Inter- and intra- hemispheric interactions in reading ambiguous words.

The present study investigated how the brain processes words with multiple meanings. Specifically, we examined the inter- and intra-hemispheric connectivity of unambiguous words compared to two types of ambiguous words: homophonic homographs, which have multiple meanings mapped to a single phonological representation and orthography, and heterophonic homographs, which have multiple meanings mapped to different phonological representations but the same orthography. Using a semantic relatedness judgment task and effective connectivity analysis via Dynamic Causal Modeling (DCM) on previously published fMRI data (Bitan et al., 2017), we found that the two hemispheres compete in orthographic processing during the reading of unambiguous words. For heterophonic homographs, we observed increased connectivity within the left hemisphere, highlighting the importance of top-down re-activation of orthographic representations by phonological ones for considering alternative meanings. For homophonic homographs, we found a flow of information from the left to the right hemisphere and from the right to the left, indicating that the brain retrieves different meanings using different pathways. These findings provide novel insights into the complex mechanisms involved in language processing and shed light on the different communication patterns within and between hemispheres during the processing of ambiguous and unambiguous words.

Interactions of lexical and conceptual representations: Evidence from EEG.

We examined whether meanings automatically activate linguistic forms, and whether these forms affect semantic decisions. Participants were presented sequentially with pairs of pictures and decided whether the objects in the pictures were related. At no point did they name the pictures. The object names of the experimental stimuli were ambiguous either in orthography (homographs), phonology (homophones), or both (homonyms), or unambiguous. We show that the lexical characteristics of the name of the objects affect a semantic decision about real world relations, in an online measure (N400), in addition to offline behavioral measures. We show a dissociation between conceptual and lexical recognition, where an earlier component (N230), was affected by relatedness, but was not sensitive to the lexical characteristics. We interpret this as supporting the hypothesis that semantic recognition occurs before the automatic lexical activation of the object name, but that once linguistic representations are activated, they affect semantic integration.

Competition in context: response selection within the supervisory attentional system model.

We examined the effects of context bias and target exposure duration on error rates (ERR) and response times (RTs) in letter choice task within context. Surface Electromyography (sEMG) was recorded in both hands during context presentation, as a measure of readiness to respond. The goal was to affect the outcome of the task by manipulating relative schemata activation levels prior to target onset, as per the Supervisory Attentional System model. At short exposures, context bias and sEMG activity affected ERR, whereas at longer durations, RTs were affected. Context bias mediated the effect of sEMG activity. Increasing activity in both hands led to higher ERR and RTs in incongruent context. Non-increasing activity in the non-responding lead to lack of relationship between sEMG activity and behavior, irrespective of context. sEMG activity in both hands was found to be interrelated and context-sensitive. These results conform to the predictions of the Supervisory Attentional Model.

Interhemispheric transfer of visual information: Meaningfulness and response formation.

We examined whether Redundancy Gain (RG) can be dissociated from the response stage of a go/nogo paradigm, and whether the meaningfulness of a stimulus modulates the stage at which interhemispheric transfer occurs. Experiment 1 used a lateralized match-to-category paradigm, taken from categories with varying meaningfulness. Experiment 2 presented a novel design, which separates the perceptual stage from response formation, in examination of RG. A sequence of two stimuli was presented. Participants responded by matching the category of the second stimulus to that of the first. The redundant stimulus could appear at the first or the second stage, thus redundancy gain could be separated from the response. Experiment 1 revealed that redundancy gain occurs earlier in the process of stimulus identification for highly meaningful stimuli than for less meaningful stimuli. The results of Experiment 2 support the hypothesis that redundancy gain results from interhemispheric integration of perceptual information, rather than response-formation. Results from both experiments suggest that redundancy gain arises from interhemispheric integration in the perceptual stage, and the efficiency of this integration depends on the meaningfulness of the stimulus. These results are relevant to current hypotheses about the physiological mechanisms underlying RG.

Handedness in the presence of prior knowledge: Effects of interhemispheric configuration on performance.

The current study examined the effects of prior knowledge of the responding hand, and that of errors, on the configuration of interhemispheric balance. Prior knowledge was manipulated by instructing the participants to respond with one hand throughout a session (Blocked) or to select the responding hand according to the identity of the stimulus in each trial (Mixed). In addition, we examined how failures to inhibit responses within Logan's (1981) Stop Signal Response Task (SSRT) task affected the Response Times (RTs) of subsequent correct responses. The SSRT was modified to include visual stop signals, shown in Divided Visual Field (DVF), in order to examine the effects of errors committed by each hemisphere. The effects of prior knowledge were shown by absence of a dominant hand effect in the Blocked condition but were uniformly present in the Mixed condition. We also show that commission of an error in the peripheral VFs differentially affected subsequent RTs only in the absence of prior knowledge. We conclude that prior knowledge shifts interhemispheric configuration from the default dominance model to a more complex cooperative configuration.

