- Email: [email protected]
On nonassociative fear emergence
Behaviour Research and Therapy 40 (2002) 169–172 www.elsevier.com/locate/brat
On nonassociative fear emergence Richard J. McNally
*
Department of Psychology, Harvard University, 33 Kirkland Street, Cambridge, MA 02138, USA
Abstract Poulton and Menzies have articulated a nonassociative alternative to traditional conditioning theories of phobia emergence. Prompted by their essay, I address several issues including controversies about what counts as a conditioning event, difficulties establishing whether a fear functioned as an adaptation throughout evolutionary history, hazards of attempting to recover conditioning events in the histories of patients, and problems with the contingency view of associative learning. 2002 Elsevier Science Ltd. All rights reserved. Keywords: Conditioning; Phobias; Evolutionary psychology
1. On nonassociative fear emergence Conditioning theories of fears and phobias have long been characterized by a paradox. On the one hand, they have inspired the development of effective behavioral treatments, dethroning psychoanalytic approaches in the process (Wolpe & Rachman, 1960). On the other hand, they cannot explain the emergence of the many phobias that do not originate in Pavlovian pairings of conditioned (CSs) and unconditioned stimuli (USs). Despite their manifest difficulties explaining fear acquisition, conditioning theories are still with us. But all theories are adrift in a sea of anomalies, and recalcitrant facts do not “falsify” a theory until a plausible alternative is proposed. Synthesizing old facts and new findings, Poulton and Menzies (in press) have proposed just such an alternative. The purpose of my article is to comment on several issues addressed in their essay. Evaluating conditioning theories of fears and phobias has been complicated by failures to clarify what counts as a conditioning event (McNally & Steketee, 1985). Critics hold that conditioning is usually irrelevant because phobics rarely report encountering USs akin to the electric shocks delivered in the laboratory (e.g., Marks, 1987, p. 329). In contrast, despite the absence of a US,
* Tel.: +1 617 495 3853; fax: +1 617 495 3728. E-mail address: [email protected] (R.J. McNally).
0005-7967/02/$ - see front matter 2002 Elsevier Science Ltd. All rights reserved. PII: S 0 0 0 5 - 7 9 6 7 ( 0 1 ) 0 0 0 4 9 - 3
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R.J. McNally / Behaviour Research and Therapy 40 (2002) 169–172
advocates consider sudden terror in the presence of the to-be-feared stimuli as conditioning events ¨ st & Hugdahl, 1983). This formulation, of course, begs that explain the subsequent phobia (e.g., O the question of why the person experienced terror in the first place. Poulton and Menzies drive this point home in their discussion of water phobia. In approximately 50%–75% of cases, parents claim that their water-phobic child exhibited intense fear during his or her first encounter with water (e.g., at the beach or pool). Because there is nothing akin to a US to explain this fear, Poulton and Menzies rightly interpret these data as inconsistent with a conditioning account. Yet inexplicable terror in the presence of neutral stimuli is what gets counted as a conditioning event by conditioning theorists! Evolutionary considerations predominate in nonassociative theory. Whereas Poulton and Menzies suggest that associative learning often explains the emergence of fears of contemporary threats (e.g., driving phobia), nonassociative processes more often explain the emergence of fears having evolutionary significance (e.g., height phobia) that are presumably susceptible to reinstatement via nonspecific stress (Jacobs & Nadel, 1985; but see McNally, 1989 for a critique). Unfortunately, determining what fears functioned as adaptations throughout the history of our species is a dauntingly difficult task, as Poulton and Menzies acknowledge. Formulating plausible evolutionary scenarios is easy, but testing them is another matter, and this is especially true for human cognition (Lewontin, 1998) and