Final answer:
The case study describes the therapist utilizing 'free association,' which is a technique where the patient is encouraged to verbally express any thoughts without censorship as part of psychoanalysis.
Step-by-step explanation:
The technique used by the therapist in the case study, where the therapist encouraged Mary to say whatever came to mind, is known as free association. This psychoanalytic technique was developed by Sigmund Freud and is central to the practice of psychoanalysis. Free association allows patients to explore their unconscious thoughts and feelings by expressing whatever ideas come to mind without censoring or filtering them. This contrasts with other psychoanalytic techniques such as dream analysis, where the therapist interprets the content of dreams, transference, where the patient projects feelings about other people onto the therapist, or resistance, where the patient unconsciously avoids certain topics or thoughts.