The Nervous System

Divisions of the Nervous System Central N.S. (brain and spinal cord) Nervous system Autonomic N.S. (controls self-regulated action of internal organs and glands like The heart and lungs) Somatic N.S. voluntary movements of skeletal muscles) Sympathetic N.S. (arousing) Parasympathetic N.S. (calming) Peripheral N.S. “peripheral” just means on the outside, or NOT central…like your “peripheral vision” ..remember how “soma” means body?

Automatic Actions=Are Simple Reflexes Reflex: a simple, autonomic, inborn response to a sensory stimulus. Spinal cord in charge and brain NOT involved.

The Brain

Regions of the Brain Hindbrain: medulla pons reticular formation cerebellum

The Hindbrain Brainstem: lower base - connects the spinal cord to the brain - oldest part of the brain - responsible for automatic survival functions. Medulla: controls heartbeat and breathing

The Hindbrain Cerebellum: responsible for balance and movement - the “little brain” - attached to the rear of the brainstem. Pons: connects the lower and mid brain regions - regulates brain during sleep and dreaming. Reticular Formation: helps control arousal.

Regions of the Brain Midbrain: contains clusters of nerve cells.

Regions of the Brain Forebrain: most important part of the brain -consists of: thalamus, limbic system, hypothalamus, and cerebral cortex (which contains the lobes of the brain.)

The Forebrain Thalamus: the “sensory switchboard,” or “the relay station.” All auditory (hearing), visual, taste, and touch signals pass through it --> it relays signals to the appropriate part of the brain.

The Forebrain The Limbic System: system plays a major role in controlling emotion and drives (sex, hunger, etc.)

The Limbic System Hippocampus: involved in the formation of memories. Hypothalamus: involved in a variety of drives, such as hunger, thirst, and sex. Pleasure/reward center. Controls the pituitary gland. Pituitary Gland: controlled by the hypothalamus - regulates growth - regulates other glands in the endocrine system. The “master gland.” Amygdala: neural clusters linked to emotions like aggression and fear.

The Limbic System Match the picture with the part of the limbic system that is related to it. amygdala hypothalamus hippocampus pituitary gland

The Limbic System’s “Reward Center”

The Cerebral Cortex The Cerebral Cortex: is the brain’s ultimate control and information processing center; contains all the interconnected neural cells that cover cerebral hemispheres. Contains lobes.

The Lobes Frontal Lobe: involved in speaking and muscle movements along with making plans and judgments. Includes the motor cortex: controls voluntary movements. Parietal Lobe: includes the somatosensory cortex which allows you to register and process body sensations (sense of touch).

Frontal Lobe and Phineus Gage How did Gage’s accident affect him?

The Lobes Occipital Lobe: includes the visual areas involved in seeing. Temporal Lobe: includes the auditory areas which are involved in hearing.

Association Areas: areas of cerebral cortex not involved in motor or sensory processes. Makes up largest portion of cortex which is involved in higher mental functions such as learning, memory, thinking, and speaking.

Cerebral Cortex and Language Aphasia: impairment of language, usually caused by damage to the left hemisphere to the brain either in Broca’s or Wernicke’s area: Broca’s Area: an area of the left frontal lobe that directs the muscle movements involved in speech Broca’s Aphasia Wernicke’s Area: an area of the left temporal lobe involved in language comprehension Wernicke's Aphasia

Brain Reorganization Plasticity: the brain’s capacity for modification as evident in brain reorganization following damage (especially in children) and in experiments on the effects of experience on brain development brain plasticity

Unit 2: Biological Bases of Behavior KEY NAMES Unit 2: Biological Bases of Behavior

key name Paul BROCA 1824-1880 Discovered that a structure in the left frontal lobe controls language production. This structure is now known as “Broca’s”

key name Carl WERNICKE 1848-1905 Discovered that a structure in the left temporal lobe controls language comprehension. This structure is now known as “Wernicke’s”

key name Roger SPERRY 1913-1994 1981 Nobel Prize Winner (medicine) for split-brain research

Michael Gazzaniga Worked under Roger Sperry key name Michael Gazzaniga 1939-Present Worked under Roger Sperry made important advances in our understanding of functional lateralization in the brain and how the cerebral hemispheres communicate with one another

The Divided Brain Corpus Callosum: large bundle of neural fibers that allows the two sides of the brain to communicate. Carries messages between the two hemispheres. Cutting it leads to split brains. L

Split Brain Illustrates Left Brain Used For Language and Right Used For Spatial and Non-Linguistic Functions

Right and Left Brain Functions Cerebral dominance refers to these tendencies for each brain hemisphere to exert control over different functions, such as language (left) or perception of spatial relationships (right). Split Brain Movie

Specialization of the Cerebral Hemispheres Left Hemisphere Right Hemisphere Spontaneous speaking and writing Repetitive but not spontaneous speaking Responses to complex commands Responses to simple commands Word recognition Facial recognition Memory for words and numbers Memory for shapes and music Sequences of movements Spatial interpretation Emotional responsiveness Feelings of anxiety Positive emotion Negative emotion

The Body’s Other Communication Network (Slower) The Endocrine System: the body’s “slow” chemical communication system; secretes hormones into bloodstream.

Endocrine System Components Hormones: cousins of neurotransmitters; chemical messengers, mostly those manufactured by the endocrine glands, that are produced in one tissue and affect another. Adrenal Glands: endocrine glands above the kidneys that secrete the hormones epinephrine (adrenaline) and norepinephrine (noradrenaline), which help to arouse the body in times of stress.