The brain Flashcards
Neuron
individual nerve cell that receives, processes, and/or transmits information to other cells
dendrites
Branchlike parts of a neuron that are specialised to receive information
axon
a single, tubelike, extension that transmits neural information away from the soma to the axon terminals
myelin sheath
a white, fatty substance that coats and helps insulate the axon from the activity of other nearby axons, so the message is fast and uninterrupted
axon terminal
The endpoint of a neuron where neurotransmitters are stored and sent to the next neuron
sensory neurons
neurons that carry incoming information from the sensory receptors to the brain and spinal cord
motor neurons
neurons that carry outgoing information from the brain and spinal cord to the muscles and glands
role of the nervous system
receive and process info, and coordinate a response to it
central nervous system
process information received from our internal and external environment and to activate appropriate responses
divisions of the CNS
brain and spinal cord
peripheral nervous system
carries info to the CNS from the body, and from the CNS to the body
brain
controls everything we think, feel and do
spinal cord
receive sensory info from body and sends to brain, receives motor info from brain and sends to body
divisions of the PNS
somatic and autonomic
Somatic NS
detects sensory info and carries to CNS, and controls voluntary motor movement
Autonomic NS
That controls the glands and muscles of the internal organs, like the heart, largely automatic
Divisions of the ANS
sympathetic, parasympathetic, enteric
Sympathetic NS
Activates internal muscles, glands and organs to prepare the body to deal with vigorous activity or a stressful/threatening situation
Parasympathetic NS
maintains the internal body environment in a balanced state of normal functioning - ‘homeostasis’
Enteric NS
Controls the gastrointestinal system
3 main areas of the brain
hindbrain, midbrain, forebrain
3 structures of the hindbrain
medulla, pons, cerebellum
medulla
the base of the brainstem; controls heartbeat and breathing (hindbrain)
pons
involved in sleep, dreaming and arousal from sleep (hindbrain)
cerebellum
Balance and coordination (hindbrain)
midbrain
connects the lower and upper structures of the brain, helps orient us
reticular formation
helps screen incoming information so as not to overload the brain, helps regulates arousal and muscle tone
3 structures of the forebrain
cerebrum, thalamus, hypothalamus
cerebrum
The cerebrum is responsible for almost everything we consciously think, feel and do (forebrain)
hypothalamus
a vital role in maintaining homeostasis through regulating the release of hormones and behaviours associated with basic needs, e.g. hunger, thirst, sleep (forebrain)
thalamus
filters information from almost all the sense receptor sites (except the nose), then passes it to relevant areas of the brain for further processing (forebrain)
contralateral functioning
each hemisphere of the cortex receives information from and controls the opposite side of the body
hemispheric specialisation
the idea that one hemisphere has specialised functions or exerts greater control over a particular function
left hemispheric specialisation
verbal, analytical, logic, reasoning, planning
right hemispheric specialisation
non verbal, spatial and visual thinking, recognising faces, appreciating art, creativity
4 lobes of the brain
frontal, parietal, occipital, temporal
frontal lobe
associated with reasoning, planning, parts of speech, movement, emotions, and problem solving
primary motor cortex
the section of the frontal lobe responsible for voluntary movement
broca’s area
controls language expression - an area, usually in the left frontal lobe, that directs the muscle movements involved in speech
parietal lobe
A region of the cerebral cortex whose functions include processing information about touch and sensation
primary somatosensory cortex
the region of the parietal lobe whose primary input is from the somatosensory system
temporal lobe
A region of the cerebral cortex responsible for hearing and understanding language
primary auditory cortex
the region of the temporal lobe whose primary input is from the auditory system
Wernicke’s area
a brain area involved in language comprehension and expression; located in the left temporal lobe
occipital lobe
A region of the cerebral cortex that processes visual information
primary visual cortex
the region of the occipital lobe whose primary input is from the visual system
Synaptogenesis
formation of new synapses
synaptic pruning
a process whereby the synaptic connections that are not used are lost
sudden onset brain injury
occurs abruptly (blow to the head, car accident, etc.)
insidious onset brain injury
gradually develops over time (tumour, Parkinson’s)
acquired brain injury
Brain damage that occurs as a result of injury or physical trauma to the brain after birth
traumatic brain injury
A type of ABI caused by a blow to the head, or by the head moving forwards and backwards rapidly
frontal lobe biological changes
Motor activity and ordinary voluntary movements reduced, facial expressions tend to become blank
frontal lobe psychological changes
tendency to not care about emotional things, lack of concern about past or present, verbal and physical aggressiveness, unable to plan activities
frontal lobe social changes
Personality changes leading to socially unacceptable behaviour > can lead to a breakdown in friend and family relationships, loss of social support, unemployment, isolation
broca’s aphasia
condition resulting from damage to Broca’s area, causing the affected person to be unable to speak fluently, to mispronounce words, and to speak haltingly
wernicke’s aphasia
condition resulting from damage to Wernicke’s area, causing the affected person to be unable to understand or produce meaningful language
brain plasticity
The capacity for the brain to alter its structure and function
Rerouting
an undamaged neuron that has lost a connection with an active neuron may seek a new active neuron and connect with it instead
sprouting
the growth of additional branches on axons or dendrites to enable new connections
long term potentiation
gradual strengthening of the connections among neurons from repetitive stimulation
long term depression
the long-lasting decrease in the strength of synaptic transmission
ways to maximise brain function
mental stimulation, diet, exercise
Mental stimulation
any activity that activates or enriches the mind
Diet
A varied diet can support a healthy brain by enhancing synaptic transmission and cognitive function
Exercise
physical activity can reduce age-related decline in the brain
symptoms of a stroke
Face, Arms, Speech, Time (FAST)
epilepsy
neurological disorder that causes sudden, intense bursts of brain activity, resulting in seizures
typical symptoms of epilepsy
convulsions accompanied by shaking and thrashing movements, salivation, foaming at the mouth and loss of body functions.
risks associated with epilepsy
seizures over 5 minutes, seizures can occur at dangerous times
diagnosing epilepsy
an EEG can detect abnormal brain waves, MRI and CT scan can identify affected brain regions
treatment of epilepsy
antiepileptic drugs, surgery to remove affected areas or vagus nerve stimulator if serious
vagus nerve stimulator
device implanted under the skin that sends regular, mild electrical impulses to the brain to control seizures
CTE
chronic traumatic encephalopathy
Chronic Traumatic Encephalopathy (CTE)
a progressive, degenerative condition involving brain damage resulting from multiple episodes of head trauma
typical victims of cte
contact sports stars, domestic violence victims, army personnel are more likely to be diagnosed
CTE stage 1
headache, loss of attention and concentration, irritability
CTE stage 2
rage, impulsivity, depression
CTE stage 3
executive dysfunction, cognitive impairment
CTE stage 4
dementia, word-finding difficulty, aggression
CTE biological markers
a build up of tau proteins which prevents neurons from staying alive and functioning properly
diagnosis of CTE
CTE cannot currently be conclusively detected while the person is alive, can only be diagnosed with autopsy after death
treatment of CTE
no current cure, most treatment aims at improving behavioural and cognitive function, medication can help
prevention of CTE
the simplest way to prevent CTE is to prevent trauma to the head
