Structural analysis of oligosaccharide-alditols released by reductive beta-elimination from oviducal mucins of Rana dalmatina

An episodic retrieval account of negative priming (Neill, 1997; Neill & Valdes, 1992) was evaluated in three experiments. During practice, regular word pairs were presented to subjects differing numbers of times. The subjects named specific target words while they ignored specific distractor words. Following a 5-min retention interval, memory for practice was revealed: Test responses for target words exhibited positive priming that increased with increases in the number of times that the words had been attended. Test responses for distractor words exhibited either positive priming (Experiment 1) or negative priming (Experiments 2-3) that also increased with increases in the number of times that the words had been ignored. The type of priming that distractors exhibited was determined by several contextual similarities between the practice environment, in which distractors were ignored initially, and the test environments, in which they were processed subsequently. Negative priming that spanned a 5-min interval, increased with increases in the number of times that a distractor was ignored, and was sensitive to contextual changes indicated that the direction of the effect was temporally backward because the test probe cued memory for earlier processing of the priming stimulus when the distractor had been ignored.     

Negative priming without overt prime selection.

Investigated whether negative priming occurs in the absence of overt prime selection in 3 Exps using 16 college students with normal or corrected-to-normal vision as Ss. In Exp 1, Ss responded to a target item in the probe display only, instead of the usual procedure that requires Ss to also respond to 1 of the items in the prime display. In Exp 2, Ss were asked to choose the less bright of 2 probes displayed in the same color. The same procedure was used for Exp 3 except the distractor was removed from the probe display. The authors conclude that overt selection against a prime distractor in favor of a probe target is not necessary to observe negative priming. This result demonstrates a fundamental misunderstanding concerning the procedure required to measure negative priming and presents an experimental procedure that is of considerable utility in evaluating theoretical accounts of negative priming. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Perceptual grouping and visual selective attention

The present study demonstrates that incongruent distractor letters at a constant distance from a target letter produce more response competition and negative priming when they share a target's color than when they have a different color. Moreover, perceptual grouping by means of color, attenuated the effects of spatial proximity. For example, when all items were presented in the same color, near distractors produced more response competition and negative priming than far distractors (Experiment 3A). However, when near distractors were presented in a different color and far distractors were presented in the same color as the target, the response competition x distractor proximity interaction was eliminated and the proximity x negative priming interaction was reversed (Experiment 3B). A final experiment demonstrated that distractors appearing on the same object as a selected target produced comparable amounts of response competition and negative priming whether they were near or far from the target. This suggests that the inhibitory mechanisms of visual attention can be directed to perceptual groups/objects in the environment and not only to unsegmented regions of visual space.     

A common basis for recency effects in immediate and delayed recall.

Examined the effects of word frequency and list length on the long-term serial position curve in 2 experiments, using a total of 68 undergraduates. In Exp I, the object was to find a distractor activity that would be sufficient to eliminate the recency effect in conventional free recall. In Exp II, whether list length would show a similar pattern of effects in a continuous-distractor paradigm was examined. Results demonstrate that word frequency and list length had the same effects on the serial-position curve in the continuous-distractor paradigm of delayed recall that they had previously been shown to have in immediate recall. High word frequency and shorter lists led to improved recall of preterminal items but did not influence recall of terminal items. Results suggest that the same processes underlie recency effects in the 2 paradigms and that accounts that attribute recency effects to primary (or short-term) memory are inadequate. (41 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Taking a bright view of negative priming in the light of dim stimuli: Further evidence for memory confusion during episodic retrieval.

A same–different letter-matching task was used to examine the effects of stimulus intensity on negative priming, which is poorer performance when target letters have been presented as distractor letters on the immediately preceding trial. In Exp 1, with 68 college students, stimulus intensity was manipulated between-participants, whereas in Exp 2, with 32 college students, it varied randomly from trial-to-trial within-participants. In Exp 1, negative priming was equivalent for both stimulus intensities. In Exp 2, negative priming effects were larger for repeated intensity stimuli than for nonrepeated intensity stimuli, when stimulus intensity was dim. Furthermore, for repeated intensity stimuli, negative priming effects were enhanced when the overt response required to the stimulus was repeated from prime to probe trial. These results are consistent with the hypothesis that negative priming may be due to memory confusion, rather than to inhibition of the distractor stimuli. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Precuing target location in a variable set size "nonsearch" task: Dissociating search-based and interference-based explanations for set size effects.

