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K Kirsner

Publications and source records attributed to K Kirsner.

At least 19 recordsLinked to original sources
PubMed2001

Predicting transfer from training performance.

The research in this paper was designed to examine the extent to which improvement on a training task can be used to predict performance on a transfer task. This aim involved evaluating the proposition that when old skills are executed in the context of new tasks, they continue to improve as if stimulus conditions have not changed. That is, power functions that describe improvement on old skills during their initial acquisition should predict further improvement on these skills during their execution in new tasks. Three experiments were performed to achieve the aim of testing this proposition. Experiment 1 revealed that old skills were executed slower in the context of a new task than was predicted on the basis of training performance. Hence improvement in the old skills appeared to be disrupted by performance of the new task. Experiment 2 was designed to examine whether this disruption was due to an increase in complexity in the task from training to transfer, or simply due to any change in task. The results suggested that any change may cause some disruption, but this disruption was greatest with an increase in task complexity. Experiment 3 was designed to examine two variables that may affect the magnitude of this effect: the relative change in task complexity from training to transfer, and the amount of practice on a task prior to a change in task. The results indicated that only the former variable had any effect. In all three experiments no effects on performance accuracy were noted, and response times in the transfer tasks eventually returned to levels predicted by training learning functions. These results were interpreted as indicating that old skills do continue to improve in new tasks as if conditions are not altered, but that disruptions caused by transfer are related to performance overheads associated with reconceptualising the task.

Adult↗
PubMed2001

The representation of "false cognates" in the bilingual lexicon.

The results of repetition priming studies with homographs such as BANK suggest that semantic constraints restrict priming to the specific meaning invoked during the study phase. Cross-language priming studies with "false cognates" (words with similar form but unrelated meanings) suggest that form similarity may be sufficient to support repetition priming, and they do not therefore support this claim. The relevant studies have used language cues (e.g., seeing the word ESTATE in the context of other Italian words) as distinct from semantic cues (e.g., INVERNO-ESTATE) to constrain meaning, however, so that interpretation is correspondingly uncertain. The experiment described in this paper was designed to answer this question: Does sequential exposure to the English word pair MANOR-ESTATE during the study phase facilitate lexical decision to the second of these words during sequential exposure to the Italian word pair INVERNO-ESTATE (i.e., winter-summer) during the test phase of the experiment? In the experiment reported below, interpretation of false cognates was constrained by meaning rather than language, and cross-language repetition priming was eliminated for false cognates. The results suggest that lexical representation in bilinguals is organized along morphological lines rather than by language.

Adult↗
PubMed2000

Knowledge partitioning: context-dependent use of expertise.

Although exceptional performance is a defining attribute of expertise, experts sometimes exhibit striking errors and performance limitations. This article reports two experiments in which experts predicted the spread of bush fires, a domain characterized by complex but well-understood physical dynamics. Although accuracy was typically high, large errors were observed when two primary predictor variables were in opposition. In a second study, the experts' behavior--in contrast to that of novices--was additionally shown to depend on problem context. In one context, experts again committed errors, whereas in another, equally domain-relevant context, the correct predictions were made. Critically, when comparing performance across contexts, completely opposing predictions were made under identical physical conditions. We therefore suggest that expertise may comprise separate, and sometimes even mutually exclusive, components of knowledge.

Cognition↗
PubMed1999

The role of sub-lexical orthography in naming: a performance and acoustic analysis.

Two experiments examined whether the duration of naming is sensitive to variables that influence pre-production processes. In Experiment 1 word naming produced longer durations than picture naming. Experiment 2 replicated this effect for low frequency items, but not for high frequency items. The results indicate that naming duration increases when conditions are likely to involve sub-lexical orthographic to phonological translation. The results are inconsistent with the proposition that input and output involve discrete or distinct information processing stages in naming where the whole response is planned in advance of response initiation. Rather, it is claimed that sub-lexical information about a printed word's pronunciation can be used to initiate a naming response before the whole response is fully prepared. The implications for models of word naming and the role of suprasegmental factors in naming are discussed.

Adult↗
PubMed1999

AANA Journal course: update for nurse anesthetists-accelerated detoxification from opioid addiction under anesthesia: the Midas touch or the emperor's new clothes?

