Neural Quest: Test Your Brainpower on the Nervous System

Dive into 20 brainy questions on neurons, reflexes, and the brain—challenge your knowledge and spark curiosity about how we think and feel.

  1. Which brain structure is primarily responsible for forming new declarative memories?
    1. Thalamus
    2. Amygdala
    3. Cerebellum
    4. Hippocampus
  2. What type of neuron conducts impulses from sensory receptors toward the central nervous system?
    1. Motor neuron
    2. Efferent neuron
    3. Interneuron
    4. Afferent neuron
  3. Which ion's rapid influx primarily causes the rising phase of an action potential in neurons?
    1. Calcium
    2. Potassium
    3. Sodium
    4. Chloride
  4. Which glial cell produces myelin in the peripheral nervous system?
    1. Astrocyte
    2. Oligodendrocyte
    3. Schwann cell
    4. Microglia
  5. Damage to Broca's area most directly impairs which ability?
    1. Balance control
    2. Visual recognition
    3. Speech production
    4. Long‑term memory
  6. Which neurotransmitter is most closely associated with reward and motor control and is deficient in Parkinson's disease?
    1. Dopamine
    2. Serotonin
    3. GABA
    4. Acetylcholine
  7. What reflex uses only a sensory and motor neuron without interneurons in the spinal cord?
    1. Monosynaptic reflex
    2. Polysynaptic reflex
    3. Conditioned reflex
    4. Autonomic reflex

Answers and explanations

  1. Question: Which brain structure is primarily responsible for forming new declarative memories?
    Answer: Hippocampus
    Explanation: The hippocampus consolidates short‑term experiences into long‑term declarative memories; damage impairs new memory formation. Fun fact: London taxi drivers show enlarged hippocampi linked to spatial memory.
  2. Question: What type of neuron conducts impulses from sensory receptors toward the central nervous system?
    Answer: Afferent neuron
    Explanation: Afferent (sensory) neurons transmit external and internal sensory information to the CNS; they differ from efferent motor neurons. Fun fact: some afferent neurons have cell bodies in dorsal root ganglia.
  3. Question: Which ion's rapid influx primarily causes the rising phase of an action potential in neurons?
    Answer: Sodium
    Explanation: Voltage‑gated sodium channels open first, allowing Na+ influx that depolarizes the membrane and triggers the spike. Fun fact: local anesthetics block these channels to prevent pain signals.
  4. Question: Which glial cell produces myelin in the peripheral nervous system?
    Answer: Schwann cell
    Explanation: Schwann cells wrap individual PNS axons with myelin, enabling saltatory conduction; oligodendrocytes myelinate multiple CNS axons instead. Fun fact: Schwann cells also aid axon regeneration after injury.
  5. Question: Damage to Broca's area most directly impairs which ability?
    Answer: Speech production
    Explanation: Broca's area is essential for planning and producing fluent speech; lesions cause nonfluent aphasia with preserved comprehension. Fun fact: Broca's area is usually left‑lateralized in right‑handed people.
  6. Question: Which neurotransmitter is most closely associated with reward and motor control and is deficient in Parkinson's disease?
    Answer: Dopamine
    Explanation: Dopamine pathways regulate reward, motivation, and basal ganglia motor circuits; loss of dopaminergic neurons causes Parkinsonian symptoms. Fun fact: dopamine also shapes learning via prediction errors.
  7. Question: What reflex uses only a sensory and motor neuron without interneurons in the spinal cord?
    Answer: Monosynaptic reflex
    Explanation: Monosynaptic reflexes, like the knee‑jerk, involve a single synapse between sensory and motor neurons for rapid responses. Fun fact: their latency is one of the shortest reflex times in the body.