Biological Psychology Flashcards
What are motor neurons?
Passes information from the brain to parts of the body (e.g. muscles)
What are sensory neurons?
They are activated by sensory input and send signals to the brain.
What are resting ion channels?
They are always open
What are voltage gated ion channels?
They’re activated by changes in the membrane potential near the channel
What are ligand gated ion channels?
Open to let certain ions in after bonding with a chemical messenger, e.g. a neurotransmitter.
What are mechanically gated ion channels?
They open because of physical distortion to the cell membrane (e.g. touch).
What’s the name for negatively charged ions?
Anions
What’s the symbol for every organelle in the cell that can’t move?
A-
What’s the equilibrium potential of K+?
-90mv
What’s is the sodium potassium pump?
3 sodium(NA+) ions out of the cell and 2 potassium(K+ ions) into the cell
What is the resting membrane potential?
Approximately-65/-70mv
What is the amount of action potential needed for the signal to be passed to another neuron (sodium channel threshold)?
A net change of +15mv is needed to get cell to 50mv
What are the 3 stages of action potential?
Depolarisation,
Repolarisation (& hyperpolarization)
Refractory period
Where is myelin produced?
Glial cells - known as oligodendrocytes or Schwann cells.
When can a second action potential occur?
Once the preceding potential has finished.
What denotes the strength of a stimulus (in terms of action potential)?
An increased firing rate.
What is the name of the gap in the synapse?
The synaptic cleft.
What is ACh?
A chemical messenger to propagate nerve impulses across neuromuscular junctions.
What is calcium’s role in neuronal communication?
Ca2+ binds with synaptic vesicles and causes them to release neurotransmitters.
What are ionotropic neurotransmitter receptors?
One part binds to the neurotransmitter and the other part is an ion channel (lignant gated)
They are on dendrites.
What are metabotropic neurotransmitter receptors?
Indirectly influence ion channels. When they bind with a neurotransmitter, a subunit detaches and opens the ion channel
They take longer to generate the signal but allow more sensitivity & the response outlasts the stimulus.
Type I synapses
Release excitatory neurotransmitters & leads to an influx of positive ions (Na+).
Type 2 synapses
Release inhibitory neurotransmitters that lead to an influx of negative ions (Cl-).
How is postsynaptic potential integrated?
Spatially and temporally
What is glutamate?
Brain’s major excitatory neurotransmitter. Vital in forming links between neurons that are the basis of learning & memory
What is GABA?
the brain’s main inhibitory neurotransmitter
What is dopamine?
a neurotransmitter involved in movement control & reward circuits
What is serotonin
a neurotransmitter that has a profound effect on mood & anxiety
what is acetylcholine?
the neurotransmitter used at the neuro-muscular junction.
What causes Parkinson’s disease?
a loss of dopaminergic neurons in the brain stem (causing rigidity & trembling movements)
What’s a treatment for Parkinson’s disease?
the drug levo-dopa mimics the action of dopamine (an agonist) & temporarily relieves the symptoms.
what’s an agonist?
binds to a receptor and activates the receptor to produce a biological response (works in the same way as a neurotransmitter would)
what can toxins do?
poison ion channels, affect transmitter release or block neurotransmitter receptors
What’s the effect of psychoactive drugs?
mimic the effect of neurotransmitters, or affect the uptake of neurotransmitters. There is an association between drug-taking & reward circuits (releasing dopamine). this could explain addiction
What are the parts of the central nervous system?
the brain & the spinal cord
What are the parts of the peripheral nervous system?
Somatic nervous system & autonomic nervous system (has a sympathetic & parasympathetic division)
gyri
‘hill tops’ on the brain surface
sulci
‘valleys’ on the brain surface
cerebrospinal fluid
the cushion between the skull & the brain
lateral sulcus
separates the 2 hemispheres
central sulcus
separates the frontal & parietal lobe
what is the cerebral cortex?
a layer of nerve cells that covers the outer layer of the brain. the number & variety of neurons varies in different parts of the cortex
what is the occipital lobe’s role?
visual processing
What is the parietal lobe’s role?
touch, balance, & movement
What is the temporal lobe’s role?
hearing, speech, comprehension, memory, & visual recognition
What is the frontal lobe’s role?
movement, thinking, & planning
What is the basal ganglia?
part of the brain in cerebral hemispheres. it’s involved in the control of voluntary movement.
What is the limbic system?
part of the brain involved in our navigation in space, memory formation, & emotional processing.
What is the brainstem?
controls the brain’s general level of alertness & regulate processes (e.g. breathing, heartbeat, & blood pressure). It evolved more than 500 million years ago.
What are the areas of the brainstem?
Hindbrain (including cerebellum), midbrain, diencephalon (including hypothalamus & pituitary)
What are the cranial nerves?
allow the brain to communicate with the muscle & sense organs of the head & neck.
