Lectures on General Psychology ~ Volume Two

Throughout history human beings have been sleeping. Consider what the Hebrew Testament says. Adam fell asleep and God took a rib and made Eve—it’s been downhill ever since. In the Christian Testament a few thousand years after Adam and Eve the apostles were asleep in the Garden of Gethsemane when Jesus had his crises. So there, it’s proven. People have been sleeping all along.

People have been interested in dreams throughout recorded history. I suppose they have been interested in dreams throughout unrecorded history as well. We don’t know what Adam was dreaming when God took the rib. We like to think it was something positive. The apostles were likely dreaming of divvying up God’s Kingdom among themselves. In the Hebrew Testament Joseph got paid good money to interpret Pharaoh’s dream of the seven fat calves followed by the seven lean calves. In the Christian Testament an angel appeared in the dream of a different Joseph and advised him to get out of town and to take Mary and the Infant Jesus with him.

Consider that we spend one third of our lives asleep. If we live to be thirty, that’s ten full years in the land of Nod. If we live to be ninety, that’s thirty full years. That’s a lifetime spent in Nod. We shouldn’t hold this against Gramps. Sleep is not time wasted, as you will soon hear.

My point in this kind of introduction is the following. People have been asleep and dreaming, but it was only in the 1950s that sleep was studied under controlled scientific conditions. It’s baffling that scientists waited so long to study what happens to the body and to the mind when we pass through customs in Nod—the customs officer on duty is named Murphy. No one knows his personal name.

In 1953 Eugene Aserinsky paid University of Chicago students to sleep in a “sleep laboratory.” This is the opposite of what sometimes happens in this school, where a few students pay us and sleep in class. Many universities and hospitals have “sleep labs” and “sleep clinics” where people with sleep disorders and brain problems can be observed. Aserinsky’s sleep lab was among the first. Quite an original and—after thousands of years—a timely concept.

Aserinsky and his colleagues attached three nonintrusive monitors to the scalps of the students so that the activity of the body could be tracked throughout sleep. The activity going on in the mind was tracked by waking the students up periodically and asking what was on their minds. Were they dreaming or not?

The three machines that monitored the body were the electrooculograph (EOG), the electromylograph (EMG), and the electroencephalograph (EEG). The electrooculograph monitors the movements of the muscles of the eyes. The electromylograph monitors muscle tone—how tight are the muscles of the scalp. And the electroencephalograph monitors the brain wave activity of millions of neurons in the occipital lobes of the brain.

Using a readout of these machines Aserinsky and his colleagues discovered that we have two different kinds of sleep and that we experience a sleep cycle that alternates between the two.

This information was not known to Adam—we like to think God knew it. This information was not known to both Josephs. Sigmund Freud didn’t know it. Carl Gustav Jung didn’t know it. Alfred Adler didn’t know it. No psychologist knew this before 1953. This lack of information didn’t stop psychologists famous and un-famous from writing about dreams. But that’s a different lecture.

The two kinds of sleep are REM sleep—rapid eye movement sleep—and NREM sleep no rapid eye movement sleep. REM sleep is also called paradoxical sleep for a reason I’ll explain shortly. NREM is also called quiet sleep. Unless something bad happens in the meanwhile, I’ll explain that, too. REM and NREM involve different states of the body. And they involve different kinds of dreams.

REM sleep is a unitary, non-differentiated state. Sleepers are either in REM or not in REM. There are no states or levels of REM. NREM is differentiated into four states or levels. These levels are defined by the presence and the amount of delta brain wave activity. When we sleep, we fly delta.

As you recall, neurons give off electrical impulses. Firings of hundreds of thousands of neurons result in identifiable patterns of electrical activities called brain waves. Brain waves are assessed, like all waves, on the basis of frequency and amplitude.

Beta brain waves are found in the alert, awake, thinking and processing brain. This is the state students are in as they listen to the lecture and think about the topic.

Back in the 1960s and 1970s alpha brain waves became notorious when it was discovered that people who regularly meditate show increased levels of alpha brain waves. It was thought alpha brain waves were associated with Nirvana, so a lot of people started pursuing alpha brain waves. Eastern sages achieved alpha brain waves through years devoted to meditation. Practical Americans wanted to enter Nirvana on the quick and easy. Machines were manufactured and offered for sale that monitored brain waves in the same way machines monitored pulse and blood pressure. Scientifically, this endeavor was called biofeedback. Psychologically, it involved applying operant conditioning procedures to increase the rate of alpha brain waves. Religiously, this endeavor was a case of pride—and a case of sloth. People who purchased the machines were separated from their money and remained earthbound on the wheel of karma.

Alpha brain waves occur when we are not focusing on anything or thinking about anything in particular. They might occur when we are drowsing on the D train or when we are sprawled on a beach chair at Coney Island. I don’t doubt they sometimes occur in Prof. Ford’s class.

Delta brain waves are low frequency, high amplitude waves that never occur in the awake brain. They most assuredly do not occur in Prof. Ford’s class, as they occur only in NREM sleep and when a person is in a coma. Please don’t confuse NREM sleep with being in a coma.

There are four stages of NREM sleep. The stages are defined by the presence and amount of delta brain waves. Stage One has no delta waves. Stage Two has less than 20% delta. That is, less than 20% of the total brain wave patterns observed on the EEG are delta waves. Stage Three has 20% – 50% delta. Stage Four has more than 50% delta. That is, more than 50% of the total brain wave patterns observed are delta waves.

The important point to remember is that the greater the percentage of delta brain waves, the deeper the sleep. Stage One is light sleep. Stage Four is deepest sleep. Probably, Adam was in Stage Four when God took the rib.

Overall, NREM sleep accounts for 75% of the total time spent asleep. REM sleep accounts for 25%. Of the four stages of NREM, Stage Two accounts for 50% of the time spent asleep. We are in Stage Two of NREM sleep half the time we are asleep.