Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

LCRS Y2 > Neuro > Flashcards

Neuro Flashcards

1
Q

Identify and summarise structure of the thalamus

A

Above pons, beneath corpus callosum. Pituitary gland is closely collaborating with it, sitting posteriorly and inferiorly to it.
Sits just beneath the lateral ventricles, and is divided down the middle by the third ventricle.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Explain functional significance of thalamic nuclei

A

“Clapham junction of the brain” = Relay site for inputs and outputs. Relays all sensory information except for olfactory.
Enhances or restricts signals, depending on the location in the thalamus.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

explain the relationship between the intralaminar nuclei, reticular nucleus and the reticular formation

A

Both the intralaminar and reticular nuclei receive information from the ARAS (Ascending Reticular Activating System) of the reticular formation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Where is all touch and proprioception information (somatosensory pathway) relayed in the thalamus?

A

Ventral posterior lateral nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are intralaminar nuclei?

A

Nuclei that project to various medial temporal lobe structures like the amygdala, hippocampus and basal ganglia. It consists of mostly glutamatergic neurons.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the reticular nuclei?

A

The outer coverings of the thalamus. Consists of mostly GABAergic neurons. Unlike thalamic nuclei it largely connects medial rather than distal regions, so largely connects with other thalamic nuclei. It therefore modulates thalamic activity.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the reticular formation?

A

Integrated pathways along the brainstem. Precise anatomy is not particularly well-known, so generally the area of the brainstem which we don’t know about we call the reticular formation. Involved in arousal and wakefulness, consciousness.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the 4 F’s related to the hypothalamus?

A

Fighting
fleeing
feeding
fucking

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the function of the hypothalamus?

A

Controlling autonomic response to the outside world.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the paraventricular nucleus?

A

It sends projections to autonomic nervous system and to posterior pituitary gland. Contains parvocellular and magnocellular neurons. Parvocellular neurons tend to be travel to sites of autonomic nervous system such as heart, kidney and arteries, whereas magnocellular neurons tend to be more secretory and travel to posterior pituitary gland.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the suprachiasmatic nucleus?

A

Sits right above the optic chiasm and is involved in circadian rhythm, controlling sleep-wake cycles. It is also connected to the pineal gland (which secretes melatonin).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Basal ganglia: recall the component structures of the basal ganglia

A 
Includes: 
Caudate nucleus
	Lentiform nucleus (putamen + external globus pallidus)
	Subthalamic nucleus
	Substantia nigra
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Parkinson’s disease: recall the pathophysiology and clinical signs of Parkinson’s disease

A

Classically the primary pathology involves the neurodegeneration of the dopaminergic neurons that originate in the substantia nigra and project to the striatum

Bradykinesia
Hypomimic face 
Akinesia
Rigidity 
Tremor at rest
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Huntington’s disease: recall the pathophysiology and clinical signs of Huntington’s disease

A

Degeneration of GABAergic neurons in the striatum, caudate and then putamen

Choreic movements (Chorea) 
Speech impairment
Difficulty swallowing
Unsteady gait
Later stages, cognitive decline and dementia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Cerebellum: explain how the cerebellum contributes to coordination of movement, recognise the relevance of pathways into and out of the cerebellum, recognise how cellular organisation of the cerebellum relates to its functioning

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Ataxia: define ataxia and explain how lesions in specific areas of the cerebellum relate to effects in specific parts of the body

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Neuromuscular junction: recall the structure and function of the neuromuscular junction

A

When an action potential arrives at the MNJ, Ca2+ influx causes ACh release. ACh binds to receptors on motor end plate.
Ion channel opens – Na+ influx causes action potential in muscle fibre.

A specialised synapse between the motor neuron and the motor end plate, the muscle fibre cell membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Motor neurons: summarise the organisation of alpha motor neurons within the spinal cord

A

Organised in pools in the ventral horn; one pool contains neurons that innervate one muscle.
Organisation in the ventral horn:
Extensors are more ventral, flexors are more dorsal.
Proximal is more medial and more distal is lateral.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Motor units: define the term “motor unit” and compare different types

A

Smallest functional unit with which to produce force.
There’s slow, fast (fatigue resistant) and fast (fatiguable)
Type I: slow twich, fatigue resistant
Type IIa: fast twitch, fatigue resistant
Type IIb: fast twitch, high fatigue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Spinal motor tracts: summarise the functional organisation of the spinal cord (motor tracts)

A
21
Q

Spinal reflexes: recognise a range of spinal reflexes, including stretch reflex, flexion / withdrawal reflex, crossed extension reflex); distinguish hypo- and hyperreflexia; explain the concept of supraspinal control of reflexes

A
22
Q

What are the superior and inferior colliculi?

