biopsych Flashcards
the nervous system?
NS= breaks into CNS and peripheral NS then peripheral - somatic and autonomic= then autonomic to sympathetic and parasympathetic and somatic- sensory NS and motor NS
what is the central ns?
brain and the spinal cord and it controls behaviour and regulates physiological processes.
What’s the spinal cord and function?
Relay message between brain and body allows brain to regulate breathing digestion- also allow reflexes.
What 4 regions is the brain split into?
Cerebrum, cerebellum, diencephalon, brain stem.
Cerebrum?
Largest brain section and divided into 4 lobes.
What holds the cerebrum together?
Corpus callosum
Cerebellum? What controls where is it?
Back of brain, involved in motor skills balance coordination.
Diencephalon? Where and what?
On top of brain stem, holds thalamus and hypothalamus.
What is the thalamus?
Acts as a relay station for nerve impulses coming from senses and routes them to the appropriate part of the brain to be processed.
What is the hypothalamus?
Number of important functions including the regulation of body temperature hunger thirst, keeps body in homostatis.
Acts as link between endocrine and NS and release of hormones from pituitary gland.
Brain stem ?
Regulates automatic functions, heartbeat, breathing etc.
What is somatic NS?
Controls muscle movement and receives info from sensory receptors
What does the autonomic NS do?
Transmits info to and from internal bodily organs- works automatically such as breathing HR.
What is the autonomic split into?
Sympathetic and parasympathetic
What does the sympathetic NS control?
Helps start our fight or flight- uses noradrenaline to increase HR and blood pressure.
What does the parasympathetic do?
Restores the body to an equilibrium
Similarities between brain and spinal cord?
Both control involuntary processes
Differences between brain and spinal cord?
Provides conscious awareness and allows for higher order thinking while spinal cord allows simple reflex responses.
Main consists of multiple regions responsible for diff functions whereas the spinal cord has one main function
Similarities between somatic and autonomic?
Sympathetic and somatic response to external stimuli
Sympathetic NS responds by preparing body for fight or flight and somatic NS responds to external stimuli by carrying info from sensory receptors to spinal cord and brain
Differences between somatic and autonomic?
-Autonomic consists of two sub components whereas somatic has one.
-Somatic has sensory and motor pathways whereas autonomic only has motor.
-Autonomic controls internal organs and glands and somatic controls muscles and movement.
Neuron structure?
-consists of cell body and includes a nucleus.
-dendrites expand out and carry nerve impulses out
-axon carries impulses away from cell body
-axon is covered in myelin sheath
what is a sensory neuron?
-carry nerve impulses from sensory receptors and convert it into neural impulses and when they reach the brain they are translated into sensations.
-some sensory neurons terminate in the spinal cord to allow reflexes.
what is a relay neuron?
-allow sensory and motor neurones to communicate with each other and connect neurons together located in the spinal cord and brain and are common.
what is a Motor neuron?
-refers to neurons which begin in CNS but project their axons outside the CNS and directly or indirectly control muscles or glands
-when stimulated motor neurons release neurotransmitters which bind to receptors on the muscle and trigger a response leading to muscle movement.
what is a synapse?
Small pocket of space between two cells where they pass messages across
what is the endocrine system?
-network of glands throughout the body which make and secrete hormones.
what is the pituitary gland?
-master gland and it controls the release of hormones from each gland in the system.
what is the hypothalamus?
-stimulates and controls the release of hormones from the pituitary gland.
what is the posterior pituitary? +Anterior?
-Anterior Adrenocorticaltrophic - stimulates the adrenal cortex and release of cortisol during stress response
-posterior oxytocin-responsible for uterus contractions.
what is the pineal gland?
melatonin- responsible for bio rhythms
what is the thyroid gland?
thyroxine- metabolism
what is the adrenal gland?
adrenal medulla- adrenaline and noradrenaline- fight or flight.
adrenal cortex- cortisol- glucose to provide energy while suppressing immune system.
what are the ovaries and testes?
oestrogen- reproductive system
testosterone-male sex charcteristics
two main pathways for fight or flight?
- sympathetic- adrenal medullary system and hypothalamic pituitary adrenocortical
what is the sympathomedullary pathway?
-in charge of immediate stress response and sends signals to the SNS which activates the adrenal medulla which releases adrenaline then the parasympathetic branch restores the body.
what is the HPA system?
-body’s response to chronic stress- hypothalamus sends signals by CRH to pituitary when the pituitary is activated it produces ACTH which activates adrenal cortex which releases cortisol.
What is localisation of the brain?
Principle that specific functions have precise location in the brain
What is the motor cortex?
Responsible for voluntary motor movements- located in frontal lobe with both hemispheres having one and it controlling the opposite side of the body.
what is the somatosensory cortex?
receives sensory input from receptors in the skin eg touch, pain, pressure etc, in both hemispheres.
what is the visual cortex?
receives input directly from eyes and auditory ears, both hemispheres.
what is the brocas area?
speech production, damage to this area typically means you produce little speech, located in frontal lobe and discovered by paul broca.
what is wernicke’s area?
comprehension of speech, damage usually means poor speech comprehension found by carl wernicke and located in the temporal lobe.
what is hemispheric lateralisation?
difference between functions of different sides of brain eg ability to produce and understand language is produced in the left hemisphere and right is visual motor tasks.
what was sperrys study? and what did it prove
-1968 individuals who had a commissurotomy.
- word or image could be projected to patients right field or left
- could see when in right field but not with left due to lack of language centres in right hemisphere.
what is brain plasticity?
changes in structure and function of the brain that affect behaviour and that are related to experience of training.
what is the evidence of brain plasticity?