psychopathology (McNally, 2001). Assuming that certain fears did, in fact, foster fitness in ancestral populations, we still must identify those having evolutionary significance and thus likely to require a nonassociative explanation. For example, spider phobia is often deemed a “biologically prepared” fear, yet only 0.1% of the 35,000 varieties are dangerous to human beings (F. Renner, 1990; cited in Merckelbach & de Jong, 1997). How should we classify airplane phobia? Is it a contemporary fear, like driving phobia, or a subset of height phobia? Fear of suffocating on food might qualify as a fear having evolutionary significance, yet choking phobia almost always originates in a conditioning episode (McNally, 1994). Poulton and Menzies concede that some fears may be explained better by preparedness theory than by nonassociative theory, citing Mineka’s ingenious experiments on snake fear acquisition in nonhuman primates as a case in point (e.g., Cook & Mineka, 1989). Ironically, data on snake fear in rhesus monkeys may be consistent with Poulton and Menzies’s theory after all. As Kalin (2000) has emphasized, rhesus monkeys do exhibit snake fear prior to any relevant associative experiences. Working in the Wisconsin primate laboratory and using measures apparently more sensitive than those of Mineka, Kalin found that fear is, indeed, detectable in snake-naive monkeys. Poulton and Menzies wisely counsel clinicians to avoid insisting that conditioning episodes are the source of every phobia. They also state that “Obviously, an individual cannot be expected to recall events that have never occurred” (p. 26). Although people, by definition, cannot correctly recall something that has never occurred, some people have apparently “recalled” childhood sexual abuse (CSA) events that may have never happened. Our group has completed a series of psychometric and laboratory studies on people who report recovered memories of CSA (Clancy, McNally, & Schacter, 1999; Clancy, Schacter, McNally, & Pitman, 2000; McNally, in press; McNally, Clancy, & Schacter, 2001; McNally, Clancy, Schacter, & Pitman, 2000a,b). Not all the traumatic conditioning events remembered by our participants are plausible (e.g., abuse recollections from early infancy). More recently, we have been studying people who report recovered memories of being abducted and molested by space aliens (Clancy, McNally, Schacter, Len-
R.J. McNally / Behaviour Research and Therapy 40 (2002) 169–172
171
zenweger, & Pitman, 2001). Suffice it to say, these reports suggest that people may “recall” conditioning events that are unlikely to have occurred. Noting that mere contiguity between CS and US is insufficient for associative learning, Poulton and Menzies hold that contingency is “critical for fear acquisition in the laboratory” (p. 3). Yet after reviewing the experimental literature, Papini and Bitterman (1990) concluded that: CS-US contingency is neither necessary nor sufficient for conditioning and that the concept has long outlived any usefulness it may once have had in the analysis of conditioning. (p. 396) Because facile “pseudoevolutionary thinking” (Papini & Bitterman, 1990, p. 401) and “Complacent speculation about adaptive value takes the place of critical analysis” (Papini & Bitterman, 1990, p. 397), the contingency interpretation of Pavlovian conditioning has persisted despite massive amounts of inconsistent data. In conclusion, Poulton and Menzies should be congratulated for articulating a fresh perspective on the emergence of fears and phobias and for testing their nonassociative account empirically. Their chief theoretical rival will likely be a modernized version of conditioning theory that does justice to the complexities of associative learning (Mineka & Zinbarg, 1996). Unfortunately, modernized theories run the risk of adding so many auxiliary assumptions that devising decisive empirical tests becomes difficult. This problem arises whenever scientists attempt to extrapolate principles from highly controlled laboratory settings to the uncontrolled, open system of the clinical world (McNally, 2000).