Phonology and orthography in deaf readers: Evidence from a lateralized ambiguity resolution paradigm.

This study explored differences between the two hemispheres in processing written words among deaf readers. The main hypothesis was that impoverished phonological abilities of deaf readers may lead to atypical patterns of hemispheric involvement. To test this, deaf participants completed a metalinguistic awareness test to evaluate their orthographic and phonological awareness. Additionally, they were asked to read biased or neutral target sentences ending with an ambiguous homograph, with each sentence followed by the request to make a rapid lexical decision on a target word presented either to the left (LH) or right hemisphere (RH). Targets were either related to the more frequent, dominant, meaning of the homograph, to the less frequent, subordinate, meaning of the homograph or were not related at all. An Inverse Efficiency Score based on both response latency and accuracy was calculated and revealed that deaf readers' RH perform better than their LH. In contrast to hearing readers who in previous studies manifested left hemisphere dominance when completed the same research design. The apparent divergence of deaf readers' hemisphere lateralization from that of hearing counterparts seems to validate previous findings suggesting greater reliance on RH involvement among deaf individuals during visual word recognition.

Expressive writing - Who is it good for? Individual differences in the improvement of mental health resulting from expressive writing.

OBJECTIVE: we examined individual differences in the effects of expressive writing. We hypothesized that moderate levels of neuroticism, low levels of experiential avoidance, and highly rated subjective severity would be linked to greater change in well-being post-writing. DESIGN: participants were randomly assigned to the expressive group (N = 104) who wrote about emotion-laden experiences, or the control group (N = 51) who wrote about everyday events. All completed the IES and BSI pre and 1, 3, and 6 weeks post-writing. RESULTS: overall, we replicated the seminal result, with greater reductions in IES scores in the expressive writing group. In addition, in the expressive group, as expected, participants with higher severity scores had greater reductions in BSI scores. Surprisingly, individuals with high rather than moderate neuroticism and high rather than low experiential avoidance scores also experienced more benefit. CONCLUSIONS: participants who are more aware of, in touch with, and suffer more from negative feelings are those who gain the most from expressive writing. Based on this conclusion, clinical implications relevant to both psychotherapy patients and non-patients are suggested.

Semantic and affective manifestations of ambi (valence).

People sometimes report both pleasant and unpleasant feelings when presented with affective stimuli. However, what is reported as "mixed emotions" might reflect semantic knowledge about the stimulus (Russell, J. A. (2017). Mixed emotions viewed from the psychological constructionist perspective. Emotion Review, 9(2), 111-117). The following research examines to what degree self-reported mixed emotions represent actual feelings compared to knowledge about the stimulus. In a series of three experiments, participants reported either their feelings or their knowledge in response to affective stimuli. In Experiment 1, we sampled the entire IAPS pictorial space and examined the proportion of mixed emotion ratings using feelings-focused and knowledge-focused self-reports. We found a higher degree of mixed emotions under knowledge-focused than feelings-focused self-reports. In Experiment 2, we used a priori selected pictures to elicit mixed emotions. The proportion of mixed emotions was again higher under knowledge-focused instructions. In Experiment 3, we used movie clips that were previously used to elicit mixed emotions. In contrast to Experiments 1 and 2, there was no difference between feelings-focused and knowledge-focused self-reports. The results suggest a strong semantic component and a weak experiential component of self-reports in the case of pictorial stimuli. However, ambivalent movie clips elicited a stronger experiential component, thus supporting the existence of mixed emotions at the level of feelings.

Separability of Lexical and Morphological Knowledge: Evidence from Language Minority Children.

Lexical and morphological knowledge of school-aged children are correlated with each other, and are often difficult to distinguish. One reason for this might be that many tasks currently used to assess morphological knowledge require children to inflect or derive real words in the language, thus recruiting their vocabulary knowledge. The current study investigated the possible separability of lexical and morphological knowledge using two complementary approaches. First, we examined the correlations between vocabulary and four morphological tasks tapping different aspects of morphological processing and awareness, and using either real-word or pseudo-word stimuli. Thus, we tested the hypothesis that different morphological tasks recruit lexical knowledge to various degrees. Second, we compared the Hebrew vocabulary and morphological knowledge of 5th grade language minority speaking children to that of their native speaking peers. This comparison allows us to ask whether reduced exposure to the societal language might differentially influence vocabulary and morphological knowledge. The results demonstrate that indeed different morphological tasks rely on lexical knowledge to varying degrees. In addition, language minority students had significantly lower performance in vocabulary and in morphological tasks that recruited vocabulary knowledge to a greater extent. In contrast, both groups performed similarly in abstract morphological tasks with a lower vocabulary load. These results demonstrate that lexical and morphological knowledge may rely on partially separable learning mechanisms, and highlight the importance of distinguishing between these two linguistic components.

