David Navon (1994) From Pink Elephants to Psychosomatic Disorders:. Psycoloquy: 5(36) Paradoxical Cognition (1)

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Psycoloquy 5(36): From Pink Elephants to Psychosomatic Disorders:

Target Article by Navon on Paradoxical Cognition

David Navon
Department of Psychology
The University of Haifa
Haifa, Israel



Several paradoxical effects in cognition are discussed. One type is "evasions" -- of a thought, a perception, or a response -- that may cause the presence of precisely what is meant to be avoided. Another type is "lay interventions" that channel information to mental processes that do not know how to deal with it, often resulting in aggravation of the problem meant to be solved by the intervention. Some psychosomatic effects may be due to lay interventions. Paradoxical effects may stem from attempts to bypass, or substitute for, the normal functioning of subsystems of the mind.


attention, automatic processes, consciousness, controlled processing, incidental learning, motor set, pain, panic attacks, paradoxical effects, positive feedback, psychosomatic disorders, recall failures
        A dervish taught a Bedouine how to make gold out 
        of straw: Put the straw in boiling water and stir 
        it for three hours; but remember, while stirring 
        don't ever think of a pink elephant...
                                 (from a Bedouine folktale)

        Seek not and ye shall find.
            (from the title of Johnston & McClelland, 1974)

1. Any effect that is produced or strengthened by something that is meant to avoid or reduce it may be called a "paradoxical effect." In the following, I discuss several phenomena that might be considered paradoxical effects in cognition [NOTE #1]. Such effects are admittedly rare; they are by definition maladaptive, and a species, to survive in its environment, would be better off without a high frequency of them. This, however, is also true of perceptual illusions and irrational decisions. In its domain, each must be the exception rather than the rule. Psychologists are interested in such anomalies because they may reveal a good deal about the systems which control such mental functions. My interest in paradoxical effects is likewise mainly motivated by the light they might shed on how the mind works.

2. I focus on phenomena that, rare as they may be, seem to be real for normal people. As will be seen, however, certain pathologies are perhaps characterized by proliferation or intensification of those phenomena.

3. In the case of some of the phenomena addressed here, their paradoxical nature is self evident. In the case of some others, their interpretation as paradoxical is novel. What is most important is that several simple features appear to be shared by a number of psychological phenomena from various domains, suggesting the possibility of an underlying unifying principle.



4. One paradoxical effect in cognition is what might be called "cognitive evasion": intentional attempts to refrain from thinking of something, say, a pink elephant, often backfire (e.g., Wegner & Erber, 1992; Wegner, Erber & Zanakos, 1993; Wegner, Schneider, Carter & White, 1987). The reason seems straightforward.

5. Attention is to a considerable extent determined by activations generated automatically by stimuli (Berlyne, 1970; James, 1981/1890; Titchener, 1903). It is likely to be drawn to an object to the extent that the latter is related to some unsatisfied need. It is also likely to be drawn to context-relevant objects (Deutch & Deutch, 1963; Norman, 1968; Treisman, 1969). The simplest criterion for context relevance is recent activation. Now, any deliberate attempt to refrain from thinking about something must address the to-be-avoided concept. That, of course, necessarily activates that concept. The activation may be especially high because of the relevance of the attempt itself to the need or because of the anxiety associated with the fear of failure. The rest follows in a straightforward way.

6. Of course, with some effort, the to-be-avoided object can be kept away from focal attention. Its mandatory activation, or its presence in peripheral attention, however, hampers the ability to meet the goal of banning that object from focal attention. The spread of activation (Collins & Loftus, 1975) to related concepts complicates the problem because it primes a set of potential triggers for revived activation. Furthermore, as with every goal deemed important, one occasionally stops to review its success. Unlike with every other goal, however, in this case the review itself ("How nice! For ten minutes I haven't been thinking of pink elephants.") entails failure. Even when the goal is successfully met for a while, there seems to be a rebound effect, namely, greater-than-usual attention to the to-be-avoided object after the inhibition is relieved (e.g., Freud, 1914 & 1958; Lavie & van den Hout, 1990; Wegner, Schneider, Carter & White, 1987; but see also, Clark, Winton & Thynn, 1993); enhancement of sympathetic arousal has also been observed (Wegner, Shortt, Blake & Michelle, 1990). These findings suggest that the activation itself is not avoided; rather, during the inhibition period it waits for its processing. What has been put on the agenda may be pushed downwards in the queue but is probably hard to remove (cf. Navon, 1989a, for a general discussion of attention agenda). Alternatively, the activation may facilitate a later activation in response to the right prompt, which may result in focal attention to the object at that time. An alternative account by Wegner (1994) is discussed in paragraph 16, below.


7. Closely akin to cognitive evasion is perceptual evasion. Focused attention is often successful, provided that the selection cue is both separable from the response dimension (Garner, 1974) and efficient for selection (Duncan, 1981). Despite evidence that rejected stimuli may be processed to some degree (e.g., Allport, Tipper & Chmiel, 1985; Duncan, 1980; review in Holender, 1986; Johnston & Dark, 1986), the fact remains that these stimuli are not available for report. However, one can intentionally attempt NOT to perceive something in the attended region or object, for example, a dimple on a face that is being focally attended. Such an attempt is likely to fail (James, 1981/1890, p. 419; Kahneman & Treisman, 1984). The reason is probably that perception is to a great extent conceptually driven (e.g., Broadbent, 1977; Mandler & Parker, 1976; Norman & Bobrow, 1976; Palmer, 1975; Schvaneveldt & Meyer, 1973). This does not mean that perception depends on volition, but rather that expecting a stimulus is sufficient to initiate processes which regularly terminate in perceiving it, if it is present. An intention to avoid perceiving something clearly activates its representation, which may be enough to initiate those perceptual processes. Thus, paradoxically, a stimulus embedded within an attended channel has a significant chance of being overlooked only if there is no deliberate intention to ignore it.

