The Backster Effect

Instructor: Brenda Steadham

Brenda has worked with K-12 students in life science, chemistry, and language arts. She holds a master's degree in Biological Sciences.

In this lesson, learn about Cleve Backster's history with the polygraph and his experiments with plants, resulting in what he claimed to be 'plant perception', or what's better known as the 'Backster Effect'.

Truth or Lie?

Are plants capable of emotions? Are they capable of extrasensory perception? Most of us assume that no, plants are unfeeling and certainly not psychic. One man disagreed.

Cleve Backster claimed that his experiments show evidence that plants not only respond to physical and chemical stimuli, but that they are capable of knowing the emotions and thoughts of entities around them. This 'plant perception' became known as the Backster Effect.

Though no other scientists have been able to get the results Backster did, the idea remains intriguing to popular culture. Let's find out more about Backster and his hypothesis.

Who is Cleve Backster?

In the 1960's, Cleve Backster was a pioneer in the art of interrogation, or suspect questioning, for the United State's Central Intelligence Agency (CIA). During Backster's employment there, he and other researchers founded the CIA's first polygraph unit.

The polygraph, also known as a lie detector, is a machine that uses electrodes to monitor changes in an individual's respiratory rate, blood pressure, and galvanic skin response. When telling a lie, it is common for the autonomic nervous system to go into the fight-or-flight mode. The liar's blood pressure and heart rate increase, and they tend to sweat, a galvanic skin response. The machine uses the data gathered to calculate statistical data; the calculated data is converted into graph tracings.

Polygraph session
lie dectection

A Little Experiment

In the mid-1960's, Cleve Backster began pondering alternative uses for the polygraph. One day, when watering the Dracaena plant in his office, an alternative use of the polygraph came to mind. Backster was curious to see if the galvanic skin response electrodes could monitor the movement of water from roots to leaves.

As water moves through the plant, it causes change in the electrical resistance--meaning that as water travels, it causes variations to occur in the positive (+) and negative (-) charges. Backster, based on his current knowledge, expected a decrease in resistance, indicated by an upward line in the polygraph.

The expected change did not occur. After about a minute into the experiment, the plant began exhibiting polygraph tracings resembling those of a human.

History of Happy and Not-So-Happy Plants

Since the late 1800's, scientists have investigated plants' responses to sound, pain, and affection. Experimental psychologist Dr. Gustav Theodor Fechner in the mid 1800s and biophysicist Sir Jagadish Chandra Bose in the early 1900s, postulated that, despite a lack of a brain-like structure, plants have a rudimentary nervous system which enables emotion-style responses. Fechner's and Bose's experimental findings ranged from plants growing away from the direction of continuous, harsh sounds, to plants physically withdrawing from painful stimuli.

These results and other paranormal findings of experimenters since are common subjects of heated debate. The mainstream scientific community dismisses the idea of plant emotionality.

However, Cleve Backster did not doubt the possible existence of paranormal plant emotionality. And he questioned if his polygraph tracings could detect changes, akin to a human's emotional response, in a plant's emotional state.

Psychic Plants

A threat to one's own well-being (or to that of a loved one) can cause significant changes in human polygraph tracings. Under this principle, Backster continued his research into the emotionality of plants. Backster again attached a galvanic skin response electrode to the leaf a Dracaena plant.

Then he chose an adjacent leaf, and dipped it into a cup of hot coffee. There were no significant changes in the polygraph tracings. Baffled, and while still running the experiment, Backster began thinking up other ideas that might illicit a response. He thought about burning the adjacent leaf with a lit match.

As stated by Backster, at that moment the tracings of the polygraph had significant spikes. The plant's tracing changes were comparable to that of a human in distress.

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