The chemical and psychological factors involved in the fascinating phenomenon of the brain's conception of time will be explored in a public lecture by Dr Harry Witchel of Bristol University and Dr Andy Bass of Aston University at the Cheltenham Festival of Science on Saturday, June 7.

The lecture, Moments of Ecstasy - the Subjective Experience of Time, is aimed at the general public with no specific background in science. It will present demonstrations and information about how science has answered the question, "Why does time fly when you're having fun?"

Drawing from issues concerning sex, sport, meditation and pain, Dr Witchel and Dr Bass will examine the chemical and psychological aspects of the brain's subjective experience of time.

Dr Witchel said: "The lecture will explore events we all experience in our day-to-day lives, for example, waiting for a long time at a stop light. Even when you're not looking at a clock, at a certain point your brain knows you've been waiting too long, and you might start wondering if the light is broken.

"We'll also be looking at conundrums about how we perceive the world in time and the possibilities of 'microconsciousness'."

Dr Witchel is a Research Associate in the University's Department of Physiology. He is dedicated to making science more accessible to the public by talking about important scientific findings and relating them to everyday experiences in life. He has appeared numerous times on radio and television, and his lecture with Dr Bass at last year's Cheltenham Science Festival, entitled The Chemicals of Pleasure, sold out.

Moments of Ecstasy - the Subjective Experience of Time, Saturday, June 7 1pm - 2pm, Town Hall, Cheltenham. £4 (£3 concessions)