References Clancy, S. A., McNally, R. J., & Schacter, D. L. (1999). Effects of guided imagery on memory distortion in women reporting recovered memories of sexual abuse. Journal of Traumatic Stress, 12, 559–569. Clancy, S. A., McNally, R. J., Schacter, D. L., Lenzenweger, M. F., & Pitman, R. K. (2001). Memory distortion in people reporting abduction by aliens. Manuscript submitted for publication. Clancy, S. A., Schacter, D. L., McNally, R. J., & Pitman, R. K. (2000). False recognition in women reporting recovered memories of sexual abuse. Psychological Science, 11, 26–31. Cook, M., & Mineka, S. (1989). Observational conditioning of fear to fear-relevant versus fear-irrelevant stimuli in rhesus monkeys. Journal of Abnormal Psychology, 98, 448–459. Jacobs, W. J., & Nadel, L. (1985). Stress-induced recovery of fears and phobias. Psychological Review, 92, 512–531. Kalin, N. H. (2000). Animal models: Genes and environment. Lecture delivered in the satellite research symposium entitled Genetics and brain function: Implications for the treatment of anxiety. Anxiety Disorders Association of America. March 2000, Washington, DC. Lewontin, R. C. (1998). The evolution of cognition: Questions we will never answer. In D. Scarborough, & S. Sternberg, An invitation to cognitive science: (2nd ed.) (pp. 105–132). Methods, models, and conceptual issues, vol. 4. Cambridge, MA: MIT Press. Marks, I. M. (1987). Fears, phobias, and rituals. New York: Oxford University Press. Merckelbach, H., & de Jong, P. J. (1997). Evolutionary models of phobias. In G. C. L. Davey, Phobias: A handbook of theory, research, and treatment (pp. 323–347). Chichester, UK: Wiley. McNally, R. J. (1989). On “Stress-induced recovery of fears and phobias”. Psychological Review, 96, 180–181. McNally, R. J. (1994). Choking phobia: A review of the literature. Comprehensive Psychiatry, 35, 83–89. McNally, R. J. (2000). Emotion research in cognitive-behavior therapy: Obstacles to application. Clinical Psychology: Science and Practice, 7, 400–402.
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R.J. McNally / Behaviour Research and Therapy 40 (2002) 169–172
McNally, R. J. (2001). On Wakefield’s harmful dysfunction analysis of mental disorder. Behaviour Research and Therapy, 39, 309–314. McNally, R. J. (in press). The cognitive psychology of repressed and recovered memories of childhood sexual abuse: Clinical implications. Psychiatric Annals. McNally, R. J., Clancy, S. A., & Schacter, D. L. (2001). Directed forgetting of trauma cues in adults reporting repressed or recovered memories of childhood sexual abuse. Journal of Abnormal Psychology, 110, 151–156. McNally, R. J., Clancy, S. A., Schacter, D. L., & Pitman, R. K. (2000a). Personality profiles, dissociation, and absorption in women reporting repressed, recovered, or continuous memories of childhood sexual abuse. Journal of Consulting and Clinical Psychology, 68, 1033–1037. McNally, R. J., Clancy, S. A., Schacter, D. L., & Pitman, R. K. (2000b). Cognitive processing of trauma cues in adults reporting repressed, recovered, or continuous memories of childhood sexual abuse. Journal of Abnormal Psychology, 109, 355–359. McNally, R. J., & Steketee, G. S. (1985). The etiology and maintenance of severe animal phobias. Behaviour Research and Therapy, 23, 431–435. Mineka, S., & Zinbarg, R. (1996). Conditioning and ethological models of anxiety disorders: Stress-in-dynamic-context anxiety models. Nebraska Symposium on Motivation, 43, 135–210. ¨ st, L.-G., & Hugdahl, K. (1983). Acquisition of agoraphobia, mode of onset and anxiety response patterns. Behaviour O Research and Therapy, 21, 623–631. Papini, M. R., & Bitterman, M. E. (1990). The role of contingency in classical conditioning. Psychological Review, 97, 396–403. Poulton, R., & Menzies, R. G. (in press). Non-associative fear acquisition: A review of the evidence from retrospective and longitudinal research. Behaviour Research and Therapy. Wolpe, J., & Rachman, S. (1960). Psychoanalytic “evidence”: A critique based on Freud’s case of Little Hans. Journal of Nervous and Mental Disease, 131, 135–148.
