Accurate identification but no priming and chance recognition memory for pictures in RSVP sequences

In 1969, Potter and Levy reported that recognition memory of accurately perceived RSVP pictures was extremely low, an effect that they attributed to disruption of memory consolidation. Here we report that the repetition of an RSVP picture (72-126 msec/picture) up to 31 times prior to when it became a target had no effect on identification accuracy. At these rates, forced-choice recognition memory was at chance. Single presentations of the pictures outside of the RSVP sequences readily resulted in substantial priming of their identification within the sequences. We offer a neural interpretation of Potter and Levy's explanation, as well as contemporary two-stage accounts of RSVP memory and attentional phenomena, based on the recent finding (Tovee & Rolls, 1995) that most of the information in inferior temporal cells is conveyed in the first 50msec of firing but the cells continue their activity for an additional 350msec. The additional activity, by our account, is required for memory and it is this activity that may be disrupted by attention to the next image during RSVP presentations. The critical factor for priming, if not memory in general, may be attention to the stimulus for a few hundred milliseconds beyond that required for its identification. Single-trial presentations thus manifest robust memory and priming effects - even when the stimulus cannot be identified - whereas RSVP conditions in which the stimulus can be identified result in poor memory.     

Integrating pictorial information across eye movements

Six experiments are reported dealing with the types of information integrated across eye movements in picture perception. A line drawing of an object was presented in peripheral vision, and subjects made an eye movement to it. During the saccade, the initially presented picture was replaced by another picture that the subject was instructed to name as quickly as possible. The relation between the stimulus on the first fixation and the stimulus on the second fixation was varied. Across the six experiments, there was about 100-130 ms facilitation when the pictures were identical compared with a control condition in which only the target location was specified on the first fixation. This finding clearly implies that information about the first picture facilitated naming the second picture. Changing the size of the picture from one fixation to the next had little effect on naming time. This result is consistent with work on reading and low-level visual processes in indicating that pictorial information is not integrated in a point-by-point manner in an integrated visual buffer. Moreover, only about 50 ms of the facilitation for identical pictures could be attributed to the pictures having the same name. When the pictures represented the same concept (e.g., two different pictures of a horse), there was a 90-ms facilitation effect that could have been the result of either the visual or conceptual similarity of the pictures. However, when the pictures had different names, only visual similarity produced facilitation. Moreover, when the pictures had different names, there appeared to be inhibition from the competing names. The results of all six experiments are consistent with a model in which the activation of both the visual features and the name of the picture seen on the first fixation survive the saccade and combine with the information extracted on the second fixation to produce identification and naming of the second picture.     

Change detection: evidence for information accumulation in flicker paradigms

Change detection in rapidly alternating pictures separated by a blank frame has been shown to be very difficult (e.g., [Rensink, R. A., O'Regan, J. K., & Clark, J. J. (1997). To see or not to see: The need for attention to perceive changes in scenes. Psychological Science, 8, 368-373]). The three experiments reported here focus on the mechanism behind detection. More specifically, we explored whether information about the stimulus material accumulates in visual memory and thereby improves change detection. For that purpose the first experiment varied the number of repetitions of the original and modified stimulus version. Results showed that detection improved with more repetitions. The second experiment demonstrated that repetition performance improved more when both the original and the modified picture were repeated. Finally, the third experiment strengthened these findings by showing poorer detection performance when the repetition sequence was randomized. Together, our findings suggest accumulation of information in memory over picture presentations and moreover improved performance when both picture types were repeated. These results underline the importance of developing representations for both picture versions in change detection.     

Perceptual identification thresholds for 150 fragmented pictures from the Snodgrass and Vanderwart picture set

This paper reports perceptual identification thresholds for 150 pictures from the 1980 Snodgrass and Vanderwart picture set. These pictures were fragmented and presented on the Apple Macintosh microcomputer in a picture-fragment completion task in which identification thresholds were obtained at three phases of learning: Train (initial presentation), New (initial presentation after training on a different set), and Old (repeated presentation of the Train set). Pictures were divided into five sets of two subsets of 15 pictures each, which served alternately as the Train and New sets. A total of 100 subjects participated in the task, with 10 subjects assigned to each subset. Individual thresholds for each picture at each phase of learning are presented, along with the fragmented pictures identified by 35% of the subjects across the Train and New learning phases. This set of fragmented pictures is provided for use in experiments in which a single level of fragmented image is presented for identification after a priming phase. Correlations between the Snodgrass and Vanderwart norms and identification thresholds at the three phases of learning are also reported.     

