Lectures For Test 2 Flashcards
Neural networks
Complex organizations of neurons that 1. Receive information and interpret and 2. Produce and output response from network Itself.
- can adapt and change
- more connections between neural network than neurons itself
Glial cells
Doesn’t transit or receive information but is a neuron.
- dispose cellular waste
- insulate the axons to increase speed
- form blood/brain barrier
- form white matter of brain
Dendrites receive
- Excitatory messages- neuron should fire action potential
2. Inhibitory messages- neuron should not fire action potential.
Cell body (Soma)
When will neuron fire
Integrates all excitatory/ inhibitory information
-if the difference in excitatory and inhibitory messages reach a threshold, neuron will fire
Axon states
- Resting potential
- neuron has stored up electrical chemical energy (polarized)
- has capacity to create an action potential. -70 millivolts - Action potential
-release of the stored up electrical energy (depolarization)
-neuron fires
+40 millivolts - Refractory period (reset chemical polarization
- absolute (not possible for axon to fire action potential)
- relative (possible to fire again, but cel body needs to exceed threshold by greater amount)
All or none law
Size of action potential is not influenced by increases in intensity of stimulation beyond the threshold. Ap only travels away from the cell body down to axon.
More frequent fires=
Greater i transit of stimulation
Biochemical basis of AP
Outside membrane is positively charged, inside is negatively charged. Positive floods in during AP. During refractory period, sodium pump removes sodium back to outside.
Nodes of ranvier
Gaps in muskets sheath what allow electrical impulses to jump to speed up transmission
Myelin sheath related diseases
MULTIPLE SCLEROSIS- hardening if fatty tissues in neurons
Gillian-Barńe syndrome- disruption in immune system where myelin sheath is seen as a pathogen
Alzeihmers?
Synapse
Electrical impulses (action potentials) travel from one neuron to another across a tiny junction known as a synapse
Reuptake
Neurotransmitters in the synapse are reabsorbed into the sending neuron through the process of reuptake.
Ex: cocaine blocks reuptake of dopamine= more euphoria
If not reuptaken, what happens to neurotransmitters
Special enzymes in the synapse destroy them into basic waste
Neurotransmitters
Have specific effects on behaviour, and operate in specific neural pathways
Neurotransmitters to note
- Acetylcholine (ACH): enables muscle action, leaning and memory (under supply=Alzheimer’s
- dopamine: affect movement, learning, attention and emotion
- serotonin: affects mood, hunger, sleep and arousal (under supply= depression)
- norepinephrine: helps control alertness and arousal
- GABA: inhibits it neurotransmitter
- Glutamate- excitatory neurotransmitter involved in memory
- endorphins: natural pain killers
Key lock analogy
Neurotransmitter molecule ha a molecular structure that precisely fits the receptor site on the receiving neuron, much as a key fits a lock
Agonists
Antagonists
Similar enough in its structure to be neurotransmitter molecule that it mimics its effects on the receiving neuron. Morphine mimics endorphins
Inhibits! Structure similar enough to the neurotransmitter to occupy its receptor site and blocks its action, but not similar enough to produce effect.
Brian’s structures
Forebrain= cerebral cortex and limbric system= thalamus, hypothalamus, hippocampus and amygdala
Midbrain- reticular formation
Hindbrain= cerebellum, medulla and pons
Oldest part of the brain
Hindbrain, automatic functions
Fissures
Gyri
Creases in brain (central and lateral)
Hills that lies between segmentation of brain. Higher areas between fissures.
