Operant procedures and the comatose patient.
Favorite music can act as reinforcement for small movements in recently comatose adults, giving a first signal of awareness.
01Research in Context
What this study did
Sarber et al. (1983) worked with three adults who had been in comas after brain injury.
The team played each patient’s favorite music only when the patient moved a finger or opened an eye.
They used an ABAB reversal design to see if the music truly caused the movement.
What they found
The patient who had been in a coma the shortest time moved more when music played.
The two patients who had been in comas longer showed only small, uneven gains.
Music worked as reinforcement, but coma length mattered.
How this fits with other research
Lancioni et al. (2009) extends this idea. They gave post-coma adults microswitches that played music or called staff. Both patients learned to hit the switch, showing choice and intent.
DeVellis et al. (1979) used the same ABAB design with awake children in a pediatric ICU. Simple activities raised happy behavior, proving brief contingent events work in medical beds.
Konstantareas (1987) reviewed operant studies from the same era. The review reminds us that early gains can fade; long-term change needs more than just reinforcement.
Why it matters
You can test for awareness in vegetative adults by offering loved music as a reinforcer. Start with patients who have been in coma less than a few weeks; they are more likely to show a clear response. Pair the music with a simple motor target you can count, and run a quick reversal to be sure the contingency is working. If the patient responds, you have evidence of voluntary behavior and a first step toward communication.
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Join Free →Pick one short-duration coma patient, select a loved song, and deliver 10 s of music each time the patient flexes a finger; graph the flexes across three on-off cycles.
02At a glance
03Original abstract
Operant procedures were tested on three patients who had been in vegetative coma for 6 months, 10 months, and 38 months. A discrete trial procedure was used to test compliance to verbal requests for three behaviors for each patient, including lateral head movement or finger movement, eye focus or eye squeeze, and mouth movement. The design for each patient consisted of multiple baselines across three behaviors with a withdrawal phase and a reinstatement phase (ABAB) for one behavior. Baseline phases were followed by contingent music phases in which 15-second taped excerpts of patients' preferred music sounded immediately following the emission of targeted behaviors. The contingent music treatment affected all three behaviors for Patient 1, but was less effective for two out of three behaviors for the second and third patients who had been in coma for more extensive periods of time. Results are discussed in terms of the potential contributions of the use of operant assessment and treatment procedures in an area of medicine where they have not been used before.
Journal of applied behavior analysis, 1983 · doi:10.1901/jaba.1983.16-3