All MCAT Social and Behavioral Sciences Resources
Example Questions
Example Question #1 : Pathways And Processed Of Consciousness Altering Drugs
Which area of the brain is most directly associated with an individual's overall level of alertness and arousal?
Lateral geniculate nucleus
Reticular formation
Pons
Substantia nigra
Frontal lobe
Reticular formation
The reticular formation is a set of nuclei located in the brainstem that control an individual's level of alertness through its three columns: the raphe nuclei (helps synthesize serotonin for mood control), magnocellular red nucleus (aids in motor coordination), and parvoreticular cellular nucleus (helps breathing control—specifically exhalation).
The substantia nigra is a group of dopaminergic neurons located in the basal ganglia that synthesize the majority of the dopamine in the brain. The pons relay signals to the cerebellum from lower brain centers, and deals with sleep, reflexes, taste, facial expressions, facial sensation, and posture. It is located above the medulla oblongata, which houses the olivary nuclei that form the reticular formation. The frontal lobe allows for control of attention, tasks associated with short-term memory, planning, and motivation. It is comprised mainly of dopamine-sensitive neurons, which allows for selection of relevant information from the thalamus. Last, the lateral geniculate nucleus is a thalamic relay center for the visual system. It receives sensory information from the retina via the optic nerve and relays it posteriorly to the occipital lobe.
Certified Tutor
Certified Tutor