Frontal lobe
- executive functioning: ability to plan, make decisions, judgments, and inhibit inappropriate behaviour (GABA)
- important in working memory
- language Center (brocade area): expressive language
- primary motor cortex: voluntary motor movements
Alcohol works as a ___ antagonist
GABA
GABA inhibits inappropriate behaviour so alcohol causes it
Temporal lobe
- sound
- primary auditory area: ability to process sounds/speech
- wernicks area: receptive language (collect/understand language)
Parietal lobe
- Integrating sensory information
- somatosensory area (body sense): ability to sense anything in skin and collect information from sense organs
Occipital lobe
- vision
- primary visual area
- optic nerve terminates in here
Functions of the cortex
Output: motor cortex (left hemisphere section controls right side of body)
Input: sensory cortex (left hemisphere section receives input from the body’s right side)
Contra lateral organization
The Bain has two hemispheres. The left hemisphere controls/ senses the right side, and the right side controls/ senses the left side
There is more sensory cortex slighted to the _____ than the _____, but overall the _____ have the most brain tissue slighted to them
Lips
Back of the knees
Hands
Language steps
- Visual cortex- receivers written words as visual stimulation
- Angular gyrus- transforms visual representations into an auditory code
- Wernickes area- interpreted auditory code (temporal lobe)
- Broca’s area: controls speech muscles via the motor cortex (translating into speech muscles)
- Motor cortex: word is pronounced
If you can speak but not read you have damage to your
Wernicks area
Language centres tends to be in the ___ hemisphere in ____ handed people
Left
Right
Right hemisphere in right handed people is specialized in _____ processing/ ______
Spatial
Depth perception
Corpus callosum
- allows left/ right hemispheres to communicate
- is white in colour meaning there are axons
Split brains
- usually for people with extreme epilepsy
- attempt to isolate seizures in 1 hemisphere only
- individuals are remarkably normal after surgery
Split brain experiment with form and spoon
Screen with fork on right side and spook on left. When asked what they see, fork is proceeded in left hemisphere and person says fork. Right hemisphere sees left side of screen but cannot verbalized this. But can pick up the correct object using left hand.
- right hemisphere does spatial processing
- left hemisphere does language
Optic chiasm
Crossover pint of axons in optic nerve
Both eyes pick up both visual fields, but the ______ sorts out which hemisphere processes this
Optic chiasm
Split brain experiment with blocks
Person asks to reproduce block diagram. If the pattern is given to left hemisphere, the right hand cannot recreate it. If given to right hemisphere, the left hand can reproduce it. When frustrated the left hand would jump in to help.
Split brain interpreter experiment
- Split brain watches as different images flash simultaneously on the left and right.
- Below the screen is a row of other images.
- Asked to point each hand at a bottom image that relates most to the image flashed ins green on that side of the screen.
- Left hemisphere points the right hand at a picture of a chicken. The left hemisphere says that the chicken claw goes with the chicken head.
- Right hemisphere points the left hand at a picture of a shovel. The left hemisphere decided that the shovel is used to clean up after the chickens (it does not see the snow house).
- left hemisphere interprets
Rearwards for making correct predictions experiment
Radom sequence of lights where 70% is red and 30% is green. Animals hit red always so they would get treats 70% of the time. Humans noticed strategy and hit red 70% of time and green 30% of time but then won 58% only. Split brain people when task presented to left hemisphere performed like humans and like animals when in right hemisphere.
Sodium amobarbital
Puts one brain side to sleep
- speech localization
- used before surgery to see what functions will be altered if a mistake is made.
Is the left side more logical and right more artsy?
No false
Thalamus
-processing/ distributing sensory information and directing information to parts of the brain. (Except smell-has direct connection)
Hypothalamus
- homeostasis: earring, drinking, body temp
- controls emotions
- levels of arousal
- regulates sexual activity
- critical part to connect endocrine system and nervous system (transforms electrical messages to chemical hormonal messages)
- contains reward centres
- is not a gland
Reward center
Pleasure Center to motivate behaviour
Ex: rats will cross an electrified grid for self stimulation of pleasure Center when electrodes are placed in the reward Center
If you stimulate a violent person’s hypothalamus it
Calms them down
Hippocampus
- invoked in memory functions (consolidation of long term memories, from short term memories)
- remembered objects/spaces (spatial memory)
- taxi drivers have large hippocampuses
Amygdala
- primary threat detector
- modulates fear/ aggression
- regulates attentions
Reticular formation
- Connecting structure from spinal cord and cerebral cortex
- crossover point of directing nerve drivers from one side of the body to other side of brain.
