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VIRTUAL LAB BRAIN WAVES. Instructor Terry Wiseth. Start Lab. Monitor. WHAT DO I NEED TO HAND IN FOR THIS LAB? Data Table for Brain Waves 2) Answers to Questions. DATA ACQUISITION UNIT. Stimulator Outputs. Recording Inputs. +. 1. Power. -. 2. Stop Recording. Start Recording.
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VIRTUAL LAB BRAIN WAVES Instructor Terry Wiseth Start Lab
Monitor • WHAT DO I NEED TO HAND IN FOR THIS LAB? • Data Table for Brain Waves • 2) Answers to Questions DATAACQUISITIONUNIT StimulatorOutputs RecordingInputs + 1 Power - 2 Stop Recording Start Recording EEGSensor Click here to view a printable DATA TABLE for Brain Waves Click here to view a printable list of QUESTIONS for Brain Waves Click here to begin collecting data for this lab Click here to view the INTRODUCTION Next Previous Skip Intro End Lab
Monitor Click on the Blackboard to view a larger blackboard DATAACQUISITIONUNIT StimulatorOutputs RecordingInputs + 1 Power - 2 Stop Recording Start Recording EEGSensor 30 Next Previous Skip Intro End Lab
Monitor The presence of electrical current in the brain was discovered by an English physician, Richard Caton, in 1875. It was not until 1924 that Hans Berger, a German neurologist, used his ordinary radio equipment to amplify the brain's electrical activity so that he could record it on graph paper. Berger noticed that rhythmic changes (brain waves) varied with the individual's state of consciousness. The various regions of the brain do not emit the same brain wave frequency simultaneously. DATAACQUISITIONUNIT StimulatorOutputs RecordingInputs + 1 Power - 2 Stop Recording Start Recording EEGSensor Next Previous Skip Intro End Lab
Monitor An EEG electrode placed on the scalp would pick up many waves with different characteristics. This has presented a great deal of difficulty to researchers trying to interpret the large amount of data they receive from even one EEG recording. Brain waves have been categorized into four basic groups: Alpha, Beta, Theta, and Delta waves. Although none of these waves is ever emitted alone, the state of consciousness of the individual may make one frequency more pronouncedthan the others. DATAACQUISITIONUNIT StimulatorOutputs RecordingInputs + 1 Power - 2 Stop Recording Start Recording EEGSensor Next Previous Skip Intro End Lab
Monitor You may have seen doctors in hospitals or on television taking EEG readings of the natural and ongoing electrical activity of a person's brain. This activity is produced by all of us all the time and it varies according to what kind of activity we are engaged in. It can be recorded by sensors that are gently placed on the head. A geodesic sensor net, which looks a bit like a hairnet with lots of little sponges attached to it can be used to acquire this electrical activity. The net contains 64 sensors, which are all sewn together. DATAACQUISITIONUNIT StimulatorOutputs RecordingInputs + 1 Power - 2 Stop Recording Start Recording EEGSensor Next Previous Skip Intro End Lab
Monitor Brain waves are obtained from a special analysis of EEG. These brain waves show us the brain's response to a particular stimulus or external event, such as a picture or sound. Brain activity before, during, and after a stimulus presentation is recorded. This allows us to observe where, when, and how the brain responds to a given stimulus. DATAACQUISITIONUNIT StimulatorOutputs RecordingInputs + 1 Power - 2 Stop Recording Start Recording EEGSensor Next Previous Skip Intro End Lab
Monitor Any physiological investigation of the brain can emphasize and expose only a very minute portion of its activity. Higher brain functions, such as consciousness and logical reasoning, are extremely difficult to investigate. DATAACQUISITIONUNIT StimulatorOutputs RecordingInputs + 1 Power - 2 Stop Recording Start Recording EEGSensor Next Previous Skip Intro End Lab