8. Failures of selective attention, like the famous Stroop effect (Dyer, 1973; Logan, 1980; Stroop, 1935), as well as other similar effects (Eriksen & Hoffman, 1973; Lupker & Katz, 1981; Morton, 1969; Navon, 1977, 1991; Palef & Olson, 1975), may be regarded as further instances of perceptual evasion. The Stroop effect is often considered a demonstration of automatic processing (e.g., Posner & Snyder, 1975; Shiffrin & Schneider, 1977; but see Kahneman & Chajczyk, 1983; Kahneman & Henik, 1981; Yee & Hunt, 1991). Another account is that the verbal responses trigger the perception of the aspect that in the natural environment is the most likely to give rise to them (Johnston & Dark, 1982, 1986; Kahneman & Treisman, 1984; Neisser, 1976; Neumann, 1984), for reasons that are similar to the ones mentioned in the preceding paragraph, namely, conceptually driven perception. Perhaps, however, the explanation has to do, at least in part, with perceptual evasion. The evident need to ignore the meaning of a word in order to be able to respond properly to some physical attribute that correlates with that meaning may lead to an attempt to avoid the meaning. That may be sufficient to set off the cycle that ends in perceiving that meaning. This interpretation is supported by the finding that under mental load the Stroop effect is increased for to-be-suppressed target words (Wegner, Erber & Zanakos, 1993).

9. Trying to avoid a familiar interpretation of an ambiguous figure may be doomed to a similar fate. The perceptual interpretation of ambiguous figures tends to alternate over time; it is for this reason that they are called reversible or multistable. Since both interpretations are primed, why would the one which benefits from current activation be superseded by the other? A popular explanation is that the former is inhibited by neural fatigue (e.g., Kohler & Wallach, 1944; Nawrot & Blake, 1989). Perceivers who do not know that a particular figure is ambiguous, however, often do not spontaneously notice the ambiguity and do not experience reversal (Girgus, Rock & Egatz, 1977). It seems puzzling that neural fatigue is not very effective when only one interpretation is known. Perhaps the reason is that what is fatigued is simply the inhibition of a known interpretation, an inhibition exerted in order to maintain the other interpretation. Since the former is primed by the intention to avoid it, one cannot help perceiving it sooner or later. A result indicating that this might be so was recently reported by Long, Toppino and Mondin (1992). Short preexposures of an unambiguous version of an ambiguous figure biased perception in its favor when preexposure was short, but in the opposite direction when preexposure was long. In the latter case, the effect of the prime may conceivably have been mediated by an intentional inhibition (one known to require some time to have an effect) (see Neely, 1976; Posner & Snyder, 1975) of the alternate interpretation; in view of the high availability of the latter, such an inhibition is likely to fail.


10. If perceptual and cognitive evasions are at times paradoxical, might not response evasion be paradoxical as well? On the one hand, it is a fact that we can inhibit our responses better than our perceptions and thoughts (see Logan, 1985). Not all of our responses are entirely under the voluntary control of our central nervous systems, however, and even those which are may be differentially inhibitable. Hence, our body as a whole might respond to a cognitive event despite our deliberate attempt to withhold an overt response, and perhaps that response would be strengthened by our attempt to suppress it. How can this happen?

11. It is reasonable to suppose that our potential actions are governed by concepts and schemata just as our perceptions and thoughts are (MacKay, 1987; Norman & Shallice, 1985). An action schema may be activated without any deliberate intention. Since several activated schemata often compete for selection, the activation of an action schema cannot automatically lead to an overt response. However, activation increases the likelihood that the response will be emitted, even when inappropriate (e.g., Baars, Motley & MacKay, 1975; Norman, 1981; Reason, 1984; Sellen & Norman, 1992). A considerable proportion of observed action slips fall into this category (called "capture errors" by Norman or "intrusions" by Reason). The reason is presumably that attention is not always available to censor inappropriate responses. Alternatively, attention may not even have the power to censor, only to bias selection (Norman & Shallice, 1985). More important, the activation conceivably gives rise, at least in part, to outcomes that are concomitants of the critical motor response. For example, suppose a certain action, A, manifests a certain motor response, R, and is typically accompanied by sympathetic activity, S, and a change of posture, P. The activation thresholds for S and P must be lower than the threshold for R, presumably because the former are frequently antecedent conditions for the latter. In addition, the mechanism that inhibits R may not be designed for inhibiting S and P as well. Thus, activating the schema of A may trigger S and P even when R is not executed.

12. Now, just as the intention to refrain from thinking some thought, or perceiving some stimulus, in itself activates the to-be-avoided concept, so the intention to refrain from some action may be sufficient to activate the corresponding action schema. By and large, the efficient inhibitory mechanisms in the response system would block the execution of the overt response, yet sometimes the activation of the action schema leads to subtle manifestations of the response (e.g., Easton & Shor, 1976; Wegner & Anisfeld, cited in Wegner, 1994). More frequent, presumably, are concomitant effects on the body. Furthermore, it appears that the more molecular the response, the higher the chance that its inhibition will fail.

