The phenomenon that is known as street lamp interference, or SLI, is possibly a psychic event that is just beginning to be recognized and studied. Like most phenomena of this type, the evidence is almost exclusively anecdotal. 

Typically, a person who has this effect on streetlights -- known as a SLIder -- finds that the light switches on or off when he or she walks or drives beneath it. Obviously, this could happen occasionally by chance with a faulty streetlight (you've probably noticed that it's happened to you once in a while), but SLIders claim that it happens to them on a regular basis. It doesn't happen every time with every streetlight, but it occurs often enough to make these people suspect that something unusual is going on.

Very often, SLIders also report that they tend to have an odd effect on other electronic devices. In letters I've received, these people claim such effects as:

• Appliances such as lamps and TVs go on and off without being touched.
• Light bulbs constantly blow when the SLIder tries to turn them off or on.
• Volume levels change on TVs, radios, and CD players.
• Watches stop working.
• Children's electronic toys start by themselves when the SLIder is present.
• Credit cards and other magnetically encoded cards are damaged or erased when in their possession.

What Causes This Phenomenon?

Any attempt to pinpoint a cause for SLI at this point would be mere speculation without a thorough scientific investigation. The problem with such investigations, as with many forms of psychic phenomena, is that they are very difficult to reproduce in a laboratory. They seem to happen spontaneously without the deliberate intention of the SLIder. In fact, the SLIder, according to some informal tests, is usually unable to create the effect on demand.

A reasonable speculation for the effect, if it is a real one, might have something to do with the electronic impulses of the brain. All of our thoughts and movements are the result of electrical impulses that the brain generates. At present, it is known that these measurable impulses only have an effect on an individual's body, but is it possible that they could have an effect outside the body -- a kind of remote control?

Research at the Princeton Engineering Anomalies Research (PEAR) lab suggested that the subconscious can indeed affect electronic devices. Subjects are able to influence the random generations of a computer far more than would occur merely by chance. This research -- and research being conducted at other laboratories around the world -- are beginning to reveal, in scientific terms, the reality of such psychic phenomena as ESP, telekinesis and soon, perhaps, SLI. (Note: the PEAR lab did not specifically research SLI, and the research facility has since been closed.)

Although the SLI effect is not a conscious one, some SLIders report that when it does occur, they often are in an extreme emotional state. A state of anger or stress is often cited as the "cause." SLIder Debbie Wolf, a British barmaid, told CNN, "When it happens is when I'm stressed about something. Not really manically stressed, just when I'm really mulching something over, really chewing something over in my head, and then it happens."

Could it all be just coincidence, however? David Barlow, a graduate student of physics and astrophysics, suspects that the phenomenon might be attributed to people seeing patterns in "random noise." "It is unlikely that a light will turn itself on when you walk past it," he says, "so it is a shock when it happens. If this should happen a few times consecutively, then it appears some mechanism is at work."

SLI Research

A research project into SLI was conducted by Dr. Richard Wiseman at the University of Hertfordshire in England. In 2000, Wiseman made the newspapers with a project to test ESP with a kiosk-type machine -- called The Mind Machine -- that he set up in various locations around England to collect a large amount of data about the possible psychic abilities of the general public.

Hillary Evans, an author and paranormal investigator with The Association for the Scientific Study of Anomalous Phenomena (ASSAP), also studied the phenomenon. She established the Street Lamp Interference Data Exchange as a place where SLIders can report their experiences and share those of other SLIders. [The existence of this exchange cannot be verified at this time.]

"It's quite obvious from the letters I get," Evans told CNN, "that these people are perfectly healthy, normal people. It's just that they have some kind of ability... just a gift they've got. It may not be a gift they would like to have."