Monitor It is obviously much easier to do experiments on the brain’s input-output functions, some of which can be detected with appropriate recording equipment. Still, the ability to record brain activity does not necessarily guarantee an understanding of the brain. Certain characteristics of brain waves are known. They have a frequency of 1 to 30 hertz (Hz) or cycles per second, a dominant rhythm of 10 Hz and an average amplitude (voltage) of 20 to 100 microvolts (uV). DATAACQUISITIONUNIT StimulatorOutputs RecordingInputs + 1 Power - 2 Stop Recording Start Recording EEGSensor Next Previous Skip Intro End Lab
Monitor Frequency is the number of times a wave repeats itself within a second. It can be compared to the frequencies that you tune into on your radio. If any of these frequencies are deficient, excessive, or difficult to access, our mental performance can suffer. Amplitude represents the power of electrical impulses generated by brain. A wave can be of high or low amplitude (voltage) and high or lowfrequency (regularity). DATAACQUISITIONUNIT StimulatorOutputs RecordingInputs + 1 Power - 2 Stop Recording Start Recording EEGSensor Next Previous Skip Intro End Lab
Monitor The first of the brain waves to be described by scientists were the Alpha Waves (or alpha rhythm). Alpha waves have an average frequency range of 8 to 13 Hz and are produced when the individual is in a relaxed state with the eyes closed. Alpha block, suppression of the alpha rhythm, occurs if the eyes are opened or if the individual begins to concentrate on some mental problem or visual stimulus. Under these conditions, the waves decrease in amplitude but increase in frequency. Under conditions of fright or excitement, the frequency increases still more. DATAACQUISITIONUNIT StimulatorOutputs RecordingInputs + 1 Power - 2 Stop Recording Start Recording EEGSensor Next Previous Skip Intro End Lab
Monitor Beta Waves, closely related to alpha waves, are faster, 14 to 30 Hz and have a lower amplitude. They are typical of the attentive or alert state. Very large (high-amplitude) waves with a frequency of less than 4 Hz that are seen in deep sleep are Delta Waves. DATAACQUISITIONUNIT StimulatorOutputs RecordingInputs + 1 Power - 2 Stop Recording Start Recording EEGSensor Next Previous Skip Intro End Lab
Monitor Theta Waves are large, abnormally contoured waves with a frequency of 4 to 7 Hz. Although theta waves are normal in children, they represent emotional problems or some sort of neural imbalance in adults. Gamma Waves, are brain waves larger than 30 Hz. These waves predominate during periods of times we are “thinking”. DATAACQUISITIONUNIT StimulatorOutputs RecordingInputs + 1 Power - 2 Stop Recording Start Recording EEGSensor Next Previous Skip Intro End Lab
Monitor DATAACQUISITIONUNIT StimulatorOutputs RecordingInputs + 1 Power - 2 Stop Recording Start Recording EEGSensor Click here to learn more about Delta Waves Click here to learn more about Theta Waves Click here to learn more about Alpha Waves Click here to learn more about Beta Waves Click here to learn more about Gamma Waves Next Previous Skip Intro End Lab
Monitor In normal adults who are awake, the EEG shows mostly Alpha waves and Beta waves. In abnormal adults the EEG shows sudden bursts of electrical activity (spikes) or sudden slowing of brain waves. These abnormal discharges may be caused by a brain tumor, infection, injury, stroke, or epilepsy. When a person has epilepsy, the location and exact pattern of the abnormal brain waves may help determine what type of epilepsy or seizures the person has. Keep in mind that in many people with epilepsy, the EEG may appear completely normal between seizures. DATAACQUISITIONUNIT StimulatorOutputs RecordingInputs + 1 Power - 2 Stop Recording Start Recording EEGSensor Next Previous Skip Intro End Lab
