Homophone effects in visual word recognition depend on homophone type and task demands.

This experiment examined how the characteristics of homophones and their mates influence homophone effects, as a function of task demands. Two types of homophones were presented: 1) low-frequency homophones with higher-frequency mates that are not animal names (e.g., maid--made), and 2) low-frequency homophones with mates that are, on average, of equivalent frequency and are animal names (e.g., foul--fowl). We observed a double dissociation: In the lexical decision task (LDT), there was a homophone effect for the first type of homophones but not for the second, whereas in the semantic categorization task (SCT) the opposite was true. These results suggest that in these tasks the effects of homophony arise when the homophone's mate creates competition in terms of the type of processing emphasized in the task, namely, orthographic processing in the LDT and semantic processing in the SCT.     

Effects of relative embodiment in lexical and semantic processing of verbs

Research examining semantic richness effects in visual word recognition has shown that multiple dimensions of meaning are activated in the process of word recognition (e.g., Yap et al., 2012). This research has, however, been limited to nouns. In the present research we extended the semantic richness approach to verb stimuli in order to investigate how verb meanings are represented. We characterized a dimension of relative embodiment for verbs, based on the bodily sense described by Borghi and Cimatti (2010), and collected ratings on that dimension for 687 English verbs. The relative embodiment ratings revealed that bodily experience was judged to be more important to the meanings of some verbs (e.g., dance, breathe) than to others (e.g., evaporate, expect). We then tested the effects of relative embodiment and imageability on verb processing in lexical decision (Experiment 1), action picture naming (Experiment 2), and syntactic classification (Experiment 3). In all three experiments results showed facilitatory effects of relative embodiment, but not imageability: latencies were faster for relatively more embodied verbs, even after several other lexical variables were controlled. The results suggest that relative embodiment is an important aspect of verb meaning, and that the semantic richness approach holds promise as a strategy for investigating other aspects of verb meaning.     

The benefits of sensorimotor knowledge: body-object interaction facilitates semantic processing

This article examined the effects of body–object interaction (BOI) on semantic processing. BOI measures perceptions of the ease with which a human body can physically interact with a word's referent. In Experiment 1, BOI effects were examined in 2 semantic categorization tasks (SCT) in which participants decided if words are easily imageable. Responses were faster and more accurate for high BOI words (e.g., mask ) than for low BOI words (e.g., ship ). In Experiment 2, BOI effects were examined in a semantic lexical decision task (SLDT), which taps both semantic feedback and semantic processing. The BOI effect was larger in the SLDT than in the SCT, suggesting that BOI facilitates both semantic feedback and semantic processing. The findings are consistent with the embodied cognition perspective (e.g., Barsalou's, 1999 , Perceptual Symbols Theory), which proposes that sensorimotor interactions with the environment are incorporated in semantic knowledge.     

Parkinson’s disease disrupts both automatic and controlled processing of action verbs

The problem of how word meaning is processed in the brain has been a topic of intense investigation in cognitive neuroscience. While considerable correlational evidence exists for the involvement of sensory-motor systems in conceptual processing, it is still unclear whether they play a causal role. We investigated this issue by comparing the performance of patients with Parkinson’s disease (PD) with that of age-matched controls when processing action and abstract verbs. To examine the effects of task demands, we used tasks in which semantic demands were either implicit (lexical decision and priming) or explicit (semantic similarity judgment). In both tasks, PD patients’ performance was selectively impaired for action verbs (relative to controls), indicating that the motor system plays a more central role in the processing of action verbs than in the processing of abstract verbs. These results argue for a causal role of sensory-motor systems in semantic processing.     

Predicting semantic priming at the item level

The current study explores a set of variables that have the potential to predict semantic priming effects for 300 prime–target associates at the item level. Young and older adults performed either lexical decision (LDT) or naming tasks. A multiple regression procedure was used to predict priming based upon prime characteristics, target characteristics, and prime–target semantic similarity. Results indicate that semantic priming (a) can be reliably predicted at an item level; (b) is equivalent in magnitude across standardized measures of priming in LDTs and naming tasks; (c) is greater following quickly recognized primes; (d) is greater in LDTs for targets that produce slow lexical decision latencies; (e) is greater for pairs high in forward associative strength across tasks and across stimulus onset asynchronies (SOAs); (f) is greater for pairs high in backward associative strength in both tasks, but only at a long SOA; and (g) does not vary as a function of estimates from latent semantic analysis (LSA). Based upon these results, it is suggested that researchers take extreme caution in comparing priming effects across different item sets. Moreover, the current findings lend support to spreading activation and feature overlap theories of priming, but do not support priming based upon contextual similarity as captured by LSA.     

