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Attentional capture is an unintentional shift of visuospatial attention to the location of a distractor that is either highly salient, or relevant to the current task set. The latter situation is referred to as contingent capture, in that the effect is contingent on a match between characteristics of the stimuli and the task-defined attentional-control settings of the viewer. Contingent capture has been demonstrated for low-level features, such as color, motion, and orientation. In the present paper we show that contingent capture can also occur for conceptual information at the superordinate level (e.g., sports equipment, marine animal, dessert food). This effect occurs rapidly (i.e., within 200 ms), is a spatial form of attention, and is contingent on attentional-control settings that change on each trial, suggesting that natural images can be decoded into their conceptual meaning to drive shifts of attention within the time course of a single fixation. (Contains 5 figures and 1 footnote.)

In whole report, a sentence presented sequentially at the rate of about 10 words/s can be recalled accurately, whereas if the task is to report only two target words (e.g., red words), the second target suffers an attentional blink if it appears shortly after the first target. If these two tasks are carried out simultaneously, is there an attentional blink, and does it affect both tasks? Here, sentence report was combined with report of two target words (Experiments 1 and 2) or two inserted target digits, Arabic numerals or word digits (Experiments 3 and 4). When participants reported only the targets an attentional blink was always observed. When they reported both the sentence and targets, sentence report was quite accurate but there was an attentional blink in picking out the targets when they were part of the sentence. When targets were extra digits inserted in the sentence there was no blink when viewers also reported the sentence. These results challenge some theories of the attentional blink: Blinks result from online selection, not perception or memory. (Contains 3 footnotes, 1 table, and 5 figures.)

Is one's temporal perception of the world truly as seamless as it appears? This article presents a computationally motivated theory suggesting that visual attention samples information from temporal episodes (episodic simultaneous type/serial token model; Wyble, Bowman, & Nieuwenstein, 2009). Breaks between these episodes are punctuated by periods of suppressed attention, better known as the attentional blink (Raymond, Shapiro, & Arnell, 1992). We test predictions from this model and demonstrate that participants were able to report more letters from a sequence of 4 targets presented in a dense temporal cluster than from a sequence of 4 targets interleaved with nontargets. However, this superior report accuracy comes at a cost in impaired temporal order perception. Further experiments explore the dynamics of multiple episodes and the boundary conditions that trigger episodic breaks. Finally, we contrast the importance of attentional control, limited resources, and memory capacity constructs in the model. (Contains 17 figures, 3 footnotes and 1 table.)

A pictured object can be readily detected in a rapid serial visual presentation sequence when the target is specified by a superordinate category name such as "animal" or "vehicle". Are category features the initial basis for detection, with identification of the specific object occurring in a second stage (Evans & Treisman, 2005), or is identification of the object the basis for detection? When 2 targets in the same superordinate category are presented successively (lag 1), only the identification-first hypothesis predicts lag 1 sparing of the second target. The results of 2 experiments with novel pictures and a wide range of categories supported the identification-first hypothesis and a transient-attention model of lag 1 sparing and the attentional blink (Wyble, Bowman, & Potter, 2009). (Contains 4 footnotes and 5 figures.)

Transient attention to a visually salient cue enhances processing of a subsequent target in the same spatial location between 50 to 150 ms after cue onset (K. Nakayama & M. Mackeben, 1989). Do stimuli from a categorically defined target set, such as letters or digits, also generate transient attention? Participants reported digit targets among keyboard symbols in a changing array of 8 items. When 1 target preceded a second target in the same location at a stimulus onset asynchrony of 107 ms (but not 213 ms), the second target was reported more often than in a condition in which there was no leading target. When the 2 targets were at different locations, report of the second target was impaired. With both letters and digits as targets, the enhancement effect was shown not to be due to category priming. Critically, the attentional benefit was present whether or not participants reported the leading target. Transient attention, contingent attentional capture, popout, and Lag 1 sparing in the attentional blink may involve a common mechanism for orienting processing resources towards salient and task relevant stimuli. (Contains 2 footnotes, 5 tables and 6 figures.)