If a target's location is validly cued before a variable set size display, then an effect of set size on detection would indicate distractor interference rather than search. Observers performed a 1-, 3-, or 5-item detection task (indicate the presence or absence of a realistic target in the context of conceptually consistent distractors) under conditions of valid or neutral spatial precuing. Results from Experiment 1, and a replication blocking cue condition (Experiment 2), indicated set size effects in the cued target-present, but not target-absent, data. Experiment 3 determined that this interference was not due to a semantic relationship between target and distractors, and Experiment 4 used a preview paradigm to argue against distractor onsets as a source of interference. Experiment 5 eliminated this interference-based set size effect by having observers preposition their eyes over the cued location in the detection scene. Findings provide evidence for a set size effect in the absence of search and suggest that distractors may systematically diminish a visual preparatory priming advantage normally benefiting target-present detection. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Phonemic storage of concrete and abstract words with auditory presentation.

Conducted 2 experiments in which Ss' recognition memory for aurally presented concrete and abstract nouns was tested. In Exp I, 56 undergraduates heard study and test lists of 20 concrete and abstract nouns. The test list contained the same 20 nouns plus 20 new nouns which rhymed or did not rhyme with the study stimuli. In Exp II, 56 new undergraduates heard the same lists as in Exp I, but also heard lists in which concrete distractors rhymed with abstract study items and vice versa. Results show that false recognition depends upon the phonemic similarity of distractors to study words, and that the effect is independent of the concreteness of the words or whether the distractor matches the study word in concreteness. While the results may be inconsistent with aspects of the dual process theory of verbal coding, they may indicate that learners use phonemic attributes for recognition when imaginal attributes are insufficient. The appearance of an overall effect of concreteness on false alarms indicates that auditory presentation can produce imagery codes. (French summary) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Priming from distractors in rapid serial visual presentation is modulated by image properties and attention.

We investigated distractor processing in a dual-target rapid serial visual presentation (RSVP) task containing familiar objects, by measuring repetition priming from a priming distractor (PD) to Target 2 (T2). Priming from a visually identical PD was contrasted with priming from a PD in a different orientation from T2. We also tested the effect of attention on distractor processing, by placing the PD either within or outside the attentional blink (AB). PDs outside the AB induced positive priming when they were in a different orientation to T2 and no priming, or negative priming, when they were perceptually identical to T2. PDs within the AB induced positive priming regardless of orientation. These findings demonstrate (1) that distractors are processed at multiple levels of representation; (2) that the view-specific representations of distractors are actively suppressed during RSVP; and (3) that this suppression fails in the absence of attention. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of cross-modal and intramodal division of attention on perceptual implicit memory.

Extant results motivate 3 hypotheses on the role of attention in perceptual implicit memory. The first proposes that only intramodal manipulations of attention reduce perceptual priming. The second attributes reduced priming to the effects of distractor selection operating in a central bottleneck process. The third proposes that manipulations of attention only affect priming via disrupted stimulus identification. In Experiment 1, a standard cross-modal manipulation did not disrupt priming in perceptual identification. However, when study words and distractors were presented synchronously, cross-modal and intramodal distraction reduced priming. Increasing response frequency in the distractor task produced effects of attention regardless of target-distractor synchrony. These effects generalized to a different category of distractors arguing against domain-specific interference. The results support the distractor-selection hypothesis. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Negative priming for spatial location?

Examined negative priming for spatial location in 2 studies. Study 1 involved combinations of target, distractor, or both, across prime and probe, being presented once to each S in a negative priming for spatial location procedure. Specifically, stimuli were presented using an oscilloscope controlled by a computer system, and the fixation display appeared immediately after a foot pedal was depressed. After 500 msec, the prime array was added to the fixation display until the S responded (depressing the key corresponding to the location of the target). In the 1st Exp, the procedure was examined across a number of Ss (12 university students; aged 20–30 yrs). In the 2nd Exp, the procedure was tested over repeated sessions with 1 S (university student; aged 23 yrs) on consecutive days. Study 2 verified the results in 13 university students. The findings suggest that negative priming in the spatial location procedure may be more closely related to inhibition of return, or to the automatic attraction of attention by new objects, than to the concepts of distractor inhibition, episodic retrieval, and feature mismatch which have traditionally been used to explain negative priming for spatial location. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Evidence for directional scanning with the order-of-report factor excluded.

