Researchers showed that ginkgo biloba can improve the power of concentration, while ginseng sharpens up the memory.
The effect was even more powerful if the two herbs were taken together.
The researchers believe the instant hit may help students to improve exam performance, and businessmen clinch a crucial deal.
They suggest the herbs may also be useful in treating neurological disorders - ginkgo is already used in some countries to treat Alzheimer's disease.
Researcher Dr Andrew Scholey, from the University of Northumbria said: "These results suggest that such extracts may have many other medical applications such as helping people recover from local anaesthetics."
Dr Scholey said researchers had long looked for a drug that improves both memory and concentration.
"Normally when you speed people up you lose a bit of accuracy, or if they are more accurate they take longer to respond.
"These two herbs added together synergistically in a remarkable way."
Thousands of years
Both herbal extracts have been used for thousands of years in China.
They are supposed to boost energy and performance when taken over a long period of time.
However, Dr Scholey's team discovered ginkgo improved attentiveness after just one dose.
Volunteers displayed much faster reaction times in tests requiring concentration.
Dr Scholey said: "Subjects were able to sustain their concentration for longer. Normally when people have to concentrate over an extended period of time, their reaction time begins to slow - ginkgo seemed to stop that slowing and one dose actually speeded them up."
The research also showed that ginseng rapidly boosted memory.
"With every dose there was improvement in the subjects' ability to store, hold and retrieve information, and one dose caused a particularly dramatic improvement."
The most significant impact of all was when volunteers took a preparation of 60% ginseng and 40% ginkgo.
They were then asked to take part in a simple maths test, repeatedly subtracting the number seven or three from a series of figures.
Dr Scholey said: "People were performing serial sevens at the same rate as serial threes.
"This is a remarkable finding. What seems to be happening is that it is improving the available mental energy."
The most effective doses were 400mg of ginseng, 360mg of ginkgo, and 960mg of the two combined.
Ginkgo biloba and ginseng are widely available in health food shops and chemists.
But the combined remedy cannot yet be obtained in the UK.
One ginkgo-ginseng extract, marketed as Ginkoba, is available in the United States and some European countries.
The researchers presented their results at the British Psychological Society's annual conference in Winchester.
The study was funded by Pharmaton, a company that produces ginkgo and ginseng preparations, but Dr Scholey insisted the research was scrupulously independent.
Dr Richard Harvey, director of research, Alzheimer's Society said: "Gingko does not halt or affect the progress of dementia.
"However, some research has shown improvement in the attention and memory of people with who took capsules of the plant extract in trials."
Dr Peter May, a GP in Southampton, warned that proper clinical trials would be needed before the herbs were used to treat medical conditions.
He said: "Anything that has an effect, in all probability, also has a side effect. We don't know what effect these remedies may have on the action of other drugs."