Confusion is an impairment of abstract thinking demonstrated by an inability to think with one’s customary clarity and coherence.  Within the context of substance use, it is commonly experienced as a persistent inability to grasp or comprehend concepts and situations which would otherwise be perfectly understandable during sobriety. The intensity of this effect seems to to be further increased with unfamiliarity  in either setting or substance ingested.
Confusion is often accompanied by other coinciding effects such as delirium, delusions, and short-term memory suppression in a manner which further increases the person's lack of comprehension. It is most commonly induced under the influence of heavy dosages of hallucinogenic compounds, such as psychedelics  , dissociatives  , synthetic cannabinoids  , and deliriants   . However, it can also occur to a lesser extent under the influence of heavy dosages of benzodiazepines  and antipsychotics  .
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