Possible mechanisms for why desensitization and exposure therapy work

https://doi.org/10.1016/j.cpr.2004.08.005Get rights and content

Abstract

Rosen and Davison [Rosen, G.M. and Davison, G.C. (2003). Psychology should list empirically supported principles of change (ESPs) and not credential trademarked therapies or other treatment packages. Behavior Modification, 27, 300–312] recommended that empirically supported principles be listed instead of empirically supported treatments because the latter approach enables the creation of putatively new therapies by adding functionally inert components to already listed effective treatments. This article attempts to facilitate inquiry into empirically supported principles by reviewing possible mechanisms responsible for the effectiveness of systematic desensitization and exposure therapy. These interventions were selected because they were among the first empirically supported treatments for which some attempt was made at explanation. Reciprocal inhibition, counterconditioning, habituation, extinction, two-factor model, cognitive changes including expectation, self-efficacy, cognitive restructuring, and informal network-based emotional processing explanations are considered. Logical problems and/or available empirical evidence attenuate or undercut these explanations. A connectionist learning-memory mechanism supported by findings from behavioral and neuroscience research is provided. It demonstrates the utility of preferring empirically supported principles over treatments. Problems and limitations of connectionist explanations are presented. This explanation warrants further consideration and should stimulate discussion concerning empirically supported principles.

Section snippets

Possible mechanisms for why desensitization and exposure therapy work

Psychologists seem to agree, and our professional ethics require, that only reliable and valid psychological tests should be used. The new ethics code states that “Psychologists use assessment instruments whose validity and reliability have been established for use with members of the population tested” (APA, 2002, p. 1071). Less agreement exists regarding psychotherapy. The extent to which interventions are to be based on and informed by scientific research is one of the primary professional

Explanatory bases and possible principles

We now understand that systematic desensitization depends upon exposure but the two therapies are treated separately here because that is how the explanatory literature is organized. Most literature citations regarding the explanatory basis of systematic desensitization are old because exposure therapy all but replaced it subsequent to Marks (1975) literature review and because research has focused almost exclusively on outcome research, hypothesis testing, and novel prediction since then. The

Empirically supported mechanisms

Parallel Distributed Processing Connectionist Neural Network (PDP-CNN) models are memory mechanisms that learn. Both learning and memory are driven by experience which makes both processes dependent upon sensation and perception. Hence, action mechanisms associated with the processes of learning, memory, sensation, and perception are pertinent to our understanding of how systematic desensitization and exposure therapy work. Some information regarding empirically supported PDP-CNN mechanisms is

Synaptic change

The network model presented above is empirically supported by evidence from neuroscience laboratories that has clearly demonstrated that learning and memory entail synaptic change; i.e., brain placticity. Connectionist models are memory systems that learn.

Neuroimaging studies

Kandel (1991) hypothesized that the biological changes produced by learning should be detectable with modern neuroimaging equipment. Baxter et al. (1992) reported PET results showing that nine OCD patients treated with CBT for 10 weeks

Weaknesses and limitations of connectionist explanations

The emerging field of PDP connectionism is not without its limitations and problems. O'Reilly and Munakata (2000) noted, “… the history of neural network modeling has been dominated by periods of either extreme hype or extreme skepticism” (p. 413). These authors summarized general and specific challenges to computational models (pp. 413–421): (a) PDP-CNN models have been criticized as being too simple thereby omitting potentially important details. Alternatively, simplification has been viewed

Conclusions

Reciprocal inhibition, counterconditioning, habituation, extinction, two-factor model, cognitive changes including expectation, self-efficacy, and cognitive restructuring, and emotional processing were considered as possible explanatory mechanisms for the effectiveness of systematic desensitization and exposure therapy. Various problems were identified that attenuate or undercut their explanatory force. A connectionist network cascade mechanism was presented that provides information beyond

Uncited references

Davis & Palladino, 2000

Noll, 1995

Tierney, 1995

References (171)

  • E.B. Foa et al.

    Behavioral/cognitive conceptualization of post-traumatic stress disorder

    Behavior Therapy

    (1989)
  • J. Fodor

    Connectionism and the problem of systematicity (continued): Why Smolensky's solution still doesn't work

    Cognition

    (1997)
  • J. Fodor et al.

    Connectionism and the problem of systematicity: Why Smolensky's solution doesn't work

    Cognition

    (1990)
  • J.A. Fodor et al.

