Spacing effects on the memory for faces

25 undergraduate women studied 12 stimulus pictures of female faces successively presented in spaced or massed conditions and made affective judgments for the pictures along a dimension of like to dislike. One week after the exposure (study) period, subjects were given an identification test comprised of photographs of the same female faces with different expressions. Analysis showed that the pictures presented in the spaced condition were more frequently and accurately identified than those presented under the massed condition and that affective judgment was unrelated to conditions of presentation.     

Spacing effects in recognition memory: When meaning matters

The present study showed that using incidental learning tasks promoting structural/perceptual processing of targets it is possible to obtain a reliable spacing effect for nonwords in a yes/no recognition memory task, whereas no spacing effect is detected for words. These data are, collectively, incompatible with current theories of spacing effects. A theoretical proposal to account for these findings is outlined.     

Spacing and repetition effects in human memory: application of the SAM model

Spacing between study trials of an item increases the probability that item will be recalled. This article presents a new model for spacing based on the SAM theory of memory developed by Raaijmakers and Shiffrin (1980, 1981). The model is a generalization of the SAM model as applied to interference paradigms (Mensink & Raaijmakers, 1988, 1989) and may be viewed as a mathematical version of the Component‐Levels theory proposed by Glenberg (1979). It is assumed that on a second presentation of an item, information is added to an existing trace if the episodic memory image corresponding to that item is retrieved. If it is not retrieved, a new image is stored. It is shown that the model predicts many standard findings including the lack of a spacing effect for the recall of at least one of two items each presented once (Ross & Landauer, 1978).     

Partial picture effects on children's memory for sentences containing implicit information

Two experiments were conducted examining the effects of partial picture adjuncts on young children's coding of information that was implied in sentences. In the two most critical conditions of these studies, subjects were presented sentences specifying a subject, an action, and a direct object with the instrument used to carry out the action not specified in the sentence (e.g., The workman dug a hole in the ground). Implicit-sentence-only subjects received only the sentences, whereas the implicit sentence + partial picture subjects also viewed a partial picture depicting the action in the sentence minus the implied instrument. The main hypothesis was that subsequent recall of the sentences given the implied instrument as a cue would be facilitated by the partial pictures provided at study, since they would lead the children to infer the instrument. That occurred with 6- to 7-year-old children, but not with preschool children. Consistent with the conclusion that the partial pictures prompted 6- to 7-year-olds to infer the instruments, implicit sentence + partial picture subjects recalled as much as subjects in two other conditions, one in which subjects were explicitly told the instruments at study and one in which subjects saw the instruments depicted in pictures at study. In contrast, preschool subjects who heard explicit sentences containing the instruments outperformed subjects who heard implicit sentences even when the implicit sentences were accompanied by pictures depicting the instruments. This failure of complete pictures to facilitate preschoolers' recall of information implied in sentences contrasts with the many demonstrations of prose learning facilitation when picture and sentence contents explicitly and completely overlap. In summary, there were developmental differences in whether (a) partial pictures significantly facilitated inferencing (and subsequent cued recall) and (b) complete pictures containing information not explicitly stated in sentences promoted cued recall of the sentences.     

Organizational factors in picture recognition memory

Since humans have been shown to have a large capacity for dealing with pictures but not for more abstract forms of visual information, it follows that humans must rely on existing mental structures in picture recognition tasks. A series of experiments were designed to examine some characteristics of that structure. The results indicate that something analogous to categories exists for pictures and that when subjects view pictures they tag these categories. The decision in a recognition task that they have or have not seen a picture appears to be based on whether or not an existing category has been tagged. For example, the results indicate subjects can detect a new picture as new with a high degree of certainty. Further, the results show that subjects use information contained in or associated with the new member of the pair in a forced-choice procedure for deciding which member of the pair is old. Since other research has shown that figure-ground ratings made by one group of subjects is a reliable predictor of errors for subjects ranging in age from five to adult, there is evidence that whatever the exact nature of these categories they are not only common between individuals but are established at a very early age.     

The effects of end-of-day picture review and a sensor-based picture capture procedure on autobiographical memory using SenseCam

Emerging "life-logging" technologies have tremendous potential to augment human autobiographical memory by recording and processing vast amounts of information from an individual's experiences. In this experiment undergraduate participants wore a SenseCam, a small, sensor-equipped digital camera, as they went about their normal daily activities for five consecutive days. Pictures were captured either at fixed intervals or as triggered by SenseCam's sensors. On two of five nights, participants watched an end-of-day review of a random subset of pictures captured that day. Participants were tested with a variety of memory measures at intervals of 1, 3, and 8 weeks. The most fruitful of six measures were recognition rating (on a 1-7 scale) and picture-cued recall length. On these tests, end-of-day review enhanced performance relative to no review, while pictures triggered by SenseCam's sensors showed little difference in performance compared to those taken at fixed time intervals. We discuss the promise of SenseCam as a tool for research and for improving autobiographical memory.     

Effectiveness of color in picture recognition memory

Investigations were conducted into the effectiveness of color in picture recognition memory. In the study phase, half of the pictures were presented in color and the other half in black and white. In the test phase, half were presented in the same color mode as the study pictures and the other half in the other mode. In immediate and 1-week-delayed tests, the recognition performance was highest when color pictures were used in both the study and test phases. The recall for the color mode of the study pictures, however, was not as good, even with the color pictures. This suggests that the effectiveness of color in picture recognition is not necessarily due to the memory for colors in the pictures themselves, but is probably due to the distinctiveness of features highlighted by the colors. We also found that in the recall performance for the color mode it was more difficult to detect the deletion of colors than to detect their addition.     

Two types of information in picture memory.

It is assumed that recognition memory for pictures is based on two types of information. The first is information about specific details in a picture. The process of encoding this type of information is identified with what N. H. Mackworth and others have termed looking at "informative areas" in pictures. The second informational component is designated as "general visual information." Two experiments were carried out investigating (a) the extent to which recognition responses to pictures are based on specific detail vs. general visual information, (b) whether the amount of specific detail information may be manipulated by varying the complexity of a target picture, and (c) the rate at which the two types of information are acquired. The results indicate that the rate of encoding specific details varies with the number of potential informative areas in a pictures and, given that a detail is encoded, memory performance is not substantially affected by target complexity, exposure time, or presence or absence of a mask.     

Category-structure effects in picture comparisons

Subjects indicated for a series of trials whether or not two pictures of common objects were from the same category. Reaction time (RT) was recorded. The pool of stimuli used in the series of trials consisted of two pictures representing each of several categories. Half were S categories, members of which were similar; the other half were D categories, which had dissimilar members (this variable is termed category structure). In Experiments 1 and 3, the similarity manipulation defining category structure was based on the concept of basic level categories (Rosch, Mervis, Gray, Johnson, & Boyes-Braem, 1976). In Experiment 2, category labels were homonyms, and the two members of S or D categories represented one or two senses of the labels, respectively. The principal finding was an effect of category structure (faster RT on trials using stimuli from S categories rather than D categories). These results are interpreted in terms of a model that postulates the use of semantic codes in the task, even on trials where the two stimuli are physically identical.     

Conceptual memory for picture and prose episodes

In two experiments, subjects decided whether probes were true or false of one of some previously studied picture and prose episodes. The results indicated that response times to probes depicting explicit events were faster when they were in the same modality (picture or prose) as their episodes than when they were in the opposite modality, but response times to probes depicting implicit events were as fast when they were in the opposite modality as when they were in the same modality. These results suggest that the conceptual representations of picture and prose episodes are identical in form. The second experiment indicated that probes could be evaluated as fast from long as from short episodes. This result is consistent with the notion that retrieving information from episodes is done, not by scanning all the events of an episode, but by restricting the search only to the relevant slot in the schema into which the episode is assimilated.     

A signal-to-noise theory of the effects of luminance on picture memory: comment on Loftus

In studies of picture memory, subjects typically view a sequence of pictures. Their memory is tested either after each picture is presented (short-term recall) or at the end of the sequence (long-term recall). The increase in performance as a function of picture viewing time defines "the rate of information acquisition." Loftus (1985) found that reducing the luminance of a picture reduces the rate at which information is acquired (for both short-term and long-term tests) and, for long viewing times, reduces the total amount of recall. The theory proposed here assumes that both of these effects are consequences of intrinsic noise in the visual system that becomes relatively more prominent as signal (picture luminance or contrast) is reduced. Noise shares a limited capacity channel with signal, and thus noise reduces the rate of information acquisition; noise, as well as signal, occupies space in memory, and thus noise reduces recall performance.     

Working memory capacity and dual-task interference in picture naming

Researchers have found no agreement on whether dual-task interference in language performance, such as dual-task interference from tone discrimination on picture naming, reflects passive queuing or active scheduling of processes for each task. According to a passive-queuing account, while a central response-selection bottleneck is occupied by the tone discrimination task, picture naming is held in a passive queue until the bottleneck is freed. In contrast, according to an active-scheduling account, participants determine the order in which the tasks proceed, monitor progress on the tasks, suspend picture naming and hold it in working memory, and determine when to resume picture naming. Here, we report a study that assessed the relative merits of the queuing and scheduling accounts by examining whether the magnitude of dual-task interference in picture naming is associated with individual differences in the capacity of monitoring and updating of working memory representations, as assessed by the operation-span task. We observed that the updating/monitoring ability correlated with the speed of picture naming and with the magnitude of the interference from tone discrimination on picture naming. These results lend support to the active-scheduling account of dual-task interference in picture naming.     

