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Biomedical subjects

A Koriat

Publications and source records attributed to A Koriat.

At least 19 recordsLinked to original sources
PubMed1994

Memory in naturalistic and laboratory contexts: distinguishing the accuracy-oriented and quantity-oriented approaches to memory assessment.

A distinction is drawn between the quantity-oriented approach to memory that has dominated traditional laboratory research, and the accuracy-oriented approach that is emerging in the study of everyday memory. This distinction is shown to underlie some troubling confusions in the interpretation of empirical findings. In particular, the recall-recognition paradox, which involves the claimed superiority of recall over recognition memory in naturalistic settings, is shown to stem from the common confounding between memory property (quantity vs. accuracy) and 2 other variables that have not generally been distinguished--test format (production vs. selection) and report option (free vs. forced reporting). Three laboratory experiments reveal the fundamentally different roles played by report option and test format in accuracy-based and quantity-based memory research. Implications for memory assessment, metamemory, and the everyday-laboratory controversy are discussed.

Female↗
PubMed1994

Object-based apparent motion.

The interpretation of a dynamic visual scene requires integrating information within frames (grouping and completion) and across frames (correspondence matching). Fragmentary views of objects were used in five experiments. These views could not be matched with each other by any similarity transformation on the basis of their explicit visual features, but their completed versions were related by a rotational transformation. When the fragmentary images were successively presented to observers, it was found that they produced apparent motion in the picture plane and in depth. Thus, apparent motion is capable of establishing correspondence at the level of perceptually recovered objects in three-dimensional space.

Depth Perception↗
PubMed1993

How do we know that we know? The accessibility model of the feeling of knowing.

Even when Ss fail to recall a solicited target, they can provide feeling-of-knowing (FOK) judgments about its availability in memory. Most previous studies addressed the question of FOK accuracy, only a few examined how FOK itself is determined, and none asked how the processes assumed to underlie FOK also account for its accuracy. The present work examined all 3 questions within a unified model, with the aim of demystifying the FOK phenomenon. The model postulates that the computation of FOK is parasitic on the processes involved in attempting to retrieve the target, relying on the accessibility of pertinent information. It specifies the links between memory strength, accessibility of correct and incorrect information about the target, FOK judgments, and recognition memory. Evidence from 3 experiments is presented. The results challenge the view that FOK is based on a direct, privileged access to an internal monitor.

Adult↗
PubMed1992

The effects of syntactic structure on letter detection in adjacent function words.

In the present study, we examined letter detection in very frequent function-word sequences. It has been claimed that such sequences are processed in a unitized manner, thus preempting access to their constituent letters. In contrast, we showed that letter detection in the words for and the (1) was no more difficult when the words appeared in adjacent locations in a sentence (familiar) than when they appeared apart (less familiar sequence) and (2) was contingent upon the words' syntactic roles within the phrase. Thus, letter detection in for was easier when the sequence was separated by a clause boundary than when the words were part of the same clause. The advantage derived from clause separation was strongest when a comma divided clauses. These results challenge the unitization account of the "missing-letter" effect in common phrases and support a position where this phenomenon is seen to reflect the extraction of phrase structure during reading.

Adult↗
PubMed1991

Recognition of rotated letters: extracting invariance across successive and simultaneous stimuli.

Response time (RT) for identifying single letters is usually indifferent to disorientation, but in Experiment 1 RT increased with the angular deviation from that of the preceding letter (ADP). This occurs only when the same letter is repeated, which suggests a process of backward alignment. RT again increased with ADP when the same letter was repeated in the same format (normal or mirror-reflected: Experiment 2). These findings were replicated for a same-different task by using 2 simultaneously presented letters (Experiment 3). Experiments 4 and 5 focused on stimuli that are related by a rotation in depth and suggested that transformation in the depth plane may facilitate judgments of sameness and that backward alignment can occur for different views of the same three-dimensional shape. The results suggest the operation of a pattern-recognition mechanism that relies on the extraction of invariance over temporally or spatially contiguous events.

Adult↗
PubMed1990

Encoding information for future action: memory for to-be-performed tasks versus memory for to-be-recalled tasks.