On nonassociative fear emergence Richard J. McNally
*
Department of Psychology, Harvard University, 33 Kirkland Street, Cambridge, MA 02138, USA
Abstract Poulton and Menzies have articulated a nonassociative alternative to traditional conditioning theories of phobia emergence. Prompted by their essay, I address several issues including controversies about what counts as a conditioning event, difficulties establishing whether a fear functioned as an adaptation throughout evolutionary history, hazards of attempting to recover conditioning events in the histories of patients, and problems with the contingency view of associative learning. 2002 Elsevier Science Ltd. All rights reserved. Keywords: Conditioning; Phobias; Evolutionary psychology
1. On nonassociative fear emergence Conditioning theories of fears and phobias have long been characterized by a paradox. On the one hand, they have inspired the development of effective behavioral treatments, dethroning psychoanalytic approaches in the process (Wolpe & Rachman, 1960). On the other hand, they cannot explain the emergence of the many phobias that do not originate in Pavlovian pairings of conditioned (CSs) and unconditioned stimuli (USs). Despite their manifest difficulties explaining fear acquisition, conditioning theories are still with us. But all theories are adrift in a sea of anomalies, and recalcitrant facts do not “falsify” a theory until a plausible alternative is proposed. Synthesizing old facts and new findings, Poulton and Menzies (in press) have proposed just such an alternative. The purpose of my article is to comment on several issues addressed in their essay. Evaluating conditioning theories of fears and phobias has been complicated by failures to clarify what counts as a conditioning event (McNally & Steketee, 1985). Critics hold that conditioning is usually irrelevant because phobics rarely report encountering USs akin to the electric shocks delivered in the laboratory (e.g., Marks, 1987, p. 329). In contrast, despite the absence of a US,
* Tel.: +1 617 495 3853; fax: +1 617 495 3728. E-mail address: [email protected] (R.J. McNally).
0005-7967/02/$ - see front matter 2002 Elsevier Science Ltd. All rights reserved. PII: S 0 0 0 5 - 7 9 6 7 ( 0 1 ) 0 0 0 4 9 - 3
170
R.J. McNally / Behaviour Research and Therapy 40 (2002) 169–172
advocates consider sudden terror in the presence of the to-be-feared stimuli as conditioning events ¨ st & Hugdahl, 1983). This formulation, of course, begs that explain the subsequent phobia (e.g., O the question of why the person experienced terror in the first place. Poulton and Menzies drive this point home in their discussion of water phobia. In approximately 50%–75% of cases, parents claim that their water-phobic child exhibited intense fear during his or her first encounter with water (e.g., at the beach or pool). Because there is nothing akin to a US to explain this fear, Poulton and Menzies rightly interpret these data as inconsistent with a conditioning account. Yet inexplicable terror in the presence of neutral stimuli is what gets counted as a conditioning event by conditioning theorists! Evolutionary considerations predominate in nonassociative theory. Whereas Poulton and Menzies suggest that associative learning often explains the emergence of fears of contemporary threats (e.g., driving phobia), nonassociative processes more often explain the emergence of fears having evolutionary significance (e.g., height phobia) that are presumably susceptible to reinstatement via nonspecific stress (Jacobs & Nadel, 1985; but see McNally, 1989 for a critique). Unfortunately, determining what fears functioned as adaptations throughout the history of our species is a dauntingly difficult task, as Poulton and Menzies acknowledge. Formulating plausible evolutionary scenarios is easy, but testing them is another matter, and this is especially true for human cognition (Lewontin, 1998) and psychopathology (McNally, 2001). Assuming that certain fears did, in fact, foster fitness