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PubMed2005

Semantic feature production norms for a large set of living and nonliving things.

Semantic features have provided insight into numerous behavioral phenomena concerning concepts, categorization, and semantic memory in adults, children, and neuropsychological populations. Numerous theories and models in these areas are based on representations and computations involving semantic features. Consequently, empirically derived semantic feature production norms have played, and continue to play, a highly useful role in these domains. This article describes a set of feature norms collected from approximately 725 participants for 541 living (dog) and nonliving (chair) basic-level concepts, the largest such set of norms developed to date. This article describes the norms and numerous statistics associated with them. Our aim is to make these norms available to facilitate other research, while obviating the need to repeat the labor-intensive methods involved in collecting and analyzing such norms. The full set of norms may be downloaded from www.psychonomic.org/archive.

Adult↗

PubMed2006

Exploring the role of attention during memory retrieval: effects of semantic encoding and divided attention.

Research on attention and memory suggests that semantic encoding leads to retrieval that is highly susceptible to divided attention. Three experiments tested this proposition and showed that dividing attention did not selectively affect semantically encoded items. Participants encoded a list of words in one of two ways: semantically or phonetically. Later, memory was assessed using either a standard recognition test (Experiment 1) or a rhyme recognition test (Experiments 2 and 3). The participants took the memory test either alone (full attention) or while simultaneously performing a secondary task (divided attention). Recognition accuracy was reduced by divided attention on both recognition tests, and semantically and phonetically encoded words were equally affected.

Attention↗

PubMed2003

Semantic processing of Arabic, Kanji, and Kana numbers: evidence from interference in physical and numerical size judgments.

Two experiments were conducted with the following objectives (1) to replicate the finding of similar semantic representation of Arabic and written-word (Kanji and Kana) numbers with a direct numerical task, (2) to investigate the automatic semantic processing of Arabic and written-word numbers, and (3) to verify whether the assumption of a common semantic representation is valid in an indirect numerical task. Subjects were asked to judge which of two numbers (e.g, 6-8) was larger either in its numerical size (Experiment 1) or in its physical size (Experiment 2) using the three notations. Effects of two factors were analyzed: the congruity between numerical and physical size and the numerical distance. The effects of these factors were very similar across the three notations in Experiment 1, but were drastically different in Experiment 2. The results of Experiment 2 demonstrated the nonsemantic processing of Kana numbers, and suggest that there may be separate semantic representations for Arabic and Kanji numbers.

Adult↗

PubMed2003

Use of latent semantic analysis for predicting psychological phenomena: two issues and proposed solutions.

Latent semantic analysis (LSA) is a computational model of human knowledge representation that approximates semantic relatedness judgments. Two issues are discussed that researchers must attend to when evaluating the utility of LSA for predicting psychological phenomena. First, the role of semantic relatedness in the psychological process of interest must be understood. LSA indices of similarity should then be derived from this theoretical understanding. Second, the knowledge base (semantic space) from which similarity indices are generated must contain 'knowledge' that is appropriate to the task at hand. Proposed solutions are illustrated with data from an experiment in which LSA-based indices were generated from theoretical analysis of the processes involved in understanding two conflicting accounts of a historical event. These indices predict the complexity of subsequent student reasoning about the event, as well as hand-coded predictions generated from think-aloud protocols collected when students were reading the accounts of the event.

Adolescent↗

PubMed2004

Can semantic relatedness explain the enhancement of memory for emotional words?

Memory for emotional items is often better than memory for neutral items. In three experiments, we examined whether this typical finding is due to the higher semantic relatedness inherent to emotional items, a confound in previous studies. We also controlled for other possible confounding variables, such as imagery. In Experiments 1 and 2, participants encoded lists of emotional and categorized neutral words equivalent in semantic relatedness, as well as lists of random neutral words with lower semantic relatedness. In Experiment 3, the lists were mixed, containing words from all the conditions. Surprise free recall was tested after a 40- to 55-min retention interval. Free recall of emotional words was better than that of random neutral words, replicating the classic effect. Importantly, categorized words were recalled better than random neutral words, and not worse than emotional words. These results emphasize the important role of semantic relatedness in the classic effect and suggest that organizational processes operate alongside arousal-related ones to enhance memory for emotional material.

Adult↗

PubMed2001

Semantic processing in visual word recognition: activation blocking and domain specificity.

Lexical decision to a target is typically facilitated when a related prime is simply read, but is typically eliminated if subjects carry out a letter search on the prime when probe and prime appear simultaneously. Three experiments involving the addition of a task-irrelevant word to this prime search paradigm address (1) Stolz and Besner's (1996, 1998) account in which semantic priming is eliminated because letter search on the prime instantiates an activation block between lexical and semantic levels of representation, (2) Chiappe, Smith, and Besner's (1996) account that activation blocking is domain specific, and (3) Neely and Kahan's (2001) claim that semantic activation is context independent and capacity free. The results are (1) consistent with the account that activation blocking is general to a level, rather than item specific, (2) consistent with the account that activation blocking is domain specific, and (3) inconsistent with the claim that semantic activation is context independent and capacity free.

