BAI GIANG VE NAO BO (BRAIN)

Gray matter and white matter• Gray matter 40% of CNS: cell bodies, dendrites, axon terminals- synaptic communication and neural integration • White matter 60% of CNS:bundles of axons

Central nervous system , along with

animal’s physiology and behaviors

Cùng với

Common structural organization of all vertebrate brains

:

• Three main regions:

Hill.Wyse.Anderson Animal physiology.2e.Sinauer Associates, 2008

The structure of human brain

Gray matter and white matter

• Gray matter (40% of CNS): cell bodies, dendrites, axon terminals- synaptic

communication and neural integration

• White matter (60% of CNS):bundles of axons connecting regions of gray

matter: association fibers,

projection fibers, commissural fibers

C.L Standfield.2011 Principles of Human Physiology, 4thedition

Bó

Nhô ra, lồi ra Chỗ nối

Cranial nerves

Cerebral cortex – functional organization

• Outermost portion of the cerebrum with high convolutions of thin gray matter layer (1-4 mm thick)

•Six functionally distinct layers of cortex

•Gyrus (plr Gyri), sulcus (sulci)

•Central sulcus and lateral sulcus

• Each cerebral hemisphere: 4 lobes: frontal, parietal, occipital, temporal

C.L Standfield.2011 Principles of Human Physiology, 4thedition

Vỏ

Ngoài cùng

Nếp, cuộn

Bán cầu não

Thùy trán Thùy đỉnh

Thùy chẩm

Thùy thái dương

Rãnh bên

The cerebral cortex is divided into

Certain brain functions are dominant

on one side of the brain relative to the other: the left side of the brain controls movements of the right side of the body and vice versa

sự lệch hóa

Primary motor cortex and primary somatosensory cortex are topoghraphically organized: the motor and sensory homunculi

Hill.Wyse.Anderson Animal physiology.2e.Sinauer Associates, 2008

attention

• Information from cerebellum and basal ganglia ->thalamus->motor cortex: feedback in controlling

movementVùng đồi thị

• is a part of the limbic system-> affects emotions and

behaviors in response to emotions

• has direct and indirect inputs to the autonomic nervous system

• has the suprachiasmatic nucleus generating and regulating circadian rhythm

Vùng dưới đồi

Thỏa mãn Đói Khát

Biên, viền

Limbic system

• is a collection of closely associated cortical regions, subcortical nuclei and tracts in the forebrain functioning in

motivation, memory, and emotions

• is involved in basic drives :

– amyglada : aggression and fear

– hippocampus: learning and memory

Bieân, vieàn

• Fine Movement Coordination

• Balance and Equilibrium

• Muscle Tone

Brain stem

• Location for nuclei of 10 from 12 cranial nerves

• Involves involuntary control of posture

• regulates basic vital life functions: centers for cardiovascular and respiratory activities

• Involves sleep-wake cycles

Electroencephalogram (EEG)

web.lemoyne.edu/~hevern/psy340/lectures/psy34

The spinal cord

• the portion of CNS surrounded by the vertebral column

• nuclei for 31 pairs of spinal nerves which are arranged segmentally:

– 8 cervical nerves (C1-C8) – 12 thoracic nerves (T1-T12) – 5 lumbar nerves (L1-L5) – 5 sacral nerves (S1-S5) – 1 coccygeal nerve (Co)

• spinal nerves travel to adjacent regions of the body -> sensory regions

in the body’s surface can be mapped out:

dermatomes

• clinicians/physicians can use the map to find the location of damage

to the spinal cord and spinal nerves

Fig 9.7 C.L Standfield.2011 Principles of Human Physiology, 4thedition

Spinal cord gray matter

• forms a butterfly shaped region centering the spinal cord

• is organized into dorsal and ventral regions:

– dorsal horn : site of axon terminals of sensory neurons which have cell bodies in dorsal root ganglia;

– ventral horn : site for cell bodies of motor neuron

• Lateral horns in the gray matter of T1-L2 are the sites preganglionic neurons of the sympathetic nervous system

The white matter of the spinal cord

• consists of tracts connecting different levels of the spinal cord or between the brain and the spinal cord

• ascending and descending tracts generally cross over to the opposite side of its origin : contralateral

pathway

Left side of the brain percieves sensory information from and exerts motor control to the right side of the body, and vice versa

Reflex and components of a reflex arc

C.L Standfield.2011 Principles of Human Physiology, 4thedition

• Reflex is a response

of the body to a stimulus

• Neural pathways for reflexes are reflex arcs

• A reflex arc consists

of 5 components

Classes of reflexes

Stretch reflex

• Knee-jerk reflex/muscle spindle stretch reflex

the human body

• muscle spindle (receptor)-> afferent neuron -> spinal cord-

>efferent neuron->

muscle (Hamstrings) Thoi cơ

C.L Standfield.2011 Principles of Human Physiology, 4thedition

The autonomic nervous system

• controls visceral functions :

smooth muscles, glands (exocrine and some endocrine glands), acid-secreting cells of the stomach, pacemaker region

of the heart, the brown adipose tissue

• autonomous functions are

• has two main divisions:

– Sympathetic Nervous System (SNS)/

thoracolumbar division

– Parasympathetic Nervous System (PSNS)/

Common features of ANS

• Motor pathways of ANS contain 2 neurons communicating through peripheral synapses located in autonomic ganglia:

– Preganglionic neuron

– Postganglinonic neuron

• CNS-> Preganglionic neuron ->Postganglinonic neuron-> effectors

Hill.Wyse.Anderson Animal physiology.2e.Sinauer Associates, 2008

Neurotransmitters and receptors in

the ANS

• Neurotransmitters:

– preganglionic neuron of ANS: acetylcholine (ACh)

−postganglionic neuron of SNS: norepinephrine (NE), epinerphrin (E)

–postganglionic neuron of PSNS: acetylcholine (ACh)

• Receptors:

− for ACh: nicotinic cholinergic receptor, muscarinic cholinergic receptors

−for E, NE: adrenergic receptors

Sympathetic and parasympathetic nervous

- promotes “fight or flight” responses

- Promotes mobilizing body energy

reserves, makes the body ready to face

with stress

- increases heart rate, cardiac output,

blood pressure, blood glucose level,

lung ventilation

- Inhibits activities involving digestion,

urination, defecation, sexual arousal

- promotes “rest and digest” or “feed and bread” activities when the body

- promotes activities involving digestion, urination, defecation, sexual arousal

C.L Standfield.2011 Principles of Human Physiology, 4thedition.

1 Draw a typical neuron and label the main structures, list the

functions of each structure

2 If an anion is located in greater concentration outside the cell

compared to inside, would the equilibrium potential for that

anion be positive, negative or zero? Explain it.

3 Explain ionic basic of an action potential

4 Explain why myelinated axons conduct action potential faster

than unmyelinated axons?

5 Explain why the transmission of action potential in axon is not

bidirectional?

6 Draw a typical chemical synapse, label the main structures, list

the functions of each structure

7 Describe the sequence of events occuring at a chemical

synapse

8 Explain ionic basic of an EPSP

9 Compare and contract the events caused by the binding of

neurotransmitters to ionotropic and metabotropic receptors