Non-spatial context-driven search

Contexts that predict characteristics of search targets can guide attention by triggering attentional control settings for the characteristics. However, this context-driven search has most commonly been found in the spatial dimension. The present study explored the context-driven search when shape contexts predict the color of targets: non-spatial context-driven search. It has been demonstrated that context-driven search requires cognitive resources, and evidence of non-spatial context-driven search is found when there is an increase in cognitive resources for the shape/color associations. Thus, the scarcity of evidence for non-spatial context-driven search is potentially because the context-driven search requires more cognitive resources for shape/color associations than for spatial/spatial associations. In the current study, we violated a previously 100% consistent shape/color association with two mismatch trials to encourage allocation of cognitive resources to the shape/color association. Three experiments showed that the shape-predicted color cues captured attention more than the non-predicted color cues, indicating that shape contexts triggered attentional control settings for a color predicted by the contexts. Furthermore, the shape contexts guided attention to the predicted color only after the two mismatch trials, suggesting that expression of the non-spatial context-driven search may require cognitive resources more than the spatial context-driven search.

     

Relating print and speech: the effects of letter names and word position on reading and spelling performance

From an early age, children can go beyond rote memorization to form links between print and speech that are based on letter names in the initial positions of words (Treiman & Rodriguez, 1999; Treiman, Sotak, & Bowman, 2001). For example, children's knowledge of the name of the letter t helps them learn that the novel word TM is pronounced as team. Four experiments were carried out to determine whether letter names at the ends of words are equally useful. Four- and five-year-olds derived little benefit from such information in reading (Experiments 1 and 3) or spelling (Experiment 2), although adults did (Experiment 4). For young children, word-final information appears to have less influence on reading and spelling performance than does word-initial information. The results help delineate the circumstances under which children can go beyond a logographic approach in learning about print.     

The formation of a generalized categorization repertoire: effect of training with multiple domains,samples, and comparisons

The present experiment explored the effects of three variables on the spontaneous categorization of stimuli in perceptually distinct and novel domains. Each of six stimulus domains was created by morphing two images that were the domain endpoints. The endpoints of the domains were male and female faces, two abstract drawings, a car and a truck, two banded-elevation satellite land images, a tree and a cat, and two false-color satellite images. The stimulus variants at each end of a domain defined two potential perceptual classes. Training was conducted in a matching-to-sample format and used stimuli from one or two domains, one or three variants per class as samples, and one or three variants per class as comparisons. The spontaneous categorization of stimuli in the untrained stimulus domains showed the emergence of a generalized categorization repertoire. The proportion of spontaneously categorized stimuli in the new domains was positively related to the number of domains and samples used in training, and was inversely related to the number of comparisons used in training. Differential reaction times demonstrated the discriminability of the stimuli in the emergent classes. This study is among the first to provide an empirical basis for a behavior-analytic model of the development of generalized categorization repertoires in natural settings.     

Dissociation of explicit and implicit timing in repetitive tapping and drawing movements

Four experiments explored the hypothesis that temporal processes may be represented and controlled explicitly or implicitly. Tasks hypothesized to require explicit timing were duration discrimination, tapping, and intermittent circle drawing. In contrast, it was hypothesized that timing control during continuous circle drawing does not rely on an explicit temporal representation; rather, temporal control is an emergent property of other control processes (i.e., timing is controlled implicitly). Temporal consistency on the tapping and intermittent drawing tasks was related, and performance on both of these tasks was correlated with temporal acuity on an auditory duration discrimination task. However, timing variability of these 3 tasks was not correlated with timing variability of continuous circle drawing. These results support the hypothesized distinction between explicit and implicit temporal representations.     

Intraadministration associations: conditional hyperalgesia elicited by morphine onset cues

There is evidence that exteroceptive cues associated with drug administration elicit conditional compensatory responding (e.g., hyperalgesia in organisms with a history of morphine administration). Recently it has become apparent that, within each administration, interoceptive early-drug onset cues (DOCs) may become associated with the later, larger drug effect (intraadministration associations). The present experiments evaluated DOC-elicited conditional hyperalgesia in rats intravenously infused with morphine. The results indicated that DOC-elicited hyperalgesia contributes to tolerance to the analgesic effect of morphine, and such DOC-elicited hyperalgesia is an associative phenomenon, rather than a sensitized response to the opiate. The findings suggest that associative analyses of tolerance should acknowledge the conditional responding elicited by DOCs, and extinction-based addiction treatments should incorporate extinction of DOC-elicited conditional responding.     

Regularities of source recognition: ROC analysis

Source memory has become the focus of a growing number of investigations in a variety of fields. An appropriate model for source memory is, therefore, of increasing importance. A simple 2-dimensional signal-detection model of source recognition is presented. The receiver operating characteristics (ROCs) obtained from 3 experiments are then used to test the model. The data demonstrate 3 regularities: convex ROCs, z-ROCs with linear slopes of 1.00, and slightly concave z-ROCs. Two of these regularities support the model. The 3rd requires a revision of the model. This revised model is fitted to the data. The implications of these regularities for other theories are also discussed.     

Action-based and vision-based selection of input: Two sources of control

In the first part of this paper we review evidence suggesting that there exists a mechanism that selects input on the basis of its similarity to the required action. This response-based input selection differs from the more established space- and object-based input selection in that it is not constrained by the structure of the input. Our evidence suggests that the two-choice Stroop effect is caused by this response-based selection mechanism. By contrast, it is known that the flanker effect is determined by the space- and object- based selection mechanisms. We explore whether the conflict resolution of the Stroop and flanker tasks is different as well by embedding these two tasks in a PRP (Psychological Refractory Period) paradigm. We show that the Stroop and the PRP effects are additive whereas the flanker and the PRP effects are underadditive, suggesting that the processes in charge of the conflict resolution in the Stroop and the flanker tasks are indeed different. We discuss possible reasons for this difference, and discuss possible ways in which the response-based mechanism can be implemented in information processing models.     

Differential functioning of the Beck depression inventory in late-life patients: use of item response theory

The present analyses examined age-related measurement bias in responses to items on the revised Beck Depression Inventory (BDI) in depressed late-life patients versus midlife patients. Item response theory (IRT) models were used to equate the scale and to differentiate true-group differences from bias in measurement in the 2 samples. Baseline BDI data (218 late life and 613 midlife) were used for the present analysis. IRT results indicated that late-life patients tended to report fewer cognitive symptoms, especially at low to average levels of depression. Conversely, they tended to report more somatic symptoms, especially at higher levels of depression. Adjusted cutoff scores in the late-life group are provided, and possible reasons for age-related differences in the performance of the BDI are discussed.     

Variability and detection of invariant structure

Two experiments investigated learning of nonadjacent dependencies by adults and 18–month–olds. Each learner was exposed to three–element strings (e.g., pel–kicey–jic) produced by one of two artificial languages. Both languages contained the same adjacent dependencies, so learners could distinguish the languages only by acquiring dependencies between the first and third elements (the nonadjacent dependencies). The size of the pool from which the middle elements were drawn was systematically varied to investigate whether increasing variability (in the form of decreasing predictability between adjacent elements) would lead to better detection of nonadjacent dependencies. Infants and adults acquired nonadjacent dependencies only when adjacent dependencies were least predictable. The results point to conditions that might lead learners to focus on nonadjacent versus adjacent dependencies and are important for suggesting how learning might be dynamically guided by statistical structure.