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B Milliken

Publications and source records attributed to B Milliken.

12 recordsLinked to original sources
PubMed2001

On the strategic modulation of the time course of facilitation and inhibition of return.

In studies of exogenous attentional orienting, response times for targets at previously cued locations are often longer than those for targets at previously uncued locations. This effect is known widely as inhibition of return (IOR). There has been debate as to whether IOR can be observed in discrimination as well as detection tasks. The experiments reported here confirm that IOR can be observed when target discrimination is required and that the cue-target interval at which IOR is observed is often longer in discrimination than in detection tasks. The results also demonstrate that the later emergence of IOR is related to perceptual discrimination rather than to response selection differences between discrimination and detection tasks. More difficult discrimination tasks lengthen the SOA at which IOR emerges. In contrast, increasing task difficulty by adding a distractor to the location opposite the target shortens the SOA at which IOR emerges. Together, the results reveal an adaptive interaction between exogenous and endogenous attentional systems, in which the action of the orienting (exogenous) system is modulated endogenously in accord with task demands.

Attention↗
PubMed2000

Attending, ignoring, and repetition: on the relation between negative priming and inhibition of return.

A series of spatial localization experiments is reported that addresses the relation between negative priming and inhibition of return. The results of Experiment 1 demonstrate that slowed responses to repeated location stimuli can be obscured by repetition priming effects involving stimulus dimensions other than spatial location. The results of Experiments 2, 3A, and 3B demonstrate that these repetition priming effects may occur only when participants are required to respond to the prime display. Together, these results suggest that differences between attended and ignored repetition effects in selective attention studies of spatial localization do not provide a basis for distinguishing between spatial negative priming and inhibition of return.

Adult↗
PubMed1999

Inhibition of return and the attentional set for integrating versus differentiating information.

Cuing a location with an uninformative cue leads to a facilitatory effect at that location shortly afterward and later (about 300 ms) to a negative effect called inhibition of return (IOR). Until recently, it was argued that IOR occurs in detection and localization tasks, but not in discrimination tasks. However, the authors of several recent studies have demonstrated IOR effects in discrimination tasks, although at a later cue-to-target stimulus onset asynchrony (SOA). In this study, the authors examined why IOR occurs at a later SOA in discrimination tasks. In Experiments 1 and 2, different time courses of exogenous cuing effects in detection and discrimination tasks were established. In Experiment 3, the authors examined the role of an attentional set on the time course of exogenous cuing effects by manipulating the proportion of trials in which a distractor is presented in the location opposite the target. A new framework for understanding exogenous cuing effects and their dependence on endogenous attention is proposed.

Adult↗
PubMed1998

Diazepam-treated female rats: flumazenil- and PK 11195-induced withdrawal in the hippocampus CA1.

Six female rats had a loading dose of 180 mg of diazepam (DZ) contained in two Silastic capsules implanted in their backs. Thereafter, a single 90-mg capsule was implanted weekly for 4 weeks prior to weekly microinjections of 1 microl of flumazenil (6.25, 12.5, or 25 microg) and PK 11195 (3.125, 6.25, or 12.5 microg) or vehicle into the CA1. Three control rats had empty capsules implanted but received only the high dose of flumazenil after 5 weeks. The time of DZ exposure spanned 8 weeks. Mean steady-state plasma levels of DZ were 1.06 +/- 0.11, and the mean total (DZ + metabolites) was 2.46 microg/ml +/- 0.37. Flumazenil elicited a dose-related precipitated withdrawal score (PAS) in DZ-treated rats (but not in controls) characterized by dose-related increases in convulsive (twitches and jerks), motor and autonomic signs, dose-related increases in the percent of total power in the low frequency (1-4 Hz), and decreases in the high-frequency (18-26 Hz) bands of the EEG recorded from the dentate and the amygdala. PK 11195 produced a dose-related increase in the 4-12 Hz band of the EEG recorded from the CA1, whereas the PAS was mild and not dose-related. However, the 6.25 and 12.5-microg doses elicited a significant PAS that tended to increase with dose. These data indicate that chronic DZ produces dependence, and that in the CA1 it involves the participation of central and possibly peripheral benzodiazepine (BZ) receptors located within this structure.

Animals↗
PubMed1998

Selective attention: a reevaluation of the implications of negative priming.

The notion that inhibitory processes play a critical role in selective attention has gained wide support. Much of this support derives from studies of negative priming. The authors note that the attribution of negative priming to an inhibitory mechanism of attention draws its support from a common assumption underlying priming procedures, together with the procedure that has been used to measure negative priming. The results from a series of experiments demonstrate that selection between 2 competing prime items is not required to observe negative priming. This result is demonstrated across several experiments in which participants named 1 of 2 items in a second display following presentation of a single-item prime. The implications of these results for existing theories of negative priming are discussed, and a theoretical framework for interpreting negative priming and several related phenomena is forwarded.

Adult↗
PubMed1998

Inhibitory processes in auditory selective attention: evidence of location-based and frequency-based inhibition of return.