What is the nature of the representation underlying memory for future tasks such as calling the doctor or buying milk? If this representation consists of a verbal instruction that is translated into action at the time of retrieval, then memory should be better when tested via verbatim recall of the instruction than when tested via actual performance. Three experiments rejected this possibility, indicating better memory for a perform mode of report than for a recall mode of report. This was true in Experiment 1 in which subjects saw a series of verbal instructions (e.g., "move the eraser," "lift the cup," "touch the ashtray"), with advance information regarding the mode of report required during testing. In Experiment 2, the advance cue was valid only in 75% of the trials. Memory depended more heavily on the expected mode of report than on the actual mode of report, suggesting that the perform superiority is due to processes that occur during encoding. In Experiment 3, subjects learned 20 phrases depicting minitasks. More tasks were remembered by subjects tested via performance than by subjects tested via verbatim recall. A second part of Experiment 3 also indicated superior memory when a perform test was expected, regardless of which mode of report was actually required. The results were compared with the finding that subject-performed tasks are better remembered than are their verbal instructions, which suggests that the representation underlying memory for future assignments may take advantage of the imaginal-enactive properties of the envisaged acts. Other possible differences between memory for to-be-recalled tasks and memory for to-be-performed tasks are discussed.

Adolescent↗
PubMed1989

Why is word recognition impaired by disorientation while the identification of single letters is not?

Past research has shown that speed of identifying single letters or digits is largely indifferent to orientation, whereas the recognition of single words or connected text is markedly disrupted by disorientation. In a series of four experiments, we attempted to reconcile these findings. The results suggest that disorientation does not impair the identification of the characters but disrupts the perception of their spatial arrangement. When spatial order information is critical for distinguishing between different stimuli, disorientation is disruptive because some rectification process is required to restore order information. Utilizing the similarity between the letter B and the number 13, we found strong effects of orientation when a stimulus was interpreted as the two-digit number 13 but not when interpreted as the single letter B. This, however, occurred only when the set of numbers to be classified included permutations of the same digits (Experiments 1 and 2). Odd-even decisions on single-digit and two-digit numbers (Experiment 3) yielded strong effects of stimulus orientation for order-dependent numbers (e.g., 32), weaker effects for order-independent numbers (e.g., 24), and none for repeated-digit (e.g., 22) or single-digit numbers. Classification time for two-letter Hebrew words evidenced strong effects of orientation for words that differed only in letter order but much weaker effects for words that had no letters in common, even when these were embedded within some words that did (Experiment 4).

Adult↗
PubMed1989

Establishing global and local correspondence between successive stimuli: the holistic nature of backward alignment.

Reflection decisions on alphanumeric characters display systemic effects of disorientation, suggesting that subjects mentally rotate the stimulus to the upright (the uprighting process). However, response time also increases with increasing angular disparity between the current and preceding orientations. This occurs only when the current stimulus is brought into congruence with the preceding one (the backward alignment process). In the present study, we examined the hypothesis that the transformation that occurs in backward alignment in holistic even in tasks in which the uprighting process is likely to be piecemeal. Evidence supporting this hypothesis is presented on the basis of tasks requiring either classification of numbers (Experiments 1 and 3) and words (Experiment 2), or mirror image discrimination on letter pairs (Experiment 4). The results indicated that backward alignment establishes global correspondence between successive stimuli and is indifferent to local correspondence at the level of the constituent elements. The establishment of this global correspondence decreases with the number of elements in the stimulus (Experiment 5), but its effects are still observed for four-letter strings (Experiment 6).

Adult↗
PubMed1988

Frames and images: sequential effects in mental rotation.

Recent studies have shown that response time in mental rotation increases with the angular deviation between the current and preceding stimuli, suggesting a frame rotation process in which the intrinsic frame of the previous stimulus is brought into congruence with the coordinates of the current stimulus. In contrast, we show that this process involves image rotation in which the present stimulus is brought into alignment with the orientation of the previous stimulus. Such "backward alignment" succeeds only for shape-preserving sequences (i.e., identical stimuli at different orientations). Four experiments show that the backward alignment process (a) competes with the uprighting process typically found in mental rotation, and the response is determined by the process requiring the shortest rotational path; (b) is related to the tendency to repeat the previous response; (c) is insensitive to the position of the vertical; (d) is indifferent to the representation of the stimulus in long term memory; and (e) is different from the process underlying preparation for a stimulus in a specified orientation.

Attention↗
PubMed1985

Reading rotated words.