- parts involved in stages of sleep
- arousing function and consciousness
Cerebellum
- Balance, coordination, posture, fine motor movement
- me with storage and learning
Pons
- connects cerebellum and parts of hindbrain to cerebral cortex
- regulates conscious experience like sleep/wake cycles
- brings on initial state of falling asleep
- facial movement functions
- balance, muscle coordination and posture
Medulla
- regulates automatic processes
- breathing, heartbeat, blood pressure and digestion
- sneezing and swallowing reflex
Overview of functions of hindbrain, limbic system and cortex
Hindbrain- automatic processes, heart rate, breathing and digestion
Limbic-motivation, emotion and memory
Cortex- surface layer that integrates sensory information, coordinates movement and thinks and reasons
rTMS
Repetitive transcranial magnetic stimulation
Magnet helmet that strategically disrupts cerebral cortex parts by magnets.
EEG
Electroencephalogram
- cap of electrodes that connect to computer to measure brain activity
- help tell us when the brain respond to a stimulus
PET
Radioactive glucose tracers in the brain to see what parts of the brain are using more energy
MRI
fMRI
Static pictures of Brian structures
Measures brain activity by where the blood flow is while doing a task
Endocrine system parts and functions
Hypothalamus- controls pituitary (not a part)
- pituitary: master gland that secreted hormones
- parathyroids: regulate level of calcium in blood
- adrenal gland: trigger flight of fight
- pancreas: blood sugar level
- testis/ ovaries: male/ female sex hormones
- thyroid: affects metabolism
Nature vs nurture debate
Biological heritage (Plato) vs environmental influences (Aristotle)
Gene environment interactions
We are the product of interactions between our genetic predispositions and our surrounding environments. Neither nature/ nurture is more important.
How is children’s temperament depended on genes and environment
East going baby attracts caring environments which create a happier and friendlier child and adult
Darwin finches
Environment caused the same species to change gene expression and change appearance to suit their needs
Siamese cats
Marking determined by gene depending on temperature. Kittens are pure white but cooler parts of body which have less blood flow and therefore less enzyme gets darker colours.
Diet and phenylketonuria
Recessive disorder leading to lower IQ scores. With appropriate diet (environment), possible to eliminate/ reduce brain damage.
Hypothesis: children love in MAI are more susceptible to effects of maltreatment.
Results:
- high MAO + lower maltreatment= less likely to commit violence
- low MAO + no maltreatment= lowliest crimes (environment)
- low MAO+ severe maltreatment = more likely to commit violent offence
Behaviour genetics
Study of our differences and weights the relative effects of heredity and environment.
Evolutionary psychology
Studies the evolution of behaviour and mind using principles of natural selection.
Nucleus
Chromosome
Inner area of cell that houses chromosomes and genes
Threadlike structure made largely of DNA molecules
How many chromosomes do humans have
23 pairs. 23 from mom, 23 form dad
Why is there 70 trillion ways to make a human
2 chromosomes to choice from each parent = 4 different ways chromosomes pairs can be paired
Chromosome 21 and 23
Lack of causes Down syndrome
Gender chromosome
Genome
A set of complete instructions for making an organism, containing all the genes in the organism.
Humans have 20000-30000 genes in genome
Alleles and types
Variation on a gene
Dominant- expressed when present
Recessive- expressed only when gene is matched form other parent
Heredity
Passing on traits by reproduction
Genotype
Phenotype
Actual genetic makeup
Observable characteristics (results from both genetic and environmental influences)
Polygenetic effects
More than one gene contributed to an expressed characteristic
Identical twins more likely to be similar in these ways regardless of being raised together or not
- physical ways
- mental abilities
- extroversion, agreeableness, conscientiousness
- psychiatric illness
Who are adopted children more similar to- biological or adopted parents?
Biological parents
Only more similar to adopted parents in religion, political views and mannerisms
Temperament
A persons stable emotional reactivity and intensity
Strong genetic component but environment works too.
Heritability
The extent to which the differences amok by people attribute to genes
-applies to differences in populations only
IQ and heritability
At age 5- 22% heritable
At age 75+-62% heritable
Children have broader ranges in environment than 75 year olds
Male and female coat of reproduction
Men: low costs, mating with multiple females
Women: high cost, select one caring male to help raise children
Men and women important traits rankings
Kindness and intelligence rated first and second for both. Beauty was ranked higher for men, and good earning was higher for women.