in ancestral populations, we still must identify those having evolutionary significance and thus likely to require a nonassociative explanation. For example, spider phobia is often deemed a “biologically prepared” fear, yet only 0.1% of the 35,000 varieties are dangerous to human beings (F. Renner, 1990; cited in Merckelbach & de Jong, 1997). How should we classify airplane phobia? Is it a contemporary fear, like driving phobia, or a subset of height phobia? Fear of suffocating on food might qualify as a fear having evolutionary significance, yet choking phobia almost always originates in a conditioning episode (McNally, 1994). Poulton and Menzies concede that some fears may be explained better by preparedness theory than by nonassociative theory, citing Mineka’s ingenious experiments on snake fear acquisition in nonhuman primates as a case in point (e.g., Cook & Mineka, 1989). Ironically, data on snake fear in rhesus monkeys may be consistent with Poulton and Menzies’s theory after all. As Kalin (2000) has emphasized, rhesus monkeys do exhibit snake fear prior to any relevant associative experiences. Working in the Wisconsin primate laboratory and using measures apparently more sensitive than those of Mineka, Kalin found that fear is, indeed, detectable in snake-naive monkeys. Poulton and Menzies wisely counsel clinicians to avoid insisting that conditioning episodes are the source of every phobia. They also state that “Obviously, an individual cannot be expected to recall events that have never occurred” (p. 26). Although people, by definition, cannot correctly recall something that has never occurred, some people have apparently “recalled” childhood sexual abuse (CSA) events that may have never happened. Our group has completed a series of psychometric and laboratory studies on people who report recovered memories of CSA (Clancy, McNally, & Schacter, 1999; Clancy, Schacter, McNally, & Pitman, 2000; McNally, in press; McNally, Clancy, & Schacter, 2001; McNally, Clancy, Schacter, & Pitman, 2000a,b). Not all the traumatic conditioning events remembered by our participants are plausible (e.g., abuse recollections from early infancy). More recently, we have been studying people who report recovered memories of being abducted and molested by space aliens (Clancy, McNally, Schacter, Len-
R.J. McNally / Behaviour Research and Therapy 40 (2002) 169–172
171
zenweger, & Pitman, 2001). Suffice it to say, these reports suggest that people may “recall” conditioning events that are unlikely to have occurred. Noting that mere contiguity between CS and US is insufficient for associative learning, Poulton and Menzies hold that contingency is “critical for fear acquisition in the laboratory” (p. 3). Yet after reviewing the experimental literature, Papini and Bitterman (1990) concluded that: CS-US contingency is neither necessary nor sufficient for conditioning and that the concept has long outlived any usefulness it may once have had in the analysis of conditioning. (p. 396) Because facile “pseudoevolutionary thinking” (Papini & Bitterman, 1990, p. 401) and “Complacent speculation about adaptive value takes the place of critical analysis” (Papini & Bitterman, 1990, p. 397), the contingency interpretation of Pavlovian conditioning has persisted despite massive amounts of inconsistent data. In conclusion, Poulton and Menzies should be congratulated for articulating a fresh perspective on the emergence of fears and phobias and for testing their nonassociative account empirically. Their chief theoretical rival will likely be a modernized version of conditioning theory that does justice to the complexities of associative learning (Mineka & Zinbarg, 1996). Unfortunately, modernized theories run the risk of adding so many auxiliary assumptions that devising decisive empirical tests becomes difficult. This problem arises whenever scientists attempt to extrapolate principles from highly controlled laboratory settings to the uncontrolled, open system of the clinical world (McNally, 2000).