Pretrial EEG coherence as a predictor of semantic priming effects

Twenty subjects were presented 240 randomized trials of a lexical decision task (LDT) while connected to a 16-electrode EEG montage. EEG data were acquired for 2 sec prior to the onset of each LDT trial. Alpha (9-13 Hz) coherence, alpha power, and 3- to 30-Hz power from five different combinations of EEG electrodes were used to predict semantic effects in the LDT trials. High pretrial coherence in the Right Hemisphere and Left Posterior-Parietal regions was associated with greater semantic facilitation (faster reaction times) in related-prime trials and greater semantic inhibition (slower reaction times) in unrelated-prime trials, relative to neutral-prime trials. No power variables were associated with semantic effects. Results support an information flow model of the functional significance of EEG coherence to cognitive processing.     

The functions of phonology in the acquisition of reading: Lexical and sentence processing

It has been claimed (V. Coltheart, Laxon, Rickard, & Elton, 1988) that learners as well as skilled readers use phonology for multiple functions in reading-for-meaning tasks. This claim was examined using lexical decision and sentence evaluation tasks. It was found in the first experiment that the type of instruction learners had received determined whether there was prelexical use of phonology in responding to items out of sentence context. Type of instruction had no effect when the items were in context. In the second experiment, performances on a homophone sentence evaluation task and a homophone semantic decision task, which excluded sentence processing, were examined. The results suggest that phonology served the function of access to lexical meanings in addition to any function in postlexical sentence processing. The obtained relationships between relative frequencies of the presented and unpresented homophone mates and item accuracy on these tasks were inconsistent with exclusive use of “direct access” but consistent with access of lexical meanings via phonology and application of a “spelling-check” procedure when multiple homophonic meanings are activated.     

Lexical decision task performance in blood-fearful and spider-fearful individuals

University undergraduates were pre-screened for blood fearfulness (fear of blood, n = 25), spider fearfulness (fear of spiders, n = 30), or non-fearfulness (n = 23) and presented with blood, spider, neutral, positive, and pseudoword (pronouncable nonword, like flirp) stimuli in a lexical decision task (LDT). Use of the LDT in phobic individuals may provide insight about how these individuals process, store, and ultimately use information and, in turn, how processing this information affects their day-to-day activities. Words were responded to faster than pseudowords. No group main or interaction effects emerged, and all groups responded faster and more accurately to spider words then blood words and neutral words. Results suggest that the single-word lexical decision task may not be sensitive in detecting lexical processing biases toward threat in these groups. Results also suggest that paradigms that are based on high-level, semantic-conceptual information processing (like lexical decision) are not sensitive enough to detect group differences in blood and spider phobias. Any array of perceptual and conceptual tasks taken together may be needed to detect these differences.     

Lexical decision task performance in blood-fearful and spider-fearful individuals

University undergraduates were pre-screened for blood fearfulness (fear of blood, n = 25), spider fearfulness (fear of spiders, n = 30), or non-fearfulness (n = 23) and presented with blood, spider, neutral, positive, and pseudoword (pronouncable nonword, like flirp) stimuli in a lexical decision task (LDT). Use of the LDT in phobic individuals may provide insight about how these individuals process, store, and ultimately use information and, in turn, how processing this information affects their day-to-day activities. Words were responded to faster than pseudowords. No group main or interaction effects emerged, and all groups responded faster and more accurately to spider words then blood words and neutral words. Results suggest that the single-word lexical decision task may not be sensitive in detecting lexical processing biases toward threat in these groups. Results also suggest that paradigms that are based on high-level, semantic-conceptual information processing (like lexical decision) are not sensitive enough to detect group differences in blood and spider phobias. Any array of perceptual and conceptual tasks taken together may be needed to detect these differences.     

