The Emerging Nervous System

1. The Emerging Nervous System By: Briana and Alexandra

2. The Brain • Neuron: The basic unit in the brain and the rest of the nervous system that specializes in receiving and transmitting information • Cell Body: Center of the cell, contains the basic biological machinery that keeps the neuron alive • Dendrite: receiving end of the neuron

3. The Brain (continued) • Axon: Transmits information to other neurons • Terminal Buttons: located at the end of the axon and release chemicals called neurotransmitters • Neurotransmitters: Messengers that carry information to nearby neurons

4. The Brain (continued) • The cortex consists of left and right halves called hemispheres • Corpus Callosum: Thick bundles of neurons • Frontal Cortex: Personality and ability to make and carry out plans

5. Hemispheres Right • Non verbal tasks • Listening to music • Visual and spatial aspects • Creativity Left • Language processing • Logical thinking such as math • Speech • Reading • Writing

7. The Making of the Brain • Brain weighs three quarters of a pound at birth • Brain weight at birth is 25% of the weigh of the adult brain • Age three- brain has reached 80% of ultimate weight

8. Neurons • Neural Plate: A group of cells that form a flat structure three weeks after conception • At four weeks the neural plate folds to form a tube that than becomes the brain and spinal cord • Neurons begin to produce ten weeks after conception • By 28 weeks almost all neurons are produced • Neurons are formed at 4,000 per second

9. Myelin • In the fourth month of pre-natal development axons begin to acquire myelin • Myelin: The fatty wrap that speeds neural transmission • The process continues through adolescence • The more myelin one has improves their coordination and reaction times

10. Emerging Brain Structures • Months after birth axons and dendrite grow longer and dendrites sprout new limbs • As dendrites increase synapses increase • Synaptic Pruning: Synapses begin to disappear gradually • Brain downsizes, weeding out unnecessary connections between neurons • Usually occurs after time of first birthday

11. Studies on the Brain • Children who suffer brain injuries help to provide information on brain structure and function • Studies of Electrical Activity: metal electrodes are placed on an infants scalp and produce a pattern of brain waves • Functional Magnetic Resonance Imaging: Uses magnetic fields to track the flow of blood in the brain

12. PET SCANS • PET Scans: used sparingly – requires children to be injected with radioactive form of glucose and to lie still for several minutes (can be potentially hazardous)

13. Brain Plasticity • Neuroplasticity: the extent to which brain organization is flexible • Organization of the brain function is thought to be predetermined genetically • The recovery of brain functions are not uncommon and proves the plasticity

14. THE END!