When asked to identify 2 visual targets (T1 and T2 for the 1st and 2nd targets, respectively) embedded in a sequence of distractors, observers will often fail to identify T2 when it appears within 200-500 ms of T1--an effect called the "attentional blink". Recent work shows that attention does not blink when the task is to encode a sequence of consecutive targets, suggesting that distractor interference plays a causal role in the attentional blink. Here, however, the authors show that an attentional blink occurs even in the absence of distractors, with 2 letter targets separated by a blank interval. In addition, the authors found that the impairment for identification of the 2nd of 2 targets separated by a blank interval is substantially attenuated either when the intertarget interval is filled with additional target items or when the 2nd target is precued by an additional target. These findings show that the root cause of the blink lies in the difficulty of engaging attention twice within a short period of time for 2 temporally discrete target events. (Contains 1 footnote and 5 figures.)

Viewers can easily spot a target picture in a rapid serial visual presentation (RSVP), but can they do so if more than 1 picture is presented simultaneously? Up to 4 pictures were presented on each RSVP frame, for 240 to 720 ms/frame. In a detection task, the target was verbally specified before each trial (e.g., "man with violin"); in a memory task, recognition was tested after each sequence. Target detection was much better than recognition memory, but in both tasks the more pictures on the frame, the lower the performance. When the presentation duration was set at 160 ms with a variable interframe interval such that the total times were the same as in the initial experiments, the results were similar. The results suggest that visual processing occurs in 2 stages: fast, global processing of all pictures in Stage 1 (usually sufficient for detection) and slower, serial processing in Stage 2 (usually necessary for subsequent memory). (Contains 6 footnotes and 5 figures.)

A sentence is readily understood and recalled when presented one word at a time using rapid serial visual presentation (RSVP) at 10 words/s [Potter, M. C. (1984). Rapid serial visual presentation (RSVP): A method for studying language processing. In D. Kieras & M. Just (Eds.), "New methods in reading comprehension research" (pp. 91-118). Hillsdale, NJ: Erlbaum.]. In contrast, selecting just two colored letters at 10 letters/s results in easy detection of the first target but poor recall for the second when it appears 200-500 ms later. This attentional blink disappears when all letters must be reported; instead, performance drops more gradually over serial position [Nieuwenstein, M. R., & Potter, M. C. (2006). Temporal limits of selection and memory encoding: A comparison of whole versus partial report in rapid serial visual presentation. "Psychological Science," 17, 471-475.]. Would target words in sentences escape an attentional blink? Subjects either reported two target words (in red or uppercase) or the whole 10-word sentence. There was a blink for Target 2 in partial report, but that target was easily remembered in whole report. With scrambled sentences whole report dropped but partial report was unaffected, again showing a blink. The attentional blink is not due to memory processing of Target 1, but to target selection, which is incompatible with sentence processing.

Pictures seen in a rapid sequence are remembered briefly, but most are forgotten within a few seconds (M. C. Potter. A. Staub, J. Rado. & D. H. O'Connor. 2002). The authors investigated the pictorial and conceptual components of this fleeting memory by presenting 5 pictured scenes and immediately testing recognition of verbal titles (e.g., people at a table) or recognition of the pictures themselves. Recognition declined during testing, but initial performance was higher and the decline steeper when pictures were tested. A final experiment included test decoy pictures that were conceptually similar to but visually distinct from the original pictures. Yeses to decoys were higher than yeses to other distractors. Fleeting memory for glimpsed pictures has a strong conceptual component (conceptual short-term memory), but there is additional highly volatile pictorial memory (pictorial short-term memory) that is not tapped hy a gist title or decoy picture.

A pictured object can be readily detected in a rapid serial visual presentation sequence when the target is specified by a superordinate category name such as animal or vehicle. Are category features the initial basis for detection, with identification of the specific object occurring in a second stage (Evans & Treisman, 2005), or is identification of the object the basis for detection? When 2 targets in the same superordinate category are presented successively (lag 1), only the identification-first hypothesis predicts lag 1 sparing of the second target. The results of 2 experiments with novel pictures and a wide range of categories supported the identification-first hypothesis and a transient-attention model of lag 1 sparing and the attentional blink (Wyble, Bowman, & Potter, 2009). Keywords: attentional blink, lag 1 sparing, picture processing, categorical search, transient attention DOI: 10.1037/a0018730

