Biomedical subjects

Biljana Stevanovski

Publications and source records attributed to Biljana Stevanovski.

7 recordsLinked to original sources

PubMed2005

Feature binding and episodic retrieval in blindness for congruent stimuli: evidence from analyses of sequential congruency.

Targets are identified more poorly when presented during a congruent cued response than during an incongruent cued response (blindness effect). The authors investigated sequential trial dependencies in the blindness effect. The results show that the size of the blindness effect depends both on the previous cued response-target congruency relationship and on repetition of events from the preceding trial. This finding suggests that cued responses and targets become linked together in a single episodic trace; repeating one of these events from the preceding trial activates the other. Depending on whether the activated representation matches or conflicts with events on the current trial, target identification performance is either facilitated or impaired. Implications for action planning and feature binding are discussed.

Attention↗

PubMed2004

Interactive activation in visual word recognition: constraints imposed by the joint effects of spatial attention and semantics.

Two lexical-decision experiments investigated the effects of semantic priming and stimulus intensity when target location varied and was cued by an abrupt onset. In Experiment 1, the spatial cue was a good predictor of target location, and in Experiment 2 it was not. The results indicate that word recognition processes were postponed until spatial attention was focused on the target and that whether attention further affected word recognition depended on cue validity. The joint effects of cue validity and priming interacted when cue validity was high but were additive when cue validity was low. The joint effects of stimulus intensity and semantic priming also varied according to cue validity (i.e., interactive when high and additive when low). The results are discussed in terms of their implications for visual word recognition, the distinction between exogenous and endogenous spatial attention, and how attention is affected by visual word recognition processes.

Attention↗

PubMed2003

Congruency-induced blindness: a cost-benefit analysis.

Targets are identified more accurately when they are presented during an incongruent response (e.g., a left-pointing arrowhead presented during a right key press) than during a congruent response (e.g., a left-pointing arrowhead presented during a left key press). This effect, referred to here as congruency-induced blindness, has been hypothesised to result from the occupation of feature codes. According to the code occupation hypothesis (Behav. Brain Sci.; J. Experim. Psychol.: Human Percept. Perform.; Vis. Cogn., in press), only costs of congruency between features of a planned or executed action and a to-be-perceived target should be observed; neither costs nor benefits of incongruency are predicted by this account. In the present study, we investigated costs and benefits in identifying left and right targets directly by manipulating neutral response type and the symbols used to cue the neutral response, which produced four neutral conditions. Three important results emerged: (1). a significant main effect of RSI (suggesting that increasing temporal overlap between a planned action and target presentation interferes with perceptual reports of the target), (2). a significant main effect of congruency (showing that impairment is code-specific), and (3). clear-cut costs with little evidence for benefits. Other complex patterns of results provided additional information relevant for extant theories of perception-action interactions.

Adolescent↗

PubMed2003

Can blindness to response-compatible stimuli be observed in the absence of a response?

Blindness to response-compatible stimuli is the finding that targets are identified less accurately when presented during the planning or execution of a congruent response (e.g., right arrow presented during a right keypress) versus an incongruent response (e.g., right arrow presented during a left keypress). Accounts of this effect suggest the planning and execution of a response are critical to its observation. Five experiments investigated whether a blindness effect would be observed in the absence of a planned response. Results suggest that a planned response is not necessary to observe a content-specific blindness effect and that the blindness effect may actually comprise both an action-related component and a symbolic component that is distinct from the action-planning system.

Adult↗

PubMed2003

Lengthening the duration of response execution does not modulate blindness to action-compatible stimuli.

Action-compatible blindness refers to the finding that target stimuli are perceived less frequently if they are presented during the planning or execution of a compatible action (e.g., a left arrow presented during a left manual key press) than during an incompatible action (Müsseler & Hommel, 1997 a, b). We investigated the effect of lengthening the response execution phase in the action-compatible blindness paradigm by requiring subjects to tap a response key once or three times on the assumption that tapping three times would increase the duration of the execution phase of the response. Prior research (e.g., Stevanovski, Oriet, & Jolicoeur, 2002; Wühr & Müsseler, 2001) has shown that larger blindness effects are observed for targets presented during the execution phase of a response than after the response has been made. We investigated whether a larger blindness effect would be observed in the three-tap condition than in the one-tap condition, or whether lengthening the duration of the response would extend the time course of the blindness effect. Neither of these possibilities was supported by the data irrespective of whether the number of taps to be made was blocked or mixed within a block of trials. The results are discussed in terms of current accounts of action-compatible blindness and the possible cognitive differences between making a single response and repeating a response.

Adolescent↗

PubMed2003

Orienting in space and time: joint contributions to exogenous spatial cuing effects.

We examined whether the time course of exogenous spatial-cuing effects is sensitive to the allocation of attention in time. Expectation for a target within a particular time window following the cue was manipulated by varying the proportion of trials that appeared at each of three stimulus onset asynchronies in both a detection task and a two-alternative forced-choice discrimination task. The time course of spatial-cuing effects was sensitive to the temporal expectation manipulation only in the discrimination task. The results are discussed with reference to the role of attentional set in exogenous spatial-cuing paradigms.

Attention↗

PubMed2002

Blinded by headlights.

Target identification is impaired when targets are presented during the planning or execution of a compatible response (e.g., right-pointing arrow during a right keypress) relative to an incompatible response (Müsseler & Hommel, 1997 a, b). Examinations of this blindness to response-compatible stimuli have typically used arrowheads as targets ("<" and ">"). The importance of the target symbol was examined by manipulating subjects' interpretation of that symbol (i.e., ">" interpreted as a right-pointing arrow or as a headlight shining to the left). Targets were presented at varying times during the planning or execution of a response in order to examine the time-course of the effect. Results showed that the interpretation, and not the physical identity, of the target was important for the blindness effect. Although the blindness effect was largest during the planning and execution of a response, it was not always confined to that temporal interval.

Adult↗