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PubMed2005

Effects of semantic cues on mathematical modeling: evidence from word-problem solving and equation construction tasks.

Mathematical solutions to textbook word problems are correlated with semantic relations between the objects described in the problem texts. In particular, division problems usually involve functionally related objects (e.g., tulips-vases) and rarely involve categorically related objects (e.g., tulips-daisies). We examined whether middle school, high school, and college students use object relations when they solve division word problems (WP) or perform the less familiar task of representing verbal statements with algebraic equations (EQ). Both tasks involved multiplicative comparison statements with either categorically or functionally related objects (e.g., "four times as many cupcakes [commuters] as brownies [automobiles]"). Object relations affected the frequency of correct solutions in the WP task but not in the EQ task. In the latter task, object relations did affect the structure of nonalgebraic equation errors. We argue that students use object relations as "semantic cues" when they engage in the sense-making activity of mathematical modeling.

Adolescent↗

PubMed2005

Age of acquisition effects in the semantic processing of pictures.

In two experiments, we investigated the role of age of acquisition (AoA) in the categorizing of objects in semantic tasks that do not require access to the object names. In both a found inside or outside the house (Experiment 1A) and a smaller or larger than a loaf of bread (Experiment 2A) classification task, objects with earlier-acquired names were categorized more quickly than those with later-acquired names. Experiments 1B and 2B also showed AoA effects on object-naming times for the same pictures. We conclude that AoA operates within the identification process in a fashion not simply restricted to name retrieval. These effects may be better explained in terms of the connectionist model proposed by Ellis and Lambon Ralph (2000) or by accounts that locate AoA within the semantic system (e.g., Brysbaert, Van Wijnendaele, & De Deyne, 2000; van Loon-Vervoorn, 1989).

Adolescent↗

PubMed2005

Semantic competition between hierarchically related words during speech planning.

There is overwhelming evidence that during speech planning semantically related words become lexically activated and compete for selection with the to-be-produced target word. The vast majority of this evidence stems from studies using the picture-word task, in which a distractor word (e.g., bird) drawn from the same semantic category as the target (e.g., fish) was shown to inhibit the picture-naming response more strongly than did an unrelated distractor word. By contrast, corresponding evidence from distractor words (e.g., carp) bearing a hierarchical relation to the target (e.g., fish) is sparse and inconclusive. In the present study, we investigated effects of subordinate-level distractors during basic-level naming and effects of basic-level distractors during subordinate-level naming. Hierarchically related distractors were found to inhibit the naming response in both situations. This pattern of results did not depend on whether the pictures were preferably named at the basic level or at the subordinate level. The results suggest that hierarchically related name alternatives compete for selection.

Humans↗

PubMed2003

Long-term semantic transfer: an overlapping-operations account.

Semantic priming is usually a short-lived effect. However, it is also usually investigated using undemanding tasks, such as naming or lexical decision. We instead required subjects to perform category verification. We observed semantically mediated transfer occurring at an average lag of 90 intervening trials. We also observed that this priming was specific to the stimulus properties made salient in prime and probe displays and the particular task demanded in those displays. We interpret the results within an overlapping-operations framework, based on the work of Kolers (e.g., 1976).

Humans↗

PubMed2003

Semantic activation in the absence of perceptual awareness.

Participants performed a semantic categorization task on a target that was preceded by a prime word belonging either to the same category (20% of trials) or to a different category (80% of trials). The prime was presented for 33 msec and followed either immediately or after a delay by a pattern mask. With the immediate mask, reaction times (RTs) were shorter on related than on unrelated trials. This facilitatory priming reached significance at prime-target stimulus onset asynchronies (SOAs) of 400 msec or less and remained unaffected by task practice. With the delayed mask, RTs were longer on related than on unrelated trials. This reversed (strategic) semantic priming proved to be significant (1) only at a prime-target SOA of 400 msec or longer and (2) after the participants had some practice with the task. The present findings provide further evidence that perceiving a stimulus with and without phenomenological awareness can lead to qualitatively different behavioral consequences.

Awareness↗

PubMed2004

Serial processing in melody identification and the organization of musical semantic memory.

Unlike the visual stimuli used in most object identification experiments, melodies are organized temporally rather than spatially. Therefore, they may be particularly sensitive to manipulations of the order in which information is revealed. Two experiments examined whether the initial elements of a melody are differentially important for identification. Initial exposures to impoverished versions of a melody significantly decreased subsequent identification, especially when the early exposures did not include the initial notes of the melody. Analyses of the initial notes indicated that they are differentially important for melody identification because they help the listener detect the overall structure of the melody. Confusion errors tended to be songs that either were drawn from the same genre or shared similar phrasing. These data indicate that conceptual processing influences melody identification, that phrase-level information is used to organize melodies in semantic memory, and that phrase-level information is required to effectively search semantic memory.

