The Brain How is the brain structured? How are the parts connected?

Three major components: –Brainstem –Simplest part of the brain; connects it to the spinal cord –Substructures »Medulla: Controls breathing and heartbeat »Pons: Relays messages between cortex and cerebellum »Midbrain: controls certain reflexes –Cerebellum –Largely responsible for directing controlled motor movements; the part of the brain that sends signals directly to your muscles. –Cerebrum –What we’re really interested –Contains all the brain structures associated with what we thinnk of as “cognition

Several important minor structures Thalamus: Primary sensory switching station; all the senses except olfaction first send signals here. Amygdala: Regulates emotional responses Basal ganglia: Seems to serve as a kind of executive control that mediates between cognition and action (motor movements) Hippocampus: Involved in the formation of memories Corpus callosum: Pathway that the vast majority of signals use to travel from one hemisphere to the other.

Cortical structure Four major lobes: –Occipital: Back of the head; visual processing –Temporal: juts downward from the occipital lobe; auditory processing, including language; involved with memory –Parietal: Top of the brain from the occipital lobe forward to roughly the midpoint; largely responsible for attention and spatial processing; touch –Frontal: The forward half of the brain; higher cognitive functions and motor preparation