biopsychology Flashcards
draw the divisions of the nervous system
nervous system
-CNS (spinal cord and brain). - peripheral nervous system
-somatic NS. -autonomic NS
-sympathetic NS. parasympathetic NS
functions of brain lobes
-frontal lobe = thoughts and production of speech
-occipital lobe = processing of visual images
-parietal lobe processing sensory info
-temporal lobe - hearing
what does the peripheral nervous system do
made up of neurons that connect the CNS to the rest of the body
name the 2 divisions of the peripheral NS
- autonomic nervous system
- somatic NS
what is the function of the autonomic NS
- controls unconscious activities eg digestions and has 2 divisions with opposite effects
what is the function of the somatic NS
controls conscious activities eg running playing a video game
name the divisions of the autonomic NS
-sympathetic NS
-parasympathetic
what is the function of the sympathetic NS
-gets the body ready for action in the flight or fight system
whats the function of the parasympathetic NS
calms the body down it the rest and digest system
draw a sensory neuron with labels
page 77 or 50
draw a relay neuron with labels
page 77 or 150
draw and label a motor neuron
page 77 or 150
whats the function of a sensory neuron
-carries information from sensory receptors (eg vision or touch) and organs to the central nervous system (through somatic system). They are found in various locations eg eyes and ears
whats the function of the relay neuron
- only found in the brain and spinal cord (CNS)
-connects nuerons (sensory) to other nuerons (motor) in order to communicate
whats the function of motor neurons
-carries information from CNS to muscles and glands (somatic and autonomic) and form synapses with muscles to control their contractions.
name the order of transmission of information
- stimulus
2.receptors
3.sensory neuron - CNS relay neuron
- motor neuron
- effectors
- response
why are reflexes important
-they are fast automatic responses they bypass the conscious brain meaning these rapid responses avoid injury
draw and label a synaptic transmission
page 151
order of the nuerosynaptic transmission 4 steps
- once action potential has arrived at the terminal button at the end of the axon
- when the electrical signal reaches the end of neurons it causes nuerotransmittors to be released into the synaptic cleft
- they diffuse across to the post synaptic membrane and bind to specific receptors
- when the nuerotransmittor bind to the receptor they might trigger an electrical impulse causing muscle contraction or hormone to be secreted
what are excitatory nuerotransmittors
such as noradrenaline and adrenaline act as the nervous systems on switches and create an excitatory postsynaptic potential at the postsynaptic membrane. They increase the likihood that the nueron is more likely to fire
what are inhibitory neurotransmitters
such as serotonin (linked to mood) and GABA (has a calming effect) are the ‘off switches’ in the nervous system. They calm the cells in the nervous system and create an inhibitory postsynaptic potential at the postsynaptic membrane making it less likely that the nueron will fire
what is summation
the likelihood of a cell firing is determined by net result of EPSP and IPSP. If there are more IPSP’s acting on a cell at a given time then it will not fire, if there are more EPSP’s acting on a cell it will fire.