A

The superior colliculus is involved in eye and neck movement whereas the inferior one is involved in auditory responses.
They are the 4 bumps that sit right under the thalamus.

23
Q

What is the cerebral peduncle?

A

It’s a corticospinal fibre tract that holds the cerebrum to the brainstem.

24
Q

Which nerve has its origin in the midbrain and what does this nerve control?

A

The oculomotor nerve (III) and it controls eye movement.

25
Q

What nerve has its origin in the pons and what does this nerve control?

A

The trigeminal (V) nerve, which controls the muscles of mastication/chewing.

26
Q

Which nerves have an origin in the ponsomedullary junction? What do these nerves control?

A

Abducens (VI), which controls the lateral rectus muscle (eye movement)
Facial (VII), which controls the musculature of face
Vestibulocochlear (VIII), which controls balance and hearing

27
Q

Which nerves have their origin in the medulla? What do these nerves control?

A

Glossopharyngeal (IX), which controls tongue and pharynx for swallowing and mastication
Vagus (X), PNS innervation to viscera
Accessory (XI), which controls the sternocleidomastoid and the trapezius
Hypoglossal (XII), which controls intrinsic muscles of tongue

28
Q

Explain functional classification of nerves.

A

General somatic afferent (GSA) – general sensation from skin. e.g. skin and mucous membrane sensation.

General visceral afferent (GVA) – general sensation from viscera. e.g. GI tract, heart, lungs, vessels.

Special somatic afferent (SSA) – senses derived from ectoderm (e.g. sight, sound, balance).

Special visceral afferent (SVA) – senses derived from endoderm (e.g. taste, smell).

General somatic efferent (GSE) – skeletal muscles.

General visceral efferent (GVE) – smooth muscles of gut and autonomic motor.

Special visceral efferent (SVE) – muscles derived from pharyngeal arches. e.g. chewing, facial expression, swallowing, vocal sounds and turning of head

29
Q

What are the different types of somatosensory information our somatosensory systems can interpret?

A

Mechanical
Thermal
Proprioceptive
Nociceptive (damaging and noxious stimuli)

30
Q

Explain the organisation of the brainstem with reference to its development.

A

You have a neural tube with a dorsal side (alar plate) and ventral side (basal plate). The dorsal side contains the sensory fibres, so the GSA and GVA. The ventral contains the efferents so the GSE and GVE.

The alar plate then splits in half, and each side moves laterally. This is why we later get afferent fibres on both sides

31
Q

Looking at a transverse section, give one significant defining feature telling you where you are situated in the brainstem for;

  • Midbrain
  • Pons
  • Medulla
A

Midbrain: Mickey Mouse ear feature OR presence of highly pigmented substantia nigra
Pons - transverse fibres OR fourth ventricle as pons is the floor of the fourth ventricle
Medulla - presence of inferior olivary nucleus (squiggly line)

32
Q

Explain how the neural tube develops from the neuroectoderm and give an example of a clinical condition which results from abnormal development.

A

A proliferation of the ectoderm forms the neural plate.
The neural plate folds up on the sides and fuses dorsally, creating a neural tube. (or neural canal)
A little tip of the dorsal part of the neural canal then forms the neural crest.

Neural tube = all CNS cells (the wall of the neural tube is the neuroepithelium).

b. Neural crest = all PNS cells.

33
Q

Explain what is meant by the term neural crest cells, and give examples of their developmental fates.

A

The cells that become all cells that constitute the PNS. 4 types of cells differentiate from the neural crest cells:

o Sensory neurones of dorsal root ganglia and cranial ganglia.

o Postganglionic autonomic neurones.

o Schwann cells – myelinate axons in PNS.

o Non-neuronal derivatives – e.g. melanocytes.

34
Q

Summarize the cellular basis of formation of the ependymal, grey matter and white matter regions of the spinal cord, and the separation of the grey matter into sensory and motor areas.

A

The neuroepithelium (outermost layer of neural canal) keeps undergoing mitosis, with the youngest and biggest cells towards the inside of the neural canal.

Once a cell has undergone mitosis, one daughter cell moves up towards the outside and develops into a neuroblast. These cells form axons and dendrites, axons directed away from inside of neural canal.

Eventually you end up with three layers; the inner ependymal layer undergoing mitosis (germinal), the next containing soma (mantle) and the next containing axons (marginal).

35
Q

Summarize how cerebral cortical layers form from the neuroepithelium.

A

Development of the Cortex

§ The brain has a core of white matter with grey matter on the outside.

o Grey matter = nuclei that have migrated from the inner membrane of the neural tube.

§ Neuroblasts proliferate at the inner membrane.

o Some neuroblasts will stay in the middle and form basal ganglia.

o Some neurones then migrate towards the outer membrane.

