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Observed human actions are complex and intricate streams of information. We readily process this information in order to understand meanings of actions and hence interact with others. In the same way, language processing involves dealing with information flows and meaning comprehension. We used a neurolinguistic paradigm (N400) to investigate the neural mechanism subtending the visual processing of actions and gestures belonging to the typical basketball game schemes in professional basketball players (as opposed to controls). Two hundred and eight coloured pictures representing basketball players engaged in actions were presented while the EEG was recorded from 24 Italian healthy volunteers (12 basketball players, 12 naïve students), engaged in a secondary perceptual task. Perception of correct and plausible actions (e.g., player shooting a basketball in a correct form) was contrasted with perception of incorrect or meaningless actions (e.g., players with incorrect position of body and or the shooting hands) in the 2 groups (expert players vs. naïve group). Only in basketball players a frontal long negative component (450-530 ms) larger for implausible than plausible actions was observed. This effect possibly reflected their ability to recognize the gesture violation after an assiduous long sporting training during which they learned how to produce correct meaningful gestures and to avoid the incorrect ones. The inverse solution (swLORETA) showed that the processing of incongruent actions in experts was associated with a stronger activity in several areas involved in action processing including the IP cortex, associated with the mental representation of meaningful actions and gestures, and the right FG, right STG and left ITG, all devoted to body and action processing including the action's goal. Overall, the data indicate the existence of a specific neural network allowing the recognition of gesture violations in skilled brains (as a result of the intense sensorimotor training related to sporting practice), similarly to what happens with the acquisition of linguistic rules.

It has been consistently shown that words with high lexical frequencies are recognized more quickly and accurately than words with lower frequencies in the same language. Word frequency has therefore played a central role in the development of lexical processing models. There is increasing behavioral evidence that the age at which words are learned is a variable with as much significance as lexical frequency. Nevertheless, while neuroimaging and electrophysiological studies have provided remarkable evidence of the influence of word frequency on brain activity, little is known about how words acquired earlier or later in life are represented in the brain. The aim of the present study was to investigate whether the processing of early- vs. late-acquired words affects the timing and topographical distribution of ERP components differently than the processing of high- vs. low-frequency words. Participants were asked to perform an orthographic decision task (detection of a target letter) while EEG measurements were taken from 128 scalp sites. The LORETA source localization technique was applied to identify the intracranial generators of the surface potentials. Reaction times showed an effect of both word age of acquisition (AoA) and lexical frequency as well as an interaction between the two psycholinguistic variables. The electrophysiological data revealed a neuro-functional dissociation between AoA and frequency effects in early visual word processing. AoA modulated the amplitude of left occipito-temporal selection negativity, suggesting an effect of word AoA on early orthographic and lexical access and revealing the crucial role of AoA in determining how words are neurally represented in the ventral pathway. Lexical frequency modulated the amplitude of left anterior negativity, providing evidence for the involvement of the left inferior frontal cortex in the processing of low-frequency words.

It is known that infant faces stimulate visual and anterior brain regions belonging to the mesocortical limbic system (orbito-frontal cortex, anterior cingulate cortex, and nucleus accumbens), as well as the fusiform gyrus during face coding, suggesting a preferential response to baby schema. In the present investigation, faces of infants, children, and adults were presented to 40 male and female right-handed university students with technological objects (and inanimate scenarios to serve as targets) in a randomly mixed fashion. EEG was recorded from 128 scalp sites. In both sexes, the N1 response to infant faces was larger than the response to adult faces; however, the baby-specific N1 response was much larger in women than in men across the left hemisphere. The anterior N2 response to infants was greater than the response to children only in women, whereas the response to children of any age was larger than the response to adults in men. LORETA identified the intracranial sources of N2 response to infants in the left fusiform gyrus (FG), as well as the uncus, cingulate, and orbito-frontal (BA11) cortices. The FG, the limbic, and especially the orbito-frontal sources were much larger in women than in men. The data suggest a sex difference in the brain response to faces of different ages and in the preferential response to infants, especially with regard to activation of the mesocorticolimbic system.

As the makers of silent movies knew well, it is not necessary to provide an actual auditory stimulus to activate the sensation of sounds typically associated with what we are viewing. Thus, you could almost hear the neigh of Rodolfo Valentino’s horse, even though the film was mute. Evidence is provided that the mere sight of a photograph associated with a sound can activate the associative auditory cortex. High-density ERPs were recorded in 15 participants while they viewed hundreds of perceptually matched images that were associated (or not) with a given sound. Sound stimuli were discriminated from non-sound stimuli as early as 110 ms. SwLORETA reconstructions showed common activation of ventral stream areas for both types of stimuli and of the associative temporal cortex, at the earliest stage, only for sound stimuli. The primary auditor cortex (BA41) was also activated by sound images after about 200 ms.

