It's electrifying

You are walking down a lit street at night, deep in thought. Up ahead, a sodium street lamp casts an orange glow. As you approach, the light flickers for an instant, then switches off, only to come back on again once you have passed by.

Many of us will have experienced this, and it is reported often enough for parapsychologists to have given it a name, Street Light Interference (SLI). Those who feel that they are repeatedly affected refer to themselves as Sliders.

The majority of Sliding incidents are easily explained. When common sodium and mercury vapour streetlights wear out they "cycle" - flicker on and off - owing either to changes in the consistency of the vapour inside them, or to ageing electrodes. At other times, the light-sensitive cells that operate them can develop glitches, leading to whole banks of lights behaving peculiarly. On witnessing this, our pattern-detecting minds make the connection and assume that we have interfered with the light.

That, at least, is the rational answer, but naturally there are complications. Some Sliders claim to affect other electrical appliances, merely through proximity to them. Light bulbs, televisions, computers, watches and fridges may malfunction, often permanently.

Sometimes referred to as High Voltage Syndrome (HVS), cases have been recorded as far back as 1837, when a young American woman found herself dramatically charged with electricity for five months. Anyone she passed her hands over would be painfully zapped with static electricity. More recently, in 1976, after breaking his arm, 12-year-old Vyvyan Jones of Bristol found that he could illuminate light bulbs by touching them. Televisions and lights would also flicker in his presence. In 1983, Jacqueline Priestman, of Manchester, claimed to have blown up 30 vacuum cleaners, five irons and two washing machines. She also caused televisions to change channel. Another Mancunian, Mandy Boardman, got through six vacuum cleaners and six TVs in three years. Her friends said she always gave them a shock when touching them.

What causes people to retain so much static electricity is unknown, but it is not necessarily a modern condition. Despite the massive increase in electricity use, recorded instances don't seem to have risen that dramatically in the past 150 years.