Anatomy of Nervous Anatomy of Nervous SystemSystem

Objectives: Objectives: Outline the organization of nervous system Outline the organization of nervous system Compare the structure and function of neurons Compare the structure and function of neurons

and neuroglia. and neuroglia. Describe the 3 layers of meningens around the Describe the 3 layers of meningens around the

central nervous system central nervous system Locate and identify the major regions of the brain Locate and identify the major regions of the brain

and describe their function.and describe their function. Describe the structure and functions of the spinal Describe the structure and functions of the spinal

cord. cord. Distinguish between the sympathetic and Distinguish between the sympathetic and

parasympathetic division. parasympathetic division.

The Nervous System The Nervous System The major controlling, regulatory, and The major controlling, regulatory, and

communicating system in the body. communicating system in the body. The center of mental activity : thought, The center of mental activity : thought,

learning and memory.learning and memory. With endocrine system is responsible for With endocrine system is responsible for

regulating and maintaining regulating and maintaining homeostasis. homeostasis.

Keep us in touch with external and Keep us in touch with external and internal environment. internal environment.

Functions : - sensory functionsFunctions : - sensory functions - integrative functions- integrative functions - motor functions - motor functions

Functions of Nervous systemFunctions of Nervous systemExternal (stimuli : temp, light,sound)External (stimuli : temp, light,sound)

Internal (body : receptors detect variations in pressure, Internal (body : receptors detect variations in pressure, PH,CO2concentration, & level of elit)-------SENSORY INPUTPH,CO2concentration, & level of elit)-------SENSORY INPUT

Electrical signals (nerve impulses) Electrical signals (nerve impulses) Brain (create sensations)Brain (create sensations) Produce thoughts ---decision is made based on input Produce thoughts ---decision is made based on input

sensory---sensory---INTEGRATIONINTEGRATION

Respon to muscles and glandsRespon to muscles and glands ----- ----- MOTOR OUTPUTMOTOR OUTPUT

The Brain

Meninges of The Central Nervous SystemMeninges of The Central Nervous System

(CSF and blood vessels)

(Dural sinus : venous return)

(Thin and delicate layer)

Lobes and Functional Areas of the Lobes and Functional Areas of the CerebrumCerebrum

The Neuron The Neuron

Transmit impulses to neuron cell body (AFFERENT PROCESS)

(EFFERENT PROCESS)

(white matter)

(regeneration of nerves fibers)

The NeuronThe Neuron Conducting nerve impulses.Conducting nerve impulses. They are highly specialized and They are highly specialized and

amitotic amitotic (lack of centrioles).(lack of centrioles). Each neuron has 3 basic parts :Each neuron has 3 basic parts :

- Cell body- Cell body- One or more dendrites- One or more dendrites- A single axon- A single axon

The NeurogliaThe Neuroglia Neuroglia cells do not conduct nerve Neuroglia cells do not conduct nerve

impulses, BUT, impulses, BUT, Support, nourish and protect the Support, nourish and protect the

neurons. neurons. They are far more numerous than They are far more numerous than

neurons.neurons. Capable of mitosis. Capable of mitosis.

CerebrumCerebrum Cerebral cortex ---Sensory areas Cerebral cortex ---Sensory areas

interpret sensory impulses, motor interpret sensory impulses, motor areas control muscular areas control muscular movement and association areas movement and association areas function in emotional and function in emotional and intellectual process.intellectual process.

Basal ganglia (gray matter) Basal ganglia (gray matter) coordinates gross, automatic coordinates gross, automatic muscle movements and regulate muscle movements and regulate muscle tone.muscle tone.

Limbic system consists of Limbic system consists of scattered but interconnected scattered but interconnected regions of gray matter in cerebral regions of gray matter in cerebral hemispheres and diencephalon--- hemispheres and diencephalon--- involved in memory and emotions involved in memory and emotions :sadness,happiness,anger & fear :sadness,happiness,anger & fear (EMOTIONAL BRAIN)(EMOTIONAL BRAIN)

Medulla OblongataMedulla Oblongata Relays motor and sensory Relays motor and sensory

impulses between other impulses between other parts of the brain and the parts of the brain and the spinal cord. spinal cord.

