functional neuroscience anatomy of the brain

Question 1

what does the human brain use 3lbs of tissue for?

Answer 1

to process all emotions and solve equations all of these functions occur within the 100bill neuron’s and 10trill neuroglia that comprise the human brain

Question 2

why are the frontal lobes expanded?

Answer 2

because they are associated with higher executive functions such as self control, planning,reasoning and abstract thought

Question 3

state the 4 roles of the cerebral cortex

Answer 3

-to receive sensory info
-sends messages to move skeletal muscles
-integrates incoming and outgoing nerve impulses
-peforms activities such as thinking, learning and remembering

Question 4

cerebral cortex vs cerebrum

Answer 4

the outer layer of the brain that lies on the top of our cerebrum and the cerebrum is the largest part of our brain

Question 5

what is the cerebral cortex?

Answer 5

the seat of intelligence as because of neutrons in the cortex we are able to read,write,speak and remember

Question 6

what does the cerebrum consist of?

Answer 6

an outer cerebral cortex which is the internal region of white and grey matter nuclei deep within the white matter

Question 7

what happens during the embryonic developments of the cerebral cortex?

Answer 7

the grey matter of the brain develops faster than the white matter because the cortical region rolls and folds on itself and during the growth process convulsions and grooves are created in the cortex

Question 8

what are the folds in the cortex called?

Answer 8

the folds are called gyri,the deepest ones are known as fissures, the shallower grooves between the folds are called sulci

Question 9

why does the cerebral cortex have subdivisions?

Answer 9

-the cortex receives info from different parts of the brain and from the environment and this info is processed in different regions of the brain
-the different regions then send commands to different brain regions, muscle groups or sensory organs

Question 10

state the different parts of the cerebral cortex

Answer 10

-The 1o visual area which is located at the posterior tip of the occipital lobe mainly on the medial surface
-The 1o gustatory area which is located just inferior to the 1o somatosensory area
-The 1o auditory area which is in the superior part of the temporal lobe
-The 1o olfactory area which is in the inferomedial temporal lobe

Question 11

what is the basal nuclei?

Answer 11

-the basal nuclei are conspicuous centres of cell bodies deep in the cortex

Question 12

what is the role of the basal nuclei?

Answer 12

-there are 3 basal nuclei which help to initiate abdominal terminate movements, suppress unwanted movements and regulate muscle tone
-the basal nuclei also controls subconscious contractions of skeletal muscles such as automatic arm swings

Question 13

what neurones are found in the cerebral cortex?

Answer 13

-pyramidal neurons
-inhibitory interneurons
there are also apical dendrites found which form multiple branches
-networks of connected excitatory pyramidal neurones and inhibitory interneurons are fine-tuned to regulate cortical function

Question 14

what is the limbic system?

Answer 14

a ring of structures on the inner border of the cerebrum and floor of the diencephalon that encircles the upper part of the brain stem
-it does not represent any one part of the braun but is more of a functional system composed of part of the cerebral cortex, diencephalon and midbrain

Question 15

what are the main regions of the limbic system?

Answer 15

-amygdala
-hippocampus
-cingulate gyrus
-fornix

Question 16

what is the function of the limbic system?

Answer 16

it is sometimes called the emotional brain because it plays a primary role in promoting a range of emotions such as pleasure, pain,affection and fear
-together with the cerebrum the limbic system also functions under memory

Question 17

state the diseases of the cerebral cortex

Answer 17

-alzheimers disease(AD)/dementia
-seizures and epilepsy
-schizophrenia
-cerebrovascular accidents (stroke)

Question 18

what happens in the brain of someone with Alzheimer’s disease?

Answer 18

-the cortex shrivels up, damaging areas involved in thinking, planning and remembering
-ventricles are filled with cerebrospinal fluid and grow larger
-the hippocampus shrinks severely

Question 19

what happens to cognition in people with AD?

Answer 19

cognition is affected which affects mental processes such as memory,producing and understanding language, solving problems and making decisions

Question 20

what can AD eventually lead to?

Answer 20

dementia which results in a loss of cognitive ability

Question 21

what type of disease is AD?

Answer 21

AD is a neurodegenerative disease and it can lead to neuronal death (neurodegeneration)

Question 22

what happens in neurodegeneration?

Answer 22

neuronal death occurs in specific brain regions e.g the hippocampus and the basal forebrain ad at the end stage the brain shows dramatic shrinkage, there is no cure or successful therapy

Question 23

what are the pathological features of AD?