Transient attention to a visually salient cue enhances processing of a subsequent target in the same spatial location between 50 to 150 ms after cue onset (K. Nakayama & M. Mackeben, 1989). Do stimuli from a categorically defined target set, such as letters or digits, also generate transient attention? Participants reported digit targets among keyboard symbols in a changing array of 8 items. When 1 target preceded a second target in the same Location at a stimulus onset asynchrony of 107 ms (but not 213 ms), the second target was reported more often than in a condition in which there was no leading target. When the 2 targets were at different locations, report of the second target was impaired. With both letters and digits as targets, the enhancement effect was shown not to be due to category priming. Critically, the attentional benefit was present whether or not participants reported the leading target. Transient attention, contingent attentional capture, popout, and Lag 1 sparing in the attentional blink may involve a common mechanism for orienting processing resources towards salient and task relevant stimuli. Keywords: transient attention, attentional blink, RSVP, spatial cueing, attentional capture

When asked to identify 2 visual targets (T1 and T2 for the 1st and 2nd targets, respectively) embedded in a sequence of distractors, observers will often fail to identify T2 when it appears within 200-500 ms of T1--an effect called the attentional blink. Recent work shows that attention does not blink when the task is to encode a sequence of consecutive targets, suggesting that distractor interference plays a causal role in the attentional blink. Here, however, the authors show that an attentional blink occurs even in the absence of distractors, with 2 letter targets separated by a blank interval. In addition, the authors found that the impairment for identification of the 2nd of 2 targets separated by a blank interval is substantially attenuated either when the intertarget interval is filled with additional target items or when the 2nd target is precued by an additional target. These findings show that the root cause of the blink lies in the difficulty of engaging attention twice within a short period of time for 2 temporally discrete target events. Keywords: attentional blink, working memory, visual masking, transient attention, sustained attention

Viewers can easily spot a target picture in a rapid serial visual presentation (RSVP), but can they do so if more than 1 picture is presented simultaneously? Up to 4 pictures were presented on each RSVP frame, for 240 to 720 ms/frame. In a detection task, the target was verbally specified before each trial (e.g., man with violin); in a memory task, recognition was tested after each sequence. Target detection was much better than recognition memory, but in both tasks the more pictures on the frame, the lower the performance. When the presentation duration was set at 160 ms with a variable interframe interval such that the total times were the same as in the initial experiments, the results were similar. The results suggest that visual processing occurs in 2 stages: last, global processing of all pictures in Stage 1 (usually sufficient for detection) and slower, serial processing ill Stage 2 (usually necessary for subsequent memory). Keywords: picture perception, picture memory, target detection, RSVP, search

Pictures seen in a rapid sequence are remembered briefly, but most are forgotten within a few seconds (M. C. Potter, A. Staub, J. Rado, & D. H. O'Connor, 2002). The authors investigated the pictorial and conceptual components of this fleeting memory by presenting 5 pictured scenes and immediately testing recognition of verbal titles (e.g., people at a table) or recognition of the pictures themselves. Recognition declined during testing, but initial performance was higher and the decline steeper when pictures were tested. A final experiment included test decoy pictures that were conceptually similar to but visually distinct from the original pictures. Yeses to decoys were higher than yeses to other distractors. Fleeting memory for glimpsed pictures has a strong conceptual component (conceptual short-term memory), but there is additional highly volatile pictorial memory (pictorial short-term memory) that is not tapped by a gist title or decoy picture.

When viewing a rapid sequence of pictures, observers momentarily understand the gist of each scene but have poor recognition memory for most of them (M. C. Potter, 1976). Is forgetting immediate, or does some information persist briefly? Sequences of 5 scenes were presented for 173 ms/picture; when yes-no testing began immediately, recognition was initially high but declined markedly during the 10-item test. With testing delays of 2 or 6 s, the decline over testing was less steep. When 10 or 20 pictures were presented, there was again a marked initial decline during testing. A 2-alternative forced-choice recognition test produced similar results. Both the passage of time and test interference (but not presentation interference) led to forgetting. The brief persistence of information may assist in building a coherent representation over several fixations.

Competition for attention between 2 written words was investigated by presenting the words briefly in a single stream of distractors (Experiment 1) or in different streams (Experiment 2-6), using rapid serial visual presentation at 53 ms/item. Stimulus onset asynchrony (SOA) was varied from 0 to 213 ms. At all SOAs there was strong competition, but which word was more likely to be reported shifted markedly with SOA. At SOAs in the range of 13-53 ms the second word was more likely to be reported, but at 213 ms, the advantage switched to the first word, as in the attentional blink. A 2-stage competition model of attention is proposed in which attention to a detected target is labile in Stage 1. Stage 1 ends when one target is identified, initiating a serial Stage 2 process of consolidation of that target.

