Treatment Choice and Placebo Expectation Effects

Placebo expectations can have a strong influence on physical and mental health outcomes. In prior research examining placebo expectation effects, participants have been assigned placebo treatments rather than being actively involved in selecting their treatment. In modern health care, however, individuals are often involved in health care decisions. We review relevant literature regarding choice and placebo expectation effects and conclude that exercising choice over a treatment should strengthen placebo effects. Data relevant to this hypothesis is reviewed. Next, we provide a framework for understanding the key variables involved in mediating and moderating the influence of treatment choice on placebo expectation effects. Finally, theoretical and practical issues revolving around treatment choice in the context of placebo effects are raised.     

Dividing attention between color and shape revisited: redundant targets coactivate only when parts of the same perceptual object

When a single perceptual object provides two different reasons for a particular decision (by containing two qualitatively different targets), detailed analyses of the response-time distributions have shown that the two different reasons are jointly responsible for the final decision. The question is whether this coactivation occurs because the two targets contained by the object were from separate dimensions (e.g., color and shape) or were parts of the same perceptual object. Early work argued in favor of dimensions, implying that the types of information being processed is critical, as opposed to their sources; more recent work has argued in favor of objects. Experiment 1 in the present paper corrected for a potential bias in the design of some recent studies and found additional evidence in favor of objects. Two additional experiments directly manipulated whether redundant targets would be perceived as parts of one or two perceptual objects (while holding all else constant) and produced the strongest evidence to date that coactivation requires that the redundant targets be parts of one object. This reverses the original conclusion and suggests that the sources of information are critical, as opposed to the types. Two specific versions of the object-based model are discussed.     

Age deficits in the control of prepotent responses: evidence for an inhibitory decline

Older adults have more difficulty than younger adults appropriately directing their behavior when the required response is in competition with a prepotent response. The authors varied the difficulty of inhibiting a prepotent eye movement response by varying the response cue (peripheral onset or central arrow). The response cue manipulation did not affect prosaccade accuracy and latency for either age group and did not affect younger adults' antisaccades. Older adults' antisaccades were slower in the peripheral cue condition than in the central arrow condition. These findings are taken as support for the inhibitory deficit hypothesis of aging (L. Hasher, R. T. Zacks, & C. P. May, 1999).     

Genetic and environmental influences on pubertal development: longitudinal data from Finnish twins at ages 11 and 14

To study sources of individual differences in pubertal development, the authors fit a sex-limitation common factor model to data reported, at ages 11 and 14 years, by 1,891 twin pairs on items that comprise the Pubertal Development Scale (PDS; A. C. Petersen, L. Crockett, M. Richards, & A. Boxer, 1988). The model divides variation into a general pubertal factor and item-specific variation and, in addition, decomposes it into constituent sources. In both boys and girls, genetic influences made the largest contribution to variance common to PDS items. Genetic and nonshared environmental factors accounted for variation specific to PDS items in boys, whereas for girls, common environmental influences were added for growth spurt and menarcheal status. For both common and item-specific variation, genetic effects were partially sex specific. Subsidiary analyses found accelerated maturation in both boys and girls who at age 14 were reared in father-absent homes.     

Incidental visual memory for targets and distractors in visual search

We explored incidental retention of visual details of encountered objects during search. Participants searched for conjunction targets in 32 arrays of 12 pictures of real-world objects and then performed a token discrimination task that examined their memory for visual details of the targets and distractors from the search task. The results indicate that even though participants had not been instructed to memorize the objects, the visual details of search targets and distractor objects related to the targets were retained after the search. Distractor objects unrelated to the search target were remembered more poorly. Eye-movement measures indicated that the objects that were remembered were looked at more frequently during search than those that were not remembered. These results provide support that detailed visual information is included incidentally in the visual representation of an object after the object is no longer in view.     

The perception of emotion from body movement in point-light displays of interpersonal dialogue

We examined whether it is possible to identify the emotional content of behaviour from point-light displays where pairs of actors are engaged in interpersonal communication. These actors displayed a series of emotions, which included sadness, anger, joy, disgust, fear, and romantic love. In experiment 1, subjects viewed brief clips of these point-light displays presented the right way up and upside down. In experiment 2, the importance of the interaction between the two figures in the recognition of emotion was examined. Subjects were shown upright versions of (i) the original pairs (dyads), (ii) a single actor (monad), and (iii) a dyad comprising a single actor and his/her mirror image (reflected dyad). In each experiment, the subjects rated the emotional content of the displays by moving a slider along a horizontal scale. All of the emotions received a rating for every clip. In experiment 1, when the displays were upright, the correct emotions were identified in each case except disgust; but, when the displays were inverted, performance was significantly diminished for some emotions. In experiment 2, the recognition of love and joy was impaired by the absence of the acting partner, and the recognition of sadness, joy, and fear was impaired in the non-veridical (mirror image) displays. These findings both support and extend previous research by showing that biological motion is sufficient for the perception of emotion, although inversion affects performance. Moreover, emotion perception from biological motion can be affected by the veridical or non-veridical social context within the displays.     

Mental health professionals' attitudes towards people who are deaf

Mental health professionals' attitudes towards deaf people were examined in relation to their previous contact with deaf people and their knowledge of deafness. Data were gathered regarding different aspects of contact, including the number and type of relationships participants had had with deaf people. A cognitive-processing theory of attitude change following contact (Rothbart & John, 1985) was explored. Knowledge of deafness did not correlate with attitudes towards deaf people but a relationship was found between the amount of contact that professionals had with deaf people of equal or higher status and more positive attitudes.     

Calibrating the sociometer: the relational contingencies of self-esteem

A longitudinal daily diary study examined how chronic perceptions of a partner's regard for oneself might affect the day-to-day relational contingencies of self-esteem. Married partners each completed a diary for 21 days, and completed measures of satisfaction twice over the year. Multilevel analyses revealed that people who chronically felt more positively regarded compensated for one day's acute self-doubts by perceiving greater acceptance and love from their partner on subsequent days. In contrast, people who chronically felt less positively regarded by their partner internalized acute experiences of rejection, feeling worse about themselves on days after they feared their partner's disaffection. Over the year, such self-esteem sensitivity to rejection predicted declines in the partner's satisfaction.     

Auditory neuropathy/dys-synchrony: diagnosis and management

Auditory brainstem responses (ABRs) and otoacoustic emissions (OAEs) are objective measures of auditory function, but are not hearing tests. Normal OAEs reflect normal cochlear outer hair cell function, and an ABR indicates a synchronous neural response. It is quite possible for a patient to have normal OAEs but absent or grossly abnormal ABR and a behavioral audiogram that is inconsistent with either test. These patients, who may constitute as much as 10% of the diagnosed deaf population, have auditory neuropathy/dys-synchrony (AN/AD). To diagnose AN/AD accurately, ABRs are obtained in response to condensation and rarefaction clicks to distinguish cochlear microphonics (CM) from neural responses. Appropriate management is confounded by variation among patients and changes in auditory function in some patients over time. Recommendations for management include visual language exposure through methods such as American Sign Language (ASL), Cued Speech, or baby signs, and closely following patients.