Maguire 2009 conducted research on london taxi drivers who have knowledge of 25,000 streets- aim of the study was to investigate the function of the hippocampus in spatial memory and compared the MRI scans of 50 men who didnt drive taxis- main findings show that the taxi drivers had hippocampi which were significantly largely.
what is neural plasticity?
where different areas of the brain take over functions of areas of the brain which cant function properly.
what structural changes does neural plasticity change?
axonal sprouting- growth of new nerve endings which connect with other undamaged nerve cells to form neuronal pathways.
reformation of blood cells.
recruitment of homologous areas on the opposite side of the brain to perform specific tasks.
evaluation of brain plasticity?
-research to support kuhn et al found higher grey matter in diff areas of the brain after they played vid games for 30 mins over a two month period and proved how experience can cause structural changes in the brain.
what is FMRI? and how does it measure function in the brain?
-involves use of MRI scanner using a large magnet surrounding the participant then interpreted by a computer and into precise three dimensional picture.
-measures function by assessing brain areas with a high count of oxygenated red blood cells which suggest activity.
what is the electroencephalogram?
based on recordings of electrical brain activity by electrodes over a period of time- good temporal resolution and spatial resolution bc its distance from the brain.
what are event-related potentials?
Event-Related Potentials (ERP) use electrodes that are attached to the scalp, as with EEG. However, the key difference is that a stimulus is presented to a participant (for example a picture/sound) and the researcher looks for activity related to that stimulus.
what are post-mortem exams?
analysis of a persons brain following their death.
what is a circadian rhythm?
biological rhythm which happens once in a 24 hour period e.g sleep wake cycle.
what is a infradian rhythm?
happen every month or once a year or so e.g SAD or menstrual
what are ultradian rhythm?
happen more than once in any 24 hour period for example diff stages of sleep.
examples of circadian rhythms?
-temp, dips at 4:30 at 36 and highest at 6pm at 38.
-sleep wake cycle.
example of circadian rhythms being altered?
1972- michel siffre spent 6 months in an underground cave, no natural light and no other external cues as to what time of day it was, monitored patterns of sleeping and waking by sending messages rhythms were 24 hours and sometimes was 48 hours.
examples of infradian rhythms?
-menstrual cycle controlled by the pituitary gland
what controls the menstrual cycle?+example
endogenous factors, progesterone and oestrogen.
-research that shown otherwise russell 1980 made women pair up and rub sweat on each other and cycles became synched due to the pheromones in the sweat.
yang and schank- looked at menstrual cycle in 186 chinese women living in uni accommodation over a year and found no evidence women synch
evaluation of infradian rhythms
good practical application led to effective treatments such as phototherapy murphy 1995 found phototherapy suppressed the secretion of melatonin
how many sleep cycles do you go through a night?
5
different waves of the stages of sleep?
At -alpha
The- theta
table-theta
kids- k complexes and spindles
dont- delta
talk-theta
back- beta REM
what happens during stage 1 of sleep?
- HR slows, decrease body temp and might experience hallucinations.
- alpha waves are displayed on EEG
what happens during stage 2 of sleep?
- EEG pattern synchs with larger slow theta waves with sudden bursts of spiking spindles.
what happens during stage 3 of sleep?
-HR continues to fall, body temp.
-delta waves dominate EEG and less spindles.
what happens during stage 4 of sleep?
-deep sleep hard to wake.
-delta waves.
-growth hormone released
what happens during stage 5 of sleep?
REM.
- body is paralysed but brain suddenly bursts to life
- EEG similar to if awake
-dreams.
who studied dreams and REM?
kleitman 1957- able to show with EEG that dreams mainly occur at stage 5, used electrodes to measure eye movement and scalp.
-theyd be woken and had to say if they’d been dreaming and what about.
-found that all displayed REM between 3 and 50 mins and most dreams reported during REM
what are endogenous pacemakers?
internal factors which control circadian rhythms. e.g SCN and pineal gland.
what are exogenous zeitgebers?
external factors which control circadian rhythms.
what is the suprachiasmatic nucleus? scn
tiny cluster of cells behind the eyes which detects changes in light levels and sends signals to diff parts of the brain. sends signals to pineal gland which begins producing melatonin.
research on superchiasmatic nucleus?
Morgan 1995- bred mutant hamsters by manipulating SCN so 20 hours not 24 the SCN was then transplanted into normal hamsters and they changed to 20 hours shows that the scn plays a key role in controlling rhythms
what are the two main exogenous zeitgebers
light and social cues
research for zeitgebers
- changes in light throughout the body not just SCN campbell and murphy change person’s circadian rhythms by shining lights on the backs of knees and measured melatonin before and after.
-miles 1977 studied a blind man and had a circadian rhythm of 24.9 hours and social cues braille clock did not help train his body clock.
what does the peripheral NS do?
-job is to relay messages from the CNS to the rest of the body.
what does the somatic NS do?
-role is to carry sensory info from outside world to the brain and respond by motor pathways.
what is the somatic NS made up of?
-sensory receptors and motor pathways.
what is the process of synaptic transmission?
Synaptic transmission is the process by which a nerve impulse passes across the synaptic gap from pre-synaptic neuron to a post-synaptic neuron.
* When an action potential reaches the synaptic vesicle of the pre-synaptic neurone, it causes them to release a neurotransmitter through a process called exocytosis.
* The neurotransmitters diffuse across the gap between the pre- and post-synaptic neurones and bind
to specialised receptors on the surface of the post-synaptic neurone.
explain the difference between interactional synchrony and reciprocity?
-interactional synchrony is when two people mirror what the other person is doing in their facial expressions and body movements which includes imitating emotions, for example if a mother smiles a baby smiles too.
-reciprocity is when the mother and infant take turns to respond to each other for example if the mother tickled the infant, the infant would laugh in response.
