Central Nervous System Disorders – Lecture Flashcards

A comprehensive set of practice questions covering CNS anatomy, glia, brain regions, neurotransmitters, and the economic and prevalence context of neurological and mental health disorders.

What are the four main categories by which we classify neurological disorders?

Sudden onset; Intermittent and unpredictable; Progressive; Stable but with changing needs.

Give an example of a sudden onset neurological condition.

Stroke, traumatic brain injury, spinal injury, or meningitis.

Give an example of an intermittent and unpredictable neurological condition.

Epilepsy or migraine.

Give an example of a progressive neurological condition.

Neurodegenerative diseases such as Alzheimer's disease.

Give an example of a condition that is stable but with changing needs.

Narcolepsy, cerebral palsy, or Tourette’s syndrome.

What percentage of global disease prevalence do neurological and mental health conditions together account for?

About 13%.

What two major divisions make up disorders of the nervous system, and what do they include?

Neurological illnesses (affecting nervous system structure/function) and mental health conditions (psychological and emotional well-being).

Name three types of changes that can underlie neurological disorders.

Structural changes in the brain; changes in electrical signaling; biochemical changes (signaling environments).

What is the role of the myelin sheath in neurons?

Insulates axons to speed electrical signal transmission; demyelination slows or disrupts signaling.

Why can neurons be slow to recover after damage?

Most neurons are non-dividing (non-mitotic), so regeneration is limited.

What are the three main glial cell types, and what is their general role?

Astrocytes (support neurons and maintain chemical environment), Microglia (immune-like immune responses and debris clearance), Oligodendrocytes (form CNS myelin).

Where are protoplasmic and fibrous astrocytes found, and how do they differ?

Protoplasmic astrocytes are in gray matter; fibrous astrocytes are in white matter; they provide structural and chemical support.

What is the role of microglia in the CNS?

Phagocytes that clear debris and participate in immune responses; involved in neuroinflammation.

What is the role of oligodendrocytes?

Produce and maintain the myelin sheath around CNS axons to speed signaling.

What is the cerebrum’s general function and what are the main cortical layers?

Seat of intelligence; gray matter on the outside (cerebral cortex) and white matter inside (myelinated axons).

What are the major lobes of the cerebrum and their basic functions?

Frontal (higher cognition, decision making, emotion/behavior); Temporal (hearing, language, memory); Parietal (movement coordination); Occipital (visual processing).

What are the superior and inferior colliculi, and what do they do?

Superior colliculi coordinate responses to visual stimuli; Inferior colliculi coordinate responses to auditory stimuli.

What is the substantia nigra and why is it important?

A dopaminergic nucleus important for motor function and reward; central to Parkinson’s disease.

What are the basal ganglia and why are they important?

Deep cerebral nuclei coordinating movement, posture, and aspects of cognition and reward.

What roles do the pons and medulla oblongata play in CNS function?

Pons: movement coordination and modulation of respiration; Medulla oblongata: controls resting and forced breathing and basic autonomic functions.

What is the reticular formation, and what is its relevance?

A network involved in arousal, influencing wakefulness and cardiovascular regulation.

What is the cerebellum mainly responsible for?

Movement and motor control, learning skilled movements, posture, and balance; damage can cause ataxia.

What are the hypothalamus’s key roles?

Autonomic regulation, hormone production, appetite/satiety (ghrelin/leptin), thirst, body temperature, and the master circadian clock (SCN).

What is the thalamus’s function?

Relays and integrates information between the cerebral cortex and other brain regions; important for consciousness/alertness.

What is the limbic system, and which two areas are particularly important for emotion and memory?

Emotion and memory processing; key components include the amygdala (emotions) and hippocampus (memory).

Which neurotransmitter system is central to the motor function and reward pathways and is implicated in Parkinson’s disease?

Dopamine (substantia nigra and ventral tegmental area are key sources).

Which neurotransmitter is the primary inhibitory transmitter in the CNS and is linked to anxiety when deficient?

GABA (gamma-aminobutyric acid).

Which neurotransmitter is the primary excitatory transmitter in the CNS and is crucial for memory and learning?

Glutamate.

Name two monoamine neurotransmitters involved in mood, arousal, and reward.

Dopamine and serotonin (with norepinephrine as another key monoamine).

What are the roles of adrenaline/noradrenaline, and what system are they part of?

Excitatory in the sympathetic nervous system; involved in fight-or-flight responses.

What are the main roles of serotonin in the CNS?

Mood and emotion regulation, appetite, sleep; also a precursor to melatonin.

What substances can diffuse across the blood-brain barrier, and which commonly-encountered substances may cross more readily?

Diffuses: O2, CO2, some hormones, water; cross more readily: alcohol, nicotine, caffeine; many ions and large molecules are restricted.

What are direct costs, direct non-medical costs, and indirect costs in the context of brain disorders?

Direct medical costs (treatment/medication); direct non-medical costs (transport, caregiver time, equipment maintenance, insurance, heating/lighting); indirect costs (economic losses from reduced work and premature mortality).

Which cost category tends to be highest for dementia and why?

Non-medical direct costs, primarily due to extensive caregiver time and home support.

What were UK estimates for mental health costs in 2022, and how do they compare to the NHS budget?

Total cost around £300 billion, largely driven by indirect costs; NHS England budget about £153 billion.

What is the approximate prevalence of mental health problems in England per year and in any given week?

About 25% of people each year; about 1 in 6 people per week.

What is the master clock in the brain, and where is it located?

Suprachiasmatic nucleus (SCN) in the hypothalamus.

What is the glymphatic system, and when will it be discussed in more detail?

A brain-wide waste clearance system; to be discussed in more detail next week.