13. Experimental evidence of such failures of response evasion is scarce, but some reflection might reveal that anecdotal evidence does exist: for example, tell a kid not to sniff at dinner, or better yet, tell him not to giggle during a sermon. Adults typically have better self-restraint, but I suspect any one of us can recall some cases when we either failed to comply, or at least had trouble suppressing the tendency to act, which could already have affected the autonomous system. In another vein, the ability to swim under water seems to be considerably reduced by actively thinking of the need to hold one's breath, that is to evade inhaling. Another example is trying to balance oneself or an object, say, a full bowl of hot soup. Fearing an unfortunate tremor or jitter sometimes acts like a self-fulfilling prophesy. It must be the intentional attempt to avoid those responses which causes the problem, because often when the person is unaware of or oblivious to the risk, he performs much better. To be a little more convinced, tell a person to walk within a 30 cm stripe drawn on the floor, then tell him to walk on a 30 cm wide beam at a considerable height. A sober person must be able to perform the former task perfectly, yet would probably manifest difficulties in the latter one.

14. Indeed, such responses are not ones for which we have the greatest control. Consider, then, a person who is trying to pretend not to see an approaching person he does not want to meet at the moment. Sometimes his oculomotor system will embarrassingly betray him. At other times, he might feel a sympathetic arousal that is reminiscent of the one resulting from an actual encounter [NOTE #2].


15. The phenomena discussed are obviously not universal, and presumably not even frequent for most people [NOTE #3]. Their occurrence seems to be restricted to, or pronounced under, certain circumstances, probably some preoccupation, absent-mindedness, stress, load, or loose voluntary control (see review in Wegner, 1994). The reason is simple: voluntary attention and selectivity require effort (cf. James, 1981/1890; Johnston & Dark, 1986; Johnston & Heinz, 1978; Kahneman, 1973), and effort is less available or less efficiently applied under load, stress, etc.

16. Wegner (1994) recently presented a theory to explain a number of paradoxical effects I would call evasions. He suggested that mental control involves two processes: an intentional operating process that searches for desired mental contents, and an automatic monitoring process that searches for mental contents which signal a failure of the operating process and increases their activation, so that the operating process can operate on them. The monitoring process is paradoxical ("ironical," in Wegner's terminology), because its sensitivity to unwanted mental contents increases the likelihood of their surfacing in consciousness. Normally, the operating process counteracts that. However, under conditions of load, it often fails.

17. In my view, the notion of a monitoring process that increases the activation of unwanted contents is both functionally implausible and theoretically gratuitous. Any guarding mechanism requires a danger detector, yet detection is necessary for guarding against the danger, certainly not for yielding to it. A cleverly designed mechanism would keep the output of the detector out of the guarded domain. It is hard to believe that God or evolution were not that clever. More important, as suggested above, the attempt to evade creates the danger in the first place. When that danger is increased by mental context and not met by enough guarding effort, it is more likely to materialize. Thus, it seems more parsimonious to conceive of paradoxical effects as failures in operation than as flaws in design.

18. Is load always fatal for evasion? To the extent that the load is independent of the process by which evasion is effectuated, the former reduces the amount of effort that can be devoted to the latter. This must be the case, for example, when subjects are asked to rehearse six digit numbers or to count backwards (Wegner, 1994). However, load might sometimes be beneficial. The modulating factor is interest, a factor known at least since James (1890) to be the primary determinant of concentration. One should expect absorption in an interesting task to help evasion as long as interest is maintained. The Achilles' heel is presumably the moments when attention allocation is reconsidered. Whatever is on the agenda might be reviewed then, including the to-be-avoided subject. This might be precipitated by stress, for reasons that have nothing to do with load. Anxiety-provoking stimuli may tend to be spontaneously avoided (see review in Eysenck, 1982), thereby leading to a review of the attentional agenda.

19. The three types of evasion discussed above share the following structure: they cause activation of the to-be-avoided mental representation; they cause inhibition to be exerted; and yet, the activation itself might nevertheless result in some outcome.

20. Furthermore, in the case of evasion, the activation is conceptually driven. That may call for the intervention of controlled processes. And that, in turn, may be the source of another problem, one that is elaborated in the next section.


21. Other types of paradoxical effects have to do with what might be called "lay intervention." We are all familiar with the potential harm of having an inexperienced person perform an assignment that calls for an expert. The same may be true of mental processes.

22. Perfecting skills takes an enormous amount of practice, sometimes years of it (Fitts & Posner, 1967). It is widely believed that skilled performance is accomplished through automatic processes (e.g., Logan, 1988, 1989; Norman & Shallice, 1985; Schneider, 1985; Shiffrin & Schneider, 1977). Most of what we do in the real world involves applying some skills. Even when we create novel structures, say, an original phrase, we cannot help resorting to some well-practiced, possibly automatic processes.

23. Sometimes an intervention is imposed, however. It usually results from the monitoring of the activity by the person himself or by someone else, leading to the decision to modify some element or to try harder. But that, of course, cannot be done automatically. A controlled process must take over. Alas, often the attempt to correct ends up in deterioration. The reasons may be quite straightforward: the controlled process does not have the benefit of years of practice. Due to limits on structures used by it, such as working memory, the controlled process uses awkward techniques, such as serial search. Furthermore, since the information embodied in the automatic process is probably encapsulated, it cannot be accessed, let alone used, by the controlled process. A possible gain in internal insight is therefore offset by a high loss in efficiency.

24. Sometimes, when the automatic process runs into an insurmountable problem, the intervention of a controlled process is the lesser evil. The controlled process might help, provided it has access to more information and ways of reacting to that information. For example, if one realizes what was wrong with the way one mistyped a word, one might simply start over or retrieve orthographic information from the appropriate store. Sometimes, however, the controlled process cannot do much better than a shot in the dark.