    Connectionism and cognitive architecture: A critical analysis

    Cognition

    (1988)
  • N.W. Freeling et al.

    The alleviation of test anxiety by systematic desensitization

    Behaviour Research and Therapy

    (1970)
  • M.A. Gluck et al.

    Computational models of the hippocampal region: Linking incremental learning and episodic memory

    Trends in Cognitive Sciences

    (2003)
  • J.C. Jones et al.

    The etiology of post-traumatic stress disorder

    Clinical Psychology Review

    (1990)
  • W. Kass et al.

    Drive level, incentive conditions and systematic desensitization

    Behaviour Research and Therapy

    (1974)
  • R.A. Kleinknecht

    Acquisition of blood, injury and needle fears and phobias

    Behaviour Research and Therapy

    (1994)
  • M.H. Lader et al.

    A physiological model of phobic anxiety and desensitization

    Behaviour Research and Therapy

    (1968)
  • P.J. Lang

    Imagery in therapy: An information processing analysis of fear

    Behavior Therapy

    (1977)
  • D.J. Levis

    Implosive therapy

  • G.F. Marcus

    Can connectionism save constructivism?

    Cognition

    (1998)
  • G.F. Marcus

    Rethinking eliminative connectionism

    Cognitive Psychology

    (1998)
  • G.F. Marcus

    Connectionism: With or without rules?

    Trends in Cognitive Sciences

    (1999)
  • W.S. Agras et al.

    Relaxation in systematic desensitization

    Archives of General Psychiatry

    (1971)
  • APA

    Ethical principles of psychologists and code of conduct

    American Psychologist

    (2002)
  • A. Bandura

    Principles of behavior modification

    (1969)
  • A. Bandura

    Self-efficacy: Toward a unifying theory of behavior change

    Psychological Review

    (1977)
  • A. Bandura

    The self system in reciprocal determinism

    American Psychologist

    (1978)
  • A. Bandura

    Self-efficacy mechanism in human agency

    American Psychologist

    (1982)
  • A. Bandura

    Self-Efficacy: The exercise of control

    (1998)
  • R.M. Baron et al.

    The moderator-mediator variable distinctions in social psychological research: Conceptual, strategic, and statistical considerations

    Journal of Personality and Social Psychology

    (1986)
  • T.W. Baskin et al.

    Establishing specificity in psychotherapy: A meta-analysis of structural equivalence of placebo controls

    Journal of Counseling and Clinical Psychology

    (2003)
  • L.R. Baxter et al.

    Caudate glucose metabolic rate changes with both drug and behavior therapy for obsessive–compulsive disorder

    Archives of General Psychiatry

    (1992)
  • W. Bechtel et al.

    Connectionism and the mind: Parallel processing, dynamics, and evolution in networks

    (2002)
  • A.T. Beck

    Cognitive therapy and the emotional disorders

    (1976)
  • J.S. Beck

    Cognitive therapy: Basics and beyond

    (1995)
  • S. Benjamin et al.

    Active muscular relaxation in desensitization of phobic patients

    Psychological Medicine

    (1972)
  • S.W. Bottjer et al.

    Developmental plasticity in neural circuits for a learned behavior

    Annual Review of Neuroscience

    (1997)
  • P.J. Bowler

    The eclipse of Darwinism: Anti-Darwinian evolution theories in the decades around 1900

    (1983)
  • C.R. Brewin et al.

    A dual representation theory of Posttraumatic Stress Disorder

    Psychological Review

    (1996)
  • H.A. Brown

    Role of expectancy manipulation in systematic desensitization

    Journal of Consulting and Clinical Psychology

    (1973)
  • M.L. Commons et al.

    Neural network models of conditioning and action

    (1991)
  • G. Cooke

    Evaluation of the efficacy of the components of reciprocal inhibition psychotherapy

    Journal of Abnormal Psychology

    (1968)
  • W.E. Craighead

    The role of muscular relaxation in systematic desensitization

  • M. Creamer et al.

    Reaction to trauma: A cognitive processing model

    Journal of Abnormal Psychology

    (1992)
  • C. Darwin

    The origin of species: By means of natural selection or the preservation of favoured races in the struggle for life

    (1859)
  • S.F. Davis et al.

    Psychology

    (2000)
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