Where does desensitization collide?

In allergy and immunology, desensitization (allergen immunotherapy) is the deliberate administration of gradually increasing doses of an allergen to reduce a patient's hypersensitivity, so that later natural exposure provokes a milder reaction or none. Noon's 1911 report of prophylactic inoculation against hay fever introduced the practice of injecting graded pollen extracts to blunt seasonal symptoms. The referent is an induced, lasting drop in immune reactivity to a specific antigen, a different construct from a receptor's molecular fade or a behaviour-therapy procedure, joined to them only by the meaning of making something less responsive.[1]

Unit

The reduction in allergic response after a graded course of allergen exposure

Recovery means

Not applicable

Measured by

Gauged by symptom scores, medication use, and challenge or skin-test reactivity before and after a dosing course

In receptor pharmacology, desensitization is the waning of a receptor's response during continued or repeated exposure to its agonist, even while the agonist is still present. Katz and Thesleff's 1957 study at the neuromuscular junction showed that prolonged acetylcholine drives the receptor into a non-conducting state, and proposed a cyclic scheme in which agonist-bound receptors convert to a desensitized form. The referent is a molecular loss of responsiveness at the receptor itself, measured in the laboratory, distinct from clearing an allergy or treating a phobia.[2]

Unit

The decline in receptor-mediated response under maintained agonist exposure

Recovery means

Responsiveness returns as agonist is removed and receptors revert from the desensitized to the resting state

Measured by

Quantified by the fall in agonist-evoked current or response during sustained or repeated application

In behaviour therapy, systematic desensitization is a treatment for phobias and anxiety in which a relaxed patient is exposed, step by step, to an ordered hierarchy of increasingly feared situations, so that the fear response is progressively inhibited and extinguished. Wolpe's 1961 account built the method on reciprocal inhibition: pairing relaxation with imagined threat so the two cannot coexist. The referent is a therapeutic procedure that reduces a learned emotional response, a construct about behaviour and conditioning rather than molecules or antigens.[3]

Unit

The reduction in fear or avoidance after graded, relaxation-paired exposure

Recovery means

Not applicable

Measured by

Assessed by self-reported anxiety, avoidance behaviour, and physiological arousal before and after treatment