Final answer:
Dexter is utilizing the technique of distraction to alleviate the pain of a hypodermic needle injection. This method is a psychological approach that diverts focus away from the painful stimulus, thus reducing the perception of pain.
Step-by-step explanation:
To reduce his experience of pain, Dexter is using the pain control technique of distraction. By focusing on a picture on the wall instead of the injection, Dexter diverts his attention away from the painful stimulus, which can help reduce the perception of pain. This technique is neither related to medication, which involves the use of drugs to relieve pain; hypnosis, which is a state of extreme self-focus used to alter thoughts and perceptions; nor physical therapy, which uses physical methods to alleviate pain and improve function.
While psychoactive drugs may be used for pain control, such as general anesthetics like halothane and ketamine, or opioids like morphine and codeine, Dexter's choice of technique does not involve medication. Instead, distraction is a psychological technique that can be quite effective in mitigating the immediate experience of pain.