Adulthood age differences in causal attributions for cognitive, physical, and social performance

Past research has revealed an unflattering pattern of attributions for the performance of the elderly. More specifically, poor performance by the elderly is attributed to internal and stable factors such as inability, whereas poor performance by the young is attributed to external and unstable factors such as bad luck. In the present study, 42 young (M age = 19.18 years) and 39 elderly (M age = 74.90 years) men and women made causal attributions for their own or for another person's hypothetical performance in the cognitive, physical, and social domains. When attributions for the same performance by young and elderly adults were compared, the results presented an unflattering view of the elderly, similar to the pattern in previous research. In contrast, when attributions for good versus poor performance by the elderly were compared, a more favorable picture emerged: The elderly were more likely to be given credit for their good performance than to be blamed for their poor performance. These findings give reason to question the pervasiveness of the negative view of the elderly that has been presented in previous studies.     

Auditory apparent motion in the free field: the effects of stimulus duration and separation.

The effects of stimulus duration and spatial separation on the illusion of apparent motion in the auditory modality were examined. Two narrow-band noise sources (40 dB, A-weighted) were presented through speakers separated in space by 2.5 degrees, 5 degrees, or 10 degrees, centered about the subject's midline. The duration of each stimulus was 5, 10, or 50 msec. On each trial, the sound pair was temporally separated by 1 of 10 interstimulus onset intervals (ISOIs): 0, 2, 4, 6, 8, 10, 15, 20, 50, or 70 msec. Five subjects were tested in nine trial block; each block represented a particular spatial-separation-duration combination. Within a trial block, each ISOI was presented 30 times each, in random order. Subjects were instructed to listen to the stimulus sequence and classify their perception of the sound into one of five categories: single sound, simultaneous sounds, continuous motion, broken motion, or successive sounds. Each subject was also required to identify the location of the first-occurring stimulus (left or right). The percentage of continuous-motion responses was significantly affected by the ISOI [F(9,36) = 5.67, p less than .001], the duration x ISOI interaction [F(18,72) = 3.54, p less than .0001], and the separation x duration x ISOI interaction [F(36,144) = 1.51, p less than .05]. The results indicate that a minimum duration is required for the perception of auditory apparent motion. Little or no motion was reported at durations of 10 msec or less. At a duration of 50 msec, motion was reported most often for ISOIs of 20-50 msec.(ABSTRACT TRUNCATED AT 250 WORDS)     

Motion coherence and conjunction search: implications for guided search theory.

Feature integration theory has recently been revised with two proposals that visual conjunction search can be parallel under some circumstances--either because items with nontarget features are inhibited, or because items with target features are excited. We examined whether excitatory or inhibitory guidance controlled conjunction search for an X oscillating in one direction among Os oscillating in that direction and Xs oscillating in another. Search was affected by whether items oscillated in phase with each other, and it was exceptionally difficult when items with target motion moved out of phase with each other and items with nontarget motion moved out of phase. The results suggest that conjunction search can be guided both by excitation of target features and by inhibition of nontarget features.     

Reception of Morse code through motional, vibrotactile, and auditory stimulation

The potential for communication through the kinesthetic aspect of the tactual sense was examined in a series of experiments employing Morse code signals. Experienced and inexperienced Morse code operators were trained to identify Morse code signals that were delivered as sequences of motional stimulation through up-down displacements (roughly 10 mm) of the fingertip. Performance on this task was compared with that obtained for both vibrotactile and acoustic presentation of Morse code using a 200-Hz tone delivered either to the fingertip through a minishaker or diotically to the two ears under headphones. For all three modalities, the ability to receive Morse code was examined as a function of presentation rate for tasks including identification of single letters, random three-letter sequences, common words, and sentences. Equivalent word-rate measures (i.e., product of percent correct scores and stimulus presentation rate) were nearly twice as high for auditory presentation as for vibrotactile stimulation, which in turn was about 1.3 times that for motional stimulation. The experienced subjects outperformed the inexperienced subjects by amounts that increased with task complexity. For example, the former were able to receive sentences at 18 words/min with motional stimulation, whereas the latter, following 75 h of training, were unable to perform this task. The present results and those of other research with tactual communication systems are compared, particularly regarding estimates of information-transfer rates.     

The three-stratum theory of cognitive abilities: Test of the structure of intelligence across the life span

Recently a three-stratum theory of intelligence that combines the major aspects of Spearman's (1927) theory of general intelligence (g) and Horn and Cattell's (1966) theory of crystallized and fluid intelligence (G_f-G_c) has been proposed (Carroll, 1993a). The purpose of this study was to test the three-stratum theory using hierarchical confirmatory factor analysis with the LISREL computer program. Developmental changes in the structure of intelligence were also investigated. Results provided support for the three-stratum theory and suggested the possibility of intermediate factors between the second and third strata but did not support developmental changes in the organization of cognitive abilities over the life span.     

Suicidal behavior among youth with severe emotional disturbance

The purpose of this study was to replicate an investigation of risk behaviors associated with suicidal behavior in public high school students, in a population of high school age youth with severe emotional disturbance (SED). Subjects for the study were clients of the South Carolina Continuum of Care (COC) (N=83). Information on suicidal thoughts and acts, aggressive behaviors, substance use and physical recklessness was gathered using a modified version of the self-report National Youth Risk Behavior Survey. Four percent of the youth reported seriously considering suicide, 8% reported planning how they would attempt suicide, 10% reported actually attempting suicide at least once, and 6% reported attempts requiring medical treatment Of the 13 youth who reported attempting suicide, four (31%) did not report planning an attempt. All suicidal behaviors except thoughts occurred more in girls than boys with SED. Alcohol and illicit drug use were associated with suicidal behavior, with larger odds ratios for attempts than for thoughts/plans. Youth with SED who use alcohol and illicit substances are particularly at risk of suicidal behavior. A high index of suspicion is appropriate when evaluating suicidal risk in girls with SED, especially in the presence of known alcohol or substance use.Continuum of Care for Emotionally Disturbed Children Division, S. C. Office of the Governor.