Answer 23

-there is a loss of neurones particularly this that produce acetylcholine
-threre is extracellular amyloid plaques, consisting of deposits of B-amyloid proteins known as Aβ
-there are intraneuronal neurofibrillary tangles, comprising filaments of a phosphorylated form of a microtubule-associated protein (Tau)
-it is unsure as to whether Aβ and Tau are the cause of the disease or a result of the disease

Question 24

what are the current therapeutic options for AD?

Answer 24

-to replace acetylcholine by giving drugs that prevent the breakdown of acetylcholine e.g Ach esterase inhibitors there is also donepezil,galantamine and rivastigmine
-strategies to target b-amyloid have failed so far

Question 25

what are seizures?

Answer 25

a condition that results in large groups of neutrons being active together or in synchrony and discharging in high frequency patters which never occur during normal behaviour

Question 26

what is epilepsy?

Answer 26

condition associated with the repeated occurrence of seizures

Question 27

what are the causes of seizures/epilepsy?

Answer 27

tumours,trauma,infection,vascular disease

Question 28

what are the different types of epilepsy?

Answer 28

generalised-where the entire cerebral cortex is affected, there is complete behaviour disruption and consciousness loss
partial-there is abnormal sensation or aura in the circumscribed cortex area
absence-there is less than 30secs generalised

Question 29

what are the main epileptic drugs that are in current use?

Answer 29

-carbamazepine
-phenytoin
-valproate
-ethosuximide
-benzodiazepines
if these drugs do not work there needs to be a surgical resection of the affected part of the cortex

Question 30

what are the 3 main mechanisms current anti epileptic drugs are thought to act by?

Answer 30

-reducing electrical excitability of cell membranes, mainly through the use of a dependant block of sodium channels
-enhancing GABA-mediated synaptic inhibition, this may be done by an enhanced postsynaptic action of GABA by inhibiting GABA transaminase or inhibiting GABA uptake into neurone and glial cells
-inhibiting T-type calcium channels (is important in controlling the absence of seizures)

Question 31

what mechanisms to newer anti epileptic drugs act by?

Answer 31

newer anti epileptic drugs act by other mechanisms and drugs that block ionotropic glutamate receptors are effective in animal models but are unstable for clinical use

Question 32

what is schizophrenia (SZ)?

Answer 32

-condition characterised by a loss of contact with reality and a disruptions of thought, perception,mood and movement it is a type of psychosis and has positive and negative symptoms

Question 33

what are the drugs that SZ is treated by classed as?

Answer 33

-antipsychotics they are also known as neuroleptic drugs or anti-schizophrenic drugs

Question 34

how do antipsychotic drugs for SZ work?

Answer 34

-they are predominantly dopamine receptor antagonists e.g drugs like Haloperidol
-they can also act on other targets e.g (5-HT) receptors and this involves drugs such as clozapine
-these drugs do have side effects and issues with their efficacy

Question 35

define pathophysiology…

Answer 35

the disordered physiological processes associated with disease or injury.

Question 36

describe the pathophysiology of SZ

Answer 36

-deficits in cognitive processes mediated by the circuitry of the dorsolateral prefrontal cortex (DLPFC)
-alterations in dopamine,glutamate and GABA neurotransmission are also implicated

Question 37

what are the positive symptoms of SZ?

Answer 37

-delusions
-hallucinations
-disorganised speech
-grossly disorganised or catatonic behaviour

Question 38

what are the negative symptoms of SZ?

Answer 38

-reduced expression or emotion
-poverty of speech
-difficulty in initiating goal-directed movements
-cognitive/memory impairment

Question 39

what are cerebrovascular accidents (CVA)/stroke?

Answer 39

CVA/stroke is a sudden and severe loss of central nervous system function due to decreased blood flow to part of the brain
-damage to part of the brain is caused by interruption to its blood supply or leakage of blood outside of the vessel walls

Question 40

what does the functional consequence of CVA dependent on?

Answer 40

the part of the brain the CVA occurs

Question 41

what are the ways to manage stroke?

Answer 41

-thrombolytic-a tissue plasminogen activator(altepase)
-anticoagulants (e.g heparin, warfarin)
-antiplatelet therapy(e.g aspirin or clopidogrel)
-hypertension treatment(with thiazide diuretic or ACE inhibitors0
-treatment of hyperlipidemia-statins