Neuro to learn Flashcards

Question

Brain changes in schizophrenia

Answer 1

* Enlarged ventricles * Reduced grey matter * Decreased temporal lobe volume (auditory hallucinations) * Reduced hippocampal formation, amygdala, parahippocampal gyrus and prefrontal cortex

Answer 2

typical and atypical antipsychotics typical - antagonise D2 receptors in all dopamine pathways (Parkinsonism side effect) atypical * Lower affinity for D2 (dopamine) receptors * Milder side effects as dissociate rapidly from D2 receptor * Also block 5HT2 (serotonin) receptors – less parkinsonism

Answer 3

hyperprolactinaemia * Dopamine normally inhibits prolactin release from the pituitary. * DA antagonists, which lower DA lead to loss of DA’s inhibitory function, and therefore increased prolactin levels. * This can lead to: amenorrhoea, galactorrhoea, decreased fertility, reduced libido and long term can lead to osteopenia/osteoporosis

Answer 4

ventral ramus (suppling brachial and lumbosacral plexus) and the dorsal ramus (supplies intrinsic muscles of the back)

Answer 5

Hirshprungs- certain segment sof the gut will have no enteric nervous system- constipation Di Georges- not T cell education in the thymus

Answer 6

1. Astrocyte stores glycogen 2. Astrocyte produce lactate from the breakdown of glycogen 3. Lactate then shuttled across with H+ via the **MCT1** transporter on the astrocyte and the **MCT2** transporter on the neuron 4. Lactate is then converted to pyruvate 5. Pyruvate metabolism releases ATP which can be used as an energy source of the neurone

Answer 7

integral ion channel – activation of receptor, ion channel opens, inward movement of Na+  depolarisation **AMPA receptors** Permeable to Na and K+ **NMDA receptors** Permeable to Na ,K+ and Ca2+ Calcium permeability important **Kainate receptors** Permeable to Na and K+ Reveal Answer

Answer 8

The inhibitory relay neurone then releases glycine which inhibits the motor neurone to the antagonist muscles (hamstring) therefore allows the hamstrings to relax

Answer 9

Tau protein *usually stabilise microtubules*

Answer 10

protein alpha-synuclein, a cytoplasmic protein associated with synaptic vesicles.

Answer 11

FTD-tau FTD-U (ubiquitin)

Answer 12

3 behavioural presentations of FTD Apathetic Disinhibited Stereotypic

Answer 13

levator palpebrae superioris (LPS)

Answer 14

superior tarsal muscle --\> causes ptosis if sympathetic innervation affected e.g. pancoast tumour

Answer 15

quadriceps

Answer 16

(L3 level- L3 myotome = major input to quadriceps) 1. Patellar ligament in tapped by tendon hammer 2. Stretching of fibres of the quadriceps is detected by muscle spindles found within the quad muscle 3. Muscle spindles detect muscle length= stretch 4. Stretched detected by muscle spindle is conveyed to the spinal cord via first order sensory afferent (cell body found in the dorsal root ganglion) 5. This first order sensory afferent enters the dorsal horn and projects down to the ventral horn and synapses onto a lower motor neurone 6. LMN sends its axon down into the ventral root and down to the quadriceps muscle itself causes twitch 7. What about the hamstrings? Need them to stop antagonising the action of the quads If the quads are contracting this would cause the hamstring to contract and this would result in no movement at all  agonist+ antagonist contraction= no movement Therefore: 1. L5 myotome supplies the hamstring 2. First order sensory neurones sending info from the muscle spindle in the quadricep descends down from L3 to L5 and synapse with inhibitory interneurons 3. Inhibitory interneurons inhibit LMN supplying the hamstring (selective inhibition of hamstrings) 4. Therefore antagonists effect of hamstrings muted and the patellar reflex can cause full extension at the knee

Answer 17

collection of cell bodies of LMN that will distribute along the vagus nerve and innervates muscles of the vocal cords and pharynx) * Bilateral innervation * Required because nucleus ambiguous controls swallowing necessary for survival