Gender congruency effects in picture naming

The analysis of speech error corpora in various gender-marked languages has shown that noun substitutions tend to preserve grammatical gender. This result has been taken as an indication that grammatical gender could play a constraining role during the process of lexical selection. To gain insights on the status of grammatical gender in the speech production system, we discuss this hypothesis and we report three picture naming experiments. We attempted to observe gender-marked context effects in the course of error-free speech production. Participants named pictures shortly after processing a prime that was or was not gender marked and that was or was not congruent with the name of the picture. A clear congruency effect was observed, involving both facilitation in the gender congruent conditions and inhibition in gender incongruent conditions. Different interpretations of this effect and of previously reported gender context effects are discussed in the context of current models of speech production.     

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.     

Simultaneous manipulation of propositional and analog codes in picture memory

Revealing a picture as a whole or as momentarily displayed strips presumably manipulated the propositional coding of the picture. Analog manipulation employed superimposition of a grid pattern. Effectiveness of simultaneous manipulations was tested via recognition with three foil categories, each of which presumably tapped the analog or propositional codes mainly, or both of them in detection. While figural units' perspective reversals should presumably be detected via the analog code, their locational displacements should be detected via the propositional code. Foils with novel item substitution should be detected by both codes. On the basis of such presumptions about encoding and recognition manipulations, certain predictions were made for scan and grid effects in "reversal," "displacement," and "novelty" foil categories. Full confirmation of these predictions was then taken as evidence that both analog and propositional codes do exist. Once such evidence was established, other issues were tackled, showing that target detection involves the propositional code only, while foil detection involves both codes. Further, recognition hypermnesia, where performance improves with repeated testing, was obtained only when both codes were attenuated. Data suggested that subjects might be switching from analog to propositional codes when both codes were strong, thereby preventing hypermnesia.     

Verifying visual properties in sentence verification facilitates picture recognition memory

According to the perceptual symbols theory (Barsalou, 1999), sensorimotor simulations underlie the representation of concepts. We investigated whether recognition memory for pictures of concepts was facilitated by earlier representation of visual properties of those concepts. During study, concept names (e.g., apple) were presented in a property verification task with a visual property (e.g., shiny) or with a nonvisual property (e.g., tart). Delayed picture recognition memory was better if the concept name had been presented with a visual property than if it had been presented with a nonvisual property. These results indicate that modality-specific simulations are used for concept representation.     

Developmental differences in the role of detail in picture recognition memory

Two experiments assess the effect of the amount of physical detail in pictures on picture recognition memory. Children and adults were presented simple and complex line drawings. A “same-different” recognition test followed in which the distractor items were original pictures from the presentation phase with the amount of physical detail altered. For second- and fourth-grade subjects, recognition sensitivity, measured in terms of d′, was similar for pictures in the simple and complex presentation conditions. For adults, however, recognition sensitivity was greater for pictures in the simple than complex presentation condition. This finding with adults was replicated in Experiment 2. Interpretations of this age difference in picture memory processing are discussed, as well as the constraints imposed by various dependent measures used in picture memory studies.     

Visual effects in picture and word categorization

Two experiments are reported in which participants categorized stimuli as belonging or not belonging to the category of fruits. Blocks of pictures and words were used, with items referring to exemplars having either high or low intercategory visual similarity and/or semantic relatedness. For both pictures and words, response time was longer in the semantically related conditions than in the unrelated condition. Furthermore, there was a strong effect of visual similarity for pictures but not for words when semantic relatedness was held constant: Participants took longer to classify pictures of fruits when these were mixed with visually similar vegetables than when they were mixed with visually dissimilar vegetables. Reducing the stimulus visibility by adding a dot pattern had an additive effect for words but an interactive effect for pictures. The results are explained in terms of a unique locus for category decisions about pictures and words.     

Orientation-specific effects in picture matching and naming

In two experiments, subjects made timed decisions about the second of two sequentially presented rotated drawings of objects. When the two objects were physically identical, response times to decide whether the two drawings depicted the same object varied as a function of the shortest distance between the orientation of the second drawing and either the orientation of the previous drawing or the upright. This was found for both short (250-msec) and long (2-sec) interstimulus-intervals. The result was also obtained when subjects named the second drawing after deciding whether the first drawing faced left or right. Following repeated experience with the drawings in the left/right task over four blocks of trials, time to name the second drawing in the same-object sequences was independent of orientation. These results suggest that, initially, object- and orientation-specific representations can be formed following a single presentation of a rotated object and subsequently used to identify drawings of the same object at either the same or different orientations. Alignment of the second drawing with either the canonical representation or the new representation at the previous orientation is achieved by normalization through the shortest path. Following experience with the objects, orientation-invariant representations are formed.