Biological Bases of Behavior Flashcards

The circadian rhythm is primarily regulated by which brain structure?

Answer: Suprachiasmatic nucleus (SCN)

The suprachiasmatic nucleus in the hypothalamus serves as the body's master clock, synchronizing circadian rhythms to light-dark cycles.

In an EEG, which brain wave pattern is associated with deep, dreamless sleep?

Answer: Delta waves (0.5-4 Hz)

Slow delta waves dominate stages 3 and 4 (N3) of NREM sleep, reflecting synchronized, large-amplitude neural oscillations.

Which pathway is responsible for transmitting fast, sharp pain signals to the brain?

Answer: A-delta fibers via the spinothalamic tract

Myelinated A-delta fibers rapidly transmit sharp, localized pain via the lateral spinothalamic tract to the thalamus and cortex.

Epigenetics refers to changes in gene expression that occur without altering the:

Answer: Underlying DNA sequence

Epigenetic changes like DNA methylation and histone modification alter gene expression without changing the nucleotide sequence of DNA.

Which neurotransmitter system is most directly involved in Alzheimer's disease pathology?

Answer: Cholinergic system

Alzheimer's disease prominently involves degeneration of cholinergic neurons in the basal forebrain, especially the nucleus basalis of Meynert.

The parietal lobe's primary somatosensory cortex contains a distorted body map known as a:

Answer: Homunculus

The cortical homunculus represents body parts proportionally to their sensory cortex area, so hands and lips appear disproportionately large.

Which of the following best describes 'neuroplasticity'?

Answer: The brain's ability to reorganize its structure and function in response to experience

Neuroplasticity encompasses synaptic strengthening, pruning, neurogenesis, and cortical remapping in response to learning and experience.