Central nervous system

RECAP Flip back to Nervous System Chart Central Nervous System Sensory input and motor output Brain and Spinal Cord Integrate the information to battle anything that would threaten homeostasis (balance)

Parts of the brain to Know O Brain Stem O Diencephalon O Cerebrum O Cerebellum

From the surface inward O Cranial bones and vertebrae O Membranes = meninges (in the brain) O Dura Matter O Arachnoid Membrane O Pia Matter

Meninges: Dura Matter O Outer layer O Strong white and fibrous O Inner periosteum of the cranial bones as well O Contains blood vessels and nerves

Meninges: Arachnoid O Delicate O Cobweb like O Between the Dura and Pia Matter

Meninges: Pia Matter O Innermost layer O Transparent O Adheres to the brain and spinal cord O Contains many blood vessels and nerves

Meninges Recap O Brain Tumor Removal Brain Tumor Removal

CSF: Cerebrospinal Fluid O Cushion of fluid around the brain and spinal cord O Monitored by the brain for changes in internal environment O Found in subarachnoid space, canals, and cavities of brain and spinal cord

CSF: formation O Separation of fluid from blood in the choroid plexuses (networks of capillaries that project from the pia matter into the ventricles) O Ependymal cells (type of glia) release fluid into the fluid spaces O Circulates through the ventricles, central canal, and subarachnoid space O Then absorbed back into blood

O CSF circulation CSF circulation

o Cerebrum o Cerebellum o Brain Stem The Brain

CEREBELLUM o Balance and coordination

CEREBRUM - wrinkly large part of the brain, largest area in humans, higher mental function

Brain Stem - regulates visceral functions (autonomic system)

Figure 13.4

1. Cerebral Hemispheres: left and right side separated by the Corpus Callosum: connects the two hemispheres

The Cerebral Hemispheres Figure 13.7b, c

Corpus callosum

Convolutions of the Brain - the wrinkles and grooves of the cerebrum Fissures = deep groove Sulcus = shallow groove Gyrus = bump

4. Fissures – separate lobes Longitudinal fissure - separate right and left sides

Transverse Fissure - separates cerebrum from cerebellum

Lateral Fissure separates the temporal lobe from the Frontal and Parietal lobes

Lobes of the Brain 5. Frontal – reasoning, thinking, language 6. Parietal – touch, pain, relation of body parts (somatosensory) 7. Temporal Lobe – hearing 8. Occipital – vision

Figure 13.7a LOBES OF THE BRAIN (CEREBRUM) Sulcus = groove Gyrus = raised bump Fissure = deep groove

9. Cerebral Cortex - thin layer of gray matter that is the outermost portion of cerebrum (the part with all the wrinkles)

Functional and Structural Areas of the Cerebral Cortex Figure 13.11a

Fluid filled cavities, contain CSF 10.VENTRICLES OF THE BRAIN

11. Cerebrospinal Fluid (CSF) - fluid that protects and supports brain Figure 13.27b

Hypothalamus - hormones, heart rate, blood pressure, body temp, hunger Thalamus - relay station Diencephalon has 2 parts.....

BRAIN STEM Consists of three parts: MIDBRAIN PONS MEDULLA OBLONGATA

Figure 13.4 BRAIN STEM

Midbrain – visual reflexes, eye movements Pons - relay sensory information Medulla – heart, respiration, blood pressure Cerebellum - balance, coordination

Pituitary Gland The "master gland" of the endocrine system. It controls hormones.

Optic Tract / Chiasma - optic nerves cross over each other

FUNCTIONAL REGIONS A. MOTOR AREAS B. SENSORY AREAS C. ASSOCIATION

Motor Areas - controls voluntary movements - the right side of the brain generally controls the left side of the body -also has Broca's Area (speech)

Sensory Area - involved in feelings and sensations (visual, auditory, smell, touch, taste)

Two Point Test Subject ASubject B Back of hand Palm of hand Inside Arm Cheek Chin Back of Neck Tip of Thumb Tip of index finger Ankle

Association Areas - higher levels of thinking, interpreting and analyzing information

Two Point Test Reflection O What part of the body is the most sensitive O Do males and females differ? O Explain what a “threshold stimulus” is.

HIPPOCAMPUS Memory is controlled by the HIPPOCAMPUS The hippocampus plays a major role in memories.

The LIMBIC SYSTEM The LIMBIC SYSTEM plays a role in EMOTION also includes olfactory lobes - memory, emotion, and smell are linked. Crayola's are created today with the same scent because it reminds people of their happy times in childhood. Why is the brain formed so that smell and emotions are tied together?

O Because pheromones are tied to emotions and behavior, so they need the link.

MEMORY We used to classify memory as being long- term or short-term. The new classification is four memory systems that process information for storage and retrieval: Types of Memory: Short vs Long Term

Erase Memories? O Article O Would you do it? O Why?

How important are your memories? If you were involved in a traumatic event, such as a rape or a terrorist attack, would you take a pill that would make it so that you did not remember the event? 1/05/27/drug-metyrapone-to- erase-bad-memories/26532.html

Involved in remembering personal experiences, such as a phone conversation you had yesterday or the movie you watched last week. Challenge: Do you remember the first Harry Potter movie? What was the story? How many details do you remember? Episodic Memory

Semantic Memory Manages the storage and retrieval of general knowledge of facts, such as the number of days in a year or the colors in a rainbow. Naming objects is also semantic memory. Semantic Memory Tasks 1. What do you call this thing? 2. Where do Kangaroos live? 3. What actor played Bella in Twilight?

Procedural Memory Allows us to learn activities and skills that will then be performed automatically with little or no conscious thought. Examples are riding a bicycle or driving a car. Challenge: 1. Can you make a teacup with a length of string? 2. Do you know how to use a can opener?

Working Memory Provides temporary storage and manipulation of the information necessary for such complex cognitive tasks as language comprehension, learning, and reasoning. Another Memory Game

Spinal Cord

passes down the vertebral canal, has 31 segments (each with a pair of spinal nerves) Cervical enlargement = supplies nerves to upper limbs (neck) Lumbar enlargement = supplies nerves to the lower limbs (lower back)

Tracts of the Spinal Cord

Functions of Spinal Cord O Conductions to and from the brain O Ascending (sensory) tracts conduct information up the cord to the brain O Descending (motor) tracts conduct information down the cord from the brain

Spinal Cord Structure

What am I looking at? O Anterior Fissure O Posterior Sulcus O Gray Matter “H” in the middle O White Matter surrounds O Nerve root on both sides

Nerve Root O Dorsal (posterior) = Sensory O Ventral (anterior) = Motor O Each Level has a R and L

Spinal Nerve O A single mixed nerve on each sided of the spinal cord where dorsal and ventral join together

Spinal Nerves 8 pairs of cervical nerves (C1 - C8) 12 pairs of thoracic nerves (T1- T12) 5 pairs of lumbar nerves (L1-L5) 5 pairs of sacral nerves (S1-S5) 1 pair of coccygeal nerves (Co) 31 Total

*Spinal cord ends at the level between the 1 st and 2 nd lumbar vertebrae *The lumbar, sacral, coccygeal nerves descend from the end of the cord – CAUDA EQUINA (horse’s tail)

Cauda Equina

PLEXUSES Main portions of the spinal nerves combine to form complex networks called PLEXUSES

Dermatomes O A section of the skin supplied with sensory fibers O “Skin Section”

Myotomes O Skeletal muscle or group of muscles that receive motor axons from a specific spinal nerve. O Can be overlap O Several muscles innervated by multiple nerves O Several nerves innervating a single muscle