Semantic asymmetries are modulated by phonological asymmetries: Evidence from the disambiguation of homophonic versus heterophonic homographs

The present study investigated cerebral asymmetries in accessing multiple meanings of two types of homographs: homophonic homographs (e.g., bank) and heterophonic homographs (e.g., tear). Participants read homographs preceded by either a biasing or a non-biasing sentential context and performed a lexical decision on lateralized targets presented 150 ms after onset of the sentence-final ambiguous prime. Targets were either related to the dominant or the subordinate meaning of the preceding homograph or were unrelated to it. In the case of homophonic homographs – our results converge with previous findings: both activation and selection processes are faster in the LH than in the RH. Importantly, however, in the case of heterophonic homographs – opposite asymmetries were found. These results suggest that semantic asymmetries are modulated by phonology. They are discussed in the context of a model of functional architecture of reading in the two hemispheres in which orthography, phonology and semantics are fully interconnected in the LH, whereas in the RH, orthography and phonology are not directly connected, such that phonological processes are mediated by semantics.     

Developmental changes in neural activity to familiar words and gestures

Infants younger than 20 months of age interpret both words and symbolic gestures as object names. Later in development words and gestures take on divergent communicative functions. Here, we examined patterns of brain activity to words and gestures in typically developing infants at 18 and 26 months of age. Event-related potentials (ERPs) were recorded during a match/mismatch task. At 18 months, an N400 mismatch effect was observed for pictures preceded by both words and gestures. At 26 months the N400 effect was limited to words. The results provide the first neurobiological evidence showing developmental changes in semantic processing of gestures.     

Factors in the waning of muricide in the rat: I. Analysis of intra- and intersession decrement

If each mouse killed by a rat is removed from the rat's home cage and replaced immediately by another live mouse, the rate of killing declines within 1- and 3-hr sessions. Muricide could not then be dishabituated by either a “nonspecific” stimulus (a loud noise) or a specific change in target characteristics (a frog substituted for the mouse). By systematically varying intersession intervals, we found that 1 hr of ad lib killing produced a monotonically decreasing suppression of muricide over the succeeding 96 hr. Subjects performed an interesting kind of forward didng which was influenced by both dishabituating stimuli and killing; this may be a form of die placement behavior.     

Event structure as a basis of semantic processing of familiar metaphors

In this paper I propose a model of metaphor interpretation that would account for the possibility that semantic processing of familiar metaphors no longer go through the sequential steps of alignment and projection, but may rather be established upon schematic semantic units allowing faster processing. The proposition is grounded on the notion that metaphors are formed based on peoples’ perception of what is typically associated with entities. It is suggested that in its most abstract form, these associations are essentially events, analyzed in terms of event structure.     

NONCONTINGENT PRESENTATION OF ATTENTION AND ALTERNATIVE STIMULI IN THE TREATMENT OF ATTENTION-MAINTAINED DESTRUCTIVE BEHAVIOR

Previous research has demonstrated that destructive behavior may be reduced through noncontingent presentation of attention when attention is identified as the stimulus responsible for behavioral maintenance. Because it may not always be possible to deliver attention in all situations, we examined the extent to which alternative stimuli that have been identified through a choice assessment would substitute for attention (the functional analysis—based reinforcer) in a noncontingent reinforcement procedure. Prior to treatment, functional analyses demonstrated that the destructive behavior of 2 clients with mental retardation was maintained by adult attention. Next, a stimulus choice assessment identified highly preferred tangible items for the 2 clients. Finally, we compared the effectiveness of two noncontingent reinforcement procedures: continuous noncontingent access to attention and continuous noncontingent access to the tangible item identified in the choice assessment. For both clients, these noncontingent reinforcement procedures reduced destructive behavior. The results are discussed in terms of the clinical implications for the treatment of destructive behavior using functional and alternative stimuli.     

Opposite ERP effects for conscious and unconscious semantic processing under continuous flash suppression

We examined whether semantic processing occurs without awareness using continuous flash suppression (CFS). In two priming tasks, participants were required to judge whether a target was a word or a non-word, and to report whether the masked prime was visible. Experiment 1 manipulated the lexical congruency between the prime-target pairs and Experiment 2 manipulated their semantic relatedness. Despite the absence of behavioral priming effects (Experiment 1), the ERP results revealed that an N4 component was sensitive to the prime-target lexical congruency (Experiment 1) and semantic relatedness (Experiment 2) when the prime was rendered invisible under CFS. However, these results were reversed with respect to those that emerged when the stimuli were perceived consciously. Our findings suggest that some form of lexical and semantic processing can occur during CFS-induced unawareness, but are associated with different electrophysiological outcomes.     

Measuring concept semantic relatedness through common spatial pattern feature extraction on EEG signals

We study the semantic relationship between pairs of nouns of concrete objects such as “HORSE - SHEEP” and “SWING - MELON” and how this relationship activity is reflected in EEG signals. We collected 18 sets of EEG records; each set containing 150 events of stimulation. In this work we focus on feature extraction algorithms. Particularly, we highlight Common Spatial Pattern (CSP) as a method of feature extraction. Based on these latter, different classifiers were trained in order to associate a set of signals to a previously learned human answer, pertaining to two classes: semantically related, or not semantically related. The results of classification accuracy were evaluated comparing with other four methods of feature extraction, and using classification algorithms from five different families. In all cases, classification accuracy was benefited from using CSP instead of FDTW, LPC, PCA or ICA for feature extraction. Particularly with the combination CSP-Naïve Bayes we obtained the best average precision of 84.63%.     

Unconscious transfer of meaning to brands

We examine semantic conditioning in a consumer context. We subliminally paired neutral ideographs with attributes. In experiment 1, the ideographs served as primes during a lexical decision task and slowed down response times to target words with the opposite semantic meaning. In experiment 2, the ideographs served as brand names of beverages, and attitudinal responses to them were less favorable when the associated attributes were incongruent with existing schemas. These results showed that semantic conditioning (1) can occur unconsciously, (2) can have significant and meaningful consequences for brand evaluation, and (3) influences subsequent attitudinal responses via conceptual disfluency processes.     

Size matters: Bigger is faster

A largely unexplored aspect of lexical access in visual word recognition is “semantic size”—namely, the real-world size of an object to which a word refers. A total of 42 participants performed a lexical decision task on concrete nouns denoting either big or small objects (e.g., bookcase or teaspoon). Items were matched pairwise on relevant lexical dimensions. Participants' reaction times were reliably faster to semantically “big” versus “small” words. The results are discussed in terms of possible mechanisms, including more active representations for “big” words, due to the ecological importance attributed to large objects in the environment and the relative speed of neural responses to large objects.     

Stimulus/response learning in masked congruency priming of faces: Evidence for covert mental classifications?

Reaction times for categorization of a probe face according to its sex or fame were contrasted as a function of whether the category of a preceding, sandwich-masked prime face was congruent or incongruent. Prime awareness was measured by the ability to later categorize the primes, and this was close to chance and typically uncorrelated with priming. When prime faces were never presented as visible probes within a test, priming was not reliable; when prime faces were also seen as probes, priming was only reliable if visible and masked presentation of faces were interleaved (not simply if primes had been visible in a previous session). In the latter case, priming was independent of experimentally induced face–response or face–category contingencies, ruling out any simple form of stimulus–response learning. We conclude that the reliable masked congruency priming reflects bindings between stimuli and multiple, abstract classifications that can be generated both overtly and covertly.