What are the Neurons building blocks and of nervous system? Brain 1. Neurons 2. Glia: supports
neurons
Neuron: Structure Neuron: Structure
Three basic parts: • Axon terminals 1. Cell body
2. Axon •Synapse
3. Dendrites
Neuron: Function
specialized in
• Receiving
• Transmitting
• Processing information
One way transmission: from dendrites to axon
1 How Neurons Communicate
One way transmission: from dendrites to axon.
1. Electrical
2. Chemical
1. Electrical signals 1 (b) Action potential
• Resting Potential - sudden change in the electrical charge across the neuron’s membrane
- electrical system in equilibrium - all-or-none response (polarization of ions) (threshold)
Synapse How Neurons Communicate? Neurotransmitters 2. Chemical Transmission 2 effects:
1. Excitatory generate action potential in the next neuron 2. Inhibitory
more difficult for the second neuron to fire
2 Damage
Brain 1-2. Medulla & Pons 3 • control heart rate & breathing 3 Main Parts 2 • carry visual & auditory information 1 • respiration • movement 1. Hindbrain • facial expression • sleep 2. Midbrain Damage to Pons:
3. Forebrain Locked-in syndrome
3. Reticular formation I. Hindbrain 4. Cerebellum a) Filters sensory information “little brain” b) Regulate overall arousal in the brain Coordinated motor activity
• If damaged - sleepy or aroused; Damage: poorly coordinated muscle functioning -coma
3 II. Midbrain III. Forebrain Involve in 1. Thalamus - Vision - Receive -Hearing - Filter - Organize - Pain-relieving function -Transmit - Some motor movements information from our senses (except smell) to other parts of the brain
2. Hypothalamus
• Eating & drinking (amount of nutrition stored in cells)
• Aggression
Regulates: Sexual behavior
3. Limbic system b) Amygdala a) Hippocampus: organizes memory functioning emotions
damage - inability to store • stimulation – elicit aggression & rage new information • damage – reduces aggression
4 4. Cerebral Cortex Corpus Callosum
2 hemispheres Corpus callosum
A set of axons connecting the two hemispheres
Split-Brain Phenomenon 4 regions or lobes
1. Occipital Lobe 2. Parietal Lobe
Vision a) spatial awareness “neglect” phenomenon Damage:
• “Blindness” • Face-blindness • Inability to recognize colors • Motion-blindness
5 2. Parietal Lobe 3. Frontal lobe
a) Primary Motor Cortex Sensory Cortex
Processes
information
about pain, touch, temperature
4. Temporal Lobe 3. Frontal lobe -hearing b) “executive system “ - some aspects of vision
- Planing Damage to the L hemisphere - Decision making inability to understand spoken words
- Forming concepts Damage to the R hemisphere - Processing & storing information recognize speech, but not organizations of sound (melody, tune) -Self-regulation
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