Biological Basis of Behavior Flashcards

Which brain imaging technique measures blood oxygenation levels to infer neural activity?

Answer: fMRI

fMRI (functional MRI) uses the BOLD signal, which reflects changes in blood oxygenation, to map brain activity.

Myelin sheaths surrounding axons primarily function to:

Answer: Increase the speed of electrical signal transmission

Myelin insulates axons and enables saltatory conduction, dramatically increasing the speed of nerve impulse transmission.

Which division of the autonomic nervous system is most active during a 'fight-or-flight' response?

Answer: Sympathetic division

The sympathetic division activates the fight-or-flight response by increasing heart rate, dilating pupils, and redirecting blood to muscles.

The resting membrane potential of a typical neuron is approximately:

Answer: -70 mV

A neuron at rest maintains a membrane potential of approximately -70 mV due to differential ion concentrations and selective permeability.

Damage to the Broca's area in the left frontal lobe typically results in:

Answer: Difficulty producing fluent speech

Broca's area is critical for speech production; damage causes Broca's aphasia, characterized by slow, effortful, non-fluent speech.

Which neurotransmitter is primarily involved in the reward pathway and is implicated in addiction?

Answer: Dopamine

Dopamine is the primary neurotransmitter in the mesolimbic reward pathway, and dysregulation of this system underlies many addictive behaviors.

The endocrine system communicates with target organs primarily through:

Answer: Chemical messengers transported via the bloodstream

Endocrine glands secrete hormones directly into the bloodstream, which carries them to distant target organs bearing specific receptors.