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PubMed1991

Redundancy in perceptual-motor testing: confirmation and generalization.

The Developmental Test of Visual-motor Integration was administered to 63 children in regular classrooms and 51 children in Special Education. Prediction based on total score (r = .68) was similar to a multiple R utilizing only five scores (.67). The over-all raw test score, based on all 24 designs, correctly classified 85% of the children while a combined abbreviated score utilizing only 5 designs achieved an 80% differentiation. Results were interpreted as confirming the hypothesis of redundancy in this perceptual-motor test.

Attention↗
PubMed1992

Consistency of interform content for the Gordon Test of Visual Imagery Control.

A total of 116 undergraduates (49 men, 67 women) completed the Gordon Test of Visual Imagery Control followed immediately by another form. Scores were higher for women than for men and on the original than on the new version. Alternate-form reliability coefficients were .517 for the complete sample, .712 for men, and .210 for women. It was concluded that consistency across content was lower than desirable.

Attention↗
PubMed1983

Quantitative studies of stimulus coding in first-order vibrissa afferents of rats. 2. Adaptation and coding of stimulus parameters.

Mechanosensory neurons are often classified as either rapidly adapting or slowly adapting. We examined response decay (adaptation) during constant deflection of the vibrissae with quantitative, repeatable, ad hoc measures. We found that first-order vibrissa-activated neurons of the fifth ganglion exhibit a variety of adaptation rates that appear to be distributed continuously between the rapidly and slowly adapting extremes. Also, adaptation rate is influenced markedly by stimulus magnitude. We found no evidence for a dichotomy within the more slowly adapting neurons on the basis of discharge regularity. Threshold tuning curves were used to evaluate vibration sensitivity. Both the best frequencies and 1:1 discharge thresholds for sinusoidal stimulation ranged over two orders of magnitude and were continuously distributed. First-order vibrissa-activated afferents exhibit a broad variety of response patterns to constant-velocity stimulation. The pattern of discharge varied both as a function of time during constant-velocity (ramp) deflection and as a function of stimulus velocity. Although information about the parameters of a stimulus may be conveyed by any of several features of the response pattern, it appears that few if any neurons function as "pure" encoders of any particular stimulus parameter. We examined quantitatively the relationship between discharge rate and both velocity and amplitude of vibrissa deflection with the aid of a computer-based curve-fitting procedure. We found that about half the observed rate-level functions were best described by a power function; the remainder were best fit by a logarithmic function. The parameters of the best-fitting functions varied widely and continuously, emphasizing further the diversity of coding properties of the rat's vibrissa afferents. Rate-level curves for stimulus magnitude generally exhibited saturation; some were nonmonotonic. None were described adequately by either a logarithmic function or a power function.

Adaptation, Physiological↗
PubMed2006

When similarity and causality compete in category-based property generalization.

Five experiments were performed to investigate the category-based generalization of nonblank properties, properties that were novel but that were attributed to existing category features with causal explanations. Experiments 1-3 tested how such explanations interact with the well-known effects of similarity on such generalizations. The results showed that when the causal explanations were used, standard effects of typicality (Experiment 1), diversity (Experiment 2), or similarity itself (Experiment 3) were almost completely eliminated. Experiments 4 and 5 demonstrated that category-based generalizations exhibit some of the standard properties of causal reasoning; for example, an effect (i.e., a novel category property) is judged to be more prevalent when its cause (i.e., an existing category feature) is also prevalent. These findings suggest that category-based property generalization is often an instance of causal inference.

Animals↗
PubMed2006

Specialization and semantic organization: evidence for multiple semantics linked to sensory modalities.

The present article reviews the case for multiple systems in semantic memory and empirically evaluates a multiple semantics proposal based on sensory modalities. In the experiments, a conceptual switching cost paradigm was used (Pecher, Zeelenberg, & Barsalou, 2003), in which participants verified properties for concepts and verification time was compared for target trials (e.g., a dog can bark) that were preceded by context trials of either the same or a different modality (e.g., a bee can buzz or a horse can have spots). Experiment 1 involved a modality switch while controlling for the concept's category and demonstrated that when modalities were switched, a processing cost was incurred that could not be attributed to the latter dimension. Experiment 2 further supported this conclusion by showing that, in a reverse situation, the cost incurred when category was switched was at least smaller. The results are discussed by considering possible alternative amodal explanations and other data that have shown the influence of sensory information in conceptual processing.

Adolescent↗
PubMed2006

Exemplar similarity, study list homogeneity, and short-term perceptual recognition.

Kahana and Sekuler (2002) conducted short-term perceptual recognition experiments and modeled the data with a noisy exemplar similarity model. They found model-based evidence that list homogeneity (i.e., the degree to which exemplars on a study list are similar to one another) exerted a significant impact on recognition performance--a finding that is not predicted by standard global familiarity models. A potential limitation of their experiments is that they tested complex stimuli in which psychological similarities among exemplars may have been misspecified. Also, the relative importance of list homogeneity was not compared with that of alternative forms of parametric variation in the model. We conducted conceptual replications of their experiments, using a simpler set of stimuli in which interexemplar similarities could be more precisely measured. Extensive model-based comparisons reveal, in accord with the results of Kahana and Sekuler, strong evidence for a role of listhomogeneity on old-new recognition performance. We suggest that subjects systematically adjust their response criteria on the basis of the homogeneity of the study list items.

Attention↗
PubMed2006

Release from generation failure: the role of study list structure.