How much is an icon worth?

We report a new technique for assessing the amount of information extracted from the icon that follows a briefly presented picture. The problem of how to measure such information was formulated in terms of how much physical exposure of a picture an icon is worth. Consider two types of stimulus presentations, each with a base duration of d ms. The first is a d-ms picture followed by an icon, and the second is a d + a-ms picture not followed by an icon. How large does a have to be so that equivalent amounts of information are extracted in the two cases? To answer this question, we showed people pictures and later tested their memory for the pictures. We found that the physical exposure duration needed to reach a particular level of performance was approximately 100 ms longer when an icon was not permitted versus when the icon was permitted. This value was independent of the base duration and the luminance of the picture. Moreover, the same value was obtained using three different kinds of memory test and four different sets of pictures. We conclude that an icon is worth approximately 100 ms of additional physical exposure duration. A reasonable explanation for this robust equivalence between icon and stimulus is that the same encoding processes are responsible for extracting information from the icon and from the physical stimulus. Therefore, any variable that affects these encoding processes must affect extraction of information from the icon and the physical stimulus in an identical manner. This prediction was confirmed for one such variable, picture luminance.     

The Defence Mechanism Test (DMT) revisited: experimental validation using threatening and non‐threatening pictures

Although the Defence Mechanism Test (DMT) has been in use for almost half a century, it is still unclear what it actually measures. The psychodynamic theory on which the test is based states that the threatful DMT pictures activate various defence mechanisms. To test this proposition, the original DMT pictures were redrawn by a professional artist, changing the emotional content without altering the structural properties. In this way, a neutral and a friendly variant were shaped. Sixty participants were randomly assigned to the threatful, neutral, and friendly stimulus conditions. In contrast to predictions made from psychodynamic theory, that the threatful picture would activate more ‘signs of defence’ than the others, the results disclosed that the three conditions activated the same amounts of ‘signs of defence’ and the same levels of various perceptual thresholds. Thus, rather than capturing psychodynamic defence mechanisms, our results suggest that the DMT taps perceptual or information‐processing difficulties in correct identification of brief stimulus exposures regardless of their emotional contents. Copyright © 2002 John Wiley & Sons, Ltd.     

Detecting meaning in RSVP at 13 ms per picture

The visual system is exquisitely adapted to the task of extracting conceptual information from visual input with every new eye fixation, three or four times a second. Here we assess the minimum viewing time needed for visual comprehension, using rapid serial visual presentation (RSVP) of a series of six or 12 pictures presented at between 13 and 80 ms per picture, with no interstimulus interval. Participants were to detect a picture specified by a name (e.g., smiling couple) that was given just before or immediately after the sequence. Detection improved with increasing duration and was better when the name was presented before the sequence, but performance was significantly above chance at all durations, whether the target was named before or only after the sequence. The results are consistent with feedforward models, in which an initial wave of neural activity through the ventral stream is sufficient to allow identification of a complex visual stimulus in a single forward pass. Although we discuss other explanations, the results suggest that neither reentrant processing from higher to lower levels nor advance information about the stimulus is necessary for the conscious detection of rapidly presented, complex visual information.     

无意识信息加工中的“完型”——无意识捆绑假说的新证据

采用连续闪烁范式(Continuous Flash Suppression,CFS)考察了无意识状态下完型能否发生.研究通过2(线条完整性)×2(意义破坏)×2(熟悉性)的被试内实验设计考察了8种条件下图片的突破抑制时间(Suppression Time,ST).结果发现:线条完整和意义未破坏的图片能更快地克服噪音图片的抑制进入意识;熟悉性不影响突破抑制时间.重要的是,不完整的图片也可以出现意义破坏效应.这表明即使在被抑制的状态下,不完整图形的信息也能够传达至与完型相关的高级视觉区域形成客体表征.研究为无意识捆绑假说(The Unconscious Binding Hypothesis)提供了新的实验证据.     