What are the main cranial nerves?
Olfactory (smell), Optic (vision), Trigeminal (mastricatory movements & facial sensation), glossopharyngeal (tongue, pharynx movement, & sensation), & vagus (heart, blood vessels, & viscera movement of larynx/pharynx)
How is sensory information about touch/pain relayed to the brain?
via the spinal cord. the brain sends motor commands back via the spinal cord to the muscles to produce movement
in the sympathetic division of the ANS, what is released when a threat is seen?
ACh (pre-ganglion) & noradrenaline (post-ganglion)
In the parasympathetic division of the ANS, what is released when a threat has passed?
ACh pre & post ganglion
anterior meaning
located near/toward the front of the head
dorsal meaning
on/towards the back (or located above the brain nuclei)
frontal meaning
‘of the front’, or viewing the brain sections from the front
inferior meaning
located below
lateral meaning
towards the side of the body
posterior meaning
located near/towards the tail
superior meaning
located above
ventral meaning
on/towards the belly/side of the animal in which the belly is located, or located below the brain nuclei
medial meaning
middle
what are the senses?
somatosensation (touch), vision, taste, smell, audition (hearing)
what is sensation?
the registration of physical stimuli from the environment by the sensory organs
what is the perception of sensation?
the interpretation of sensations by the brain
what is hapsis?
touch
what is nocioception?
pain & temperature
what is proprioception?
body awareness
what is unilateral damage?
part of the spinal cord is damaged
what does ipsilateral mean?
stays on the same side
what does contralateral mean?
changes to the other side
what is touch?
mechanical stimulation
what is pain?
heat, chemical, or mechanical stimulation
What is limbic proprioception?
muscle or joint simulation
what does receptor field mean?
the area of skin covered by 1 sensory neuron & all it’s dendrites. the smaller the receptor field, the more sensitive it is
what is glabrous skin?
hairless (no hair receptors, so more sensitive to touch)
what is olfaction?
sense of smell
how do we perceive taste?
taste stimuli/tastants are chemicals detected by taste receptors on the tongue
what are our basic tastes?
salty, sour, sweet, & bitter (new flavour discovered = unami)
what is gourmand syndrome?
damage to the frontal lobe in the right hemisphere can make people seek fine food.
what is flavour?
taste & olfaction combined. mastication allows for more flavour
what are orthonasal & retronasal odours?
orthonasal = through nose & retronasal = from the back of the throat
what is synesthesia?
mixing up certain senses (could be caused by the cross-talk of neurons)
what are sound waves?
changes in the air pressure caused by vibrating air molecules. no sound’s perceived unless someone’s there to convert them into an electrical signal
what is the frequency?
the rate at which air molecules vibrate (pitch)
What is the amplitude?
the number of air molecules that are vibrating (loudness). this is denoted by the frequency of action potentials
what are the main parts of the ear?
the outer ear (pinna), the middle ear (eardrum), and the inner ear (cochlea)
what are the ossicles bones?
in the middle ear- the hammer, anvil, & stirup
what is the basilar membrane?
in the cochlea. it has auditory receptor neurons that respond to different frequencies depending on where they are on the basilar membrane.
what are auditory receptor cells?
inner hair cells
where are sounds processed in the brain?
signals from one ear are processed in both hemispheres, but the opposite hemisphere received preferential input
what is sound localization?
integrating information from the 2 ears. this is done by the neurons in the brainstem & midbrain.
what is an audition tonotopic map?
neurons that respond to high-frequency tones are grouped together in primary auditory cortex (and same for low-frequency tones)
what is aphasia?
an inability to understand or produce language (caused by damage to language regions of the brain)
what is Wernicke’s aphasia?
an inability to understand/produce meaningful language
where is Wernicke’s area?
in the left temporal lobe
what is Broca’s aphasia?
the inability to speak fluently
Where is Broca’s area?
the inferior frontal gyrus
where is language in the brain?
the left hemisphere (develops in both hemispheres, but moves at 5yrs)
circannual rhythms
annual rhythm
ultradian rhythms
fluctuate throughout the day
circadian rhythms
fluctuate throughout the day
what are zeitgebers?
environmental/external cues
whats an explanation for SAD?
the lack of light during winter signals hibernation
what is the endogenous circadian clock?
the suprachiasmatic nucleus (in the hypothalamus)
how is melatonin related to the sleep/wake cycle?
during the dark phase of the day/night cycle, the pineal gland secretes melatonin
what happens during NREM sleep?
body temp lowers, heart rate lowers, more growth hormones
what sleeping disorders occur during NREM sleep?
sleepwalking, restless leg syndrome, insomnia, & sleep apnea
what are brain waves like when someone’s sleepwalking?