25. Consider, for example, the case of failing to recall a name - a fairly frequent failure according to Reason (1984). It presumably occurs when the contextual cues lead the automatic process astray, or when the retrieval of closely related but erroneous information blocks the retrieval of the target information (Jones, 1989; Roediger & Neely, 1982; but see Perfect & Hanley, 1992), or when some critical communication channels are blocked at the time the recall attempt occurs (Navon, 1989a). The person who fails to recall often "tries harder" (Brown & McNeill, 1966; Flavell & Wellman, 1977). This presumably amounts to initiating a controlled process, one that often has neither better retrieval cues nor an efficient search algorithm (see Hasher & Zacks, 1979; Posner & Snyder, 1975; Shiffrin & Schneider, 1977). Worse yet, it probably reconstructs the to-be-remembered item, perhaps refabricating, filling in missing parts through inference or imagination, rather than retrieving them (Bartlett, 1932; Loftus & Palmer, 1974; Norman, 1970; Williams & Santos-Williams, 1980). Indeed, anecdotal evidence suggests that such controlled processes often fail, at least in the short range (e.g., Norman & Bobrow, 1976).

26. Clearly, that an attempt to attain some goal is successful only partly or occasionally does not in itself entail that the attempt is useless, let alone harmful. However, a controlled process may not only have limited efficacy; it may also interfere with the automatic process specialized for the purpose (Kimble & Perlmuter, 1970; Reason, 1984). Automatic processes are frequently asserted to be immune to any kind of interference (Hasher & Zacks, 1979; Logan, 1980; Posner, 1978). Nonetheless, that is not always the case with processes that seem to be automatic by other criteria (Bargh, 1992; Kahneman & Treisman, 1984; Paap & Ogden, 1981; Regan, 1981). Although an automatic process may not consume processing resources nor be subject to the same sorts of outcome conflicts (Hirst & Kalmar, 1987; Navon, 1985; Navon & Miller, 1987) from which controlled processes may suffer, it might depend on the satisfaction of some global conditions within the processing environment. For example, it was proposed by Navon (1989a, 1989b) that attentional processing requires blocking or attenuation of most communication channels in the processing system. That state may be detrimental for automatic processes, such as searching by spreading activation or conjoining previously unassociated concepts in the course of problem solving or creative activities. Such processes may be performed better in a state of relaxation in which communication channels are open. Thus, the effortful mode adopted for the sake of "trying harder" may preclude satisfaction of the conditions that are optimal for the execution of the corresponding automatic process [NOTE #4]. Sometimes, upon return to a relaxed mode or after attention has been extensively engaged by other activities, the goal is suddenly attained, for example, a searched-for name or solution may pop up suddenly or be retrieved readily when needed (Dominowski & Jenrick, 1972; Glucksberg & Weisberg, 1966; Judson, Cofer & Gelfand, 1956; Norman & Bobrow, 1976; Olton, 1979; Patrick, 1986; Smith & Blankenship, 1989; Yaniv & Meyer, 1987). The automatic process has presumably taken over. This phenomenon is conventionally called incubation, a name implying a prevalent conjecture that some latent activity is performed during the period between the failure and the success. According to another account, time is needed for forgetting the information on which the subject has fixated and which has blocked a successful retrieval (Smith & Blankenship, 1989). That the length of the period is critical has not been adequately substantiated, however. A release from effortful search may be sufficient. Some hint in that direction is a report that the effect occurred only when the problem was interrupted by an unrelated, relatively easy, activity (Patrick, 1986).

27. Furthermore, performance failures typically provoke some anxiety, whose degree depends on the person, the severity of the failure, and previous occurrences of failures of that sort (e.g., Mandler, 1989). As elaborated below, an increase in the level of anxiety arouses the system, thereby disposing it towards effortful processing (Navon, 1989b). The temporary difficulty in relaxing makes it even less likely that the relevant automatic process will return to the fore and allow successful recall.


28. Another area where lay intervention effects have been documented is motor behavior. Skilled motor performance involves intricate scheduling and coordination shaped in the course of numerous trials. Thus it is probably governed by automatic motor programs (Bernstein, 1967; Brooks, 1979; Keele, 1968; Kelso & Stelmach, 1976; McLeod, McLaughlin & Nimmo-Smith, 1985), presumably sensitive to peripheral feedback (Adams, 1971; Marteniuk & MacKenzie, 1980). Ample evidence for the automatic nature of skilled motor activities dates back to the turn of the century (Bryan & Harter, 1896; Solomon & Stein, 1896). Attempting to consciously control such performance may introduce top-down activations that are suboptimal, having not been calibrated by experience (Henry & Rogers, 1960). It has been demonstrated that even just attending to a motor activity may interfere with it (Christina, 1973; Henry, 1960; Henry & Rogers, 1960; Krahenbuhl, Plummer & Gaintner, 1975). Specifically, latency as well as movement time may increase when the performer attends to the movement rather than to the stimulus which is supposed to release it. In a similar vein, it has been reported that endurance athletes perform worse and complain more of expended effort, fatigue, and physical symptoms, when instructed to pay attention to their bodily operations (Padgett & Hill, 1989; Pennebaker & Lightner, 1980). Whereas this may be due to the greater distraction from pain afforded by other attention strategies, it may also be, at least in part, due to the unwelcome intervention of attention in motor or respiratory activity.


