Undergraduates (n=490) were divided into 3 groups; each group viewed a photo of a woman either 29, 47, or 63 years old. The oldest woman received the most positive evaluation on 8 of 17 characteristics. The subjects' estimation of the women's ages was consistent with the actual ages of the women. (SK)

Assessed the relative contribution of dynamic and summary features of vocal frequency to the discrimination of pragmatic categories in infant-directed speech. Forty-nine mothers were instructed to use their voice to get their infant's attention, show approval, and provide comfort. Findings suggest that both dynamic and summary features are…

General normal ogive and logistic multiple-group models for paired comparisons data are described. In these models, scale value and discriminal dispersion parameters are allowed to vary across stimuli and respondent populations. Model fitting and hypothesis testing are illustrated using health care coverage data from two age groups. (SLD)

Using object pairs that varied orthogonally in alignability and thematic relatedness, 3 experiments involving 242 college students highlight the importance of compatibility between stimuli and processing in affecting task outcomes. Certain types of stimuli are more conducive to one type of processing than another. (SLD)

This study tested the notion that an equivalence relation may include a response when differential responses are paired with stimuli presented during training. Eight normal adults learned three kinds of computer mouse movements as differential response topographies (R1, R2, and R3). Next, in matching-to-sample training, one of the response…

Sidman's (2000) theory regarding the origin of equivalence relations predicts that a reinforcing stimulus common to distinct equivalence classes must drop out of the equivalence relations. This prediction was tested in the present study by arranging class-specific reinforcers, R1 and R2, following correct responding on the prerequisite conditional…

When participants use cues to prepare for a likely stimulus or a likely response, reaction times are facilitated by valid cues but prolonged by invalid cues. In studies on combined expectancy effects, two cues give information regarding two dimensions of the forthcoming task. When the two cues consist of two separable stimuli their effects are…

This study examines lexical performance by 3 groups of linguistically diverse school-age learners: English-only speakers with primary language impairment (LI), typical English-only speakers (EO), and typical bilingual Spanish-English speakers (BI). The accuracy and response time (RT) of 100 8- to 13-year-old children in word recognition and…

The difficulty that older listeners experience understanding conversational speech may be related to their limited ability to use information present in the silent intervals (i.e., temporal gaps) between dynamic speech sounds. When temporal gaps are present between nonspeech stimuli that are spectrally invariant (e.g., noise bands or sinusoids),…

This study examined the influence of shape similarity and labels on 13-month-olds' inductive inferences. In 3 experiments, 123 infants were presented with novel target objects with or without a nonvisible property, followed by test objects that varied in shape similarity. When objects were not labeled, infants generalized the nonvisible property…

The conditions under which stimulus over-selectivity occurred were studied using a matching-to-sample procedure with non-autistic adults. A matching-to-sample discrimination learning task with a number of sample-comparison retention intervals was used. The results demonstrated that an increase in retention interval increased the degree of stimulus…

This research investigates the development of symbolic or representational play in two species of the genus "Pan", bonobos ("Pan paniscus") and chimpanzees ("Pan troglodytes"). The participants varied not only by species, but also as to whether they had become proficient in communicating with humans via a set of arbitrary visual symbols, called…

A central problem for psychology is vision's reaction to perspective. In the present studies, observers looked at perspective pictures projected by square tiles on a ground plane. They judged the tile dimensions while positioned at the correct distance, farther or nearer. In some pictures, many tiles appeared too short to be squares, many too…

Nonautomated or tabletop procedures are widely used in derived stimulus relations research. These procedures offer several advantages to the researcher, not least of which is the interactive format of the task. However, this feature is often criticized because of the possibility of experimenter cuing and imprecise experimental control over task…

In Experiment 1, 12 senior citizens from the community were trained with 18 sets of conditional discriminations. Training included 2-, 3-, and 4-choice matching-to-sample (MTS) configurations in linear series (LS), many-to-one (MTO), and one-to-many (OTM) training structures. Training structure order was counterbalanced across participants. The…