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.     

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.     

Neoclassical Economics and the Last Dogma of Positivism: Is the Normative-Positive Distinction Justified?

Neoclassical economic theory in its pretensions to scientific status is founded on one of the variants of a now discredited positivism. Neoclassical economic theory claims that there are two distinct areas of economic research: positive economics and normative economics. The former is assumed to deal with the cognitive as scientific content of economics while the later focuses on welfare or equity issues. I argue that the reliance of the whole theoretical structure of economics on the normative postulate of rationality renders neoclassical economics a normative discipline. I also argue that neoclassical economics should thus be viewed as an instance of applied ethics rather than as applied mathematics, say. Finally, it is suggested that neoclassical economics, if its scientific pretensions are to be taken seriously, should be absorbed theoretically into general anthropology.     

Moral Accountancy and Moral Worth

People do good or bad things, and get or do not get good or bad credit for their actions, depending (in part) on knowledge of their actions. I attempt to unfold some of the interconnections between these matters, and between them and the achievement of moral worth. The main conclusion is that the heights of moral worth seem to appear in the oddest places.     

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.     

Variation in individuals' semantic networks for common knowledge is associated with false memory

Three experiments assessed the relationships between false memories of words and their degree of connectedness within individual semantic networks. In the first two experiments, participants studied associated word lists (e.g., hot, winter, ice), completed a recognition test that included related nonstudied words (e.g., cold, snow), and then rated the semantic relatedness of all word pairs including studied and nonstudied words. In the third experiment, the task order was reversed; participants completed pairwise ratings and then, two weeks later, completed the false memory task. The relatedness ratings were analysed using the Pathfinder scaling algorithm. In all experiments, items that an individual falsely recognized had higher semantic Pathfinder node densities than those items correctly rejected.