Vital centers regulate Vital centers regulate heartbeat, breathing heartbeat, breathing together with pons, and together with pons, and blood vessel diameter. blood vessel diameter.

Other centers coordinate Other centers coordinate swallowing, vomiting, swallowing, vomiting, coughing, sneezing, and coughing, sneezing, and hiccuping. hiccuping.

Contains nuclei of origin Contains nuclei of origin for cranial nerves VIII, IX, for cranial nerves VIII, IX, X, XI, and XII. X, XI, and XII.

PonsPons Relay impulses from Relay impulses from

one side of the one side of the cerebellum to the cerebellum to the other and between the other and between the medulla and midbrain. medulla and midbrain.

Contain nuclei of origin Contain nuclei of origin for cranial nerves V, for cranial nerves V, VI, VII, and VIII. VI, VII, and VIII.

Pneumotaxic area and Pneumotaxic area and apneuistic area, apneuistic area, together with the together with the medulla, help control medulla, help control breathing. breathing.

Midbrain Midbrain Relays motor impulses from the cerebral Relays motor impulses from the cerebral

cortex to the pons and sensory impulses cortex to the pons and sensory impulses from the spinal cord to the thalamus. from the spinal cord to the thalamus.

Superior colliculi coordinate movements of Superior colliculi coordinate movements of the eyeballs in response to visual and the eyeballs in response to visual and other stimuli other stimuli (visual reflex center).(visual reflex center).

Inferior colliculi coordinates movements of Inferior colliculi coordinates movements of the head and trunk in response to auditory the head and trunk in response to auditory stimulistimuli.(auditory reflex center).(auditory reflex center)

Contains nuclei of origin for cranial nerves Contains nuclei of origin for cranial nerves III and IV. III and IV.

CerebellumCerebellum Compares intended movements with Compares intended movements with

what is actually happening to smooth what is actually happening to smooth and coordinate complex, skilled and coordinate complex, skilled movements. movements.

Regulates posture and balance.Regulates posture and balance.

HypothalamusHypothalamus Controls and integrates activities of the Controls and integrates activities of the

autonomic nervous system and pituitary autonomic nervous system and pituitary gland---gland---maintain homeostasis maintain homeostasis

Regulates emotional and behavioral Regulates emotional and behavioral patterns and circadian rhythms. patterns and circadian rhythms.

Controls body temperature and regulates Controls body temperature and regulates eating and drinking behavior.eating and drinking behavior.

Helps maintain the walking state and Helps maintain the walking state and establish pattern of sleep.establish pattern of sleep.

Thalamus Thalamus Relays all sensory input to the cerebral Relays all sensory input to the cerebral

cortex.cortex. Provides crude perception of touch, Provides crude perception of touch,

pressure, pain, and temperature.pressure, pain, and temperature. Includes nuclei involved in voluntary Includes nuclei involved in voluntary

motor actions and arousal; anterior motor actions and arousal; anterior nucleus functions in emotions and nucleus functions in emotions and memory. memory.

Also function in cognitive and Also function in cognitive and awareness. awareness.

Organization of The Nervous SystemOrganization of The Nervous System

(voluntary)

Skeletal muscles

(involuntary)

Cardiac muscle smooth muscle skin

Spinal NervesSpinal Nerves

Autonomic Nervous System (ANS)Autonomic Nervous System (ANS)

Is a visceral efferent system (it sends Is a visceral efferent system (it sends motor impulses to visceral organs).motor impulses to visceral organs).

It functions automatically and continuously It functions automatically and continuously without conscious effort ----- to innervate without conscious effort ----- to innervate smooth muscle, cardiac muscle and smooth muscle, cardiac muscle and glands. glands.

It concerns with HR, RR, BP, and It concerns with HR, RR, BP, and temperature to maintain homeostasis. temperature to maintain homeostasis.

It has 2 parts : sympathetic and It has 2 parts : sympathetic and parasympathetic division parasympathetic division

Structure and Function of ANSStructure and Function of ANS