Combining discrepant diagnostic information from multiple sources: Are complex algorithms better than simple ones?

Optimizing methods of combining discrepant diagnostic information from multiple sources is one of the more daunting tasks facing the field of child psychopathology. Several researchers have asserted that complex information-combining schemes, those in which certain information or sources of information are weighted differently from others, are preferable. This study provides theoretical and empirical evidence that simple information-combining schemes, those in which all information from all sources is weighted equally, will as a rule work as well as complex schemes and may even work better. The implications of these findings for diagnostic instrument and algorithm design are discussed. A two-step diagnostic procedure utilizing a simple information-combining scheme is presented.     

PROTECTIVE EQUIPMENT: CONTINUOUS AND CONTINGENT APPLICATION IN THE TREATMENT OF SELF-INJURIOUS BEHAVIOR

This study evaluated the use of protective equipment in treating self-injurious behavior (SIB) exhibited by three retarded persons. In Experiment 1, the equipment was first applied continuously during 20-min sessions in individual multiple baseline designs across settings. Results showed substantial reductions in head hitting, eye gouging, and hand biting. Brief periods of time-out with the protective equipment were later made contingent on SIB and combined with a differential reinforcement procedure. Reduced levels of SIB was maintained with all subjects. Additionally, the amount of time during which the equipment was applied decreased as the SIB diminished. Experiment 2 evaluated the use of contingent protective equipment (the final condition in Experiment 1) when applied directly in the subjects' living uints during the day. During Experiment 2, SIB remained at or below the levels found at the termination of Experiment 1. Finally, in an effort to assess the long-term effectiveness of the procedure, responsibility for implementation was given to the staff who were typically assigned to provide therapy to the subjects. Follow-up probe observations conducted up to 104 days after termination of the final experimental condition showed continued low levels of both SIB and equipment usage. Results of these experiments suggest that contingent protective equipment and differential reinforcement may be effective in reducing chronic self-injury.     

Visual-field differences in picture-word interference

Picture-word interference refers to the fact that if a picture (i.e., line drawing) is presented centrally with a word superimposed, picture-naming latency is longer than if that same picture is presented alone. This phenomenon, like the Stroop phenomenon, seems to be strongly influenced by the nature of the to-be-ignored word. That is, if the word names a member of the picture's semantic category additional interference is observed; however, if the word is replaced by a phonetically unviable consonant string interference is reduced. In the present experiments these effects were examined in the situation where the picture-word stimuli were presented unilaterally in either the left or right visual field. For right-visual-field presentations, phonetic and semantic factors both influenced performance just as in central presentations. As such, these results can be satisfactorily explained in terms of response competition processes. However, the results for the left-visual-field presentations were quite different. Although substantial interference was observed for all types of stimuli, the amount of interference was essentially independent of the linguistic nature of the superimposed letter string. These results do not appear to be explainable in terms of response competition processes. Instead, it is suggested that the best way to explain these results is in terms of the perceptual capabilities of the right hemisphere.     

Discrimination of auditory target dimensions in the presence or absence of variation in a second dimension by infants

Discrimination of two acoustic dimensions of auditory stimuli, vowel identity and pitch contour, was tested with infants between the ages of 4 and 16 weeks using the high-amplitude sucking (HAS) technique. Discrimination of the vowel dimension and the pitch dimension was tested under two conditions: when a change in the target dimension occurred in theabsence of constant variation in a second dimension, and when a change in the target dimension occurred in thepresence of constant variation in a second dimension. In addition, discrimination was tested in a combined condition in which one level of the vowel dimension was always combined with one level of the pitch dimension and the stimulus change to be detected was a recombination of the levels of each dimension. Sucking-recovery scores demonstrated that infants always discriminated a change in the target dimension when it occurred without variation in the second dimension, regardless of the dimension that served as the target. However, while variation of the pitch dimension did not alter vowel discrimination, variation in the vowel dimension interfered with discrimination of the pitch dimension. Discrimination was also not evidenced in the combined condition. Analysis of the group time-to-habituation (TH) data revealed that significantly longer TH scores were correlated with a failure to demonstrate discrimination. The data are discussed in terms of the formation of auditory perceptual categories in early infancy as they relate to the acquisition of speech and language and, more generally, to developmental attention and memory for auditory stimuli.     

The Toronto Word Pool: Norms for imagery,concreteness, orthographic variables,and grammatical usage for 1,080 words

Imagery and concreteness norms and percentage noun usage were obtained on the 1,080 verbal items from the Toronto Word Pool. Imagery was defined as the rated ease with which a word aroused a mental image, and concreteness was defined in relation to level of abstraction. The degree to which a word was functionally a noun was estimated in a sentence generation task. The mean and standard deviation of the imagery and concreteness ratings for each item are reported together with letter and printed frequency counts for the words and indications of sex differences in the ratings. Additional data in the norms include a grammatical function code derived from dictionary definitions, a percent noun judgment, indexes of statistical approximation to English, and an orthographic neighbor ratio. Validity estimates for the imagery and concreteness ratings are derived from comparisons with scale values drawn from the Paivio, Yuille, and Madigan (1968) noun pool and the Toglia and Battig (1978) norms.     

Reliability of psychophysiological assessment

In order to assess the reliability of psychophysiological recording, 15 subjects were assessed on multiple response measures (forehead EMG and forearm flexor EMG, heart rate, skin resistance level, hand surface temperature and cephalic vasomotor response), under multiple stimulus conditions (baseline, self-control, cognitive and physical Stressors), on multiple occasions (Days 1, 2, 8 and 28). Three forms of reliability coefficients were computed for each response measure: coefficients on absolute scores, coefficients on change scores from baseline to stressful conditions and coefficients on percent change from baseline. Only frontal EMG appeared to have consistently high absolute reliability coefficients, with hand surface temperature having high reliability if sessions are repeated within 1 week. Heart rate was less consistently reliable. Treating the responses as relative measures did not increase their reliability; indeed, hand surface temperature was completely unreliable when examined in this fashion. Implications of this study for behavioral medicine, biofeedback and anxiety-based disorders research, as well as Lang's tripartite response system model of fear and emotion, are discussed.     

Stress management training for law students: Cognitive-behavioral intervention

The practice of law has created chronic and, at times, severe psychological stress both in law school and subsequent practice. In the current study, students volunteered to participate in a six-session seminar on personal stress management skills including self-relaxation training, schedule planning, priority-setting, leisure time planning, and cognitive modification techniques. Subjects showed pre- to posttreatment improvement on a variety of measures that included their knowledge about stress, personal ratings of stressful situations, and their daily activity schedules. In contrast, a control group showed no improvement and worsened in reported levels of personal stress. The importance of providing law students with personal stress management skills is discussed.     

Feminist and sympathetic feminist consciousness

Data from the 1976 American National Election Study were used to assess the effects of one outgroup characteristic, belief similarity—dissimilarity, on the enhancement of women's feminist consciousness. Women were focused on as the ingroup and men as the outgroup. The sample consisted of 677 women who believed that women should have an equal role with men. Outgroup belief similarity referred to women's perception that most men supported an equal role for women and outgroup dissimilarity to the perception that men did not support an equal role. Results indicated that outgroup belief similarity significantly enhanced women's feminist consciousness. Women who supported an equal role and perceived outgroup belief dissimilarity scored higher on cognitive and behavioural measures of feminist consciousness than those who supported an equal role but did not perceive outgroup dissimilarity. Secondary analyses were undertaken assessing the effect of ingroup belief similarity dissimilarity on the enhancement of sympathetic feminist consciousness among men.