Understanding the Brain: Structure and Connectivity

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

3. 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

4. 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.

6. 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