order for fight or flight
1.person enters a dangerous situation
2. the amygdala is activated which sends a distress signal to the hypothalamus
3. the hypothalamus activates the sympathomedullary pathway running to the adrenal medulla and the sympathetic nervous system
4. the SNS stimulates the adrenal medulla
5. the adrenal medulla secretes hormones eg adrenaline and noradrenaline in the bloodstream
6.adrenaline causes psychological changes to prepare the body for flight or fight
physical effects of fight or flight
-brain racing
-heart racing
-sweating
- shaking trembling
function of areas of the brain
-cerebellum = motor skills eg balance and coordination of muscles
-brain stem = automatic functions eg breathing heartbeat
-cerebrum = largest part of brain split into 2 halves ( cerebral hemispheres)
diencephalon eg hormone
draw and label the adrenal glands
inside- blood vessels, medulla and cortex which releases adrenaline and noradrenaline in flight or fight
outer- cortex produce cortisol increase sugar in bloodstream
draw and label the pituitary gland
- anterior pitutitary gland eg ACTH and corisol
-posterior gland eg oxytocin
evaluate flight or fight
- flight of fight cant explain gender differences in stress reactions eg tyler found that women show a tend( protect their infants) and befriend (form alliances with other women) TMB it suggests that previous reserch mainly focused on men has abscured pattern of stress reactions in females
- fight or flight doesnt always produce negative behaviours eg von dawans found acute stress can bring human connections eg 9/11 TMB humans are social creatures which allow us to survive
-flight or fight not necesarily the first reaction to human threat ed gray suggests we have a freeze responce where we stop look and listen TMB maybe there is more variation into how we respond suggesting complexity in behaviour
what is the endocrine system
a network of glands throughout the body and manifacture and secrete chemical messangers known as hormones using blood vessels to deliever hormones to target sites in the body long lasting effect regulated by feedback
draw the endocrine system
stimulus eg low blood glucose
receptors- on pancreas detect low blood glucose concentration
hormone - the pancreas release glucagon into blood
effectors - target cells in liver detect glucagon and convert glucagon to glucose
response - glucose realeased into blood so glucose conc increases
hypothalamus
connected to the pituitary gland and is responsible for stimulating or controlling the release of hormones from the pituitary gland. Therefore, the hypothalamus is the control system which regulates the endocrine system.
pituitary gland
known as the ‘master gland’ releases hormones to control other glands in endocrine system 2 main parts anterior ANTERIOR produces ACTH which stimulates the adrenal cortex and the release of cortisol during the stress
response. POSTERIOR releases oxytocin Responsible for uterus contractions during childbirth.
adrenal glands
ANTERIOR made up of Adrenal medulla releasing adrenaline & noradrenaline responsible for key hormones in flight to fight response POSTERIOR in the Adrenal cortex produces cortisol during stress reactions
name 2 structural functions of a nueron and how it affects transmission
myelin sheath = an insulating layer around the axon to aid transmission of the electrical impulse
dendrites receive signals from other nuerons or sensory receptors
definition of localisation
the theory that specific areas of the brain are associated with particular physical and psychological functions
Frontal lobe what’s in it
motor cortex- voluntary motor movements
broca’s area - language production posterior portion of frontal lobe or left hemisphere
Temporal lobe what’s in it
Auditory cortex- concerned with hearing on both sides of the brain
Wernicke’s area - speech production posterior portion of left temporal lobe
occipital lobe what’s in it
visual cortex - location for vision
parietal lobe what’s in it
somatosensory cortex - location of processing sensory information eg touch
The motor cortex
Responsible for generation of voluntary motor movements eg playing games. Located in the frontal lobe along the pre central gyrus. Both hemispheres have a motor cortex one side of brain controlling opposite side of the body. they exert control over different parts of the body eg the region that controls the actions of the foot is next to the region that controls the leg and so on.
The somatosensory cortex
detects sensory events arising from different regions of the body. in the parietal lobe in a region known as postcentral gyrus. Using sensory information from the skin the somatosensory cortex produces sensations of touch, pressure, pain and temperature which is localised specific body regions on one side of brain receiving sensory information from opposite side of body
visual centres
The primary visual centre in the brain is located in the visual cortex, in the occipital lobeof the brain. However, visual processing actually begins in the retina, at the back of the eye, where light hits the photoreceptors (rods and cones). Nerve impulses from the retina are thentransmitted to the brain via the optic nerve. but the majority terminate in an area of thebrain called the thalamus, which acts as a relay station, passing this info on to the visual cortex. The visual cortex spans both hemispheres, with the right hemisphere receiving its input from the left-handside of the visual field, while the visual cortex in the left hemisphere receives its input from the right-hand side of the visual field. The visual cortex contains several different areas, with each of these areas processing different types of visual information, such as colour, shape or movement.
auditory centres
concerned with hearing most of this area lies within the temporal lobes on both sides of the brain where we find the auditory cortex auditory pathways begin in the cochlea in the inner ear sound waves are converted into nerve impulses which travel along the auditory nerve to the auditory cortex
language centres
Broca’s area:This area is named after Paul Broca, the F neurosurgeon who treated a patient rereferred to as ‘Tan’ Tan had been able to understand spoken language, he was unable to speak, nor express his thoughts in writing. ,along with lesions in their left frontal hemisphere. Patients with damage in these areas in the righthemisphere did not have the same language problems. This led him to identify the existence of a ‘languagecentre’ in the posterior portion of the frontal lobe of the left hemisphere, Broca 1865. This area is believedto be critical for speech production.