Darwinian grandparenting
Grandparents invest most in grandchildren that are more similar to their genes
Maternal grandma = 1
Maternal grandpa = 2
Paternal grandma = 3
Paternal grandpa = 4
As you get older many sensory systems work at
20-35%
Limited receptivity
Pilfer out and select information to pay attention to
Contrast
How we detect something is getting more intense
Sensation
Perception
Sense organs detecting psychical energy (stimulus) in the environment and converting it into neural signals.
The brains selecting, organizing and interpreting of sensations
Distal, proximal and precept
Distal stimulus (book) -physical stimulus from sense organs
Proximal stimulus (retinal image of book) -representation of distal stimulus
Percept(recognition of object as a book)
-integration of sensory information and the meaning of the distal stimulus
Illusions or impossible figures work by
Breaking rules by drawing 3D shapes in a 2D space
Have same stimulus but different perceptions
Can you see both of the images in a reversible image at the same time?
No, you switch back really quickly from which image is the figure and other the ground.
The size of a retinal image tells us about its
Distance
Subliminal threshold
Stimulus intensity below absolute threshold that we are unconscious and unaware of
Worthingtons light contrast experiment
Participants presented with 2 stimulus es of light of equal intensity. Before the light participants are subliminally presented with either a neutral word or taboo word in front of each light. Light processed with taboo word always perceived as more dim.
Lexical decision task
People give. Long list of stimuli with non words and real words. People decide if each is a word or not. Measure how quickly a person can detect words. Within list, certain words are prime targets (words Pairs that relate or don’t relate). Target pairs that are related caused target to be reacted to quicker if related to prime. (Priming)
Marcels priming experiment
Used lexical task but found when subliminal prime word was given, it caused a quicker reaction time to a target word even when person was unaware of it.
Does subliminal persuasion work?
No
Subliminal perception
Unconsciously seeing (perceiving) things that cause a direct effect on your behaviour.
Nervous system
Endocrine system
Speedy electrochemical communication using nerve cells
Slow hormonal communication system
CNS
PNS
Central nervous system
-brain and spinal cord
Peripheral nervous system
- connects CNS to rest of the body
- connects all sensory systems to the brain and allows brain to message the body.
Nervous system parts
- Peripheral
- -Automatic (self regulating, unconscious functions like heartbeat, sweating, breathing)
- Somatic (controls voluntary movements of skeletal muscles)
- Off of automatic system
- sympathetic (arousing)
- parasympathetic (calming)
Examples of sympathetic and parasympathetic
Sympathetic
- dilated pupils
- accelerates heartbeat
- inhibits digestion
- stimulates glucose release
- relaxes bladder
Parasympathetic
- contracts pupil
- slows heartbeat
- stimulates digestion
- contracts bladder
Can you be in a sympathetic state long
Not Healthy to be
- organs fail
- too many hormones
- can’t be in both at same time
Kinds of neurons
Sensory (afferent)- detects psychical senses and sends to brain
Motor (efferent)- sends message from brain to body part to move or do something
Interneuron(CNS ONLY)- connect systems together and bring info into and out of the brain
Dendrites Cell body Axon Myelin sheath Terminal branches Nodes of ranvier
Receive messages from other cells
Processes and integrates signals received
Passes messages away from cell body to other neurons
Covers axon and speeds up Neural impulses
Form junctions with other cells
Assist in speed by jumping
Do all neruons have myelin sheath?
No, but ones that do go faster
Terminal buttons
Contain neurotransmitters that are released to synaptic gap/ cleft and migrate to dendrites of receiving neuron
Nerves
Bundles of myelinated axons
- made up of neurons axons
- dedicated to specific function
- only in PNS!!!!!!
Spinal cord and reflexes
Finger tips over flame, instantly move back. Skin receptors pick up on heat and send signals into spinal column and spinal cord sends into to inter neurons that connect sensory neurones to motor neurons to move finger away. Other inter neurons sends info to brain and brain registers as pain. The reflex is quicker than the pain