When hearing the bark helps to identify the dog: Semantically-congruent sounds modulate the identification of masked pictures

We report a series of experiments designed to assess the effect of audiovisual semantic congruency on the identification of visually-presented pictures. Participants made unspeeded identification responses concerning a series of briefly-presented, and then rapidly-masked, pictures. A naturalistic sound was sometimes presented together with the picture at a stimulus onset asynchrony (SOA) that varied between 0 and 533 ms (auditory lagging). The sound could be semantically congruent, semantically incongruent, or else neutral (white noise) with respect to the target picture. The results showed that when the onset of the picture and sound occurred simultaneously, a semantically-congruent sound improved, whereas a semantically-incongruent sound impaired, participants’ picture identification performance, as compared to performance in the white-noise control condition. A significant facilitatory effect was also observed at SOAs of around 300 ms, whereas no such semantic congruency effects were observed at the longest interval (533 ms). These results therefore suggest that the neural representations associated with visual and auditory stimuli can interact in a shared semantic system. Furthermore, this crossmodal semantic interaction is not constrained by the need for the strict temporal coincidence of the constituent auditory and visual stimuli. We therefore suggest that audiovisual semantic interactions likely occur in a short-term buffer which rapidly accesses, and temporarily retains, the semantic representations of multisensory stimuli in order to form a coherent multisensory object representation. These results are explained in terms of Potter’s (1993) notion of conceptual short-term memory.     

A funny thing happened on the way to articulation: N400 attenuation despite behavioral interference in picture naming

We measured Event-Related Potentials (ERPs) and naming times to picture targets preceded by masked words (stimulus onset asynchrony: 80 ms) that shared one of three different types of relationship with the names of the pictures: (1) Identity related, in which the prime was the name of the picture ("socks" - ), (2) Phonemic Onset related, in which the initial segment of the prime was the same as the name of the picture ("log" - ), and (3) Semantically related in which the prime was a co-category exemplar and associated with the name of the picture ("cake" - ). Each type of related picture target was contrasted with an Unrelated picture target, resulting in a 3×2 design that crossed Relationship Type between the word and the target picture (Identity, Phonemic Onset and Semantic) with Relatedness (Related and Unrelated). Modulation of the N400 component to related (versus unrelated) pictures was taken to reflect semantic processing at the interface between the picture's conceptual features and its lemma, while naming times reflected the end product of all stages of processing. Both attenuation of the N400 and shorter naming times were observed to pictures preceded by Identity related (versus Unrelated) words. No ERP effects within 600 ms, but shorter naming times, were observed to pictures preceded by Phonemic Onset related (versus Unrelated) words. An attenuated N400 (electrophysiological semantic priming) but longer naming times (behavioral semantic interference) were observed to pictures preceded by Semantically related (versus Unrelated) words. These dissociations between ERP modulation and naming times suggest that (a) phonemic onset priming occurred late, during encoding of the articulatory response, and (b) semantic behavioral interference was not driven by competition at the lemma level of representation, but rather occurred at a later stage of production.     

Cognitive masking in rapid sequential processing: The effect of an emotional picture on preceding and succeeding pictures

This experiment assessed the effect of an emotional pictorial input on the processing of preceding and succeeding pictorial inputs. Thirty-nine individual pictures were successively presented for 165 msec, with a 500-msec dark interval between each item. The 20th input item was either an emotional or a neutral picture; the remaining 38 items were neutral sketches. Postinput recognition data indicated a processing disruption of several pictorial items following the emotional as compared to the neutral input and a possible processing disruption of the item immediately preceding the emotional stimulus. The outcome suggests nonindependence in the processing of separate picture inputs in rapid sequential presentations.     

Conceptual priming with pictures and environmental sounds

A series of experiments was conducted to examine conceptual priming within and across modalities with pictures and environmental sounds. In Experiment 1, we developed a new multimodal stimulus set consisting of two picture and sound exemplars that represented 80 object items. In Experiments 2, we investigated whether categorization of the stimulus items would be facilitated by picture and environmental sound primes that were derived from different exemplars of the target items; and in Experiments 3 and 4, we tested the additional influence on priming when trials were consolidated within a target modality and the inter stimulus interval was lengthened. The results demonstrated that target categorization was facilitated by the advanced presentation of conceptually related exemplars, but there were differences in effectiveness when pictures and sounds appeared as primes.     

Picture book exposure elicits positive visual preferences in toddlers

Although the relationship between “mere exposure” and attitude enhancement is well established in the adult domain, there has been little similar work with children. This article examines whether toddlers’ visual attention toward pictures of foods can be enhanced by repeated visual exposure to pictures of foods in a parent-administered picture book. We describe three studies that explored the number and nature of exposures required to elicit positive visual preferences for stimuli and the extent to which induced preferences generalize to other similar items. Results show that positive preferences for stimuli are easily and reliably induced in children and, importantly, that this effect of exposure is not restricted to the exposed stimulus per se but also applies to new representations of the exposed item.     