Wernickes area
Shortly after Broca had discovered a ‘speech production’ area in the brain, Carl Wernicke, discovered another area of the brain that was involved in understanding language.This Wernicke’s area, was in the posterior portion of the left temporal lobe. Whereas Broca’spatients could understand language but not speak, patients with a lesion in the Wernicke’s area couldspeak but were unable to understand language. Wernicke proposed that language involves separate motorand sensory regions located in different cortical regions. The motor region, located in Broca’s area, is closeto the area that controls the mouth, tongue and vocal cords. The sensory region, located in Wernicke’sarea, is close to regions of the brain responsible for auditory and visual input. Input from these regions isthought to be transferred to Wernicke’s area where it is recognized as language and associated withmeaning. There is a neural loop running between Broca’s area and Wernicke’s area. At one end lies Broca’sarea, responsible for the production of language, and at the other lies Wernicke’s area, responsible for theprocessing of spoken language
definition of lateralisation
the dominance of one hemisphere of the brain for particular physical and psychological functions
definition of lateralisation
the dominance of one hemisphere of the brain for particular physical and psychological functions
hemispheric lateralisation
each hemisphere has functional specialisations this means that the neural mechanisms underpinning particular functions are localised primarily in one half of the brain
what is found on the left hand side of brain
language areas. speech production and comprehension left hemisphere of frontal and temporal lobe
what is found on the right hand side of brain
primarily linked to visual-motor tasks such as map reading and sports
role of corpus callosum
connects the left and right hemisphere and enables messages to enter the right hemisphere to be conveyed to the left hemisphere and vice versa
what is a treatment for severe epilepsy
cutting the bundle of nerve fibres connecting the two hemispheres
-to prevent extreme electrical activity that accompanies seizures from crossing from one hemisphere to another
split brain research theory
-info from left visual field goes to right hemisphere and into from right visual field goes to left hemisphere
-when corpus callous no way info can travel to the other hemisphere
split brain procedure
-patient asked to focus on a dot in centre of screen
-info present to either right/left visual field
-asked to respond either left hand (controlled by right hemisphere) or verbally (left hemisphere)
what would happen if a picture of a dog was flashed to the right visual field
because it is controlled by left hemisphere it is responsible for language they will say dog
what would happen if a picture flashed to left visual field
because it is controlled by right hemisphere used for visual spatial task they will see nothing
definition of plasticity of the brain
describes the brains tendency to change and adopt functionally and physically as a result of experience and new learning
cognitive pruning
research shown that the brain continues to create new neural pathways and alter existing ones rarely used connections are deleted and frequently used connections are strengthened
functional recovery of the brain
-researchers found stroke victims were able to regain functioning and areas of the brain are able to rewire as other parts of brain take over functions of the damaged area
neuronal unmasking
some synaptic and neural connections are dormant because they rarely have neural input or activated too infrequently
-when damaged the dormant synapses can be opened
stem cells
are unspecialised and can develop into different types of cells with different functions
-if damaged stem cells can replace dead/ dying cells OR could release a growth hormone to ‘rescue’ injured cells transported cells more provide a network of nuerons to connect to injured part
fMRI
uses large magnets to detect measures oxygenated haemoglobin blood flow
-more active areas receive more oxygenated blood which indicates specific structures are working hard at that point
evaluation of fMRI