The possibility that there is an inhibitory component to auditory covert orienting was addressed. Each trial consisted of a cue followed by a target, and listeners were required to detect, localize, or identify the frequency of the target. At 150-msec stimulus onset asynchrony (SOA), performance was best when stimuli sounded from the same location or were of the same frequency. However, at 750-msec SOA, performance was best when stimuli differed in location or were of different frequencies. These results document the existence of both location-based and frequency-based auditory inhibition of return.

Attention↗
PubMed1997

Negative Priming, Attention, and Discriminating the Present from the Past

Priming effects have been used widely as a tool to study attentional processes. However, inferences regarding attention depend on how priming effects are interpreted. In the case of negative priming, an activation-based framework for interpreting priming suggests that attention inhibits the representation of prime distractors and that this inhibition is measured in performance to subsequent probes. Data summarized in this article point out that negative priming does not depend on selection of one of two primes and that attentional influences during retrieval play an important role in determining negative priming. Also, two experiments are described that demonstrate a correlation between priming effects and knowledge of the relation between primes and probes. We suggest that negative priming is not determined directly by a process of ignoring, but instead occurs because a repeated probe is less temporally distinct when ignored as a prime than when attended.

Journal Article↗
PubMed1996

Negative priming without overt prime selection.

The procedure typically used to demonstrate negative priming requires subjects to respond to one of two simultaneously presented stimuli across two consecutive displays. Negative priming is defined by slower responses to targets in the second display that appeared as distractors in the first display, than to targets in the second display that did not appear in the first display. It is widely assumed that negative priming occurs as a result of the selection that occurs in the first display. In the present article, we show that negative priming can be observed without requiring subjects to respond selectively to one of two items in the first display. We argue that this result is useful for two reasons. First, it points out a fundamental misunderstanding concerning the procedure required to measure negative priming, a misunderstanding that has shaped much of the theoretical work done in this area. Second, we suggest that the procedure introduced here is of considerable utility in evaluating theoretical accounts of negative priming. To demonstrate this utility we report the results of two studies that assess the code co-ordination account of negative priming.

Adult↗
PubMed1992

Size effects in visual recognition memory are determined by perceived size.

Recognition memory for shapes has been shown to depend on differences between the size of shapes at the time of encoding and at the time of the memory test (Jolicoeur, 1987). Experiment 1 of the present paper replicates this effect and establishes a set of parameters used in the subsequent experiments. Experiment 2 considers the results of Experiment 1 in light of the distinction between "perceived" size, which, under normal viewing conditions, varies minimally with changes in distance between the observer and object, and "retinal" size, which varies proportionally with viewing distance as an object is moved closer to or farther from an observer. Subjects studied novel shapes and performed a recognition memory test in which the distance from the subject to the viewing screen at the time of testing was different from that at the time of encoding. The viewing distance and the size of the shapes were manipulated such that perceived and retinal sizes were dissociated. The results suggest that the size-congruency effect in memory for visual shape occurs as a result of changes in the perceived size of shapes between the encoding and the testing phases, with little or no contribution of retinal size per se.

Distance Perception↗
PubMed1989

Identification of disoriented objects: effects of context of prior presentation.

Half of the subjects in the training phase of Experiment 1 named objects shown in a number of orientations, whereas the other half named objects shown upright only. All subjects named objects seen in a number of different orientations in the transfer phase. Half of the objects in the transfer phase were the ones they had seen in the training phase (old objects), whereas the other half were objects they had not seen before (new objects). Mean naming time in the transfer phase increased more as the objects were rotated further from the upright for new objects than for old objects when the old objects had been seen in a variety of orientations. In contrast, a substantial and equivalent orientation effect on identification time was obtained for old and new objects when the old objects had been seen upright only. These results suggest that the extraction and use of orientation-invariant attributes to identify objects is not a "default" identification strategy employed by the human visual system. In Experiment 2, half of the objects named in the training phase were shown upright only, whereas the other half were shown in a number of orientations. Both types of objects (upright vs. rotated) were presented in a mixed fashion from trial to trial. The results revealed that prior naming of the objects in this context resulted in equivalent reductions in the magnitude of the orientation effect on identification time for both sets of objects (upright and rotated). Together, the results of these two experiments suggest that markedly different representations of objects are encoded, depending on the context in which objects are seen. Implications for models of pattern recognition are discussed.

Adult↗
PubMedDate not supplied

Negative priming, attention, and discriminating the present from the past.

Priming effects have been used widely as a tool to study attentional processes. However, inferences regarding attention depend on how priming effects are interpreted. In the case of negative priming, an activation-based framework for interpreting priming suggests that attention inhibits the representation of prime distractors and that this inhibition is measured in performance to subsequent probes. Data summarized in this article point out that negative priming does not depend on selection of one of two primes and that attentional influences during retrieval play an important role in determining negative priming. Also, two experiments are described that demonstrate a correlation between priming effects and knowledge of the relation between primes and probes. We suggest that negative priming is not determined directly by a process of ignoring, but instead occurs because a repeated probe is less temporally distinct when ignored as a prime than when attended.

Adult↗