Association↗

PubMed2001

Susceptibility to semantic illusions: an individual-differences perspective.

When asked How many animals of each kind did Moses take on the ark?, people frequently respond "two" even though they know it was Noah, not Moses, who took animals on the ark. We replicate previous research by showing that susceptibility to semantic illusions is influenced by the semantic relatedness of both the impostor word and the surrounding context. However, we also show that the two text manipulations make independent contributions to semantic illusions, and we propose two individual-differences mechanisms that might underlie these two effects. We propose that the ability to resist the lure of a semantically related impostor word is related to the individual's skill at accessing and reasoning about knowledge from long-term memory. And we propose that the ability to resist the lure of the surrounding sentential context is related to the individual's capacity to simultaneously process and store information in working memory.

Adult↗

PubMed2004

Single letter coloring and spatial cuing eliminates a semantic contribution to the Stroop effect.

Previous work has shown that the Stroop effect is reduced in size when a single letter is colored and spatially precued. The present experiment addresses a number of criticisms of this work by (1) providing a direct measure of semantic processing, (2) using a vocal response instead of a manual one, and (3) using a more appropriate baseline. A semantically based Stroop effect (slower color naming for color-associated words than for color-neutral words) is observed when all letters in the display are precued and appear in a homogeneous color. This Stroop effect is statistically eliminated when a single letter is precued and is the "odd man out" in terms of its color. Two explanations are considered. In one, single-letter coloring and cuing serve to curtail semantic processing. In the other, single-letter coloring and cuing help to keep the informational sources (i.e, color, word) separate and hence reduce interference, but semantic analysis is not curtailed. The latter account provides a more complete account of existing data.

Color Perception↗

PubMed1993

A case study of anomaly detection: shallow semantic processing and cohesion establishment.

Although the establishment of a coherent mental representation depends on semantic analysis, such analysis is not necessarily complete. This is illustrated by failures to notice the anomaly in questions such as, "When an airplane crashes, where should the survivors be buried?" Four experiments were carried out to extend knowledge of what determines the incidental detection of the critical item. Detection is a function of the goodness of global fit of the item (Experiments 1 and 2) and the extent to which the scenario predicts the item (Experiment 3). Global good fit appears to result in shallow processing of details. In Experiment 4, it is shown that if satisfactory coherence can be established without detailed semantic analysis, through the recruitment of suitable information from a sentence, then processing is indeed shallow. The studies also show that a text is not understood by first producing a local semantic representation and then incorporating this into a global model, and that semantic processing is not strictly incremental.

Adult↗

PubMed1998

The influence of semantic fit on on-line sentence processing.

The interactive influence of verb complement preferences and noun phrase semantic fit on resolution of temporary syntactic ambiguity was investigated in an eye movement experiment. The present semantic fit manipulation included noun phrases that fit well as direct objects of the verbs that they followed and noun phrases that were possible but less likely direct objects of the verbs in question. This contrasted with existing research on the use of verb complement preferences and semantic fit during sentence processing, in which processing of noun phrases that are possible direct objects has been compared with processing of noun phrases that are not possible direct objects of the verbs that they follow. Verb complement preference information and noun phrase semantic fit interacted at early stages of on-line sentence processing. Implications of these results for interactive and structural models of sentence processing are discussed.

Adult↗

PubMed2000

Morphological priming: dissociation of phonological, semantic, and morphological factors.

Previous experiments based on a masked-priming paradigm revealed robust morphological priming effects induced by two derivational morphemes in Hebrew: the root and the verbal pattern. However, considering the special characteristics of the masked-priming paradigm, the possible contributions of phonological and/or semantic factors to these morphological effects could not be firmly assessed. In the present study, the role of these factors in morphological priming was examined, using cross-modal presentation. Experiment 1 revealed that priming between morphologically related words in Hebrew is determined by higher level linguistic characteristics and cannot be reduced to phonological overlap. Experiment 2 confirmed that morphological priming occurs in Hebrew even when primes and targets are not semantically related but, nevertheless, increases with semantic similarity. The results support the claim that morphological priming cannot be accounted for by considering semantic and phonological factors alone, and they exemplify the potential of using both masked and cross-modal priming to examine morphological processing.

Adult↗

PubMed2000

Semantic priming without association: a meta-analytic review.

A meta-analysis of 26 studies indicated that automatic semantic priming can occur without association. Priming did not vary substantially with differences in variables that affect automatic versus strategic processing, such as time spent processing the prime and target, relationship proportion, and task (except that average effects were smaller in the naming task). Although category coordinates were investigated in the majority of studies, synonyms, antonyms, and script relations also demonstrated priming; functional relations showed greater priming, and essential and perceptual relations showed less. The average effect size for semantic priming was smaller than that for associative priming, suggesting that there is an "associative boost" from adding an associative relationship to a semantic one. The implications of these findings for the modularity thesis and for models of semantic priming are discussed.