29. An effort to learn may also have a paradoxical effect. Some learning may occur implicitly, without any deliberate intention. That includes, for example, capturing environmental probabilities, such as covariation between stimuli (Green & Flowers, 1991; Lewicki, 1986; Lewicki, Hill & Bizot, 1988; Nissen & Bullemer, 1987; Reber & Millward, 1971), encoding spatial location (Schulman, 1973) or frequencies (Naveh-Benjamin & Jonides, 1986), and even learning rules, such as those governing artificial languages (Broadbent, FitzGerald & Broadbent, 1986; Mathews, Buss, Stanley, Blanchard-Fields, Cho & Bruhan, 1989; Reber, 1976, 1989). The interesting finding in many of these studies is that explicit verbal instructions impair learning. For example, the instruction to attend to the location of a word resulted in recognition and recall that were poorer than those obtained in conditions of incidental learning (Schulman, 1973). Explicit strategies presumably act to direct attention to properties that contribute little to acquisition. This may lead to reduction in the amount of attention directed to more useful information or even to the inhibition of automatic procedures of encoding and inference.


30. A well-documented phenomenon that appears paradoxical is the effect of high motivation on performance (see review in Eysenck, 1982). This effect has been studied extensively, especially in sport contests and test taking. For example, factors that affect the drive to succeed, namely, audience, competition, performance-contingent reinforcement, and ego relevance, often cause failure (Baumeister & Showers, 1986). Of course, incentive affects arousal, which has long been known to have a curvilinear effect on performance (Yerkes & Dodson, 1908). However, what is sometimes called the Yerkes-Dodson law is a generalization of empirical phenomena rather than a theory. The descending portion of the Yerkes-Dodson curve is commonly explained in terms of attentional mechanisms. For example, it has been proposed that higher arousal leads to restriction of the range of cues examined by the performer, and especially high arousal makes him ignore some relevant cues (Easterbrook, 1959). Another possibility is that while highly aroused, the performer allocates much attention to worry, which detracts from the amount of attention available to goal-pertinent processing (Eysenck, 1982; Wine, 1971).

31. More important for our concern, when the arousing factor is incentive, the decrement in performance might be caused by lay interventions, namely, by attempts to apply a controlled process that does more harm than good. To illustrate, a basketball player who is eager to succeed in a free throw may try to program on the fly an algorithm that deviates from the automatic one shaped during numerous throws. Since an integrated motor pattern naturally precludes any alternative one, the controlled effort would suppress the execution of the optimal pattern governed by the automatic process (Baumeister, 1984). Alternatively, self awareness induced by high incentive may slow down processing simply because the controlled process considers a number of options, instead of the single one exerted by an automatic process (Carver & Scheier, 1981). Baumeister and Showers (1986) conclude that existing evidence leaves the latter explanations, as well as the distraction model, as the preferred accounts of incentive- induced failures.


32. Many investigators of attention believe that perception of familiar stimuli is accomplished by automatic processes (e.g., Deutch & Deutch, 1963; Duncan, 1980; Norman, 1968; Schneider & Shiffrin, 1977). The numerous cases in which attention has been found to facilitate perceptual discrimination (e.g., Eriksen & Hoffman, 1973; Johnston & Dark, 1982; Jonides, 1981; Kahneman, Treisman & Burkell, 1983; Posner, 1980; Posner, Davidson & Snyder, 1980) are accounted for by those investigators in terms of the effect of attention on post-perceptual stages. Even those researchers who propose that perception requires attention (e.g., Broadbent, 1958, 1971: Johnston & Dark, 1986; Treisman, 1969, 1985) typically assume that many simple functions of perception are processed automatically. What happens when attention is directed to a feature that is habitually processed by automatic processes? Several phenomena can be interpreted to indicate that attention could be harmful in that case.

33. Letter discrimination is more accurate when the letters are embedded in words than when the letters are embedded in nonwords or presented in isolation, even when any guessing advantage for words is eliminated (Johnston & McClelland, 1973; Reicher, 1969; Wheeler, 1970). Similarly, letters within words are less accurately discriminated when attention is focused at them rather than at the whole word (Johnston & McClelland, 1974). These word superiority effects seem to depend on sensory factors such as type of masking (e.g., Jordan & de Bruijn, 1993; Purcell & Stanovich, 1982; but see Marchetti & Mewhort, 1986 and Prinzmetal, 1992). Their usual explanations (e.g., Johnston, 1981; McClelland & Rumelhart, 1981) do not make much use of the concept of attention. However, the underlying principle may be straightforward: letter processing conducted automatically during word recognition must be habitual and efficient. Letter processing in any other context is less habitual, and an attempt to import attention may cause lay intervention. A similar effect, known as object superiority or configural superiority, has been reported in other domains of perception (Davidoff & Donnelly, 1990; Lanze, Weisstein & Harris, 1982; Pomerantz, Sager & Stoever, 1977; Weisstein & Harris, 1974; Womersley, 1977). Again, whatever the correct explanation is, it may well be consonant with the following claim: attention to features imposes a lay intervention on automatic processes that are normally subordinated to the perception of the wholes to which the features belong.


34. A particularly interesting lay intervention concerns the mechanisms governing attention itself. The direction of attention is determined both by autonomous factors and voluntary control (Berlyne, 1970; James, 1981/1890; Jonides, 1981; Kahneman, 1973; Navon & Gopher, 1979; Posner, 1978; Shiffrin & Schneider, 1977; Titchener, 1903). Unlike other controlled processes discussed above, the controlled processes which mediate voluntary direction of attention generally have the benefit of long practice. On the other hand, they are sometimes less potent than the autonomous triggers of attention. This typically happens when the object being focused on does not have enough potential intrinsic interest, or when the subject has not yet discovered it. Interest is probably the stronger determinant of attention (James, 1981/1890). In such cases, an effortful attempt to win the battle for attention may sometimes turn out to have paradoxical effects (Wegner & Erber, 1991, cited in Wegner, 1994).

