# Researchers say evidence from Indonesia suggests humans may have been using psychoactive plants as far back as 25-thousand years ago. The study focuses on ancient plant remains discovered in a cave on the island of Sulawesi, including traces of naturally occurring substances that can affect the brain. Scientists say the findings could push back the earliest known evidence of deliberate drug use by thousands of years. The discovery also provides clues about how prehistoric people may have used plants for ritual, medicinal or recreational purposes.
Drug use may date back 25,000 years