YOUR BRAIN How does your brain work? How can you improve your memory and learning? In what ways can you interfere with your brain’s performance? What’s the best way to nourish your brain?

The Lobes

Inside the Brain

The Brain Your Hands as a Model of your Brain

The Brain Your Hands as a Model of your Brain

Some Brain Facts The brain ways about 3lbs, it is shaped like a walnut and is about the size of a small grapefruit The brain works ceaselessly even when you are asleep The brain represents about 2% of the body’s weight but consumes nearly 20% of the calorie intake! The brain contains both neurons and glial cells. There are about 100 billion neurons in the brain

So how does it work? The brain contains two types of cells, neurons and glial cells. Neurons can vary in length. The longest neuron runs from your toe to the bottom of your spine. Neurons are microscopic but they bundle together to form nerves. Think about how wires are structured...

It’s Electric! Neurons work like electrical wires The brain’s job is to make sense out of incoming messages (sensory neurons) and respond in some way (motor neurons) But how are messages sent?

Axon terminals 4. Myelin sheath Nodes 1. Cell body 3. Axon Nucleus 2. Dendrites 1. Cell body: Contains the nucleus and other cell organelles 2. Dendrites: Short, branched extensions of the cell body *Function: receive stimuli* 3. Axon: long, thin extension of the cell body *Function: sends nerve impulses away from the cell body* (Remember “A” for away!) Structure of a Neuron 4. Myelin sheath: insulating membrane *increases speed of impulse*

A nerve cell has a negative charge when not sending an impulse (“firing”) This charge changes to positive by the movement of ions in and out of the cell This charge change only happens in one spot at a time. Let’s act this out by doing “the wave”!

How do Neurons Communicate? 1. Dendrites receive the signal (action potential) which then travels down to the axon of the first neuron. 2. When the signal reaches the end of the axon, the axon releases chemicals called neurotransmitters. ex. acetylcholine, norepinephrine, dopamine, serotonin 3. Neurotransmitters enter into the space between the 2 neurons, called the synaptic cleft. 4. Neurotransmitters bind to receptors on dendrites of the next neuron thereby passing on the signal.

Vesicle Axon Axon terminal Synaptic cleft Neurotransmitter Receptor Dendrite of adjacent neuron Direction of Impulse Section 35-2 The Synapse = junction between two neurons

The Brain, Spinal cord and Neurons control and coordinate functions throughout the body and responds to internal and external stimuli.

Some Brain FUN Right Brain or Left Brain? nnaire/questionnaire.cgi nnaire/questionnaire.cgi Visual Trickery ex.html ex.html

The "Stroop Effect" Say the Color of the Word and not the Written Word itself.

Reaction Time! How Fast Are You? The Ruler Test Dollar Bill Test dgreen.html dgreen.html exes.htm exes.htm

Reflexes: By-passing the brain Infant reflexes: Palmar grasp reflex, Moro reflex, rooting reflex, walking reflex an involuntary and nearly instantaneous movement in response to a stimulus The reflex arc:

So how does learning work?

Bottom line: We remember things to which we are able to make connections. The more connections we can make the better.

So how can we increase memory and learning? Know your learning style- use images, videos, act things out, put info to music Humor Repetition Mnemonic devices Sense and Meaning Properly nourish your brain Get the right amount of sleep! Practice! Your brain needs training just like the muscles in your body

Try to remember and recall these numbers: How Did I do it? Chunking! And Meaning! And Repetition!

The Teenage Brain and Learning

In what ways can you interfere with your brain’s performance? Not eating well Not getting enough sleep Marijuana, Alcohol, other drugs interrupt nerve impulses at the synapse

What’s the best way to nourish your brain?