Adult↗

PubMed2001

Focal retrograde amnesia and the episodic-semantic distinction.

This article reports a review of focal retrograde amnesia (FRA), or the phenomenon of organically based severe memory loss restricted to retrograde, or pretraumatic, memory. Cases of FRA are classified according to the type of memory loss: episodic, semantic, or both. A few different clusters of the disorder were identified. Lesions to either the anterior temporal lobes or the posterior/visual cortex can result in an FRA that devastates retrograde episodic memory, while having smaller effects on semantic memory. A number of left-hemisphere patients have FRA confined to semantic memory. There are several additional examples of FRA following minor cerebral trauma that disrupts either episodic memory alone or both episodic and semantic memory that are not accompanied by evidence of structural brain lesions. We discuss these different profiles of FRA and their implications for the understanding of memory retrieval.

Amnesia, Retrograde↗

PubMed2004

Dissociating semantic and phonological maintenance using fMRI.

Functional magnetic resonance imaging (fMRI) distinguished regions of neural activity associated with active maintenance of semantic and phonological information. Subjects saw a single word for 2 sec, and following a 10-sec delay, made a judgment about that word. In the semantic task, subjects focused on the meaning of the word and decided whether a second word was synonymous with it. In the phonological task, subjects repeated the word silently and decided whether it shared a vowel sound with a nonsense word. Analyses allowed for isolation of neural activity during the maintenance delay. Semantic maintenance elicited greater activity in bilateral inferior frontal gyrus and left middle temporal gyrus regions of interest (ROI). In contrast, there was greater activity for phonological maintenance in the left superior parietal ROI. These results show a frontal-temporal network involved in actively maintaining the meanings of words, and they indicate that semantic and phonological maintenance processes are dissociable within working memory.

Adult↗

PubMed2000

[Semantic processing of words in selective listening: an examination using recognition tests and event-related brain potentials].

Two experiments were conducted to investigate the degree of semantic processing for unattended words. In a dichotic listening task, each participant was required to attend selectively to either a word sequence in one ear or a speech passage in the opposite ear. The selective listening was confirmed by attenuated P1-N1 and N400 waves of the event-related brain potential to unattended words. The N400 attenuation with semantic priming was observed only for attended words. In a following recognition test with a booklet and auditory presentation, the percentage of false alarms for "new" words (or lures) semantically related to "old" words was higher when the "old" words were attended in selective listening than when unattended. These findings suggest that selective attention can act before and/or at a level of semantic processing.

Adult↗

PubMed2001

[The relationship between the categorical perception of facial expressions and semantic distances].

It has been argued whether the facial expression is recognized categorically or dimensionally. We investigated this issue using three sets of morphed photographic facial images (happiness to anger, surprise, and sadness). Our interest is whether the experimental data of categorical perception can be explained by the dimensional point of view. Experiment 1 examined the facial stimuli generated by FACS. In Experiment 2, subjects were asked to discriminate some pairs of faces and to categorize the emotion shown one at a time. The discrimination accuracy between categories was better than that within each category. In Experiment 3, subjects were asked to rate those stimuli following the semantic differential technique. Then we examined the relationship between the discrimination accuracy obtained in Experiment 2 and the semantic distances obtained in Experiment 3, defined by Euclidean distances between pairs of stimuli in the factor space that was constituted two factors interpreted as "pleasantness" and "activities". Discrimination accuracy within each category increased as a function of the semantic distances, whereas discrimination accuracy between categories remained high irrespective of the different semantic distances.

Adolescent↗

PubMed2003

[The effect of semantic satiation on a double lexical decision task].

It is known that a semantic satiation effect depends upon the characteristics of the task. For example, the effect has been found on a category decision task, but not found on a lexical decision task. Based on these results, previous studies concluded that because the task is influenced from factors other than semantic access, the lexical decision task was inadequate for semantic satiation. On the contrary, this study found the effect on a variation of a lexical decision task. In Experiment 1, 16 college students performed a category-matching judgement. In Experiment II, 24 students performed a lexical decision on a pair of letter strings. The results of both experiments showed the semantic satiation. These results suggested that a lexical decision task was able to detect the satiation as long as the task was complicated.

Adult↗

PubMed1999

Model-based semantic dictionaries for medical language understanding.

Semantic dictionaries are emerging as a major cornerstone towards achieving sound natural language understanding. Indeed, they constitute the main bridge between words and conceptual entities that reflect their meanings. Nowadays, more and more wide-coverage lexical dictionaries are electronically available in the public domain. However, associating a semantic content with lexical entries is not a straightforward task as it is subordinate to the existence of a fine-grained concept model of the treated domain. This paper presents the benefits and pitfalls in building and maintaining multilingual dictionaries, the semantics of which is directly established on an existing concept model. Concrete cases, handled through the GALEN-IN-USE project, illustrate the use of such semantic dictionaries for the analysis and generation of multilingual surgical procedures.

Dictionaries, Medical as Topic↗