External Structures and Function of the Human Brain

Cerebral Hemispheres STRUCTURE -Largest part -Paired divided into left and right hemispheres. -Divided up into 4 main lobes. Cerebral Hemispheres Cerebral cortex is part of the cerebrum, it’s the outer layer. Cerebral cortex is gray matter, while the cerebrum is both gray and white matter. Human cerebral cortex is made up of approximately 10 billion nerve cell bodies and their dendrites whereas the cerebrum has both cell bodies and nerve fibers. FUNCTION -Carries out higher thought processes involved with language, learning, memory, and voluntary body movements

Cerebellum STRUCTURE -Means “little brain” -Smaller structure under the base at the back of the brain  Also divided into two hemispheres Cerebellum FUNCTION -Responsible for balance and coordination 

Brain Stem STRUCTURE -Extends from the base of the brain -Continues into the spinal cord, made up of the pons and medulla oblongata  Brain Stem FUNCTION -Relays signals between the brain and spinal cord - Helps control blood pressure, heart rate, and breathing rate

Lobes of the Brain

Frontal Lobe Frontal STRUCTURE Most uniquely human of all the brain structures. Front of the brain. FUNCTION Conscious thought, behavior, emotion, planning, personality, organizing, problem solving. Frontal

Prefrontal Cortex! (PFC) This brain region has been implicated in planning complex cognitive behavior, personality expression, decision making, and moderating social behavior. Cognitive = knowing Frontal Eye Fields = Broodman’s area (voluntary eye movement)

Parietal Lobe STRUCTURE Middle top of the brain. FUNCTION Integrations of sensory information from primary sensory areas , perception, arithmetic, spelling, manipulation of objects.

Temporal Lobe STRUCTURE Temple region. FUNCTION Senses of smell and sound, as well as processing of complex stimuli like faces and scenes, memory, understanding language.

Occipital Lobe STRUCTURE Extreme back of the brain FUNCTION Sense of sight Occipital Lobe

Internal Structures and Function of the Human Brain

Corpus Callosum STRUCTURE Beneath the cerebrum. About 10 cm long. Largest white matter structure. FUNCTION Allows for communication between the two cerebral hemispheres. About 200 million axons!

Thalamus STRUCTURE Beneath the Corpus Callosum, near the center of the brain. FUNCTION Acts as a gateway/relay of sensory information to the cerebral cortex.

Hypothalamus STRUCTURE Near the base of the cerebrum, below the thalamus. FUNCTION Connects the nervous system to the endocrine system. Communicates and directs the pituitary gland.

Pituitary Gland STRUCTURE A protrusion off of the hypothalamus. FUNCTION Part of the endocrine system. Responsible for regulation of other parts of the endocrine system as well as many of the body’s processes.

Hippocampus STRUCTURE In the temporal lobe, part of the limbic system FUNCTION Plays a role in the formation of new memories based upon experiences. Moves short term memories to long term memories. Hippocampus – Greek Hippos = horse Kampos = sea monster Limbic system  control functions necessary for self preservation and species preservation

Amygdala STRUCTURE In the temporal lobe, part of the limbic system FUNCTION Primary role in processing memory, storage of memories associated with emotions, and decision making Amygdala – Latin and Greek Almond

Amygdala = fear responses & pleasure Hippocampus = turns information into memory