There are many ways to be rich: Effects of three measures of semantic richness on visual word recognition

Previous studies have reported that semantic richness facilitates visual word recognition (see, e.g., Buchanan, Westbury, & Burgess, 2001; Pexman, Holyk, & Monfils, 2003). We compared three semantic richness measures--number of semantic neighbors (NSN), the number of words appearing in similar lexical contexts; number of features (NF), the number of features listed for a word's referent; and contextual dispersion (CD), the distribution of a word's occurrences across content areas-to determine their abilities to account for response time and error variance in lexical decision and semantic categorization tasks. NF and CD accounted for unique variance in both tasks, whereas NSN accounted for unique variance only in the lexical decision task. Moreover, each measure showed a different pattern of relative contribution across the tasks. Our results provide new clues about how words are represented and suggest that word recognition models need to accommodate each of these influences.     

Interplay of emotional valence and concreteness in word processing: An event-related potential study with verbs

The functional locus of emotional valence in word processing remains an open question. In event-related potentials, emotion has been found to elicit an early posterior negativity (EPN), which is assumed to reflect attention catching by the words’ meaning. Previously, the EPN was modulated by word category with verbs exhibiting longer EPN latencies compared with other word categories. Here we examined whether concreteness, a semantic variable, influences emotion processing. Within a lexical decision task for verbs, emotional valence (positive, negative, and neutral) was orthogonally combined with concreteness (concrete and abstract). EPN onset was found already at 250 ms post-stimulus for concrete verbs, whereas it started 50 ms later for abstract verbs. Concreteness effects occurred after the start of main effects of emotion. Thus, the elicitation of the EPN seems to be based on semantic processes, with emotional valence being accessed before other semantic aspects such as concreteness of verbs.     

Is more always better? Effects of semantic richness on lexical decision, speeded pronunciation, and semantic classification

Evidence from large-scale studies (Pexman, Hargreaves, Siakaluk, Bodner, & Pope, 2008) suggests that semantic richness, a multidimensional construct reflecting the extent of variability in the information associated with a word's meaning, facilitates visual word recognition. Specifically, recognition is better for words that (1) have more semantic neighbors, (2) possess referents with more features, and (3) are associated with more contexts. The present study extends Pexman et al. (2008) by examining how two additional measures of semantic richness, number of senses and number of associates (Pexman, Hargreaves, Edwards, Henry, & Goodyear, 2007), influence lexical decision, speeded pronunciation, and semantic classification performance, after controlling for an array of lexical and semantic variables. We found that number of features and contexts consistently facilitated word recognition but that the effects of semantic neighborhood density and number of associates were less robust. Words with more senses also elicited faster lexical decisions but less accurate semantic classifications. These findings point to how the effects of different semantic dimensions are selectively and adaptively modulated by task-specific demands.     

Semantic Ambiguity: Do Multiple Meanings Inhibit or Facilitate Word Recognition?

It is not clear whether multiple unrelated meanings inhibit or facilitate word recognition. Some studies have found a disadvantage for words having multiple meanings with respect to unambiguous words in lexical decision tasks (LDT), whereas several others have shown a facilitation for such words. In the present study, we argue that these inconsistent findings may be due to the approach employed to select ambiguous words across studies. To address this issue, we conducted three LDT experiments in which we varied the measure used to classify ambiguous and unambiguous words. The results suggest that multiple unrelated meanings facilitate word recognition. In addition, we observed that the approach employed to select ambiguous words may affect the pattern of experimental results. This evidence has relevant implications for theoretical accounts of ambiguous words processing and representation.     

Predicting semantic priming at the item level

The current study explores a set of variables that have the potential to predict semantic priming effects for 300 prime-target associates at the item level. Young and older adults performed either lexical decision (LDT) or naming tasks. A multiple regression procedure was used to predict priming based upon prime characteristics, target characteristics, and prime-target semantic similarity. Results indicate that semantic priming (a) can be reliably predicted at an item level; (b) is equivalent in magnitude across standardized measures of priming in LDTs and naming tasks; (c) is greater following quickly recognized primes; (d) is greater in LDTs for targets that produce slow lexical decision latencies; (e) is greater for pairs high in forward associative strength across tasks and across stimulus onset asynchronies (SOAs); (f) is greater for pairs high in backward associative strength in both tasks, but only at a long SOA; and (g) does not vary as a function of estimates from latent semantic analysis (LSA). Based upon these results, it is suggested that researchers take extreme caution in comparing priming effects across different item sets. Moreover, the current findings lend support to spreading activation and feature overlap theories of priming, but do not support priming based upon contextual similarity as captured by LSA.     

Interactions of reading and semantics along the ventral visual processing stream

Converging evidence supports a distributed-plus-hub view of semantic processing, in which there are distributed modular semantic sub-systems (e.g., for shape, colour, and action) connected to an amodal semantic hub. Furthermore, object semantic processing of colour and shape, and lexical reading and identification, are processed mainly along the ventral stream, while action semantic processing occurs mainly along the dorsal stream. In Experiment 1, participants read a prime word that required imagining either the object or action referent, and then named a lexical word target. In Experiments 2 and 3, participants performed a lexical decision task (LDT) with the same targets as in Experiment 1, in the presence of foils that were legal nonwords (NW; Experiment 2) or pseudohomophones (PH; Experiment 3). Semantic priming was similar in effect size regardless of prime type for naming, but was greater for object primes than action primes for the LDT with PH foils, suggesting a shared-stream advantage when the task demands focus on orthographic lexical processing. These experiments extend the distributed-plus-hub model, and provide a novel paradigm for further research.     

Effects of modality on subjective frequency estimates and processing of spoken and printed words

Previous research (Garber & Pisoni, 1991; Pisoni & Garber, 1990) has demonstrated that subjective familiarity judgments for words are not differentially affected by the modality (visual or auditory) in which the words are presented, suggesting that participants base their judgments on fairly abstract, modality-independent representations in memory. However, in a recent large-scale study in Japanese (Amano, Kondo, & Kakehi, 1995), marked modality effects on familiarity ratings were observed. The present research further examined possible modality differences in subjective ratings and their implications for word recognition. Specially selected words were presented to participants for frequency judgments. In particular, participants were asked how frequently they read, wrote, heard, or said a given spoken or printed word. These ratings were then regressed against processing times in auditory and visual lexical decision and naming tasks. Our results suggest modality dependence for some lexical representations.     

Cognitive processing and motor execution in the lexical decision task: a developmental study

We investigated lexical decision making in children and adults by analyzing spatiotemporal characteristics of responses involving a hand movement. Children’s and adults’ movement trajectories were assessed in three tasks: a lexical decision task (LDT), a pointing task that involved minimal cognitive processing, and a symbol task requiring a simple binary decision. Cognitive interference on motor performance was quantified by analyzing movement characteristics in the LDT and symbol task relative to the pointing task. Across age groups, movements in the LDT were less smooth, slower, and more strongly curved to the opposite response option, and these interference effects decreased steadily with age. Older children showed stronger interference effects than did adults, even though their reaction times were similar to adults’ performance. No comparable effects were found in the symbol task, indicating that task characteristics such as response mapping and decision selection alone are not able to explain the developmental differences observed in the LDT. Our results indicate substantial overlap between cognitive processing and motor execution in the LDT in children that is not captured by computational models of visual word recognition and cognitive development.     

The priming effect of translation equivalents across languages for concrete and abstract words

The present study used a masked priming paradigm and two language tasks (lexical decision, semantic categorical judgment) to investigate whether concrete and abstract words share the same degree of conceptual representation across languages for bilinguals. The results showed that the priming effect of translation equivalents did not differ for concrete and abstract words in the lexical decision task, in both prime-target directions (in Experiment 1). The same results were also found in the semantic categorical judgment task in either prime-target direction (in Experiment 2). Our results do not provide support for the representation difference hypothesis of concrete and abstract words of Distributed Representation Model (De Groot, 1992a, 1992b; Van Hell & De Groot, 1998), which assumes that concrete words share more semantic components in the conceptual representations across languages, compared with abstract words. Rather, our findings suggest that both concrete and abstract words have the same degree of overlap in conceptual representations across a bilingual's two languages.