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The nervous system develops from embryonic tissue

called the ectoderm. The first sign of the developing nervous

system is the neural plate that can be seen at about the 16th

day of development. Over the next few days, a "trench" is

formed in the neural plate - this creates a neural groove. By

the 21st day (week 3) of development, a neural tube is

formed when the edges of the neural groove meet. The front

part of the neural tubes goes on to develop into the brain

and the rest of the neural tube develops into the spinal cord.

Neural crest cells become the peripheral nervous system.

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DDEEVVEELLOOPPMMEENNTT The cells of the nervous system connect with one another in trillions of remarkably specific patterns that

form and change over the course of an organism’s life. These connections develop among various types of

neurons, a process that begins in the embryo. Knowing how the brain is put together is essential for

understanding its ability to reorganize in response to external influences or injury.

By fourth weeks, major regions of the human brain

can be recognized in primitive form, including the forebrain,

midbrain, hindbrain, and optic vesicle (from which the eye

develops). Irregular ridges, or convolutions, are clearly seen

by six months.

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International Brain Bee Syllabus 2012

Department of Neurosciences, Universiti Sains Malaysia ®

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Brain Bee@USM 2013 edited from

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Dendrites

Cell body

Nucleus

Axon

Myelin sheath

Direction of impulse

Axon terminals

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These specialised cells are the information-processing units of the brain responsible for receiving and transmitting information. Each part of the neuron plays a role in the communication of information throughout the body. They come in many shapes and sizes enabling them to conduct specialized functions such as storing memories and controlling our muscles.

Information from one neuron flows to another neuron across a small gap called a synapse. At the synapse, electrical signals are translated into chemical signals (called neurotransmitter) in order to cross the gap. Neurotransmitter is released from the axon terminal after an action potential has reached the synapse. The neurotransmitter then crosses the synaptic gap to reach the receptor site of the other cell or neuron. Then, in a process known as reuptake, the neurotransmitter attaches to the receptor site and is reabsorbed by the neuron.

The neurons are composed of cell

bodies, dendrites and axons. Dendrites

are tree-like extensions at the

beginning of a neuron. They receive

information from other neurons and

transmit electrical stimulation to the

cell body. Cell body contains nucleus

and cytoplasm, and is the cell’s control

center. The electrically excitable axon

extends from the cell body and often

gives rise to many smaller branches

before ending at nerve terminals. The

larger the axon, the faster it transmits

information. Some axons have an outer

layer called myelin sheath that speeds

the messages along the pathway. These

myelinated axons transmit information

much faster than other neurons.



http://psychology.about.com/od/aindex/g/actionpot.htm

http://psychology.about.com/od/aindex/g/actionpot.htm

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Cerebral cortex is the largest and most advanced part of the brain. It is divided into two hemispheres, right and left. The right being more concerned with the artistic and creative ability, while the left is more concerned with analytical aspects. Each half of cerebral cortex is divided into four lobes:

Frontal Lobe

Reasoning Problem-solving Personality and emotion Motor control Memory

Parietal Lobe

Pain processing Touch sensation Cognition Movement and orientation Speech

Temporal Lobe

Auditory and sensation Language recognition Emotion Long-term memory Speech

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Located right underneath cerebral cortex and below the brainstem, cerebellum is the second biggest part of the brain (1/8 the size of cerebral cortex). The cerebellum is similar to the cerebral cortex in some ways, where it is divided into hemispheres and has a cortex that surrounds these hemispheres.

The cerebellum’s main job is to control balance, movement, and coordination (how your muscles work together). Because of your cerebellum, you can stand upright, keep your balance, and move around. Cerebellum is also said to be involved in learning.

Occipital Lobe

Visual sensation and processing

Frontal Parietal

Occipital Temporal

Cerebellum

Brain Stem

Major Internal Structures

The forebrain is credited with the highest intellectual functions (i.e. thinking, planning, and problem-solving). The hippocampus is involved in memory. The thalamus serves as a relay station for almost all the information coming into the brain. Neurons in the hypothalamus serve as relay stations for internal regulatory systems by monitoring information coming in from the autonomic nervous system and commanding the body through those nerves and the pituitary gland.

On the upper surface of the midbrain are two pairs of small hills, colliculi, collections of cells that relay specific sensory information from sense organs to the brain.