§ Migration occurs by neuroblasts attaching themselves to radial glial cells – these cells have their soma attached to the inner membrane and have a single long process to the outer membrane.

§ The neurones then climb towards the outer membrane.

§ These proliferations and migrations occur in waves to form layers of the cortex (1st, 2nd, etc.) until you reach 6 layers – each layer is unique.

36
Q

Explain how an understanding of developmental neurobiology may help in the treatment of neurological disorders.

A

Neural development involves several complex, timed processes which may be disrupted by genetic or environmental abnormalities.

§ This occurs early in gestation and pregnancy.

§ Abnormalities:

o Schizophrenia – malfunction of neural development.

o Spina bifida – deficiency of folic acid.

37
Q

What are the stages of sleep?

A

Stage 1&2: NREM
Stage 3&4: NREM
Stage 5: REM (EEG similar to awake state, signifciant changes OEG or eye movement)

38
Q

What is the reticular activating system?

A

a polysynaptic network in the core of the midbrain, pons and upper medulla.
controls consciousness, stems from brainstem and travels upwards into cerebral cortex.

39
Q

What areas work together with the reticular activating system in controlling wakefulness?

A

Two parts of the hypothalamus, one + acting and one - acting:

  • Lateral Hypothalamus (LH): promotes wakefulness (orexin/hypocretin is the neurotransmitter important in this pathway). In narcolepsy orexin seems to be reduced.
  • Ventrolateral pre-optic nucleus (VLP): promotes sleep
And then, the basis of all conscious experience:
Suprachiasmatic nucleus (SCN): synchronises sleep with falling light levels
40
Q

What are the effects of sleep deprivation?

A

Psychiatric and neurological (sleepiness, irritability, stress, mood fluctuations)
Neurological (impaired attention, memory, executive function, neurodegenation?)
Somatic (glucose intolerance, reduced leptin/increased appetite, impaired immunity, increased risk of cardiovascular disease and cancer)

41
Q

How is sleep regulated accurately?

A

After sleep loss: reduced latency to sleep (you fall asleep more easily)
If NREM sleep lost -> more NREM sleep
If REM sleep lost -> more REM sleep

42
Q

What are causes of chronic insomnia?

A

Physiological e.g. sleep apnoea, chronic pain.

Brain dysfunction e.g. depression, fatal familial insomnia (progressive prion disease), night working

43
Q

What are the treatments for insomnia?

A

Sleep hygiene (routine, only going to bed when tired, no caffeine/alcohol/nicotine)
Hypnotics (most enhance GABAergic circuits)
Sleep CBT

44
Q

What is REM sleep behaviour disorder?

A

Shouting or acting out of dreams
Often associated with Lewy-body dementia.
Sleep disorders are often associated with neurodegeneration, at the same time as neurodegeneration is associated with disturbed sleep

45
Q

Altered conscious level: define the main altered states of consciousness and explain the Glasgow Coma Score (GCS)

A

Altered states of consciousness:

  • Contusion (bruising or bleeding in certain area of brain)
  • Concussion (sustained and homogenous disturbance of whole brain)
  • Delirium - acute confusion (disorientation, confusion, inattentiveness)
  • Stupor - no response to anything but pain

Glasgow Coma Score meaures eyes opening, verbal responses and motor responses on a scale of 1-4, 1-5 and 1-6. A score of 3 = brain death.
Persistent vegetative state and brain death are two things that can be measured using the GCS.

46
Q

What is consciousness?

A

the brain state that enables us to experience the world around us and within one-sel

It is the feeling of “what it is like” to be someone doing something at a given time

There is a distinction between levels (alertness) vs. contents (subjective experience) of consciousness.

o Alertness involves the reticular formation; this regulates vital functions. It projects into the thalamus and the cortex (allowing it to ‘control’ whether or not sensory signals reach cortical sites of conscious awareness – such as the posterior parietal cortex).

47
Q

What is the reticular formation?

A

The RF includes the ascending pathways in the RAS (reticular activating system). It receives input from all sensory pathways.
Touch and pain – from ascending tracts.

o Vestibular – from medial vestibular tracts.

o Auditory – from inferior colliculus.

o Visual – from superior colliculus.

o Olfactory – from medial forebrain bundle.

It contains NA (Nucleus Coeruleus projecting into cerebral cortex), dopaminergic (ventral tegmental nucleus projecting into cerebral cortex) and cholinergic neurons (projecting into thalamus).

48
Q

What’s the difference between level of arousal and contents of arousal?

A 
Level = alertness
Contents = subjective experience
49
Q

How is level of arousal measured?

A

EEG waves
Delta waves are the ones with highest amplitude and lowest frequency (4-8Hz) and are associated with sleep

Beta waves have lowest amplitude and highest frequency (13-30Hz) and are associated with the normal waking conscious state.

LCRS Y2 (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions