Fragmenting pictures on the apple macintosh computer for experimental and clinical applications

A set of procedures implemented in Microsoft BASIC is described that creates fragmented versions of pictures scanned into the Apple Macintosh, stores them as resource files, and presents them in a computerized perceptual memory test. A total of 150 pictures were selected from the Snodgrass and Vanderwart (1980) set for fragmentation. The perceptual memory test provides for five forms of 30 pictures each, divided into two sets of 15 that serve alternately as the training or old set and the new set. A training set of 15 pictures is presented for identification during the first (training) phase of the test. The second (test) phase presents the training pictures again, randomly mixed with 15 new pictures for identification. The performance of 100 subjects on the memory test is presented, along with results for each form. Overall, subjects showed improvement on the task with practice (skill learning), indexed by a decrease in thresholds from the training set to the new set. Subjects also showed large savings for the repeated pictures (perceptual learning), indexed by a decrease in thresholds from the new to the old set.     

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.     

Visual-word recognition thresholds for screen-fragmented names of the Snodgrass and Vanderwart pictures

The set of names corresponding to the pictures from Snodgrass and Vanderwart (1980) were screen fragmented by means of a series of procedures implemented in Microsoft QuickBasic on a Macintosh microcomputer. Words were screen fragmented by deleting blocks of pixels from their images rather than by deleting individual letters. The screen-fragmentation procedure is particularly useful for the present set of words, in which a large proportion of the names of the pictures are short (fewer than five letters). The screen-fragmentation procedure can produce any number of fragmentation levels. In the present implementation, eight levels of fragmented images were produced, to correspond to the eight levels available for the Snodgrass and Vanderwart pictures.     

Does the generation effect occur for pictures?

The generation effect is the finding that self-generated stimuli are recalled and recognized better than read stimuli. The effect has been demonstrated primarily with words. This article examines the effect for pictures in two experiments: Subjects named complete pictures (name condition) and fragmented pictures (generation condition). In Experiment 1, memory was tested in 3 explicit tasks: free recall, yes/no recognition, and a source-monitoring task on whether each picture was complete or fragmented (the complete/incomplete task). The generation effect was found for all 3 tasks. However, in the recognition and source-monitoring tasks, the generation effect was observed only in the generation condition. We hypothesized that absence of the effect in the name condition was due to the sensory or process match effect between study and test pictures and the superior identification of pictures in the name condition. Therefore, stimuli were changed from pictures to their names in Experiment 2. Memory was tested in the recognition task, complete/incomplete task, and second source-monitoring task (success/failure) on whether each picture had been identified successfully. The generation effect was observed for all 3 tasks. These results suggest that memory of structural and semantic characteristics and of success in identification of generated pictures may contribute to the generation effect.     

Visual-word identification thresholds for the 260 fragmented words of the Snodgrass and Vanderwart pictures in Spanish

Word difficulty varies from language to language; therefore, normative data of verbal stimuli cannot be imported directly from another language. We present mean identification thresholds for the 260 screen-fragmented words corresponding to the total set of Snodgrass and Vanderwart (1980) pictures. Individual words were fragmented in eight levels using Turbo Pascal, and the resulting program was implemented on a PC microcomputer. The words were presented individually to a group of 40 Spanish observers, using a controlled time procedure. An unspecific learning effect was found showing that performance improved due to practice with the task. Finally, of the 11 psycholinguistic variables that previous researchers have shown to affect word identification, only imagery accounted for a significant amount of variance in the threshold values.     

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.     

The fate of originally presented surface information following recall errors in sentence memory tasks

Pictures are remembered better than their names. This picture superiority effect in episodic memory has been attributed either to the greater sensory distinctiveness of pictures or to their greater conceptual distinctiveness. Weldon and Coyote (1996) tested the conceptual distinctiveness hypothesis by comparing how well pictures as opposed to words primed in two conceptual implicit memory tasks (category production and word association). They found no picture superiority in priming and concluded that the basis of the picture superiority effect must then be pictures' greater sensory distinctiveness. Using the same logic, we compared how well pictures as opposed to words primed in a perceptual implicit memory task (picture and word fragment identification). The sensory distinctiveness theory would predict that pictures should prime picture fragment identification better than words prime word fragment identification, a result we call the picture superiority in within-form priming. Across three experiments which manipulated the encoding task at study, only one showed picture superiority in within-form priming. In contrast, in all three experiments there was robust picture superiority in recall, and exposure to pictures and words at study and test produced independent effects in which both study and test exposure to pictures was more effective for recall than exposure to words. We consider how these results might be reconciled by differences in retrieval demands between recall and fragment identification.     

A set of 400 pictures standardized for French: Norms for name agreement, image agreement, familiarity, visual complexity, image variability, and age of acquisition

The present article provides French normative measures for 400 line drawings taken from Cycowicz, Friedman, Rothstein, and Snodgrass (1997), including the 260 line drawings that were normed by Snodgrass and Vanderwart (1980). The pictures have been standardized on the following variables: name agreement, image agreement, familiarity, visual complexity, image variability, and age of acquisition. These normative data also include word frequency values and the first verbal associate (taken from Ferrand & Alario, 1998). The six variables obtained are important because of their potential effect in many fields of psychology, especially the study of cognitive processes such as visual perception, language, and memory.     

Naming times and standardized norms for the italian PD/DPSS set of 266 pictures: Direct comparisons with American, English, French, and Spanish published databases

The present study provides Italian normative measures for 266 line drawings belonging to the new set of pictures developed by Lotto, Dell’Acqua, and Job (in press). The pictures have been standardized on the following measures: number of letters, number of syllables, name frequency, within-category typicality, familiarity, age of acquisition, name agreement, and naming time. In addition to providing the measures, the present study focuses on indirect and direct comparisons (i.e., correlations) of the present norms with databases provided by comparable studies in Italian (in which normative data were collected with Snodgrass & Vanderwart’s set of pictures; Nisi, Longoni, & Snodgrass, 2000), in British English (Barry, Morrison, & Ellis, 1997), in American English (Snodgrass & Vanderwart, 1980; Snodgrass & Yuditsky, 1996), in French (Alario & Ferrand, 1999), and in Spanish (Sanfeliu & Fernandez, 1996).     

Enhanced memory for emotional pictures: A product of increased attention to affective stimuli?

The current experiment addressed the question, is enhanced memory for emotional pictures due to increased attention to affective stimuli? Participants viewed pairs of pictures (emotional-neutral or neutral-neutral) whilst their eye movements were recorded; participants had to decide which picture out of each pair they preferred. There was increased attention to positive pictures and decreased attention to negative images during picture viewing. Despite this, when a recognition test was given 1 week later, memory enhancements were found for negative pictures only. Moreover, although there was a general correlation between total inspection time and memory performance, this reliability was clear only for neutral pictures, and not for emotional images. The results suggest that memory advantages for emotional pictures can occur without increased attention to such images.     

The sensory match effect in recognition memory: Perceptual fluency or episodic trace?

The sensory match effect in recognition memory refers to the finding that recognition is better when the sensory form in which an item is tested is the same as that in which it was studied. This paper examines the basis for the sensory match effect by manipulating whether a studied fragmented picture is tested with the same or a complementary set of fragments in a recognition memory test (Experiment 1) and in a fragment-identification test (Experiment 2). Assuming that fragment identification is a direct measure of perceptual fluency, we expected identical patterns of results across the two tests if perceptual fluency accounted for the sensory match effect in recognition memory. Instead, recognition memory showed a robust overall sensory match effect (the same fragmented image was recognized better than the complementary image), whereas fragment identification showed no overall sensory match effect (the same fragmented image was identified no better than the complementary fragmented image). Experiments 3 and 4 combined the two responses and showed that the basis for the sensory match effect in recognition memory was a subject’s ability to recognize the matching fragments in the absence of conceptual information (when the test stimulus could not be identified), supporting the idea that the episodic trace of the sensory code is responsible for the sensory match effect in recognition memory. Experiment 5 demonstrated that subjects are able to use this sensory code as the sole basis for recognition memory.     

L’imagerie bizarre et la mémoire

One experiment examined free recall memory performance for bizarre and common pictures. Bizarre pictures were designed either deleting some components (SB pictures) either adding some components (AB pictures). A classical bizarreness effect was only obtained for AB pictures. Indeed no facilitative effect of bizarreness was obtained when incomplete fragmented pictures were used. Results were discussed in light of theories interested by the explanation of the bizarreness effect in memory.     

False recognition of objects in visual scenes: Findings from a combined direct and indirect memory test

We report an extension of the procedure devised by Weinstein and Shanks (Memory & Cognition 36:1415–1428, 2008) to study false recognition and priming of pictures. Participants viewed scenes with multiple embedded objects (seen items), then studied the names of these objects and the names of other objects (read items). Finally, participants completed a combined direct (recognition) and indirect (identification) memory test that included seen items, read items, and new items. In the direct test, participants recognized pictures of seen and read items more often than new pictures. In the indirect test, participants’ speed at identifying those same pictures was improved for pictures that they had actually studied, and also for falsely recognized pictures whose names they had read. These data provide new evidence that a false-memory induction procedure can elicit memory-like representations that are difficult to distinguish from “true” memories of studied pictures.     

Size and reflection effects in priming: A test of transfer-appropriate processing

Prior research has suggested that priming on perceptual implicit tests is insensitive to changes in stimulus size and reflection. The present experiments were performed to investigate whether size and reflection effects can be obtained in priming under conditions that encourage the processing of this information at study and at test, as predicted by transfer-appropriate processing. The results indicate that priming was affected by a change in the physical size of an object when study and test tasks required a judgment about the real size of pictorial objects (e.g., deciding whether a zebra presented small or large on the screen was larger or smaller than a typical chair), and when the test task required the identification of fragmented pictures. However, a change in left-right orientation had no effect on priming when study and test tasks required a judgment about the left-right orientation of familiar objects, or when the test task involved the identification of fragmented pictures. This difference between size and reflection effects is discussed in terms of the differential importance of size and reflection information in shape identification.     

A cross-culturally standardized set of pictures for younger and older adults: American and Chinese norms for name agreement,concept agreement,and familiarity

The present study presents normative measures for 260 line drawings of everyday objects, found in Snodgrass and Vanderwart (1980), viewed by individuals in China and the United States. Within each cultural group, name agreement, concept agreement, and familiarity measures were obtained separately for younger adults and older adults. For a subset of 57 pictures (22%), there was equivalence in both name agreement and concept agreement, and for an additional subset of 29 pictures (11%), there was nonequivalent name agreement but equivalent concept agreement, across all culture-by-age groups. The data indicate substantial differences across culture-by-age groups in name agreement percentages and number of distinct name responses provided. We discovered significant differences between older and younger American adults in both name agreement percentages (67 pictures, or 26%) and concept agreement percentages (44 pictures, or 17%). Written naming responses collected for the entire set of Snodgrass and Vanderwart pictures showed shifts in both naming and concept agreement percentages over the intervening decades: Although correlations in name agreement were strong (r = .71,p < .001) between our younger American samples and those of Snodgrass and Vanderwart, name agreement percentages have changed for a substantial proportion (33%) of the 260 pictures; moreover, 63% of the stimuli for which Snodgrass and Vanderwart reported concept agreement now appear to differ. We provide comprehensive comparison statistics and tests for both the present study and prior ones, finding differences across numerous item-level measures. The corpus of data suggests that substantial differences in all measures can be found across age as well as culture, so that unequivocal conclusions with respect to cross-cultural or age-related differences in cognition can be made only when appropriate stimuli are selected for studies. Data for all 260 pictures, for each of the four groups, and all supporting materials and tests are freely archived athttp://agingmind.cns.uiuc.edu/Pict Norms. The full set of these norms may be downloaded fromwwwpsychonomic.org/archive/.     

Absolute versus relative difference measures of priming: Which is appropriate when baseline scores change with age?

It is often of theoretical interest to know if implicit memory (repetition priming) develops across childhood under a given circumstance. Methodologically, however, it is difficult to determine whether development is present when baseline performance for unstudied items improves with age. Calculation of priming in absolute (priming=studied – unstudied) or relative‐to‐baseline terms can lead to different conclusions. In first noting this problem, Parkin (1993) suggested using the Snodgrass (1989a) calculation of relative priming [priming=(studied – unstudied)/(maximum – unstudied)], and most developmental studies have since adopted this procedure. Here, we question the Snodgrass method because the Snodgrass method's results are not replicated in the picture identification task when baselines are equated experimentally across age groups. Instead, results support an absolute measure of priming. Theoretically, we argue against its core assumption; namely, that children and adults always lie on the same learning curve, with an equal maximum performance level and equal rate of learning.     

Developmental picture norms: Relationships between name agreement,familiarity, and visual complexity for child and adult ratings of two sets of line drawings

Developmental differences in name agreement, familiarity, and visual complexity in response to line drawings of common objects were obtained from children and adults. Sixty-one pictures were taken from the Peabody Picture Vocabulary Test-Revised and 259 pictures were taken from the set normed for adults by Snodgrass and Vanderwart (1980). Although there were some differences between the two sets of pictures, the present results replicated the relative independence of these three measures, which was reported by Snodgrass and Vanderwart for adults. Children and adults showed substantial agreement on the names of the pictures. Although the children’s ratings were lower on all measures, the differences were trivial for most pictures. We concluded that judgments of familiarity, complexity, and the names of line drawings of common objects are based primarily on information processing accomplished prior to age 7.     

A cross-culturally standardized set of pictures for younger and older adults: American and Chinese norms for name agreement, concept agreement, and familiarity.

The present study presents normative measures for 260 line drawings of everyday objects, found in Snodgrass and Vanderwart (1980), viewed by individuals in China and the United States. Within each cultural group, name agreement, concept agreement, and familiarity measures were obtained separately for younger adults and older adults. For a subset of 57 pictures (22%), there was equivalence in both name agreement and concept agreement, and for an additional subset of 29 pictures (11%), there was nonequivalent name agreement but equivalent concept agreement, across all culture-by-age groups. The data indicate substantial differences across culture-by-age groups in name agreement percentages and number of distinct name responses provided. We discovered significant differences between older and younger American adults in both name agreement percentages (67 pictures, or 26%) and concept agreement percentages (44 pictures, or 17%). Written naming responses collected for the entire set of Snodgrass and Vanderwart pictures showed shifts in both naming and concept agreement percentages over the intervening decades: Although correlations in name agreement were strong (r = .71, p < .001) between our younger American samples and those of Snodgrass and Vanderwart, name agreement percentages have changed for a substantial proportion (33%) of the 260 pictures; moreover, 63% of the stimuli for which Snodgrass and Vanderwart reported concept agreement now appear to differ. We provide comprehensive comparison statistics and tests for both the present study and prior ones, finding differences across numerous item-level measures. The corpus of data suggests that substantial differences in all measures can be found across age as well as culture, so that unequivocal conclusions with respect to cross-cultural or age-related differences in cognition can be made only when appropriate stimuli are selected for studies. Data for all 260 pictures, for each of the four groups, and all supporting materials and tests are freely archived at http://agingmind.cns.uiuc.edu/Pict_Norms. The full set of these norms may be downloaded from www.psychonomic.org/archive/.     

FACTORS INFLUENCING THE IDENTIFICATION OF INCOMPLETE PICTURES BY ZULU CHILDREN

The study examined the identification of pictures at different levels of fragmentation and distinctive feature emphasis by Zulu children from preschool to grade 4. Highly fragmented pictures were found to be more difficult to recognise than less highly fragmented pictures. Enhancing the proportion of line segments devoted to distinctive features had little facilitatory effect on recognition scores until grade 4. A follow-up study examined the effects of previous exposure to different levels of fragmentation and distinctive feature emphasis on the recognition of highly fragmented pictures. This revealed that minimal training was sufficient to improve recognition scores.     

青年人和老年人加工情绪图片过程中的注意偏向:眼动研究

利用眼动追踪技术,考察了老年人与青年人加工情绪图片过程中的注意偏向及再认成绩。给被试同时呈现积极、中性及消极情绪图片,分为注意和记忆两部分任务。基于线性混合模型的分析发现,与青年人相比,老年人表现出对积极图片更大的注意偏向,且在随后的再认过程中对积极情绪图片的再认正确率更高。结果支持了社会情绪选择理论,说明中国老年人同样存在“积极效应”,情绪加工过程中能够通过选择偏爱的积极情绪信息来适应老化。