Hebrew-speaking students performed lexical decisions on Hebrew letter strings that appeared at different orientations. Response times evidenced a strong interaction between string length and orientation. At angular deviations of less than 60 degrees from the upright, neither orientation nor string length had any effect, suggesting that words were directly, and probably holistically, recognized. The results for the 60 degrees deviation, while also exhibiting no effects of word length, yielded slower response times, suggesting a holistic rectification process. For deviations between 60 degrees and 120 degrees, the effects of disorientation increased sharply with increasing string length, suggesting piecemeal processing that may be due to the utilization of reading units smaller than the whole word or to piecemeal rectification. In this region, stimulus disorientation appears to impair word recognition by disrupting transgraphemic information rather than by interfering with letter identification. Extreme disorientations, 120 degrees or more, exhibited no further impairment with increased disorientation, and all evidenced strong and similar length effects, suggesting letter-by-letter reading. The implications of the results for the reading of normal and transformed text are discussed.

Adolescent↗
PubMed1985

Lateralization effects in reading pointed and unpointed Hebrew.

Hebrew has two forms of spelling, pointed and unpointed. In the pointed spelling, diacritical signs (pointing) are added to consonantal letters to convey vowel information. These are omitted in the unpointed spelling. Since pointing conveys information that is critical for the prelexical derivation of phonology, it was hypothesized that its absence would prove detrimental for left hemisphere (LH) but not for right hemisphere (RH) reading and that, for the former, pointing effects would increase with increasing word length. Three experiments, one involving lexical decision and two involving word pronunciation, yielded little support for these hypotheses; rather, pointing had an overall adverse effect on performance, and this effect tended to be more pronounced for LH reading. In general, however, the results indicated an LH advantage. Since for central vision pointing has been found to aid performance under similar conditions, the results were seen to suggest a distinction between the visual and the phonological effects of pointing: pointing may impair early stages of visual analysis but may aid in the derivation of speech codes.

Female↗
PubMed1984

What is rotated in mental rotation?

Two hypotheses regarding mental rotation were contrasted. If subjects rotate each stimulus image to the upright (the image rotation hypothesis), then response time should depend solely on the extent of angular deviation from the upright. But if subjects rotate their frame of reference to match that of the disoriented stimulus (the frame rotation hypothesis), then response time should vary with the angular deviation between the current stimulus and the preceding stimulus. In four experiments, one involving normal and reflected letters (Experiment 1) and the other three involving lexical decisions on Hebrew letter strings (Experiments 2, 3A, and 3B), much stronger evidence for the image rotation hypothesis was found, though weak but systematic effects of frame rotation were also obtained. Increased likelihood that the same orientation would be repeated (Experiment 4) did not yield any stronger frame rotation effects. Also there was no indication of consistent individual differences in the preference for the frame rotation strategy (Experiment 3B). Additional findings pertinent to the application of the mental rotation paradigm to word recognition were discussed.

Female↗
PubMed1979

Figural symbolism in Chinese ideographs.

Hebrew-speaking subjects were presented with 42 pairs of Chinese characters designating antonymic concepts and were required to match them with their corresponding Hebrew words. Correct translation was significant and was related to foreign language study and academic experience. Highest success was found for the activity domain of the semantic differential and for attributes judged to afford a diagrammatic representation. Examination of the character-referent relationships suggested that translation success was due to principles of figural symbolism rather than to pictographic representation of the attributes in question. The results are seen as suggestive of the effects of figural symbolization on the invention and/or evolution of natural scripts and are discussed in terms of the manner in which the graphic medium has been fashioned to convey abstract concepts.

Adolescent↗
PubMed1976

Preference for color and form in preschoolers as related to color and form differentiation.

The preference for color or form as bases for similarity judgements among preschoolers (ages 2-5) and its relationship to the differentiation of form and color concepts as indexed by discrimination, identification, and labeling were investigated. As hypothesized, an early stage of form preference was found, replicating Brian and Goodenough's results. This was followed by the often-reported color preference and subsequent shift to form preference. A second hypothesis-that the relative salience of a dimension develops in parallel to its relative degree of differentiation-was not supported. This was so despite the fact that, within age groups, individuals who displayed higher proficiency in one dimension that in the other also preferred that dimension over the other. Implications for for existing explanations of developmental trends in preference were discussed.

Age Factors↗