35. This may happen when the effort is invested in the inhibition of unwanted candidates for attention. To the extent that this involves momentary shifts of attention towards the act of inhibition - or worse yet towards the to-be-inhibited objects - the continuity of attention towards the to-be-focused object may be threatened. The result is greater difficulty in processing that object (Allport, 1980), hence a smaller chance of discovering intrinsic interest in it to secure a sufficient amount of attention to it later on. Losing concentration may quickly turn into a snowball effect, especially when the pace of information arriving from the to-be-focused object cannot be controlled by the subject (e.g., during a talk). Another result of excess emphasis on inhibition is that beyond a certain point in processing, it becomes simply an attempt at cognitive, or perceptual, evasion. The paradoxical effects of such evasions have been discussed above. This mode of concentration may be classed as lay intervention, because it interferes with the natural and more effective way of concentrating, which presumably amounts to getting progressively involved with the to-be-focused object.


36. Especially important lay interventions are those that interfere with sensorimotor processes controlling very habitual functions such as locomotion or vital functions such as breathing. Such processes must basically be negative-feedback, self-correcting systems that are adaptive for maintaining optima or homeostases within their domains (Adams, 1971). Their optimal functioning might be partly innate but elaborated through extensive trial-and-error over very long periods (see, e.g., Ballard, 1986; Grossberg, 1980; Rumelhart, McClelland & the PDP Research Group, 1986; Rumelhart & Zipser, 1985; Seidenberg & McClelland, 1989; Sejnowsky & Rosenberg, 1986). The two endemic problems with systems of that sort are (a) they might be absorbed in local minima, and (b) they converge to the equilibrium only within a certain range of deviation. A grave error in diagnosing a present state may throw the process into a range where it might be absorbed in a local minimum, or worse yet, might start to diverge, namely, to get further and further off the equilibrium.

37. It is quite clear that such systems are modular (in the sense of Fodor, 1985), in that their components are automatic and encapsulated (i.e., cognitively opaque, excluding perhaps the most molar level). Any percept, veridical as it may be, that is derived from sources that are exogenous to the system, cannot be responded to by the motor components trained to respond only to endogenous sensory sources. Likewise, any motor response initiated exogenously cannot provide the type of feedback that the endogenous sensory components recognize. For example, the respiratory center in the medulla oblongata reacts mainly to input from afferent neurons originating in receptors of CO2 concentration in the arteries. Thus, a cognition of present or imminent shortage of oxygen in the body - probably formed somewhere in the cortex - cannot be operated on by the breathing module, and must be responded to by a voluntary inhaling response.

38. That lay intervention could be inappropriate in diagnosis, remediation, or both. The perceived deviation, to the extent that it reflects a real deviation at all, may be one that falls well below the optimal response threshold (as in the case of underwater swimming, mentioned above), and the response may be a gross overshot. In any event, the intervention might act to throw the respiratory system into a range where the breathing module is either absorbed in a local minimum or starts to diverge. This unusual state might, in turn, cause further interventions that might be even less appropriate. The consequence is a snowball effect that may be quite harmful, at least from a mental point of view. For example, it might end in a state of hyperventilation. This is not a wild speculation. One of the symptoms of what psychiatrists call panic disorders involves psychogenic, or psychologically mediated, breathing difficulties (e.g., McNally, 1990; Walker, Norton & Ross, 1990; Zal, 1990).

39. Now, how are "lay" cognitions of this type formed? I suggest they result from attention being drawn to a sensory surface that is regularly accessed only by the pertinent modules. Indeed, it has been found that more symptoms of disorder are reported when attention is drawn to related bodily sensations (Pennebaker, 1982).

40. This may happen, for example, during situations with little sensory input. It may also happen as a result of some explicit message, such as when one is instructed or induced to direct attention to that surface. People may somehow acquire a habit of occasionally attending, often involuntarily, to that surface. Some mental pathologies, such as attention deficit disorders or schizophrenia, are characterized by constant or frequent attentional shifts to surfaces that are normally unattended (Barkley, 1990; McGhie, 1969).

41. Another avenue by which attention to a sensory surface may be brought about is perception of related events in other surfaces or modalities. For example, because yawning is a response to shortage of oxygen, the sight of someone else yawning might trigger, by way of association, an automatic shift of attention to the present state of oxygen (surely too brief to be consciously available in most circumstances). As claimed above, a system that is exogenous to the breathing module might have no idea about the level of oxygen that requires correction by inhaling or exhaling. Thus, attention to the state of oxygen may lead the perceiver himself to yawn, which might hamper the balance between oxygen and CO2. By the same token, when the homeothermal system is bypassed by some lay intervention, such as overattention to sensed temperature, the autonomous responses that ensue may be counterproductive.

42. Finally, a nonhabitual state within a sensory surface may attract attention. For example, people sometimes hold their breath unconsciously for quite a long period under some conditions (e.g., Nikandrov & Blinkov, 1983; for a description of pathological breath holding, see Vachon, 1989). Hypopnea (breathing less than one should) is even more prevalent. When suddenly detected, this deviation from the optimal level invokes attention. The consequence may be the initiation of a lay process that may often fail to solve the problem.

43. These effects may be negligible by and large, but they may sometimes open the gate to snowball effects. Presumably, the more salient the triggering event, the stronger these effects can be. For example, in mass hysteria, people are overwhelmingly exposed to the sight of other people manifesting some symptoms (Colligan, Pennebaker, & Murphy, 1982). It has been reported by Small, Propper, Randolph and Eth (1991) that in such a situation, the best predictor of the development of symptoms was observing a friend become sick.