Opioids are highly addictive substances that include natural and synthetic chemicals that mimic the effects of morphine or bind to morphine receptor sites. Traditional assisted withdrawal is a process that takes several days to weeks and is associated with a host of painful and difficult symptoms. Recently, accelerated detoxification using opioid antagonists administered while the patient is anesthetized has been promoted, with centers proliferating nationwide. Published studies of rapid detoxification under anesthesia are highly variable in quality and control, and long-term outcome data are incomplete. Well-controlled, carefully designed studies are needed to appropriately assess the efficacy, safety, and cost-effectiveness of the approach.

Anesthesia, General↗
PubMed1997

The relationship between central cues and peripheral cues in covert visual orientation.

Four experiments were conducted to compare valid and invalid cue conditions for peripheral and central cues. Experiments 1, 3, and 4 used reaction time (RT) as the dependent variable. Experiment 2 used a threshold measure. Peripheral and central cues were presented on each trial. The peripheral cue was uninformative in all experiments. The central cue was informative in Experiments 1 and 2, where it predicted stimulus side on 70% of the trials. Experiment 3 included 50% and 100% central-cue prediction conditions as well as the 70% treatment. Experiment 4 included 60%, 75%, and 90% central-cue prediction conditions. The effects of the central and peripheral cues were independent and additive in all four experiments, indicating that: (1) both cue types can act simultaneously, and that the relationship between them is additive under the conditions used in these experiments, (2) informativeness is not a necessary condition for attentional effects with peripheral cues, and (3) covert visual orientation influences sensory thresholds and RT in similar ways. The results of Experiments 3 and 4 demonstrated that the facilitation associated with peripheral cues was insensitive to manipulations which demonstrate that subjects use the informational value of the central cue to direct voluntary attention. The results are discussed with reference to two issues; first, the proposition that central and peripheral cues exert their influence on performance in independent information-processing stages, following the additive factor method, and, second, the problems raised for additive factors method when cues elicit both an "explicit" response-regarding the presence or absence of a specified letter-and an "implicit response"-involving the planning and possible execution of eye and hand movements.

Adolescent↗
PubMed1993

Dysprosody following acquired neurogenic impairment.

Dysprosody is typically associated with the dysarthrias following acquired neurogenic disturbance but it has also been associated with impairment to the cortex of the right cerebral hemisphere (Behrens, 1985). Currently there is little agreement in the clinical literature as to the locus or nature of processes involved in production and reception of prosody. This paper investigates the usefulness of two psycholinguistic models of prosody--involving "abstract" and "concrete" processes (Ladd & Cutler, 1983)--in accounting for dysprosody following motor pathway as well as cortical lesions. Four groups of 10 adult patients each participated in the study; the first group had sustained a right cerebral hemisphere cortical stroke, the second group had hypokinetic dysarthria, the third group had ataxic dysarthria, and the fourth group was normal controls. Acoustic analysis using the Kay VisiPitch/PC was conducted on pairs of matched noun phrase and noun compounds (e.g., greenhouse, green house), interrogative and declarative versions of sentences, and sentences spoken in each of four different emotional tones. Right cerebral hemisphere damaged subjects produced shorter durations than the other groups for each stimulus class. However, all of the subjects were able to use duration to signal temporal information for the lexical distinction between noun compounds and noun phrases. The results are consistent with a model of prosodic control which involves both cortical as well as physiological control processes. Current treatment for dysprosody is discussed in light of this new emphasis on cognitive control processes.

Cerebrovascular Disorders↗
PubMed1993

Context effects in repetition priming are sense effects.

This article reports three experiments that investigate the role of context in repetition priming using a lexical decision task. The experiments show that repetition priming is either eliminated or significantly reduced if a change in context also alters the perceived sense of a nonhomographic target word. If perceived sense is not altered, a change in context is inconsequential. This points to the important role played by perceived sense in repetition priming. An explanation within a sense-specific activation framework is proposed in preference to a modified processing view.

Adult↗
PubMed1987

Are there different methods of lexical access for words presented in the left and right visual fields?