Conducted 2 experiments with 40 undergraduates to study directional-scanning in tachistoscopic recogniton, using a letter-detection procedure. Displays presented in normal orientation (Exp I) were processed left to right. The left-to-right processing reflected the order of scanning rather than simply the order of report, because the S had merely to report whether a particular letter was present or absent in the display, rather than report the entire display. When left-right mirror images were presented (Exp II), the direction of scanning changed towards right to left. Further, even with mirror reversals, performance was better on word displays than on nonword displays. (French summary) (16 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Kinetics of AMPA-type glutamate receptor channels in rat caudate-putamen neurones show a wide range of desensitization but distinct recovery characteristics

In 5 experiments the authors examine the role of object-based grouping on negative priming. The experiments used a letter-matching task with multiple letters presented in temporally separated prime and probe displays. On mismatch trials, distractor letters in primes were repeated as targets in probes, or distractor and target letters were completely different. Negative priming was shown by slowed responses when distractors were repeated as targets relative to when the stimuli differed. This occurred both when only letters were presented (Experiments 1 and 4) and when letters were surrounded by boxes (Experiment 5). Experiments 2, 3, and 4 showed that negative priming was affected by the grouping of target and distractor letters in prime displays. Negative priming was reduced when 1 of the distractor letters was placed in the target box and 1 was left outside the box; facilitatory priming was observed when both distractor letters appeared in the target box. The data were accounted for in terms of there being (a) object-based competition for visual selection, (b) inhibition of distractor objects that compete for selection with target objects, and (c) activation or inhibition of the identities of all component elements within target or distractor objects.     

The role of perceptual load in negative priming.

Negative priming (NP) effects from irrelevant distractors were assessed as a function of perceptual load in the processing of prime targets. Participants searched for a target letter among a varying number of nontarget letters in the center of the display and ignored an irrelevant peripheral distractor. NP from this distractor was found to depend on the relevant search set size, decreasing as this set size was increased. The authors conclude that exhausting attention in relevant processing reduces irrelevant processing (e.g., N. Lavie, 1995), leaving less distractor processing to produce NP. This conclusion is consistent with recent reactive inhibition views for NP (e.g., G. Houghton, S. P. Tipper, B. Weaver, & D. I. Shore, 1996). (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects on search speed of the probability of target-distractor combinations.

Pigeons searched for a small target form (T) among 31 identical distractors (Ds). T and D came from the same small set, which differed by simple features. Each form appeared equally often as T or D. Search reaction time (RT) was measured. In Exp 1, RT was lower to frequent than to infrequent pairs, whether or not frequency was consistently associated with a featural difference. In Exp 2, detection of T in the location predicted by D was relatively fast. In Exp 3, search transferred to new T-D pairs. In Exp 4, probable T-D pairs and improbable T-D pairs were drawn from different sets. Again, T-D probability affected search RT. It was concluded that probability of T-D combinations, not just of targets, affects search speed; distractors may mediate this effect through within-trial priming of attention. The results are consonant with previous studies of repetition priming, cued search, transfer, and the search image. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Emotion-attention interactions in recognition memory for distractor faces.

Effective filtering of distractor information has been shown to be dependent on perceptual load. Given the salience of emotional information and the presence of emotion-attention interactions, we wanted to explore the recognition memory for emotional distractors especially as a function of focused attention and distributed attention by manipulating load and the spatial spread of attention. We performed two experiments to study emotion-attention interactions by measuring recognition memory performance for distractor neutral and emotional faces. Participants performed a color discrimination task (low-load) or letter identification task (high-load) with a letter string display in Experiment 1 and a high-load letter identification task with letters presented in a circular array in Experiment 2. The stimuli were presented against a distractor face background. The recognition memory results show that happy faces were recognized better than sad faces under conditions of less focused or distributed attention. When attention is more spatially focused, sad faces were recognized better than happy faces. The study provides evidence for emotion-attention interactions in which specific emotional information like sad or happy is associated with focused or distributed attention respectively. Distractor processing with emotional information also has implications for theories of attention. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Object-based perceptual grouping affects negative priming.

