synthesis o Allele o Dominant vs recessive o Homozygous vs heterozygous o Polygenic inheritance o Genotype o Phenotype o Punnett square Gene and Behaviour o Gene expression’s influence o Heritability o Phenotypic variance, genetic variance, environmental variance o VT = VG + VE o H2 = VG/ VT o Response to selection: R = h2 x S

Selective breeding  Nest building of mice  Maze-running in rats (strong environmental impact) Mutations o Harmful or neutral o Gametes vs somatic mutation o Wild-type allele vs mutant allele o Monomorphic vs polymorphic o Mutagens o Knockout  Social amnesia in male mice (knock out oxytocin gene) Twin and adoption studies o MZ identical twins’ adoption o Hyperactivity, autism, major depression, schizophrenia o Problems  Heritability not comparable across environments  Biased sampling – income  Not clearly separate genetic and environmental factors Human subjects in research o Ethical guidelines and consent o Categorise: biologically vs non-biologically determined traits Sex and gender o Mutations o Triple X syndrome o Klinefelter syndrome (XXY) o Missing chromosome o Intersex: sexual organs anomalies o Individual ...