The aim of the present study is to investigate the neural bases of the visual spatial attention during the execution of cognitive and motor tasks. Twenty volunteers took part to the experiment. They were all right-handed, healthy and without previous neurologic disorder, with normal or glasses corrected vision; their age ranged between 20 and 35 years; 10 of them were male, 10 female. In this study 2 tasks of the original ANT paradigm version, were used (Fan et al., 2002): the task with the Central Cue and the one with Local Cue; differently from the previous studies, we have added 2 more tasks, the first consists in the execution of a Cognitive task during the performing of the Local Task, this task is called Local Cognitive Cue; the other one consists in a modified version of the ANT's paradigm Local Cue, named Local Motor Cue. The tasks were 4 in total and the subjects should execute the same task as the one of the ANT's paradigm original version, that is they had to discriminate the direction of a central arrow, that was inserted in a series of arrows, by pressing a key; the target could be sorrounded by flankers pointed in the same or in the opposite direction. In the Central Cue task, the arrows were advanced by a non informative cue, in the Local Cue task, the cue was local or informative; in the Local Cognitive Cue task, the subjects should execute the same task as the one of the Local Cue task while doing a cognitive task (counting); finally in the Local Motor task, targets could differ from their direction, their congruence to the flankers and also from their tipe of arrow, so that the subjects had to use 4 fingers instead of 2, to express their decision. Both behavioural (reaction times, number of errors and omissions) and electrophysiological data showed a difference between the tasks; only the behavioural data showed a significative difference between the Congruent and the Incongruent conditions, while the electrophysiological data showed this difference. As for behavioural data, subjects had more difficulties (total errors number and longer response time) in the Local Motor Cue task; while the larger number of omissions was found in the Local Cognitive Cue task. P300 ERP component was found to have a greater maximum amplitude and longer latency for the Motor Cue tasks (6.736 ?V; 456 ms), while in the Central, Local and Local Cognitive Cue tasks, the latency of the component was similar (respectively 398, 399 and 401 ms), but presented a minor amplitude for the Cognitive task (4.509 ?V) related to the other tasks (CC 6.623 ?V; LC 6.196 ?V). SwLORETA revealed different P300 generators in the 4 tasks, in the interval of 315 and 630 ms, with a major amplitude for the Motor Task and with a parietal distribution. The outcomes of statistical analysis on ERPs data and of their intra-cortical generators, found by means of swLORETA source reconstruction technique, support the results of studies suggesting that the resolution of the conflict tasks implies the functioning of the frontal areas, in particular of the lateral prefrontal cortex and of the anterior cingular cortex for the hardest tasks.

There is a lively debate in the literature about the specific roles of the two cerebral hemispheres in processing figurative language. The aim of the present study was to investigate this matter further and to compare the time courses of literal and idiomatic language processing. Fifteen right-handed Italian volunteers were asked to read 360 idiomatic and literal Italian sentences silently and decide whether they were semantically related or unrelated to a following target word, while their EEGs were recorded from 128 scalp sites. Our data indicate bilateral involvement of both hemispheres in idiom comprehension, with a special role for the right hemisphere and particularly the right MTG after 350 ms and the right medial frontal gyrus in the time windows 270-300 and 500-780 ms. In addition, the activation of left and right limbic regions (400-450 ms) suggests that they have a role in the emotional connotation of colourful idiomatic language. The data support the view that there is direct access to the idiomatic meaning of figurative language, not dependent on the suppression of its literal meaning.

