Why do older adults have difficulty following conversations?

Age-related declines in understanding conversation may be largely a consequence of perceptual rather than cognitive declines. B. A. Schneider, M. Daneman, D. R. Murphy, and S. Kwong-See (2000) showed that age-related declines in comprehending single-talker discourse could be eliminated when adjustments were made to compensate for the poorer hearing of older adults. The authors used B. A. Schneider et al.'s methodology to investigate age-related differences in comprehending 2-person conversations. Compensating for hearing difficulties did not eliminate age-related differences when the 2 talkers were spatially separated by 9 degrees or 45 degrees azimuth, but it did when the talkers' contributions came from one central location. These findings suggest that dialogue poses more of a problem for older than for younger adults, not because of the additional cognitive requirements of having to follow 2 talkers rather than 1, but because older adults are not as good as younger adults at making use of the auditory cues that are available for helping listeners perceptually segregate the contributions of 2 spatially separated talkers.     

The two faces of typicality in category-based induction

Studies of category-based induction using different methods have found somewhat contradictory results for whether typical items are a stronger basis for induction. Typical category items are generally more similar to other category items than are atypical ones, and they are also more likely to be categorized into the category in question. We propose that the first aspect (representativeness) influences induction, but the second (uncertainty about the correct category) does not. Two experiments using artificial categories found support for this prediction. Two further experiments manipulated pictures of objects and also found that representativeness in the category influenced the strength of induction, but uncertainty of classification did not. Thus, the two aspects of typicality have different effects on category-based induction.     

Posttraumatic stress disorder symptomatology among partners of men in treatment for relationship abuse

This longitudinal study examined posttraumatic stress disorder (PTSD) symptoms among current and former female partners (N = 96) of men participating in a group treatment program for partner abuse perpetrators. Female partner probable PTSD rates, obtained during time points corresponding with pretreatment, posttreatment, and 6-month follow-up for the male clients, were 52%, 34%, and 29%, respectively. Psychological abuse exposure was more strongly and uniquely associated with PTSD symptoms than was physical abuse exposure. Among psychological abuse ratings, denigration, restrictive engulfment, and dominance/intimidation behaviors evidenced the strongest associations with PTSD symptoms. Findings from this study suggest the association between psychological abuse and PTSD is complex and multidetermined.     

The effects of establishing operations on preferences for tangible items

Researchers have demonstrated that both deprivation and satiation can affect the outcome of preference assessments for food. In the current study, paired-stimulus preference assessments for tangible items were conducted under three conditions: control, deprivation, and satiation. Three persons with developmental disabilities and 3 typically developing preschool children served as participants. The results demonstrated that deprivation and satiation influenced the outcome of preference assessments of leisure items or toys.     

Evidence for an activation locus of the word-frequency effect in lexical decision

The authors report a lexical decision experiment designed to determine whether activation is the locus of the word-frequency effect. K. R. Paap and L. S. Johansen (1994) reported that word frequency did not affect lexical decisions when exposure durations were brief; they accounted for this by proposing that data-limited conditions prevented late-occurring verification processes. Subsequently, P. A. Allen, A. F. Smith, M. Lien, T. A. Weber, and D. J. Madden (1997) and K. R. Paap, L. S. Johansen, E. Chun, and P. Vonnahme (2000) reported additional evidence that word-frequency effects do and do not have an activation locus, respectively. The authors further tested this issue in a lexical decision experiment using data-limited procedures--predicted by verification models to eliminate word-frequency effects. The authors observed word-frequency effects using individually determined exposure durations that were only 1 screen cycle longer than the exposure duration that yielded chance performance. Word-frequency effects persisted even when an adjusted measure of performance was used.     

Frequency of relation type as a determinant of conceptual combination: a reanalysis

C. L. Gagne and E. J. Shoben (1997) proposed that concepts are combined via external relations and that lexical entries include information about which relations are frequent for every modifying noun. As evidence for this view, they showed that relations associated with the modifier affected the interpretation of combinations in several studies in which subjects had to decide whether the combinations were sensible. The authors evaluated the methods and stimuli used in Gagne and Shoben's experiments and present findings suggesting that the effect of relation frequency is likely due to differences between the familiarity and plausibility of different combinations. Although relation frequency could be involved in conceptual combination, the authors concluded that better evidence is needed for this variable, controlling for other more general differences between the combinations.     

Top-down gain control in the auditory system: evidence from identification and discrimination experiments

The influence of intensity range in auditory identification and intensity discrimination experiments is well documented and is usually attributed to nonsensory factors. Recent studies, however, have suggested that the stimulus range effect might be sensory in origin. To test this notion, in one set of experiments, we had listeners identify the individual tones in a set. One baseline condition consisted of identifying four 1-kHz, low-intensity tones; the other consisted of identifying four 1-kHz, high-intensity tones. In the experimental conditions, these baseline tone sets were augmented by adding a fifth tone at either 1 or 5 kHz. Added 5-kHz tones had little effect on identification accuracy for the four baseline tones. When an added 1-kHz tone differed substantially in intensity from the four baseline tones, it adversely affected performance, with the addition of a high-intensity tone to a set of low-intensity tones having a more deleterious effect than the addition of a low-intensity tone to a set of high-intensity tones. These and further results, obtained in an exploration of this asymmetrical range effect in a third identification experiment and in two intensity-discrimination experiments, were consistent with the notion of a nonlinear amplifier under top-down control whose functions include protection against sensory overload from loud sounds. The identification data were well described by a signal-detection model using equal-variance Laplace distributions instead of the usual Gaussian distributions.     

National Stuttering Association members' opinions about stuttering treatment

As stuttering support groups, such as the National Stuttering Association (NSA), have gained prominence and visibility, it has become increasingly important for speech-language pathologists (SLPs) to learn about the people who participate in such groups. This article presents results of a brief survey completed by 200 members of the NSA to examine the opinions of support group members regarding the field of speech-language pathology and stuttering treatment options. Results indicate that NSA members hold a variety of opinions, both positive and negative, about the resources available to them. Findings highlight a number of ways in which SLPs can work with stuttering support groups, both to learn more about the needs of people who stutter and also to provide needed information about treatment options that are available for people who stutter. EDUCATIONAL OBJECTIVES: The reader will learn about and be able to describe (1) the role of support groups in stuttering treatment; (2) the people who are members of the NSA; and (3) their opinions about various issues related to stuttering and its treatment.     

How shared are age-related influences on cognitive and noncognitive variables?

Several theories have suggested that age-related declines in cognitive processing are due to a pervasive unitary mechanism, such as a decline in processing speed. Structural equation model tests have shown some support for such common factor explanations. These results, however, may not be as conclusive as previously claimed. A further analysis of 4 cross-sectional data sets described in Salthouse, Hambrick, and McGuthry (1998) and Salthouse and Czaja (2000) found that although the best fitting model included a common factor in 3 of the data sets, additional direct age paths were significant, indicating the presence of specific age effects. For the remaining data set, a factor-specific model fit at least as well as the best fitting common factor model. Three simulated data sets with known structure were then tested with a sequence of structural equation models. Common factor models could not always be falsified--even when they were false. In contrast, factor-specific models were more easily falsified when the true model included a unitary common factor. These results suggest that it is premature to conclude that all age-related cognitive declines are due to a single mechanism. Common factor models may be particularly difficult to falsify with current analytic procedures.