44. People prone to such effects may try to avoid them by evading their triggers or by inhibiting the attraction of attention towards those triggers. Because such attempts are instances of cognitive evasion, they may fail from time to time. Failures must be more likely under the conditions that typically elude evasion, namely, those that lead to the loosening of selectivity. Load and stress certainly do so (McNally, 1990), because they curtail the ability to recruit the necessary effort. Interestingly, relaxation attempts may have a similar effect (see review in Wegner, 1994). The reason is maybe that relaxation disengages mental resources, removes inhibition, triggers a review of attention agenda, or all of these.


45. An activity - if it may be so called - that may be particularly sensitive to lay intervention is falling asleep (Wegner, Anisfeld & Bowser, cited in Wegner, 1994; for a review, see Mendelson, 1987). This is taken care of by processes that are as cognitively opaque as can be. More important, a frequent reaction to difficulties in falling asleep is "trying harder." Since most people do not have the faintest idea of what to do about it, they initiate some controlled processes that grope in the dark and naturally give rise to an increase in arousal. Some intentional tricks that are said to be helpful when the difficulty is moderate, such as counting sheep, may prove inept when the state of sleeplessness is severe, let alone in the case of chronic insomnia. Even when one knows that one must somehow get less aroused, one rarely knows exactly how to do this. A wrong decision about posture, muscle tonus, breathing, or train of thought may set off a vicious circle of the type described above. Since sleep probably depends on all of these variables, the probability that no wrong decision will be made about any of them is particularly small. Worse yet, the likelihood of any one wrong decision is probably greater in this case, because the personal theories of most people about sleep, which is a change in state of consciousness, must be less accurate than their common sense view of respiration, locomotion, etc. Sleepless people are commonly, and quite appropriately, warned against doing any of the things mentioned here. Sometimes they are even encouraged to stay awake (Ascher & Efran, 1978). What that advice boils down to is letting the automatic processes regain control.


46. Lay interventions may be more likely when the person is anxious or overaroused for some other reason. Overarousal tends to make attention more labile (see, e.g., Eysenck, 1982, for a review), and the high likelihood of distraction motivates the system to exert stringent selection by blocking communication channels (Navon, 1989b). This hampers the conditions required for efficient automatic processing, which in turn forces the intervention of lay controlled processes.

47. If anxiety indeed acts to dispose the system toward lay interventions, the self-strengthening nature of the process of lay intervention can easily be accounted for. The harmful consequence increases the anxiety, and thereby makes the chance slimmer that the efficient automatic process returns to take the lead. Furthermore, when the level of anxiety becomes particularly high, protection from distractions is very difficult, and the occurrence of a distraction may substantially diminish the quality of the output, which becomes a cause of further anxiety, and so forth. A snowball effect (destructive positive feedback) is under way.


48. It may be contended that some intentionally initiated interventions do succeed. My answer is that a controlled process is not inherently paradoxical. It is paradoxical when it does not have the pertinent information. A properly guided training of self-regulation, however, such as biofeedback (e.g., Schwartz & Beatty, 1977; Yates, 1980) or various meditation and relaxation techniques (Ornstein, 1972), may give controlled processes access to information they do not regularly have. It may also desensitize the person to the effects of failure or its anticipation, thereby establishing recovery that is sufficiently fast to prevent escalation.

49. The conventional association between control and consciousness might make one wonder how consciousness can help where automatic processing would be ideal. The problem with most controlled interventions, however, is not so much that they involve attention, but rather that they are lay interventions (i.e., nonexpert). Consciousness of the appropriate processes may help by providing pertinent information. For example, when the triggering condition is an involuntary shift of attention to a sensory surface that would rather be unattended, self-consciousness may enable one to either inhibit that shift in advance or to make an intentional shift away from that surface and in the proper direction. This could occasionally fail, as could any evasion, but on the whole it might be beneficial.

50. In sum, lay interventions channel information to mental processes that do not know how to deal with it and, in addition, interfere with the proper execution of processes that do.


51. What evasions and lay interventions have in common is that they both have paradoxical effects. On the other hand, they appear to have opposite directions: evasions are attempts to avoid attention, whereas lay interventions are attempts to usurp control through attentional processes.

52. Yet, evasions and lay interventions may be intimately related. All evasions share the property that they are meant to prevent a likely psychological event. The to-be-prevented events are likely because they are generated by processes which are triggered by input information. Those processes must be automatic, by and large. Thus, an attempt to prevent the natural consequences of such a process calls for inhibiting, or substituting it with another process. Since the latter is not triggered by input information, it is most plausibly controlled and unhabitual. Hence, the intention to evade leads to the intervention of a lay process that interferes with the activity of an automatic one.

53. For example, an effort not to spill soup from a bowl may lead to the activation of controlled motor processes that are suboptimal for the cause. An attempt to avoid the sight of an approaching person may involve a pattern of activity of the eyes, the head, and the body, that is quite unnatural. An attempt to evade a thought may lead one to apply unusual inhibitory measures that may interfere with the natural course of events in the mind or in the body at large. The consequence is that even when evasion is successful, it presumably induces a chain of events that may be undesirable, and may even result in a snowball effect.


54. By "psychosomatic effect," I mean any phenomenon that is conventionally regarded as organic and has some real basis but is accentuated by cognitive factors. It is not necessarily a disorder. Some fairly normal phenomena are perhaps psychosomatic.

55. Are psychosomatic effects paradoxical? They certainly do not appear to take off from a specific intention that they not exist. I suggest that although psychosomatic effects are not in themselves paradoxical, they may result from maladaptive processes that are.