References Clancy, S. A., McNally, R. J., & Schacter, D. L. (1999). Effects of guided imagery on memory distortion in women reporting recovered memories of sexual abuse. Journal of Traumatic Stress, 12, 559–569. Clancy, S. A., McNally, R. J., Schacter, D. L., Lenzenweger, M. F., & Pitman, R. K. (2001). Memory distortion in people reporting abduction by aliens. Manuscript submitted for publication. Clancy, S. A., Schacter, D. L., McNally, R. J., & Pitman, R. K. (2000). False recognition in women reporting recovered memories of sexual abuse. Psychological Science, 11, 26–31. Cook, M., & Mineka, S. (1989). Observational conditioning of fear to fear-relevant versus fear-irrelevant stimuli in rhesus monkeys. Journal of Abnormal Psychology, 98, 448–459. Jacobs, W. J., & Nadel, L. (1985). Stress-induced recovery of fears and phobias. Psychological Review, 92, 512–531. Kalin, N. H. (2000). Animal models: Genes and environment. Lecture delivered in the satellite research symposium entitled Genetics and brain function: Implications for the treatment of anxiety. Anxiety Disorders Association of America. March 2000, Washington, DC. Lewontin, R. C. (1998). The evolution of cognition: Questions we will never answer. In D. Scarborough, & S. Sternberg, An invitation to cognitive science: (2nd ed.) (pp. 105–132). Methods, models, and conceptual issues, vol. 4. Cambridge, MA: MIT Press. Marks, I. M. (1987). Fears, phobias, and rituals. New York: Oxford University Press. Merckelbach, H., & de Jong, P. J. (1997). Evolutionary models of phobias. In G. C. L. Davey, Phobias: A handbook of theory, research, and treatment (pp. 323–347). Chichester, UK: Wiley. McNally, R. J. (1989). On “Stress-induced recovery of fears and phobias”. Psychological Review, 96, 180–181. McNally, R. J. (1994). Choking phobia: A review of the literature. Comprehensive Psychiatry, 35, 83–89. McNally, R. J. (2000). Emotion research in cognitive-behavior therapy: Obstacles to application. Clinical Psychology: Science and Practice, 7, 400–402.
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R.J. McNally / Behaviour Research and Therapy 40 (2002) 169–172
McNally, R. J. (2001). On Wakefield’s harmful dysfunction analysis of mental disorder. Behaviour Research and Therapy, 39, 309–314. McNally, R. J. (in press). The cognitive psychology of repressed and recovered memories of childhood sexual abuse: Clinical implications. Psychiatric Annals. McNally, R. J., Clancy, S. A., & Schacter, D. L. (2001). Directed forgetting of trauma cues in adults reporting repressed or recovered memories of childhood sexual abuse. Journal of Abnormal Psychology, 110, 151–156. McNally, R. J., Clancy, S. A., Schacter, D. L., & Pitman, R. K. (2000a). Personality profiles, dissociation, and absorption in women reporting repressed, recovered, or continuous memories of childhood sexual abuse. Journal of Consulting and Clinical Psychology, 68, 1033–1037. McNally, R. J., Clancy, S. A., Schacter, D. L., & Pitman, R. K. (2000b). Cognitive processing of trauma cues in adults reporting repressed, recovered, or continuous memories of childhood sexual abuse. Journal of Abnormal Psychology, 109, 355–359. McNally, R. J., & Steketee, G. S. (1985). The etiology and maintenance of severe animal phobias. Behaviour Research and Therapy, 23, 431–435. Mineka, S., & Zinbarg, R. (1996). Conditioning and ethological models of anxiety disorders: Stress-in-dynamic-context anxiety models. Nebraska Symposium on Motivation, 43, 135–210. ¨ st, L.-G., & Hugdahl, K. (1983). Acquisition of agoraphobia, mode of onset and anxiety response patterns. Behaviour O Research and Therapy, 21, 623–631. Papini, M. R., & Bitterman, M. E. (1990). The role of contingency in classical conditioning. Psychological Review, 97, 396–403. Poulton, R., & Menzies, R. G. (in press). Non-associative fear acquisition: A review of the evidence from retrospective and longitudinal research. Behaviour Research and Therapy. Wolpe, J., & Rachman, S. (1960). Psychoanalytic “evidence”: A critique based on Freud’s case of Little Hans. Journal of Nervous and Mental Disease, 131, 135–148.