Those with schizophrenia who stop responding to their environment and remain motionless and silent for long periods of time are experiencing: a. catatonic posturing. b. catatonic rigidity. c. catatonic excitement. d. catatonic stupor.

They are experiencing "Catatonic Stupor", "D".

Catatonia is a condition of psycho-motor stability and behavioral variation from the norm showed by stupor. It was first portrayed in 1874 by Karl Ludwig Kahlbaum. Catatonia is accepted to be caused by inconsistencies in the dopamine, gamma-aminobutyric Acid (GABA), and glutamate neurotransmitter frameworks. It's frequently joined by a hidden neurological, mental, or physical disease. Subsequently, your specialist must spotlight on the reason to treat catatonic side effects effectively.

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