Monitor A disorder affecting the entire brain, such as drug intoxication, certain infections, or metabolic disorders that upset the chemical balance in the body, including the brain, may produce abnormal brain waves. In these abnormalities the EEG shows delta waves or an excess of theta waves in adults who are awake. These results may indicate brain injury. DATAACQUISITIONUNIT StimulatorOutputs RecordingInputs + 1 Power - 2 Stop Recording Start Recording EEGSensor Next Previous Skip Intro End Lab
Monitor • If the EEG shows no electrical activity in the brain (a "flat" or "straight-line"). This indicates that brain function has stopped, which is usually caused by lack of oxygen or blood flow inside the brain. In some cases, severe drug-induced sedation can produce a flat EEG. This state also can be seen in status epilepticus after a significant amount of medication is given to control the seizure. A person who has a flat EEG for more than 6 hours is usually considered brain dead, unless heavily sedated with medications. DATAACQUISITIONUNIT StimulatorOutputs RecordingInputs + 1 Power - 2 Stop Recording Start Recording EEGSensor Next Previous Skip Intro End Lab
Monitor Brain waves change with age, sensory stimuli, brain pathology or disease. Glucose deprivation, oxygen poisoning and sedatives all interfere with the rhythmic activity of brain output by disturbing the metabolism of the neurons. Sleeping individuals and patients in a coma have EEGs that are slower (or lower frequency) than the alpha rhythm of normal adults. Fright, epileptic seizures, and various types of drug intoxication are associated with faster brain activity. Impairment of brain function is indicated by neuronal activity that is either too fast or too slow. DATAACQUISITIONUNIT StimulatorOutputs RecordingInputs + 1 Power - 2 Stop Recording Start Recording EEGSensor Next Previous Skip Intro End Lab
Monitor We are now ready to begin the lab. You will be assigned a subject who will perform various mental activities for you. You will be using a device which will be able to record the brain waves of your subject while they are performing the mental tasks. You will need to record the mental activities attempted and sketch and identify the brain waves which are recorded. You will alsoneed to answer questionson your data collected. DATAACQUISITIONUNIT StimulatorOutputs RecordingInputs + 1 Power - 2 Stop Recording Start Recording EEGSensor Next Previous Skip Intro End Lab
Monitor • WHAT DO I NEED TO HAND IN FOR THIS LAB? • Data Table for Brain Waves • 2) Answers to Questions DATAACQUISITIONUNIT StimulatorOutputs RecordingInputs + 1 Power - 2 Stop Recording Start Recording EEGSensor Click here to view a printable DATA TABLE for Brain Waves Click here to view a printable list of QUESTIONS for Brain Waves Click here to begin collecting data for this lab Click here to view the INTRODUCTION again Next Previous Skip Intro End Lab
Monitor When your subject is seated and you have instructed him to sit quietly and read, click on NEXT Click on your subject to seat your subject and start the procedure DATAACQUISITIONUNIT StimulatorOutputs RecordingInputs + 1 Power - 2 Stop Recording Start Recording EEGSensor 0 Next Previous End Lab
Monitor Now click on the NEXT button at the bottom of the page Next connect the EEG sensor box to the data acquisition unit. Click on the blue cord leading from the EEG sensor DATAACQUISITIONUNIT StimulatorOutputs RecordingInputs + 1 Power - 2 Stop Recording Start Recording EEGSensor 0 Next Previous End Lab
Monitor Now click on the RED power button on the Data Acquisition Unit to start collecting data Next click on the NEURAL HAT lying on the desk to place on your subjects head DATAACQUISITIONUNIT StimulatorOutputs RecordingInputs + 1 Power - 2 Stop Recording Start Recording EEGSensor 0 Next Previous End Lab
Click on the green START RECORDING button and collect data for 30 sec When data has been collected for 30 seconds you can click on the monitor to zoom in on the data image DATAACQUISITIONUNIT StimulatorOutputs RecordingInputs Monitor + 1 Power - 2 Stop Recording Start Recording EEGSensor 15 20 10 5 30 25 0 Next Previous End Lab