Semantic priming effects on picture and word processing

The effects of semantic priming on picture and word processing were assessed under conditions in which subjects were required simply to identify stimuli (label pictures or read words) as rapidly as possible. Stimuli were presented in pairs (a prime followed by a target), with half of the pairs containing members of the same semantic category and half containing unrelated concepts. Semantic relatedness was found to facilitate the identification of both pictures (Experiment 1) and words (Experiment 2), and obtained interactions of semantic relatedness and stimulus quality in both experiments suggested that semantic priming affects the initial encoding of both types of stimuli. In Experiment 3, subjects received pairs of pictures, pairs of words, and mixed pairs composed of a picture and a word or of a word and a picture. Significant priming effects were obtained on mixed as well as unmixed pairs, supporting the assumption that pictures and words access semantic information from a common semantic store. Of primary interest was the significantly greater priming obtained in picture-picture pairs than in word-word or mixed pairs. This suggests that, in addition to priming that is mediated by the semantic system, priming may occur in picture-picture pairs that results from the overlap in visual features common to the pictorial representations of objects from the same semantic category.     

Infants' discrimination of photographs of faces following redundant presentations

Infants' discrimination of photographs of faces, as indicated by fixation toward novel targets, was the criterion used to evaluate familiarization conditions designed to facilitate the exercise of selective attention. Groups of 19- and 23-week-old infants were shown either pictures of different faces of the same sex, differing poses of the same face, or repeated exposures of the face that served as a test stimulus. The older infants demonstrated differential attention to novel over familiar stimuli during subsequent recognition tests, and an examination of their responsiveness during familiarization presentations indicated differing trends of looking activity.     

Pre-extinction of sensory preconditioned electrodermal activity

In the present study, sensory preconditioning of human electrodermal activity was demonstrated. In the first phase of the experiment, two pairs of neutral pictures of human faces were presented (A/B and C/D) sequentially. In the second phase, one picture of one pair was immediately followed by an electrocutaneous stimulus (B+), and one picture of the other pair was not (D-). In the third phase the other picture of each pair (A and C) was tested. The effect of A and C alone presentations (pre-extinction) between the first and the second phase was investigated. When only those participants that showed reliable B+/D- differentiation were considered, the extinction group did not show stronger conditioned electrodermal activity to A than to C, whereas the control group did. These findings suggest that sensory preconditioning of anticipatory/preparatory responding only occurs when the pre-conditioned stimulus (A) actually predicts the conditioned stimulus (B).     

How the social-evaluative context modulates processes of cognitive control

Cognitive control enables intelligent systems to select relevant information in the face of distracting information. The aim of the research presented here was to investigate the influence of the social-evaluative context on processes of cognitive control. Female participants had to perform the Erikson flanker task with each trial being preceded by a photograph of an attractive woman or a beautiful landscape. Concurrently, another person (partner or fellow student) either evaluated the attractiveness of the pictures of the women or the beauty of the landscapes. Participants showed increased flanker interference on trials following the presentation of pictures of attractive women, but only, if these were concurrently evaluated by another person. By contrast, in the control conditions (social presence without concurrent picture evaluation, or picture evaluation without social presence) no such effect occurred. That is, the concurrent evaluation task selectively increased distractibility presumably due to the affective reaction to the social-evaluative context.     

Episodic effects on picture identification: implications for theories of concept learning and theories of memory

The effects of differences in study processing on free recall of picture names and on generalization in picture identification were investigated. Experience with degraded pictures produced poorer subsequent free recall of picture names than did naming intact pictures. For the test of picture identification, pictures that were identical to a studied picture, pictures that shared a name with a studied picture (same name), and new test pictures were presented, and the amount of clarification required to identify a picture was measured. Experience with degraded pictures produced better subsequent identification of identical test pictures but poorer later identification of same-name test pictures than did naming intact pictures. The importance of these episodic effects for theories of concept learning and theories of memory is discussed. It is argued that distinctions between memory systems (e.g., episodic-semantic) must be couched in terms of a theory of concept learning and that the data are inconsistent with a simple distinction.