The hindbrain consists of the pons and medulla oblongata, which help control respiration and heart rhythms, and the cerebellum, which helps control movement as well as cognitive processes.

Thalamus

Forebrain

Medulla

Oblongata

Cerebellum

Pons

Hindbrain

Midbrain Hypothalamus

Hippocampus

Amygdala



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0 5 10 15 20 25 30 35 40 45 30 35 40 45 50 55 60 65 70

Parkinson Schizophrenia

Autism

Huntington’s disease

Major depression / bipolar disorder

Multiple sclerosis

ADHD

Alzheimer’s

YEAR

Tourette

Syndrome



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PET

MRI

MRS

fMRI

MEG

Optical Imaging

Techniques

Imaging techniques Alteration of

chromosome structure (e.g:

Huntington's Disease)

Alteration of chromosome number (e.g: Down Syndrom)

Gene diagnostics

PET

MRI

MRS

fMRI Optical Imaging

Techniques

MEG



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NEURAL DISORDERS

CLINICAL FEATURES EPIDEMIOLOGY/ PREVALENCE

CAUSES/FACTORS TREATMENT

Addiction

Alcohol Club drugs Marijuana Nicotine Opiates Psychostimulants

Alzheimer’s Disease

Earliest stages Progress

symptoms Final stages

Amyotrophic lateral Sclerosis (Lou Gehrig’s Disease)

Paralysis Respiratory

failure

Anxiety Disorders

Obsessive-

compulsive disorder

Panic disorder Phobias Social anxiety

disorder Generalized

anxiety disorder Post-traumatic

stress disorder



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Attention Deficit Hyperactivity Disorder

Excessively

inattentive, hyperactive or impulsive behaviours

Autism

Communication

difficulties Absent, delayed

or abnormal language

Impaired social skills

Narrow, obsessive interests or repetitive behaviours

Common symptoms: Mental retardation, seizures and behavioral abnormalities

Bipolar Disorder

Deep depression

and manic highs with a return to relatively normal functioning in between

Have increased risk of suicide

Brain Tumors

Seizures Headache Vomiting Visual

disturbances Impaired mental

functioning



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Down Syndrome

Mild to moderate

intellectual disabilities

Low muscle tone Upward slant to

the eyes A flat facial

profile Enlarged tongue Increased risk of

congenital heart defects

Respiratory problems

Digestive tract obstruction

Dyslexia

Learning

disability (reading)

Huntington’s Disease

Earliest stages:

Involuntary jerking movements of the limbs, torso and facial muscles

Progress symptoms

Final stages

Major Depression

Sadnesso Hopelessness Pessimism Loss of interest in

life Reduced

emotional well-being



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Multiple Sclerosis

Numbness Fatigue Blurred vision Clumsiness Slurred speech Weakness Loss of

coordination Pain & tremors Loss of bladder

control Memory and

cognitive problems

Depression

Neurological AIDS

Affected immune

and nervous system

Dementia Mental problems

Neurological Trauma

Head or spinal

cord injuries Edema or

swelling Ischema

Pain

Chronic or

debilitating headache

Pain arthritis Neuropathic pain

Parkinson’s Disease

Slowness of

movement Muscular rigidity Tremor Postural

instability



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Schizophrenia

Disturbances in

thinking, emotional reaction and social behavior

Chronic illness and personality change

Delusions Hallucinations Thought disorder

Seizures and Epilepsy

Two types:

Generalized epilepsy and partial epilepsy

Occurrence of unprovoked seizures

Stroke

Paralysis (one

side or whole of the body)

Loss of speech

Tourette Syndrome

Motor and vocal

tics (repetitive, involuntary movements or utterances that rapid, sudden and persist for more than one year



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DRUG

Trophic factors

Engineered antibodies

Small molecules and RNAs

Cell and gene

therapy



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Major Concerns Personal responsibility and punishment

Diagnosis, treatment and enhancement

Social behavior

Prediction

Informed consent in research

Effective and ethical science communication and commercial enterprise

For further reading, please download Brain Facts: A Primer on the Brain and Nervous System at

http://www.sfn.org/index.aspx?pagename=brainfacts



http://www.sfn.org/index.aspx?pagename=brainfacts

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