BACKGROUND: There is a wide debate in the literature about whether N2/P3 effects in no-go trials reflect the inhibition of an intended action, or the absence of a negative movement-related potential typical of go trials. The aim of this study was to provide an objective measure of the suppression of irrelevant information (in a conjoined selective visual attention task) under conditions that were perfectly comparable from the viewpoint of the motoric processes involved. METHODS: Twenty-nine right-handed students took part in the study. Their EEGs were recorded from 128 scalp sites while they viewed gratings of four different spatial frequencies (from 0.75 to 6 c/deg) randomly flashed in the four upper and lower quadrants of the visual field. The tasks consisted of attending and responding to a conjunction of spatial frequency and space location. Intermediate frequencies (1.5 and 3 c/deg) acted as distracters or lures. Analysis of the ERPs elicited by the same physical stimulus, close in spatial frequency to the actual target and falling within the attended quadrant (pseudo-target) vs. a non-target location, allowed us to identify the time course and neural bases of brain activation during the suppression of irrelevant information. RESULTS: FAs were on average 9% for pseudo-targets and 0.2% for other types of lures, indicating that the former were more difficult to suppress. Target-related ERP components (occipito/temporal selection negativity, posterior P3b and precentral motor N2) were greater to pseudo-targets than other distracters. A large prefrontal negativity (370-430 ms) was also identified, much larger to pseudo-targets than non-targets (and absent in response to real targets), thus reflecting response inhibition and top-down cognitive control processes. CONCLUSIONS: A LORETA inverse solution identified the neural generators of this effect in the left dorsolateral prefrontal cortex (DLPF), left and right fusiform gyri and bilateral superior temporal cortices. The tentative hypothesis is advanced that these activations might reflect the modulatory effects exerted by the fronto/temporal circuit for the suppression of irrelevant information.

BACKGROUND: Neuroimaging and neuropsychological literature show functional dissociations in brain activity during processing of stimuli belonging to different semantic categories (e.g., animals, tools, faces, places), but little information is available about the time course of object perceptual categorization. The aim of the study was to provide information about the timing of processing stimuli from different semantic domains, without using verbal or naming paradigms, in order to observe the emergence of non-linguistic conceptual knowledge in the ventral stream visual pathway. Event related potentials (ERPs) were recorded in 18 healthy right-handed individuals as they performed a perceptual categorization task on 672 pairs of images of animals and man-made objects (i.e., artifacts). RESULTS: Behavioral responses to animal stimuli were ~50 ms faster and more accurate than those to artifacts. At early processing stages (120-180 ms) the right occipital-temporal cortex was more activated in response to animals than to artifacts as indexed by posterior N1 response, while frontal/central N1 (130-160) showed the opposite pattern. In the next processing stage (200-260) the response was stronger to artifacts and usable items at anterior temporal sites. The P300 component was smaller, and the central/parietal N400 component was larger to artifacts than to animals. CONCLUSIONS: The effect of animal and artifact categorization emerged at ~150 ms over the right occipital-temporal area as a stronger response of the ventral stream to animate, homomorphic, entities with faces and legs. The larger frontal/central N1 and the subsequent temporal activation for inanimate objects might reflect the prevalence of a functional rather than perceptual representation of manipulable tools compared to animals. Late ERP effects might reflect semantic integration and cognitive updating processes. Overall, the data are compatible with a modality-specific semantic memory account, in which sensory and action-related semantic features are represented in modality-specific brain areas.

Several studies have provided evidence of a women’s better accuracy in interpreting emotional states. Despite this difference is generally ascribed to the primary role of female gender in the affective relation with the offspring, to date, little information is available regarding gender differences in the ability to interpret infant facial expressions. In the present study, we examined the roles of gender and expertise in interpreting infant expression in 34 men and women who differed in their experience with infants. Women showed a significantly higher level of decoding accuracy compared to men. Expertise positively affected facial expressions decoding among women only. Our results suggest that in judging emotional facial expressions of infants, there is an interaction of biological (i.e., gender) and cultural factors that is independent of a woman’s socioeconomic status.

BACKGROUND: It is known that the orthographic properties of linguistic stimuli are processed within the left occipitotemporal cortex at about 150-200 ms. We recorded event-related potentials (ERPs) to words in standard or mirror orientation to investigate the role of visual word form in reading. Word inversion was performed to determine whether rotated words lose their linguistic properties. METHODS: About 1300 Italian words and legal pseudo-words were presented to 18 right-handed Italian students engaged in a letter detection task. EEG was recorded from 128 scalp sites. RESULTS: ERPs showed an early effect of word orientation at ~150 ms, with larger N1 amplitudes to rotated than to standard words. Low-resolution brain electromagnetic tomography (LORETA) revealed an increase in N1 to rotated words primarily in the right occipital lobe (BA 18), which may indicate an effect of stimulus familiarity. N1 was greater to target than to non-target letters at left lateral occipital sites, thus reflecting the first stage of orthographic processing. LORETA revealed a strong focus of activation for this effect in the left fusiform gyrus (BA 37), which is consistent with the so-called visual word form area (VWFA). Standard words (compared to pseudowords) elicited an enhancement of left occipito/temporal negativity at about 250-350 ms, followed by a larger anterior P3, a reduced frontal N400 and a huge late positivity. Lexical effects for rotated strings were delayed by about 100 ms at occipito/temporal sites, and were totally absent at later processing stages. This suggests the presence of implicit reading processes, which were pre-attentive and of perceptual nature for mirror strings. CONCLUSIONS: The contrast between inverted and standard words did not lead to the identification of a purely linguistic brain region. This finding suggests some caveats in the interpretation of the inversion effect in subtractive paradigms.