Monitor Sketch the brain waves shown here in the data table in the row provided for the appropriate activity of your subject DATAACQUISITIONUNIT StimulatorOutputs RecordingInputs Monitor + 1 Power - 2 Stop Recording Start Recording EEGSensor Click here to learn more about this type of brain wave Next Previous Click here to View the Data Table End Lab
For the next part of the lab we will collect data when our subject has their eyes closed and is relaxed. Click on NEXT DATAACQUISITIONUNIT StimulatorOutputs RecordingInputs Monitor + 1 Power - 2 Stop Recording Start Recording EEGSensor 15 20 10 5 30 25 0 Next Previous End Lab
Instruct your subject to close their eyes and relax. You can do this by clicking on the subject Next click on the RED power button on the Data Acquisition Unit Now Click on NEXT at the bottom of the page DATAACQUISITIONUNIT StimulatorOutputs RecordingInputs Monitor + 1 Power - 2 Stop Recording Start Recording EEGSensor 0 5 10 15 20 25 30 Next Previous End Lab
Click on the green START RECORDING button and collect data for 30 sec When data has been collected for 30 seconds you can click on the monitor to zoom in on the data image DATAACQUISITIONUNIT StimulatorOutputs RecordingInputs Monitor + 1 Power - 2 Stop Recording Start Recording EEGSensor 15 20 10 5 30 25 0 Next Previous End Lab
Monitor Sketch the brain waves shown here in the data table in the row provided for the appropriate activity of your subject DATAACQUISITIONUNIT StimulatorOutputs RecordingInputs Monitor + 1 Power - 2 Stop Recording Start Recording EEGSensor Click here to learn more about this type of brain wave Next Previous Click here to View the Data Table End Lab
For the next part of the lab we will collect data when our subject is given a very complex problem. Click on NEXT DATAACQUISITIONUNIT StimulatorOutputs RecordingInputs Monitor + 1 Power - 2 Stop Recording Start Recording EEGSensor 15 20 10 5 30 25 0 Next Previous End Lab
Recite this math problem to your subject. You can do this by clicking on the subject Next click on the RED power button on the Data Acquisition Unit Now Click on NEXT at the bottom of the page 5 + 6 X 45 – 35 + 22 X 31 DATAACQUISITIONUNIT StimulatorOutputs RecordingInputs Monitor + 1 Power - 2 Stop Recording Start Recording EEGSensor 0 5 10 15 20 25 30 Next Previous End Lab
Click on the green START RECORDING button and collect data for 30 sec When data has been collected for 30 seconds you can click on the monitor to zoom in on the data image DATAACQUISITIONUNIT StimulatorOutputs RecordingInputs Monitor + 1 Power - 2 Stop Recording Start Recording EEGSensor 15 20 10 5 30 25 0 Next Previous End Lab
Monitor Sketch the brain waves shown here in the data table in the row provided for the appropriate activity of your subject DATAACQUISITIONUNIT StimulatorOutputs RecordingInputs Monitor + 1 Power - 2 Stop Recording Start Recording EEGSensor Click here to learn more about this type of brain wave Next Previous Click here to View the Data Table End Lab
For the next part of the lab we will collect data when our subject is given an emotionally distressing note. Clickon NEXT DATAACQUISITIONUNIT StimulatorOutputs RecordingInputs Monitor + 1 Power - 2 Stop Recording Start Recording EEGSensor 15 20 10 5 30 25 0 Next Previous End Lab
BADNEWS Give your subject a distressing note. You can do this by clicking on the subject Next click on the RED power button on the Data Acquisition Unit Now Click on NEXT at the bottom of the page DATAACQUISITIONUNIT StimulatorOutputs RecordingInputs Monitor + 1 Power - 2 Stop Recording Start Recording EEGSensor 5 10 15 20 25 30 0 Next Previous End Lab
Click on the green START RECORDING button and collect data for 30 sec When data has been collected for 30 seconds you can click on the monitor to zoom in on the data image DATAACQUISITIONUNIT StimulatorOutputs RecordingInputs Monitor + 1 Power - 2 Stop Recording Start Recording EEGSensor 0 5 10 15 20 25 30 BADNEWS Next Previous End Lab
