Neurons, Brain Chemistry, and Neurotransmission

Biomedical Technology II

Unit 4

Lesson 2

Objectives

• Understand the hierarchal organization of the brain, neuron and synapse

• Understand the sequence of event involved in communication at the synapse

• Understand the synaptic transmission involves neurotransmitters that may be either excitatory or inhibitory

The Brain

• Approximately 3 lbs• Contains billions of cells

– Nerve cells (neurons)– Glial cells (glia)

Neuron

• Basic signaling unit

• 100,000,000,000 = 1011

• Interaction between neurons – Think– Move– Maintain homeostasis– Feel emotions

Activity : Anatomy of a Neuron

• Cell body• Dendrites

• Axon

Neurons Interact with Other Neurons Through Synapses

The Synapse (The connection between)

• Presynaptic neuron – The neuron whose axon forms the synapse

with the dendrite of another neuron

– Sends out information

• Postsynaptic neuron– The neuron whose dendrite forms a synapse

with the axon of the presynaptic neuron

– Receives information

The Reward System

• Ventral Tegmental Area (VTA)

• Nucleus accumbens

• Frontal region of cerebral cortex

Neurons Use Electrical and Chemical Signals to Transmit Information

• Neurons use electrical impulse (action potential) to relay information from one part of a neuron to another

• Neuron coverts the electrical signal to a chemical signal (neurotransmitter)

• Target neuron then converts the message back to an electrical impulse to continue the process

Activity: How Do Neurons Communicate?

Before we begin….

What is the purpose of a synapse?

How do neurons regulate body functions, behaviors, and emotions?

How neurotransmission works….

Recording the Activity of a Neuron

Neurotransmitters

• Excitatory • Inhibitory

Activity: Neurotransmitter Actions

• Analyze the effects of different neurotransmitters on the activity of a neuron

• Answer the questions on worksheet 2.7

Activity: One Neuron Signals Another

• Complete worksheet 2.8B

• We will do Case “A” together