While there is a general agreement about the sensory properties of the early-latency C1 (P/N80) and P1 components of visual evoked potentials (VEPs), the literature is not consistent about the timing of modulatory attention effects at an early sensory stage for either space- or object-based stimulus features. The aim of this study was to investigate whether inter-individual differences in VEP morphology might affect the nature and polarity of amplitude changes via selective visual attention. EEG was recorded in 20 right-handed individuals while they viewed drawings of familiar objects presented slightly lateralized and performed a categorization task. It consisted in paying attention and responding to a conjunction of space and object features. On the basis of VEP morphology, and independently of task factors, subjects were subdivided in two groups: one group exhibited a prominent N80 and the other a prominent P80 in the same latency range from the same electrode sites. RTs to targets were identical in the two groups, suggesting that morphology was independent of task-related factors. VEP morphology affected the direction and amplitude of spatial and non-spatial attention effects. While attention effects always resulted in increased positivity for the P80 group (at both the C1 and P1 levels), shape relevance was associated with enhanced N80 and P1 responses in the N80 group. These data provide evidence for an inversion of attention effects, in addition to inversion of C1 polarity, in people exhibiting negative C1 at mesial occipital sites.

This study sought to determine the influence of gender and parental status on the brain potentials elicited by viewing infant facial expressions. We used ERP recording during a judgement task of infant happy/distressed expression to investigate if viewer gender or parental status affects the visual cortical response at various stages of perceptual processing. ERPs were recorded in 38 adults (male/female, parents/non-parents) during processing of infant facial expressions that varied in valence and intensity. All infants were unfamiliar to viewers. The lateral occipital P110 response was much larger in women than in men, regardless of facial expression, thus indicating a gender difference in early visual processing. The occipitotemporal N160 response provided the first evidence of discrimination of expressions of discomfort and distress and demonstrated a significant gender difference within the parent group, thus suggesting a strong interactive influence of genetic predisposition and parental status on the responsivity of visual brain areas. The N245 component exhibited complete coding of the intensity of facial expression, including positive expressions. At this processing stage the cerebral responses of female and male non-parents were significantly smaller than those of parents and insensitive to differences in the intensity of infant suffering. Smaller P300 amplitudes were elicited in mothers versus fathers, especially with infant expressions of suffering. No major group differences were observed in cerebral responses to happy or comfortable expressions. These findings suggest that mere familiarity with infant faces does not explain group differences.

Neuroimaging studies have provided evidence that the orthographic properties of linguistic stimuli are processed within the visual word form area (VWFA) localised in the left inferotemporal cortex (Cohen & Dehaene, 2004). It is not, however, clear in the literature whether this region responds preferentially to words, distinguishing them from pseudowords, or whether the pseudowords are distinguished from letter-strings on the basis of their orthographic regularity, or again, whether the VWFA distinguishes letters from numbers or from visual stimuli such as chequerboards. Very recently, it has been claimed that there is no evidence that the ill-named VWFA changes its responsiveness during or after reading acquisition (Price & Devlin, 2004). In order to simulate a condition of pre-reading ability in adult readers, we performed this study, in which we compared processing of Greek words and legal pseudowords in mother-tongue Greeks (skilled readers) and monolingual Italian individuals (naive readers) who had no familiarity with the Greek alphabet. ERPs were recorded while volunteers were engaged in a task involving the identification and response to target letters contained within Greek words or pseudowords. The response speed was identical in the two groups (550 vs. 557 ms). ERP data showed that at 165 ms post-stimulus (N1 component) the left lateral-occipital scalp area, probably corresponding to the left ventral occipitotemporal sulcus, discriminates letters of a familiar alphabet, while an unknown alphabet also activates the homologous right-hemispheric region more than 100 ms later. This suggests that the VWFA discriminates nonalphabetic symbols from letter-strings. An analysis of the N2 component showed an increase in the activation of the same region at about 285 ms post-stimulus during the processing of words rather than pseudowords in skilled readers, thus supporting the view that the VWFA discriminates words on the basis of their familiarity. The data seem to suggest that the VWFA is alphabet-specific and that it is based on the shaping of visual area activity during acquisition of the ability to read a given symbolic code.