Three experiments, using the original encoding-specificity paradigm, investigated the role of study list structure in producing Higham and Tam's (2005) generation failure effect. Generation failure occurs when cued recall performance for strong, extralist cues is worse than target production in a control group that is given no study list but is instead required merely to generate responses to the same test cues. In the present study, generation failure was replicated in Experiment 1, and Experiment 2 demonstrated that strong, extralist cues were more likely to elicit targets in pure generation groups when participants had studied a list of strong associates than when they had studied a list of weak ones. In Experiment 3, participants were released from generation failure when a study list of moderate associates was used and the cue-to-target associative strength was equated between the reinstated- and extralist-cue conditions. Together, these results suggest that generation failure is partly attributable to participants' searching inappropriate domains that, though consistent with the study list structure, are unlikely to contain targets.

Cues↗
PubMed2006

Influence of attended repetition trials on negative priming in younger and older adults.

A lengthened response time when a distractor becomes a target, called negative priming, is an undisputed phenomenon in selective attention, yet just what the underlying mechanism responsible for negative priming is has not been resolved. In this study, the proportion of attended repetition trials was manipulated in order to test the predictions of three theories that have been proposed for explaining spatial negative priming: distractor suppression (e.g., Tipper, 1985), episodic memory retrieval (e.g., Neill, Valdes, & Terry, 1995), and novelty bias (e.g., Milliken, Tipper, Houghton, & Lupiáñez, 2000). The results supported the proposal that a novelty bias, which is flexible and can be overridden, is the primary mechanism responsible for priming in spatial tasks. Memory retrieval obscured the novelty bias for target processing, was more selective in older adults, and did not affect distractor processing. Novelty bias and distractor suppression may share the same inhibitory attentional mechanism.

Adolescent↗
PubMed2006

Calculation latency: the mu of memory and the tau of transformation.

Does numeral format (e.g., 4 + 8 vs. four + eight) affect calculation per se? University students (N = 47) solved single-digit addition problems presented as Arabic digits or English words and reported their strategies (memory retrieval or procedures such as counting or transformation). Decomposition of the response time (RT) distributions into mu (reflecting shift) and tau (reflecting skew) confirmed that retrieval trials contributed predominantly to mu whereas procedure trials contributed predominantly to tau. The format x problem size RT interaction (i.e., greater word-format RT costs for large problems than for small problems)was associated entirely with mu and not with tau. Reported use of procedures presented a corresponding format x size interaction. Together, these results indicate that, relative to the well-practiced digit format, the unfamiliar word format disrupts number-fact retrieval and promotes use of procedural strategies.

Adolescent↗
PubMed2002

Mixing location-irrelevant and location-relevant trials: influence of stimulus mode on spatial compatibility effects.

The performance advantage for spatially compatible mappings of physical locations to keypress responses, relative to incompatible mappings, is eliminated when stimulus color, rather than location, is relevant on half of the trials. In Experiment 1, we compared the effects of mixing for different stimulus modes (physical locations, arrow directions, and location words) to determine whether this elimination of the stimulus-response compatibility (SRC) effect would generalize to other stimulus modes. The SRC effect was unaffected when the location information was conveyed by arrows and was amplified when the location information was conveyed by words. In Experiment 2, we used vocal left-right responses instead of keypresses, and the SRC effects for all three stimulus modes were enhanced by mixing. In both experiments, for all stimulus modes, mixing reduced or reversed correspondence effects for trials on which the location information was irrelevant when the mapping for those trials on which it was relevant was incompatible. These findings suggest that when trial types are mixed, direct activation of the corresponding response, regardless of mapping, does not occur for physical locations mapped to keypresses. However, such activation does occur when stimuli or responses are verbal, apparently because performance is mediated in part by activation of a verbal name code for the stimulus.

Humans↗
PubMed2003

A new set of 299 pictures for psycholinguistic studies: French norms for name agreement, image agreement, conceptual familiarity, visual complexity, image variability, age of acquisition, and naming latencies.

Pictures are often used as stimuli in studies of perception, language, and memory. Since performances on different sets of pictures are generally contrasted, stimulus selection requires the use of standardized material to match pictures across different variables. Unfortunately, the number of standardized pictures available for empirical research is rather limited. The aim of the present study is to provide French normative data for a new set of 299 black-and-white drawings. Alario and Ferrand (1999) were closely followed in that the pictures were standardized on six variables name agreement, image agreement, conceptual familiarity, visual complexity, image variability, and age of acquisition. Objective frequency measures are also provided for themost common names associated with the pictures. Comparative analyses between our results and the norms obtained in other, similar studies are reported. Finally, naming latencies corresponding to the set of pictures were also collected from French native speakers, and correlational/multiple-regression analyses were performed on naming latencies. This new set of standardized pictures is available on the Internet (http://leadserv.u-bourgogne.fr/bases/pictures/) and should be of great use to researchers when they select pictorial stimuli.

Adolescent↗
PubMed2004

A new breed of computer users: rats control a cursor via joystick manipulation.

Many exciting findings have been reported in the 15 years since monkeys were first demonstrated to have the capacity to perform computerized tasks. The present data indicate that albino rats can also learn to respond to computer-generated stimuli by manipulating a joystick. Although the rat's control of the cursor is not as skillful as has been reported for primate species, it is clearly better than chance and suggests the great potential for comparative investigation afforded by use of the computer test system.

Animal Experimentation↗