A new task, double-word selection, simulated lexical ambiguity by presenting 2 words between which the reader had to choose while reading a sentence shown at 133 or 150 ms/word, following a procedure called rapid serial visual presentation. The double-word pair was presented for less than 100 ms. In immediate recall of the sentence, readers made a correct selection on most trials, both when the relevant context came before the double words and (less accurately) when the relevant context came shortly afterward (Experiments 1 and 2) or with a delay of up to 1 s (Experiment 3). Both words could often be reported if the sentence was stopped one word after the double words (Experiment 2). In Experiment 4, a single function word determined selection between double words differing in syntactic category. The results are consistent with a 2-stage modular interactive model of word perception (M. C. Potter, A. Moryadas, I. Abrams, & A. Noel, 1993) and extend this model to word selection and lexical disambiguation.

When 2 targets are presented among distractors in rapid serial visual presentation, correct identification of the 1st target results in a deficit for a 2nd target appearing within 200-500 ms. This attentional blink (AB; J. E. Raymond, K. L. Shapiro, & K. M. Arnell, 1992) was examined for categorically defined targets (letters among nonletters) in 7 experiments. AB was obtained for the 2nd letter target among digit distractors (Experiment 1) and also for a 3rd target (Experiment 2). Results of Experiments 3-5 confirmed that AB is triggered by local interference from immediate posttarget stimulation (Raymond et al., 1992) and showed that AB is modulated by the discriminability between the 1st target and the immediately following distractor. Experiments 5-7 further examined the effects of both local interference and global discriminability. A 2-stage model is proposed to account for the AB results.

When reading lists of words and nonwords at 100 ms/word, Ss reported words accurately but frequently converted nonwords such as dack into similarly spelled words such as duck or deck. In sentences, both nonwords and anomalous words were misread as appropriate words, but the bias was greater for nonwords. Word associations in lists (e.g., sailor-dack-vessel) produced a similar bias, but when sentence meaning was pitted against such associations the lexical effect was largely overridden. Sentences in which biasing context appeared only after the critical item reduced but did not eliminate the context effect, suggesting that multiple word candidates remained active while at least the next 3 words were processed. These results support a 2-stage modular interactive model: The first stage is stimulus driven and emits multiple weighted candidates that are combined interactively with contextual information in a second stage.

Verbatim short-term memory for a sentence has been taken as evidence for a surface representation different from the conceptual representation characteristic of longer-term memory. In seven experiments we investigated an alternative hypothesis: that immediate recall involves regeneration of the sentence from a conceptual representation, using words that have been recently activated. A key claim is that the activated lexical items are unordered. To test this hypothesis, a synonym of a word in the sentence was presented in a secondary task before or after the sentence, prior to recall. As predicted, these lure words were intruded frequently (Experiments 1 and 2), but only when supported by the meaning of the whole sentence (Experiments 3 and 4). In Experiment 5 as high an intrusion rate was obtained for sentences read in RSVP at 100 ms per word as at the 200 ms rate of the other experiments. Experiment 6 showed that listeners make even more lure-based intrusions than readers. In Experiment 7 4-year-old children made intrusions similar to those of adults. The results support the hypothesis that a sentence is regenerated in immediate recall from a representation of its meaning, using recently activated words. Only when the right set of words is active will recall be 'verbatim'.

Repetition blindness (RB) is the failure to detect or recall repetitions of words in rapid serial visual presentation. Experiment 1 showed that synonym pairs are not susceptible to RB. In Experiments 2 and 3, RB was still found when one occurrence of the word was part of a compound noun phrase. In Experiment 4, homonyms produced RB if they were spelled identically (even if pronounced differently) but not if spelled differently and pronounced the same. Similarly spelled but otherwise unrelated word pairs appeared to generate RB (Experiment 5), but Experiment 6 produced an alternative account. Experiments 7 and 8 demonstrated that repeated letters are susceptible to RB only when displayed individually, not as part of two otherwise different words. It is concluded that RB can occur at either an orthographic (possibly morphemic) level or a case-independent letter level, depending on which unit (words or single letters) is the focus of processing.