Auditory Perception↗

PubMed2001

Perceptual and semantic sources of category-specific effects: event-related potentials during picture and word categorization.

In two experiments the effect of object category on event-related potentials (ERPs) was assessed while subjects performed superordinate categorizations with pictures and words referring to objects from natural (e.g., animal) and artifactual (e.g., tool) categories. First, a category probe was shown that was presented as name in Experiment 1 and as picture in Experiment 2. Thereafter, the target stimulus was displayed. In both experiments, analyses of the ERPs to the targets revealed effects of category at about 160 msec after target onset in the pictorial modality, which can be attributed to category-specific differences in perceptual processing. Later, between about 300-500 msec, natural and artifactual categories elicited similar ERP effects across target and category modalities. These findings suggest that perceptual as well as semantic sources contribute to category-specific effects. They support the view that semantic knowledge associated with different categories is represented in multiple subsystems that are similarly accessed by pictures and words.

Adult↗

PubMed2002

Subliminal words activate semantic categories (not automated motor responses).

Semantic priming by visually masked, unidentifiable ("subliminal") words occurs robustly when the words appearing as masked primes have been classified earlier in practice as visible targets. It has been argued (Damian, 2001) that practice enables robust subliminal priming by automatizing learned associations between words and the specific motor responses used to classify them. Two experiments demonstrate that, instead, the associations formed in practice that underlie subliminal priming are between words and semantic categories. Visible words classified as pleasant or unpleasant in practice with one set of response key assignments functioned later as subliminal primes with appropriate valence, even when associations of keys with valences were reversed before the test. This result shows that subliminal priming involves unconscious categorization of the prime, rather than just the automatic activation of a practiced stimulus-response mapping.

Automatism↗

PubMed2002

Serial position effects in semantic memory: reconstructing the order of verses of hymns.

Serial position effects (primacy and recency) have been consistently demonstrated in both short- and long-term episodic memory tasks. The search for corresponding effects in semantic memory tasks (e.g., reconstructing the order of U.S. presidents) has been confounded by factors such as differential exposure to stimuli. In the present study, the stimuli were six-verse hymns that would have been sung from the first to the last verse by churchgoers on numerous occasions. Participants were presented with the verses of each hymn in random order and were required to reconstruct the correct order. Primacy and recency effects were significantly more evident for churchgoers than for nonchurchgoers. Moreover, error gradients were steeper than chance for churchgoers but not for nonchurchgoers; in other words, churchgoers' errors were more likely to be close to the correct position than further away. These findings provide the first unequivocal demonstration of serial position effects in semantic memory.

Adolescent↗

PubMed2001

When SOFA primes TOUCH: interdependence of spelling, sound, and meaning in "semantically mediated" phonological priming.

Three experiments test for semantically mediated priming of a word's phonology (e.g., sofa, an associate of couch, primes naming performance to touch). In the first two experiments, words that were body-rime-inconsistent (compare touch to couch) were used as naming targets. In the third experiment, words that were body-rime-consistent were also used (i.e., sofa primed pouch). Low-frequency inconsistent words yield a high rate of pronunciation errors when they were primed by indirectly related words, such as sofa, in both a standard naming task and a speeded naming task. High-frequency inconsistent words yielded slower naming times when they were primed by indirectly related words in a speeded naming task, but consistent words showed no significant effects of the primes. The results suggest that the relationship between semantics and phonology plays an important, early role in word perception.

Adult↗

PubMed2005

Priming of semantic classifications: late and response related, or earlier and more central?

Priming of semantic classifications may occur because of response-related priming or because of priming at a more central locus. To separate these two possibilities, we randomly intermixed adjectives and first names, using a response window procedure. Participants decided whether the adjectives were positively or negatively valenced and whether the names were male or female. Each of these kinds of targets was preceded by adjective or name primes associated with responses that either matched or mismatched the correct response to the target. Results showed that priming of semantic classification involves two components: a major response-related one, modulated by prime visibility and prime-target repetition, and a smaller component with a more central locus that is less susceptible to context effects.

Female↗

PubMed2004

Episodic and semantic components of the compound-stimulus strategy in the explicit task-cuing procedure.

The explicit task-cuing procedure is commonly used to study executive control processes involved in set switching, but performance in this task-switching procedure may be accomplished without switching tasks. Subjects may perform both tasks by using a compound-stimulus strategy, in which subjects encode the cue, encode the target, and use the combination as a compound retrieval cue to choose the appropriate response. We manipulated the number of targets (8, 16,32, or 640) that subjects experienced in a four-cue/two-task procedure to separate episodic and semantic memory retrieval components of the compound-stimulus strategy. Cue repetitions were faster than task repetitions, and task repetitions were only slightly faster than task alternations, suggesting that cue repetition effects account for the bulk of the difference between repetitions and alternations. We found the same effects with all target set sizes. The results are consistent with use of a semantic compound-stimulus strategy.

