Plants have been used for medicinal purposes throughout human history and although it may seem to us that modern life is innately much more stressful than long ago, the struggle for basic survival then must have been at least as worrying as the more 'sophisticated' concerns of today. Thus, it seems likely that healers in primitive societies probably had to treat exactly the same range of disorders as those with which we are familiar. Spells and incantations to drive away evil spirits, which some may interpret as early psychotherapy, might have been combined with the use of herbs with psychoactive properties.