Physical autonomy can be described as the experience of a person's own body performing simple or complex actions entirely of its own accord. Depending on the intensity, this results in the carrying out of a given task becoming partially to completely automatic in nature without the requirement of decision-making skills or attentive conscious input.
At lower levels, the effect is partially controllable by commanding the body with simple thoughts. For example, thoughts such as "go to the toilet" or "go drink a glass of water" can result in the body performing these actions autonomously. This can often help the person perform necessary physical actions such as tending to bodily functions or avoiding danger when they would otherwise be too incapable, unconscious, or distractible to perform them manually in their current state.
At higher levels, this effect no longer requires verbal commands and becomes entirely automatic. It's worth noting that although this technically results in a loss of cognitive control, the body only performs actions which the owner would have decided to perform were they capable of it themselves.
Physical autonomy is often accompanied by other coinciding effects such as physical disconnection and cognitive disconnection. It is most commonly induced under the influence of heavy dosages of dissociative compounds, such as ketamine, PCP, and DXM. However, it can also occur to a lesser extent under the influence of heavy dosages of psychedelics such as LSD, psilocybin, and mescaline.