Answer 18

1. Cortical lesion e.g. stroke destroys excitatory corticospinal tracts and the descending inhibitory inputs 2. Initially lower motor neurone will go into a state of ‘spinal shock’ * Frequency of AP running along LMN will decrease significantly * Therefore tone of muscle supplied by this LMN will increase 3. As time goes on the LMN starts to wake up * Realises it still has the excitatory input of the muscle spindles (sensory afferents) 4. However, **loss of CST**- therefore no voluntary movements 5. Lost descending inhibitory influences 6. Therefore breaks have been taken off LMN, therefore it will fire off more frequent AP, leading to more frequent muscle contracts = increased muscle tone 7. Loss of net inhibition therefore increase excitation

Answer 19

This is due to fibres from the corticospinal tract showing **less somatotopic organisation** in the internal capsulee.g. face and lower limb fibres mixes

Answer 20

Receives this info from the **primary sensory cortex and the spinocerebellar tract** (information from proprioceptors in the muscles up the spinal cord into the cerebellum) Cerebellum than communicates back to the primary motor cortex (via the thalamus)

Answer 21

double decussation of nerve fibres

Answer 22

explains why spinothalamic and dorsal column modalities can be lost at different spinal cord levels - axons within Lissauer's tract are first order sensory neurones which ascend around 2 segments before synapse onto 2nd order

Answer 23

if **cortical spinal tracts** not suppplied by the **pontine branches** on the basilar artery * Cortical spinal tract death --\>no movement * Midbrain still supplied so can move eyes *

Answer 24

posterior communicating arteries

Answer 25

nimlodopine - pfrevent vasospasm

Answer 26

Decreasing consciousness Brainstem signs Recent seizure CT head can be useful to find contraindications to doing an LP But a normal CT may not mean that an LP is safe to perform

Answer 27

tetracyline (ceftrioxone)

Answer 28

**Inputs to the RF which keeps us conscious** * Excitatory (cholinergic) input from the **cerebral cortex** to the reticular formation in the brainstem * **Sensory input** (e.g. first/2nd order sensory neurones from the body) to the RF **Outputs from the RF** to the cortex to keep us conscious * RF provides outputs which have to pass the **thalamus** (cholinergic synapse) and project up to the cortex * **Glutaminergic** projections up to the cortex * RF also provides outputs which pass the **hypothalamus** (cholinergic synapse) which project up to the cortex * **Histinermergic** projections up to the cortex * RF sends outputs to the **basal forebrain** (cholinergic synapse) nuclei which also project up to the cortex * **Cholinergic** projections up to the cortex Both input and output projections are excitatory- positive feedback loop (cholinergic – ACh transmitter) Transmitters released in the cortex maintain awake fullness

Answer 29

Supplies the lateral frontal lobe e.g. primary motor cortex and the Broca’s area Examples of superior division problems * Contralateral face and arm weakness * Broca’s (Expressive) aphasia * Only if occurs on the LHS

Answer 30

Examples of inferior division problems e.g. primary sensory cortex and Wernicke’s area * Contralateral face and arm loss of sensation * Wernicke’s aphasia * Homonomous hemianopia if both optic radiations are damaged or a quadrantanopia if just one radiation is affect * Without macula sparing (only macula sparing if PCA stroke)

Answer 31

Medial Longitudinal Fasciculus

Answer 32

multiple sclerosis

Answer 33

***Jendrassik*** maneuver is a medical maneuver wherein the patient clenches the teeth, flexes both sets of fingers into a hook-like form, and interlocks those sets of fingers together. The tendon below the patient's knee is then hit with a reflex hammer to elicit the patellar reflex.

Answer 34

dorsal column- lower body

Answer 35

dorsal column- upper body

Answer 36

is a test of the body's sense of positioning (proprioception), which requires healthy functioning of the dorsal columns of the spinal cord. The Romberg test is used to investigate the cause of loss of motor coordination (ataxia).

Answer 37

Supraspinous ligament Interspinous ligament Ligamentum flavum

Answer 38

Total sensory loss ipsilateral (left) L3 (1 mark) Ipsilateral (left) dorsal columns L3/4 down (1 mark) Contralateral (right) spinothalamic L4/5 down (1 mark)

Answer 39

Left homonymous hemianopia

Answer 40

sign of parkinsons your muscle will be stiff, like in other forms of rigidity. But you might also have tremors in the same muscle when it's at rest. Cogwheel rigidity can affect any limb, but it's most common in the arms. It can affect one or both arms.