Cues↗

PubMed1989

Automatic and directed search processes in solving simple semantic-memory problems.

The cognitive processes involved in simple semantic-memory problems were investigated in four experiments. On each trial of Experiments 1 and 2, two stimulus words were presented, with the instructions to find a third word (i.e., the solution) that, when coupled with each of the stimuli, would yield two word pairs used in everyday language (e.g., surprise and birthday, for which the solution is party). The results of the two experiments indicated that informing the subject whether the solution constituted the first or the second element in the word pairs facilitated both likelihood and speed of solution attainment. In addition, solution attainment was relatively high for items based on frequently used word pairs (Experiment 1) and for items in which the stimuli appear, in everyday language, in a small number of word pairs (Experiment 2). In Experiment 3, the subjects were required to produce word pairs containing one of the two stimulus words from the items used in Experiment 2. Solution production was facilitated by rehearsing the second stimulus word of the specific item. The conclusion, supported by a post hoc analysis of the results of Experiments 2 and 3 (Experiment 4), was that indirect priming from one stimulus word may facilitate solution production from a searched word. These results are interpreted in terms of automatic and controlled processes, and their relevance to two different models for retrieval from semantic memory is discussed.

Adolescent↗

PubMed1990

Detectionless processing with semantic activation? A footnote to Greenwald, Klinger, and Liu (1989)

Recently published research has suggested that, in a pattern masking task, semantic activation caused by the target may continue to exist even though subjects cannot detect the target. The experiments are reassessed as an exceptional case of the more general rule that subjects are able to use residual semantic activation to actually detect targets. Furthermore, residual graphic information is far less effective at supporting near-chance target detections.

Arousal↗

PubMed1989

Focused search of semantic cases: the effects of question form and case status.

The present study was designed to identify and examine some of the variables that influence the focused search of semantic cases in question answering. Singer, Parbery, and Jakobson (1988) have previously reported that people can focus on the case interrogated by a question and can largely disregard irrelevant cases. In the present study, people learned facts, such as the pilot painted the garage with the roller, the spraygun, and the brush. One day later, they answered questions that focused on a particular case. For example, the question did the pilot paint with a spraygun? focuses on the instrument case. Experiment 1 revealed that people can focus on a particular case in response both to complete questions and to comparable word probes, such as "pilot spraygun." Therefore, the given-new structure of questions is not essential to focused search. Experiment 2 revealed that people have a difficult time ignoring the agent case, even when it is irrelevant to the question. This corroborates proposals that agent and action information are closely interrelated in the representation of a fact. These results help to delineate the phenomenon of the focused search of semantic cases.

Cues↗

PubMed1996

Accessing short-term memory with semantic and phonological information: a time-course analysis.

The time course for accessing short-term memory representations on the basis of item, phonological, and semantic information was measured with a speed-accuracy tradeoff (SAT) variant of a recognition probe task. Subjects studied 5-word lists and then judged whether a test word (1) was in the study list (item judgment); (2) rhymed with a word in the study list (rhyme judgment); or (3) was a synonym of a word in the study list (synonym judgment). Analysis of the SAT retrieval functions demonstrated that judgments based on phonological and semantic information were slower and less accurate than judgments based on composite item representations. The slower retrieval dynamics for rhyme and synonym judgments suggest that judgments based on component properties of the memory trace are mediated by either a generate or recall process distinct from the parallel or direct-access mechanism used in item judgments.

Adult↗

PubMed1996

Perceptual and conceptual priming in a semantic reprocessing task.

Two experiments are reported that addressed the relative involvement and nature of perceptual and conceptual priming in a semantically complex task. Both experiments investigated facilitation from repeated semantic comparison trials in which subjects decided whether two words had the same meaning (e.g., moist damp). The first experiment compared the magnitude and persistence of perceptual and conceptual priming components. Perceptual priming effects were modest, and contrary to some previous evidence, they did not appear to be more persistent than nonperceptual priming effects. The second experiment investigated the memory processes involved when perceptual priming was eliminated through a modality change between prime and target trials. Evidence suggested that conceptual priming primarily involved memory for the meaning comparison processes rather than better access to existing memory for the stimulus words.

Adolescent↗

PubMed1999

The importance of semantic similarity to the irrelevant speech effect.

Irrelevant speech disrupts immediate recall of a short sequence of items. Salamé and Baddeley (1982) found a very small and nonsignificant increase in the irrelevant speech effect when the speech comprised items semantically identical to the to-be-remembered items, leading subsequent researchers to conclude that semantic similarity plays no role in the irrelevant speech effect. Experiment 1 showed that strong free associates of the to-be-remembered items disrupted serial recall to a greater extent than words that were dissimilar to the to-be-remembered items. Experiment 2 showed that this same pattern of disruption in a free recall task. Theoretical implications of these findings are discussed.

Adult↗