there’s a combination of delta waves & higher frequency wakeful waves. the cerebellum’s active (controls automatic movement & coordination)
what happens during REM sleep?
become paralyzed, body temp increases and EEG resembles the waking pattern. more likely to report dreaming
what disorders occur during REM sleep?
sleep paralysis, narcolepsy, cataplexy
why do we dream during REM sleep?
high activity in occipital areas (but low in inferior frontal areas)- may explain the high visual imagery & chaotic organisation of dreams.
the cerebral cortex gets signals from the brainstem that generate random images from memory stores.
the 3 main functions of sleep
biological adaptation, body restoration, & memory consolidation
what are the biological adaptations of sleep?
conserving energy, & prey sleep less
what happens when rats are sleep deprived?
there’s an increase of Nitric Oxide Synthase (a predictor of heart disease) & show an immune response similar to stress.
what part of the brain puts us to sleep?
the anterior hypothalamus (preoptic area) promotes sleep. the posterior hypothalamus promotes wakefulness through the reticular activating system
what neurons control our sleep?
regulatory neurotransmitter system- NE, serotonin, & ACh neurons fire during waking. ACh also enhances REM events. descending activity’s needed to inhibit motor neurons during dreaming (may be caused by regulatory hormones)
what are promotors of sleep?
Muramyl peptides (present in sleep-deprived goats), Interleukin-1 (synthesised in glial cells & stimulates the immune system), adenosine (neuromodulator & has inhibitory effect of neurons), melatonin from the pineal body, proteins from gene expression (changes according to sleep pattern)
what is a genotype?
the full set of genes that an organism possesses. genes are organised into chromosomes (23 pairs)
what are the sex chromosomes?
Male genome - XY & female genome - XX
what are the sex (gonadal) hormones)
Androgens (testosterone), estrogens (estradiol) & progesterone
what is Mullerian inhibitory hormone?
inhibits the formation of the Mullerian ducts & retains Wolffian ducts (makes foetus male). Androgens are released pre-natal & 1st-week post-natal to develop the testes
size of the preoptic nucleus in male/female rats
same size at birth, but the male nucleus grows to several times the size
what is sexual dimorphism?
two sexes of the same species exhibit different characteristics
size of INAH3 in males/females
twice as large in males than females
differences in SCN of males/females
male SCN has 2x as many neurons as the female SCN
what are some genetic mutations that result in an ambiguous sexual phenotype?
turners syndrome (XO), congenital adrenal hyperplasia (CAH), androgen insensitivity syndrome (AIS)
what is turners syndrome?
ambiguous sexual phenotype (XO)- results in short stature & lack of sexual development in women
what is congenital adrenal hyperplasia?
ambiguous sexual phenotype (CAH)- high levels of circulating androgens results in a masculine phenotype of XX individuals
what is androgen insensitivity syndrome?
ambiguous sexual phenotype (AIS)- not responsive to circulating levels of androgen, resulting in the feminization of XY individuals
what areas of the brain are involved in sexual behaviour
the hypothalamus is for sexual behaviour, and the amygdala for sexual motivation (from a study on lesioned rats), frontal lobe mediates sexual desires (lesions = aggressive)
What is the reward for completion of sexual behaviour?
the release of the excitatory neurotransmitter dopamine & then oxytocin (relaxing & promotes pair bonding)
what are pheromones?
not perceived consciously as smell, but directly activate the amygdala & hypothalamus
2008 Savic & Lindstrom study
gay women have asymmetric brains like straight men & gay men have symmetric brains like straight women
case study of a patient with amygdala damage
SM - impaired at recognising fear & anger, but not positive emotions
James-Lange theory
emotions result from changes to the body state
the role of the cerebral cortex/frontal lobe in emotions
animals with lesions to the cerebral cortex but intact hypothalamus are aggressive to external stimulus (cerebral cortex mediates emotion from the hypothalamus)
the higher a sever on the spinal cord…
the less fear & anger one feels (interrupts the connection between ANS & brain)
what is a frontal lobotomy?
Moniz- create lesion to frontal lobe to make a person less emotional
why do children have tantrums?
the connections between the frontal lobes & limbic system haven’t developed yet (if the connections don’t develop, it can lead to phobias)
affective (mood) disorder
abnormal regulation of sadness & happiness - linked to decreased levels of serotonin & the link between the amygdala & prefrontal cortex
role of the right hemisphere in emotions
important in the expression & comprehension of emotional aspects of speech, and negative emotions
role of the left hemisphere in emotions
positive emotions
what controls muscles in the face (i.e. when smiling)
neurons that receive input from the cerebral cortex & limbic system (natural smile). a fake smile activates the motor cortex
What does Tibetan monks meditation do?
3x gamma wave activity in frontal & parietal-temporal regions. synchronised gamma waves are associated with binding neural components into a perceptual construct