Visual field differences can arise from hemispheric specializations or perceptual asymmetries. Deciding which of the two is responsible for a particular visual field difference is a recurrent problem for researchers concerned with lateral asymmetries. In the present paper, the difficulties involved in interpreting visual field asymmetries are discussed as they apply to the Young and Ellis (1985) research on the interactive effects of word length and visual hemifield on the recognition of English words. We show that one of their critical results disappears when small changes are made to their experimental procedure. Our data demonstrate that the visual field differences Young and Ellis reported were the result of preceptual asymmetries rather than different methods of lexical access in the two cerebral hemispheres.

Adolescent↗
PubMed1986

Words and hemifields: do the hemispheres enjoy equal opportunity?

A common technique in research into cerebral asymmetry in both normal and clinical populations involves the use of lateralized visual displays. The validity of this approach depends on several generally implicit assumptions about the character of the cognitive processes involved. For example, when words are used as stimuli, cognitive processing is assumed to involve either "whole-word" or "ends-in" analysis. In this way, both hemispheres are assumed to have equal opportunities to recognize the word. These assumptions are critical, because if they are wrong, explanations based on established perceptual principles may provide a sufficient and more parsimonious explanation for hemifield asymmetries than hemispheric specialization theories. This point is developed and illustrated with particular reference to word recognition and classification. From a purely perceptual viewpoint, the right visual field advantage observed in tasks using word stimuli is to be expected given the presence of systematic biases in favor of initial characters or features of words and the relationship between retinal eccentricity and visual acuity. In other words, there is no need nor justification for a hemispheric account of visual field differences in such tasks. Some of the limiting conditions and theoretical implications of this argument are identified and discussed.

Dyslexia↗
PubMed1986

Behavioral or hemispheric asymmetry: is there a default option?

The presence of acuity gradients as a moderating variable in hemifield research is not in question. Their importance as a determinant of hemifield differences is unclear, however. The major issues are as follows. First, do vertical displays provide an appropriate control for the acuity gradient? Second, do the initial letters of a word play a critical role in word recognition, either in information-theoretic terms or because the lexicon is itself organized around access codes based on the initial letter or letters of words? Third, do behavioral and hemispheric accounts provide equally attractive explanations of Task Level X Visual Field interactions? Fourth, if the two accounts are equally attractive on empirical grounds, which is to be preferred? Each of these issues is addressed in this reply to M. P. Bryden's (1986, Brain and Cognition, 5, 362-368) and J. Hellige's (1986, Brain and Cognition, 5, 369-376) comments on our article (K. Kirsner & S. Schwartz 1986, Brain and Cognition, 5, 354-361).

Brain↗
PubMed1984

Can group differences in hemispheric asymmetry be inferred from behavioral laterality indices?

A large and often contradictory literature purports to demonstrate different patterns--or at least different degrees--of hemispheric specialization across various groups of people. Schizophrenics, dyslexics, stutterers, musicians, Orientals, Jews, and many other groups have been alleged to display idiosyncratic laterality patterns. An examination of this literature reveals three important problems. First the groups concerned are rarely homogeneous. This makes it difficult to know which group characteristics, if any, are responsible for the observed differences. Second, most behavioral laterality indices are of low reliability making group differences highly unstable. Third, the validity of many behavioral laterality indices has not been substantiated. Because of these problems, it is concluded that caution should be exercised in using and interpreting laterality measures to make between-group comparisons. For now at least, group differences in laterality cannot be inferred.

Autistic Disorder↗
PubMed1983

Language processing in partial English-Japanese bilinguals: evidence from Stroop-test results.

Possible hemispheric functional differences between adolescent partial English-Japanese bilinguals and Japanese monolinguals were examined with a reversed auditory Stroop test. Subjects were requested to press their left/right hand button when they heard the target Japanese word "Otoko (male)/Onna (female)" as fast as possible. In one condition, the word and the speaker's sex weed congruent and in the other condition they were incongruent. The results of the reaction times showed that Stroop effects appeared with both responding hands in the bilingual group. On the other hand, the results of the monolinguals revealed that the Stroop effect was shown only with the left hand and not with the right hand. These results suggest that in nonproficient bilinguals, the right hemisphere may be involved in processing word meaning.

Adolescent↗