+good spatial resolution of 1 mm to precisely identify active brain regions eg role of dopamine in addiction
+non-invasive good ethical validity
-5 second delay important info not detected
EEG
-electrocephalogram
-measures electrical activity in the brain via electrodes placed on the scalp
-show brainwave
-epilepsy shows spikes of electrical activity
-alzheimer patents show slowing of electrical activity
different wave lengths and their role
Alpha, beta, delta and theta
-awake but relaxed = alpha
-physiological aroused =beta
-REM sleep =beta
-sleep = theta
-light to deep sleep =delta
ERP
-event related potentials
-small voltage changes triggered by specific stimuli or cognitive events (picture or sound)
where are circadian rhythms found
-synchronised by master endogenous pacemaker called the superchiasmatic nucleus found in the hypothalamus
sleep wake cycle
sleep-wake cycle regulated by external homeostasis signals such as light it had dips and rises
-biggest sleep drives between 2-4am and 1-3pm
-after a lot time being awake we use large energy therefore homeostatic drives peak during late evening to recharge
core body temperature
best indicator of circadian rhythm
-lowest (36 degrees) = 4:30am
-highest 38 = 6pm
-small dip between 2-4pm explaining afternoon drowsiness
-hormones such as melatonin by pineal gland peak during hours of darkness promoting sleep
ultradian rhythms
-cycles lasting less than 24 hours such as sleep stages involving a repeating cycle of 90-100 minutes with 5 stages
sleep stage 1
-4-5%
-light sleep
-muscle activity and muscles may twitch
-theta waves
sleep stage 2
-44-55%
-breathing and heart rate slows
-slight decrease in temperature
-theta waves
sleep stage 3
-4-6%
-deep sleep begins
-delta waves
sleep stage 4
-12-15%
-very deep sleep
-rhythmic breathing limited muscle movement
-delta waves
sleep stage 5
-20-25%
-REM
-brainwaves speed up and dreaming occurs
-muscles relax and heart rate increases
-breathing is rapid and slow
-alpha/beta waves
who developed BRAC cycle
kleitman
BRAC best rest activity cycle
-90 minute rhythm during day time moving from alertness to physiological fatigue.
-human mind can focus for a period of about 90 minutes
-then the body runs out of resources
-resulting in loss of concentration, fatigue and hunger
what is a infradian rhythm
-cycle with a duration longer than 24 hours such as female menstrual cycle regulated by hormones
menstrual cycle
between 23 to 36 days average is 28
-regulated by hormones released by the pituitary gland either promoting ovulation or perpare uterus for ovulation
-oestrogen levels peak lasting 16-32 hrs
-after ovulation progesterone increases to prepare possible implantation of an embryo
SAD seasonal affective disorder
-annual rhythms related to seasons in particular migration in response to lower body temperatures
-seasnoal variations affect mood particularly in women
-can become severely depressed in winter months
explanation for SAD
melatonin is secreted for a longer period of time due to lack of light
-therefore is thought to have an affect on the neurotransmitter serotonin creating depressive symptoms
definition of endogenous pacemakers
internal body clocks eg suprachiasmatic nucleus lies in hypothalamus
definition of exogenous zeitgebers
reset biological clock every day to maintain its coordination with external world eg social cues such as light
suprachiamatic nucleus
Tony cluster of nerve cells in hypothalamus
-acts as ‘master clock’ in regulating body circadian rhythm
-nuerons in SCN synchronise so their target cells receive time coordinated signals
-SCN resets itself by light receive info about light from optic nerve
pineal gland
-send signals from SCN to increase melatonin at night and to decrease it as light levels increase
-melatonin promotes sleep by inhibiting responses in brain related to wakefulness
-sensitiveity of SCN and pineal gland must be synchronised with light-dark rhythms
light
receptors in SCN are sensitive to light changes use this info to synchronise activity of organs and glands within the body
-light resets body clock
-photoreceptors detect brightness
-protein melanopsin sensitive to light
social cues
eg mealtimes and social activities
-research has shown people recover from jet lag more quickly if they go outside more in new time zone
