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Two Wars Hence

Marcus Licinius Crassus was 62 years old. He was the richest man in Rome, decorated with honors, and a member of the secret ruling Triumvirate with Julius Caesar and Pompey Magnus. But it wasn't enough for him.

In renewing his political alliance with Caesar and Pompey, they dealt out assignments and power to the members of the Triumvirate. Crassus would go southeast to fight and conquer the Parthian Empire.

Crassus was the classical expansionist. But he made the fatal error; he did not take his next opponent seriously.

As he marched his legions to fight the Parthians, he was bragging that after Parthia he would keep going -- maybe all the way to India.

He was ill-prepared for the Parthian mounted horse archers, some of the most dangerous in the ancient world. Even then, Roman allied and Crassus's officers alike recommended plans that would have saved Crassus's force if he hadn't blundered forwards.

Class 6: Brain Waves

On Briana Brownlow's Brain and Behavior Lab Blog

It's the middle of the night and you are laying in bed, fast asleep, far off somewhere in dream land. But even as you sleep soundly, your mind is wide awake. Nerve impulses are sent and received to and from neurons, these impulses are the brain's way of passing messages. The nerve impulses create electrical activity in the brain. This activity is present even in sleep. How do we know? Electrical activity of the brain can be detected and recorded by placing electrodes on the scalp. The electrodes detect the activity of the brain region just under it. This technique is called electroencephalography or EEG. The EEG picks up on four periodic rhythms of brain waves, alpha, beta, delta and theta. Each rhythm is associated with various states. Alpha rhythm is prominent when someone is awake, but relaxed with their eyes closed. Beta rhythms occur when someone is alert, exerting mental effort, or attending to external stimuli. However, beta rhythms also occur during REM sleep, which is when the stage in sleep where the eyes are rapidly moving. Delta and theta rhythms increase during sleep. In the study conducted in lab, an EEG was used to record the changes in the brains electrical activity and these specific rhythms. When the subjects eyes were closed the frequency of each EEG rhythms were lower than when they opened their eyes and when they re-closed their eyes. For instance, the alpha rhythm was 2.27 when their eyes were closed, 2.77 when there eyes were opened, and then 2.78 when there eyes were re-closed. Furthermore, when the subject did a mental math problem with their eyes closed the standard deviation of the EEG went from the baseline of 3.93 to 4.04; and following hyperventilation with their eyes still closed it went from 3.93 to 5.33; and when the subject kept their eyes open it went from 3.93 to 6.37. Thus, even though their eyes were closed the task they were being asked to do (mental math or hyperventilate) increased the electrical activity of the brain and having their eyes open increased that activity even further. The EEG was able to capture that by detecting the changes in the brain waves. The changes in each rhythm also reflected these changes in brain activity. Even in a relaxed state (eyes closed), what the mind is focusing on can have a large impact on increasing the activity in the brain.

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