Monitor Sketch the brain waves shown here in the data table in the row provided for the appropriate activity of your subject DATAACQUISITIONUNIT StimulatorOutputs RecordingInputs Monitor + 1 Power - 2 Stop Recording Start Recording EEGSensor Click here to learn more about this type of brain wave Next Previous Click here to View the Data Table End Lab
Monitor • This is the end of the BRAIN WAVE LAB. Be sure that you include in your lab report the following listed items. • 1) Brain Wave Data Table • 2) Answers to Questions DATAACQUISITIONUNIT StimulatorOutputs RecordingInputs + 1 Power - 2 Stop Recording Start Recording EEGSensor Click here to view a printable DATA TABLE for Brain Waves Click here to view a printable list of QUESTIONS for Brain Waves Click here if you would like to review the INTRODUCTION If you are finished with this lab you can click here to END the lab Click here to start the DATA COLLECTION again Next Previous End Lab
Click here to Return Click for a printable DATA TABLE
Click for a printable DATA TABLE Click here to Return
Click here to Return Click for a printable DATA TABLE
Click here to Return Click for a printable DATA TABLE
QUESTIONS FOR BRAIN WAVE LAB 1) Describe the difference between amplitude and frequency in regards to brain waves. 2) Describe the brain waves of an individual who is “brain dead”. 3) List the dominant brain wave we would find in individuals performing the following activities: a) Sleeping b) Under Stress c) Relaxing with eyes open d) Concentrating Click here to Return Click for a printable QUESTIONS list
DELTA WAVES • The lowest frequencies are DELTA • These are less than 4 Hz • Occur in deep sleep and in some abnormal processes • Delta waves increase during sleep in the normal adult • As people move from lighter to deeper stages of sleep, the occurrence of alpha waves diminishes and is gradually replaced by the lower frequency theta and then delta rhythms Previous Page Next Page (more about Delta Waves) Return to Intro Theta Waves Beta Waves Alpha Waves Delta Waves Gamma Waves
DELTA WAVES • Delta waves may increase during difficult mental activities requiring concentration • We increase Delta waves in order to decrease our awareness of the physical world • We also access information in our unconscious mind through Delta • Peak performers decrease Delta waves when high focus and peak performance are required Previous Page Next Page (more about Delta Waves) Return to Intro Theta Waves Beta Waves Alpha Waves Delta Waves Gamma Waves
DELTA WAVES • However, most individuals diagnosed with Attention Deficit Disorder, naturally increase rather than decrease Delta activity when trying to focus • The inappropriate Delta response often severely restricts the ability to focus and maintain attention • It is as if the brain is locked into a perpetual drowsy state Previous Page Next Page (more about Delta Waves) Return to Intro Theta Waves Beta Waves Alpha Waves Delta Waves Gamma Waves
DELTA WAVES • It is the dominant rhythm in infants up to one year of age and it is present in stages 3 and 4 of sleep • Another way to look at Delta is to imagine you are driving in a car and you shift into 1st gear....you're not going to get anywhere very fast • So Delta would represent 1st gear Previous Page Return to Intro Theta Waves Beta Waves Alpha Waves Delta Waves Gamma Waves
THETA WAVES • As calmness and relaxation deepen into drowsiness, the brain shifts to slower, more powerfully rhythmic waves with a frequency of about 4 -7 Hz • low-frequency EEG patterns that increase during sleep in the normal adult • Theta has been associated with access to unconscious material, creative inspiration and deep meditation Previous Page Next Page (more about Theta Waves) Return to Intro Theta Waves Beta Waves Alpha Waves Delta Waves Gamma Waves