Brain, Body, and Behavior Learning Goals Overview / Overview

Facts about the human brain Looks like compressed macaroni Uses about 20 percent of our oxygen Eats up most of the sugar we take in Operates on 20 watts of electrical power 100 billion nerve cells

Cerebral Cortex Definition The outermost layer of the brain, controls high level mental processes such as thought. About the size of a bath towel if untwisted and spread out.

Which hemisphere controls movements of the right side of the body Which hemisphere controls movements of the right side of the body? Left side? What is the depression between the hemispheres called? What connects the two hemispheres? Each hemisphere controls the opposite side of the body! The divider (depression) is known as a fissure The two hemispheres are connected by a bundle of fibers known as the corpus callosum – oddly enough you can survive even if the two hemispheres don’t talk!

Severed Corpus Callosum http://www.youtube.com/watch?feature=player_em bedded&v=zx53Zj7EKQE

What are the functions of each of the lobes of the brain? Frontal Lobe – is responsible for a number of very complex functions, including the ability to “see” ourselves, remember things (memory) and tasks dealing with intelligence. – oh and the motor strip is also located in this lobe. Parietal lobe – contains the sensory strip (works closely with the Frontal lobe) Occipital lobe – contains the visual cortex, and processing centers Temporal lobe – contains major centers for hearing, and speech. (one note – language is handled by all four lobes to some extent.)

What are the functions of the sensory and motor strips What are the functions of the sensory and motor strips? In which lobe is each located? Sensory – handles information dealing with our major senses, including pain. (location – Partial lobe) Motor – handles our body movements – the book talks about surgeons stimulating this strip to stimulate various parts of the body – (frontal lobe)

Prefrontal (Frontal Lobe), Frontal Association & Size of Frontal Prefrontal – helps us re experience our lives (memories) along with strategies or plans of action. Frontal Association Area – packed with neurons helps us interpret what is going on and tell us what to do and what to feel. Also seems to be the core of personality. Size = intelligence level

Phineas P. Gage The Tale of Mr. Gage – in three min….

What does it mean to be dominant in one hemisphere? It simply means that either the right or left hemisphere is preferred and controls the majority of actions performed. How does this impact people who are left handed vs right?

Corpus Callosum These fibers (as stated earlier) help the two hemispheres communicate. Sometimes they have to be cut to stop electoral disturbances in the brain (seizures) For a patient with a severed callosum, they might be able to see objects but not be able to say what they are….this is one possibility.

Tasks of left and right hemispheres Speech Language Logic Writing Spatial reasoning Art Music Emotions

Difference between cerebral cortex and the lower brain? Cortex = bark (like on a tree) Part of the brain that is common to animals and humans that regulates basic functions such as breathing

Main Parts of the Lower Brain Thalamus – relay station, handles incoming and outgoing messages (super important) Hypothalamus – regulates basic needs (hunger, thirst) Limbic system – emotions and memory Amygdala – emotion…especially agression Hippocampus – memories Cerebellum – coordinates body movements for balance and accuracy RAS – Reticular Activating System - alertness

Neuron

Neuron… continued Axon – carrries messages away from the cell to the dendrites on another neuron Dendrites – receive information from the axon of other neurons Synapse – gap between two neurons Neurotransmitters- chemicals that “jump” the gap , to help send messages (there are all many types) Vesicles – contain neurotransmitters located at the ends of Axons

Neurotransmitters Acetylcholine – regulates basic bodily processes such as movement Dopamine – also involved in the control of bodily movement A shortage of dopamine plays a central role in Parkinson’s disease Endorphins – neurotransmitters that relieve pain and increase our sense of well-being

Central Nervous System Brain Spinal Cord The Spinal Cord – functions as an automatic “brain” in its own right and as a relay station for impulses to and from the higher brain. Reflexes – automatic behavior of the body involving movement that is activated through the spinal cord without the use of the higher brain. More on reflexes…

Peripheral Nervous System Simply stated is all of the nerves outside the brain and spinal cord

Somatic vs Autonomic Sympathetic vs Parasympathetic Somatic: contains sensory and motor nerves Autonomic: regulates breathing, heart rate, digestion and so on. Sympathetic: Part of the Autonomic system that energizes and prepares for emergencies Parasympathetic: works in opposition to the sympathetic to help calm us down.

Hormones Part of the Endocrine System – work in conjunction with the Central Nervous System Glands Pituitary (Master G – controls/activates all other glands) Thyroid – connected to metabolism Adrenal – chemicals that cause excitement in order to prepare the body for an emergency

Hormones Gonads – sex glands that make the sperm or eggs used for reproduction Androgen – the male sex hormone Estrogen – the female sex hormone Both males and females have each, but for the male there is more (androgen) and female more (estrogen) What might happen if the glands described in the last two slides were too active or not active enough?

Phrenology Phrenology - is a pseudoscience primarily focused on measurements of the human skull, based on the concept that the brain is the organ of the mind, and that certain brain areas have localized, specific functions or modules. The distinguishing feature of phrenology is the idea that the sizes of brain areas were meaningful and could be inferred by examining the skull of an individual. 

How does science / technology learn about the brain? EEG – uses electrical firing of the brain to graph brain waves. Electrodes are attached to the head. I’ve had this done during sleep apnea testing. PET scan – glucose (sugar) is injected to the bloodstream, a machine scans the brain and takes pictures of the levels of radioactivity produced. MRI – a machine that takes images of the brain’s activity – has become extremely effective, however, people with claustrophobia may not like the technique. FMRI - The hidden power of smiling