Current cognitive neuroscience models predict a right-hemispheric dominance for face processing in humans. However, neuroimaging and electromagnetic data in the literature provide conflicting evidence of a right-sided brain asymmetry for decoding the structural properties of faces. The purpose of this study was to investigate whether this inconsistency might be due to gender differences in hemispheric asymmetry. RESULTS: In this study, event-related brain potentials (ERPs) were recorded in 40 healthy, strictly right-handed individuals (20 women and 20 men) while they observed infants' faces expressing a variety of emotions. Early face-sensitive P1 and N1 responses to neutral vs. affective expressions were measured over the occipital/temporal cortices, and the responses were analyzed according to viewer gender. Along with a strong right hemispheric dominance for men, the results showed a lack of asymmetry for face processing in the amplitude of the occipito-temporal N1 response in women to both neutral and affective faces. CONCLUSION: Men showed an asymmetric functioning of visual cortex while decoding faces and expressions, whereas women showed a more bilateral functioning. These results indicate the importance of gender effects in the lateralization of the occipito-temporal response during the processing of face identity, structure, familiarity, or affective content.

The development of reading skills is a complex and very long-lasting process. In an influential study Booth et al. demonstrated age-related changes in the activation of a network of left hemisphere regions, including the inferior frontal area, the superior temporal gyrus, and the angular gyrus. Interestingly, they found that the angular gyrus, which is involved in the mapping between phonological and orthographic representation, is automatically activated in adults during visual orthographic tasks not requiring this operation.

Recent event-related potential (ERP) and neuroimaging studies suggest that bilingual individuals are able to inhibit the processing of a non-target language while speaking or reading in another language. The neural mechanisms subserving code switching still remain matter of debate. The aim of the present study was to shed some light on the neurofunctional bases of such mechanisms. ERPs were recorded in native Italian simultaneous interpreters and monolingual controls during a semantic processing task in which the subjects had to evaluate the sensibleness of final words of incomplete sentences. All participants were strictly right-handed. Interpreters knew at least four languages (from four to eight) at a professional level, from among 11 European and Asian languages, and had an excellent command of English (L2). Four hundred short sentences were presented visually; half of them had an unexpected final word, producing a semantic incongruence. Sentences could be entirely in Italian or in English (unmixed); alternatively, the body of the sentence could be in English and the final word in Italian or vice versa (mixed). ERPs were time locked to the onset of the final word. Both reaction times (RTs) and electrophysiological data indicated a lesser degree of hemispheric lateralization for linguistic function during L2 rather than L1 processing in interpreters. The first effect of lexical switching and code switching was recorded in the time window between 140 and 200 ms at left anterior sites. At N400 level, ERPs were significantly larger to L2 than to L1 words only in the mixed and not in the unmixed condition. No effect of language was observed in the unmixed condition, thus suggesting that the difference in L1/L2 processing was not related to a difference in proficiency, but rather to a different functional organization of semantic integration systems due to the later age of acquisition of L2 compared to L1. Interpreters were faster at reading and comprehending sentences in English ending with an Italian word than vice versa (L2 --> L1 switch).

The goal of the study was to investigate how the color and shape of visual stimuli are processed when they are conjointly presented and represent real, and familiar, entities for which normal individuals presumably have a specific 'object color knowledge' (e.g., piglets are pink, artichokes are green). There is evidence, from event related potential (ERP) literature on selective attention to color in conjunction with other, arbitrarily related, stimulus dimensions (e.g., geometrical shape), that color is processed faster than shape, and that the processing of shape depends on color relevance. In this study we recorded ERPs from 28 scalp sites in right-handed volunteers performing selective attention tasks to either color or shape of pictures representing familiar objects and animals. The results revealed that the selection of color was faster, and probably less demanding, than that of shape. However, it was also evidenced that the selection of color depended on object shape, but not vice versa. Indeed, in the attend-color condition, the N2 responses were significantly greater when stimulus shape was prototypically associated, rather than unassociated, with the color perceived. Topographical mapping of difference voltages identified the posterior occipito/temporal region of the left hemisphere as the possible locus of conjoined color and shape processing. Overall, the data support object-based attention models.

Marzi and colleagues described the case of two partially acallosal patients, suggesting that their interhemispheric transfer in a Poffenberger paradigm could be mediated by slow subcortical routes. Some discrepancies between the CUD in RTs and visual event-related potentials (ERPs), along with a dishomogeneity in lesion locus, make it difficult to compare the data of the two patients and draw any straightforward conclusion. We present ERP data of a commissurotomized patient engaged in selective attention tasks to lateralized patterned stimuli. These data provide evidence of a delayed synchronized evoked response affected by stimulus eccentricity over the disconnected nonviewing hemisphere, probably mediated by collicular subcortical pathways.