56. One example has already been discussed. Panic attack symptoms, like breathing difficulties, may be due to lay intervention. Are they psychosomatic? They do seem to satisfy the definition above. For example, panic-related breathing difficulty is evidently an organic problem with physiological consequences. The severe consequences are known to be brought about by a mental factor, which is the panic. Finally, there is a real basis. This sounds strange: it is often reported that the panic comes out of the blue, which must mean that a person having no disorder would show no organic symptoms at all. The answer may be that the real basis is the level of oxygen, but it is its interpretation that makes the difference. The level is high enough to allow the normal course of respiration to proceed, but this is not known to the lay attentional process that intervenes. The inappropriate response to an innocuous state may start the rolling of the snowball.

57. Why does the lay attentional process intervene in the first place? Several possible reasons have been mentioned in the preceding section, but in the case of panic disorders, there is another one. The person with a panic disorder is prone to fears, which may be either data-driven or conceptually driven, that the effect might soon appear. When such a fear is aroused, it automatically draws attention to the problematic sensory surface. Attempts to avoid the thoughts that act as the prime mover of the process are liable to result in the fate common to cognitive evasions, namely, activation of what is to be avoided. The basis for the fears is probably some earlier experiences. However, certain personality traits or situations might predispose the person to such fears, even with no apparent autobiographical background. It has been suggested (e.g, Barsky & Klerman, 1983; Hitchcock & Mathews, 1992; Warwick & Salkovskis, 1990) that hypochondriacs and panic patients tend to misinterpret innocuous bodily sensations as pathological. Under severe stress, this may perhaps happen with people who normally have neither hypochondriacal concern nor a tendency toward panic.

58. A similar process may be responsible for psychosomatic pains. Coping with severe pains is popularly believed to be affected by how, or how much, the pain is processed attentionally (e.g., Leventhal & Everhart, 1979; McCaul & Malott, 1984). What about faint stimulations? Whether or not some stimulation is experienced as pain probably depends on how the pain threshold is set, presumably in some modules specialized in alerting the mind whenever the risk of serious damage to the body part at which the stimulation emanates is particularly high. An intervention that leads to a voluntary redirection of attention to that sensory surface, like a remark about the pungency of a chicken curry being presently eaten, releases information about subthreshold levels of stimulation. One may regard this simply as threshold lowering. A more interesting possibility is that the information is accessed by a lay system, in that it has no idea which level of stimulation warrants alerting. Since a pain message automatically draws attention to the pain source and acts to maintain it there, there does not seem to be an easy way out of this state. Worse yet, the lay system may not know how to respond to the pain message. The pain modules are probably capable of triggering some pain inhibition after the message has been transmitted. Melzack (1973) suggested that afferent neurons can be inhibited by the cortex to reduce transmission of pain messages. It was later found (e.g., Lewis, Cannon & Liebskind, 1980; Terman, Shavit, Lewis, Cannon & Liebskind, 1984) that electric shocks enhance analgesia and that intermittent shocks increase the level of opioids in the brain. The lay systems may lack this ability to induce partial analgesia.

59. The speculations required to account for psychosomatic effects that have more severe or more observable organic consequences, such as peptic ulcers, are perhaps too wild to be worth spelling out here. However, the basic mechanism might be similar: an intervention that redirects attention to a sensory surface that is regularly accessed only by the pertinent modules brings about a cognition, which in turn leads to inappropriate responses, so that the system may be drawn into a vicious circle, or worse yet, swept into a snowball effect.


60. I have discussed here a number of examples of paradoxical effects in cognition. Fortunately for us as people, they are not very prevalent. Unfortunately for us as scientists, some of them are hard to observe, let alone to experiment with.

61. What is common to all the effects discussed here? It seems that they share some deviation from the normal assignment of processing goals to processing systems. Evasions are attempts to fool attention. Lay interventions are attempts to bypass autonomous modules or other automatic procedures. Both sorts of attempt are voluntary. The root of the evil seems to be an excessive degree of self-awareness. Information is not always an asset, especially in a system that regularly performs well on its own.

62. Perhaps the ideal division of labor in the mind is analogous to what Plato prescribed for his utopian state: Let the craftsmen work, the guards guard, and the philosophers rule. However, this is probably another utopia.


I am very much indebted to the helpful assistance and useful suggestions of Ronen Kasten. I am also indebted to comments made by PSYCOLOQUY's editor and referees.

#1. A referee of this manuscript brought to my attention a theoretical paper by Wegner (1994) that addresses several of the phenomena discussed here, primarily in the first section. I have used its excellent literature review to complement mine. Paragraph 16 discusses differences between Wegner's explanations and my own.

#2. One might contend that the arousal is due to the perception of the person. However, for what pre-experimental speculation is worth, I suspect that if the encounter were not feasible (such as when the person is viewed from a balcony), the arousal would be negligible.

#3. People with mental disorders such as obsessive-compulsive behavior show much greater lack of control over thoughts or actions than people with no diagnosed mental disorder. It is not unreasonable to conjecture that a considerable proportion of such uncontrolled thought and action may be due to evasions. In this respect, normal and abnormal behavior lie on the same continuum (cf. Rachman & de Silva, 1978; Wegner, 1994, in press).

#4. Another possibility is that the automatic processes activate the relevant nodes as they should, yet the controlled process in charge of inhibiting nodes related to those that were previously activated by the automatic processes errs by generalizing the inhibition to the to-be-recalled item (Schvaneveldt, Durso & Mukherji, 1982). I doubt that this can be the main explanation of failures to recall proper names and rare words, however, because in such cases one is often conscious of some features of the target but not of the target itself (Brown & McNeill, 1966). It is hard to believe that the latter is retrieved and then inhibited, whereas the former are not inhibited.


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