In 1956, British psychiatrist Humphry Osmond coined the word “psychedelic” from Greek roots meaning “mind-manifesting” or “soul-revealing.” The term proved fitting. Users report that seconds stretch into eternity, sounds turn into color, and you very self begins dissolving. And now, after decades in scientific exile, those same once-ostracized compounds are undergoing a dramatic scientific renaissance. Researchers are investigating them not only for depression, trauma, and addiction, but also as a potential window into one of neuroscience’s deepest mysteries: how the brain constructs reality itself. And a small, egg-shaped structure buried deep in the center of the brain, the thalamus, may play an important role in that process.
Scientists once viewed the thalamus largely as a relay station: a kind of biological switchboard routing sensory information to the cortex, the brain’s outer layer responsible for higher thought, perception, and conscious awareness. But newer theories suggest something far stranger. Increasingly, neuroscientists suspect reality may partly reflect the brain’s constantly updated “best guess” about the world—built from memory, expectation, sensory input, and context, as Michelle J. Redinbaugh, PhD, a neuroscientist at Stanford University, puts it.
Hellbound and Down 