Thinking About Psychology: The Science of Mind and Behavior Charles T. Blair-Broeker Randal M. Ernst

The Brain Module 08

Lower-Level Brain Structures: The Brainstem Module 8: The Brain

Brainstem The oldest part of the brain Is responsible for automatic survival functions Located where the spinal cord swells and the brain just begins

Medulla The base of the brainstem Controls life-supporting functions like heartbeat and breathing Damage to this area can lead to death.

Reticular Formation A nerve network extending up and down the spinal cord into the brain Controls an organism’s level of alertness Damage to this area can cause a coma.

7 Brain Stem

Lower-Level Brain Structures: The Thalamus Module 8: The Brain

Thalamus Sits atop the brainstem The brain’s sensory switchboard -- directs messages to the sensory receiving areas in the cortex (except smell) Thalamus is Greek for “inner chamber.”

10 The Thalamus.

Lower-Level Brain Structures: The Cerebellum Module 8: The Brain

Cerebellum Latin for the “little brain” Located in the rear of the brain Helps coordinate voluntary movements and balance If damaged, the person could perform basic movements but would lose fine coordination skills.

Lower-Level Brain Structures: The Limbic System Module 8: The Brain

Limbic System A ring of structures around the thalamus; at the border of the brainstem and cerebral cortex Helps regulate memory, aggression, fear, hunger, and thirst Includes the hypothalamus, hippocampus, and amygdala

Hypothalamus Located directly under the front of the thalamus Regulates eating, drinking, body temperature, and the fight or flight reactions to stress Plays a role in emotions, pleasure, and sexual function

Hippocampus Wraps around the back of the thalamus Plays a role in processing new memories for permanent storage Looks something like a seahorse –Hippo is Greek for “horse.”

Amygdala Two almond shaped structures Controls emotional responses such as fear and anger

The Cerebral Cortex Module 8: The Brain

Cerebral Cortex The body’s ultimate control and information processing center Covers the brain’s lower level structures Contains an estimated 30 billion nerve cells Divided into four lobes

Corpus Callosum The large band of neural fibers that connects the two brain hemispheres and carries messages between them Is sometimes cut to prevent seizures

Longitudinal Fissure The crevice that divides the brain into two halves or hemispheres This and other fissures in the brain create major divisions in the brain called lobes

Frontal Lobes The portion of the cerebral cortex lying just behind the forehead Is involved in making plans and judgments

Parietal Lobes Regions available for general processing, including mathematical reasoning Designated as the association lobes Behind the frontal lobes

Occipital Lobe The primary visual processing area Located in the back of the head

Temporal Lobes Includes the auditory cortex where sound information is processed Located roughly above the ears

37 PHINEAS Gage CASE STUDYGage

Motor Cortex Area at the rear of the frontal lobes Controls voluntary movement Different parts of the cortex control different parts of the body. The motor cortex in the left hemisphere controls the right side of the body and vice versa.

Somatosensory Cortex Located in the front of the parietal lobes Registers and processes body senses Soma is Greek for “body.”

pencil sensing activity