In 5 experiments the authors examine the role of object-based grouping on negative priming. The experiments used a letter-matching task with multiple letters presented in temporally separated prime and probe displays. On mismatch trials, distractor letters in primes were repeated as targets in probes, or distractor and target letters were completely different. Negative priming was shown by slowed responses when distractors were repeated as targets relative to when the stimuli differed. This occurred both when only letters were presented (Experiments 1 and 4) and when letters were surrounded by boxes (Experiment 5). Experiments 2, 3, and 4 showed that negative priming was affected by the grouping of target and distractor letters in prime displays. Negative priming was reduced when 1 of the distractor letters was placed in the target box and 1 was left outside the box; facilitatory priming was observed when both distractor letters appeared in the target box. The data were accounted for in terms of there being (a) object-based competition for visual selection, (b) inhibition of distractor objects that compete for selection with target objects, and (c) activation or inhibition of the identities of all component elements within target or distractor objects. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Constraints on the additive relationship between semantic priming and word repetition and on the interactive relationship between semantic priming and stimulus clarity.

Describes 2 experiments that manipulated priming condition, repetition, and stimulus clarity. Exp 1 with 87 undergraduates confirmed the additive relationship between semantic priming and word repetition when the time between repetitions was relatively long. Exp 2 with 82 undergraduates limited the number of intervening trials between repetitions (0, 1, 3, 7 trials). Results are interpreted as support for the position that there are 3 components to the repetition effect: sensory, lexical, and episodic. Degradation increased the repetition effect in both experiments without affecting the semantic priming effect. This was interpreted to mean that degradation had its effect late in the information processing sequence. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Strategy effects counteract distractor inhibition: Negative priming with constantly absent probe distractors.

It is an accepted, albeit puzzling finding that negative priming (NP) hinges on the presence of distractors in probe displays. In three experiments without probe distractors, the authors yielded evidence that response-biasing processes based on the contingency between prime and probe displays may have caused this finding. It is argued that it is of help in standard NP experiments to process the distractor in the prime display in order to prepare the response to the probe target. When this contingency was removed (Experiments 2 and 3), NP was reliably observed without probe distractors, whereas no NP emerged if the design contained the typical contingency (Experiment 1). For this reason, the data suggest that the absence of NP, which is usually observed under these conditions, may be due to a contingency-based component. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Effects of semantic priming on visual encoding of pictures.

We investigated the effects of semantic priming on initial encoding of briefly presented pictures of objects and scenes. Pictures in 4 experiments were presented for varying durations and were followed immediately by a mask. In Exps 1 and 2, pictures of simple objects were either preceded or not preceded by the object's category name (e.g., dog). In Exp 1 we measured immediate object identification; in Exp 2 we measured delayed old/new recognition in which targets and distractors were from the same categories. In Exp 3 naturalistic scenes were either preceded or not preceded by the scene's category name (e.g., supermarket). We measured delayed recognition in which targets and distractors were described by the same category names. In Exps 1–3, performance was better for primed than for unprimed pictures. Exp 4 was similar to Exp 2 in that we measured delayed recognition for simple objects. As in Exps 1–3, a prime that preceded the object improved subsequent memory performance for the object. However, a prime that followed the object did not affect subsequent performance. Together, these results imply that priming leads to more efficient information acquisition. We offer a picture-processing model that accounts for these results. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Dissociative prime–probe contextual similarity effects on negative priming and repetition priming: A challenge to episodic retrieval as a unified account of negative priming.

This study examined the dependence of repetition priming (RP) and negative priming (NP) as a function of prime–probe contextual similarity in a paradigm in which participants were required to respond to a letter flanked by incompatible distractor letters (e.g., ABA). Experiment 1 used prime and probe displays containing a pair of "+" symbols that were presented horizontally or vertically. Experiments 2 and 3 manipulated whether the letter triplets contained the "!" symbol. In all experiments, regardless of whether the RP trials were intermixed with the NP trials (Experiment 2) or not (Experiment 3), RP was stronger in the prime–probe similar conditions than in the prime–probe dissimilar conditions, but NP was independent of prime–probe contextual similarity. These findings suggest that NP is not necessarily stronger in conditions in which episodic retrieval of the prime is more likely. (PsycINFO Database Record (c) 2010 APA, all rights reserved)