Phonological ambiguity modulates resolution of semantic ambiguity during reading: An fMRI study of Hebrew.

OBJECTIVES: The current fMRI study examined the role of phonology in the extraction of meaning from print in each hemisphere by comparing homophonic and heterophonic homographs (ambiguous words in which both meanings have the same or different sounds respectively, e.g., bank or tear). The analysis distinguished between the first phase, in which participants read ambiguous words without context, and the second phase in which the context resolves the ambiguity. METHOD: Native Hebrew readers were scanned during semantic relatedness judgments on pairs of words in which the first word was either a homophone or a heterophone and the second word was related to its dominant or subordinate meaning. RESULTS: In Phase 1 there was greater activation for heterophones in left inferior frontal gyrus (IFG), pars opercularis, and more activation for homophones in bilateral IFG pars orbitalis, suggesting that resolution of the conflict at the phonological level has abolished the semantic ambiguity for heterophones. Reduced activation for all ambiguous words in temporo-parietal regions suggests that although ambiguity enhances controlled lexical selection processes in frontal regions it reduces reliance on bottom-up mapping processes. After presentation of the context, a larger difference between the dominant and subordinate meaning was found for heterophones in all reading-related regions, suggesting a greater engagement for heterophones with the dominant meaning. CONCLUSIONS: Altogether these results are consistent with the prominent role of phonological processing in visual word recognition. Finally, despite differences in hemispheric asymmetry between homophones and heterophones, ambiguity resolution, even toward the subordinate meaning, is largely left lateralized. (PsycINFO Database Record

Controlled semantic processes within and between the two cerebral hemispheres.

To test the separate and combined abilities of the two cerebral hemispheres to perform controlled semantic selection and integration processes, Hebrew readers saw pairs of words and had to decide whether the two words were semantically related. The first word in each pair was presented centrally. The second word was presented in the left, right, or central visual field (LVF, RVF, and CVF). We compared response latencies for related pairs in two conditions: In the ambiguous condition, the first word was a homograph (either homophonic or heterophonic) and the second word was related to either its dominant or subordinate meaning. In the unambiguous condition, homographs were replaced with unambiguous control words. Irrespective of VF or homograph type, response times for ambiguous pairs were significantly longer than for unambiguous pairs only when targets were related to the subordinate meaning of the homograph. In the left hemisphere (RVF/LH), this ambiguity effect was larger for heterophones than for homophones, whereas in the right hemisphere (LVF/RH), similar patterns were observed for both types of homographs. Finally, performance patterns in the CVF revealed the same patterns as those in the RVF/LH, and were different from those in the LVF/RH. The implications of these results are discussed.

The neural bases of the learning and generalization of morphological inflection.

Affixal inflectional morphology has been intensively examined as a model of productive aspects of language. Nevertheless, little is known about the neurocognition of the learning and generalization of affixal inflection, or the influence of certain factors that may affect these processes. In an event-related fMRI study, we examined the neurocognition of the learning and generalization of plural inflections in an artificial language, as well as the influence of both affix type frequency (the proportion of words receiving a given affix) and affix predictability (based on phonological cues in the stem). Adult participants were trained in three sessions, and were scanned after the first and last sessions while inflecting trained and untrained words. Untrained words yielded more activation than trained words in medial frontal (including pre-SMA) and left inferior frontal cortices, which have previously shown activation in compositional grammatical processing. A reliance on phonological cues for untrained word inflection correlated positively with pre-SMA activation, but negatively with activation in the pars triangularis. Thus, pre-SMA may be involved in phonological cue-based composition, while the pars triangularis underlies alternative processes. Inflecting trained items yielded activation in the caudate head bilaterally, only in the first session, consistent with a role for procedural memory in learning grammatical regularities. The medial frontal and left inferior regions activated by untrained items were also activated by trained items, but more weakly than untrained items, with weakest activation for trained-items taking the high-frequency affix. This suggests less involvement of compositional processes for inflecting trained than untrained items, and least of all for trained inflected forms with high-frequency affixes, consistent with the storage of such forms (e.g., in declarative memory). Overall, the findings further elucidate the neural bases of the learning and generalization of affixal morphology, and the roles of affix type frequency and affix phonological predictability in these processes. Moreover, the results support and further specify the declarative/procedural model, in particular in adult language learning.

The Role of Emergent Bilingualism in the Development of Morphological Awareness in Arabic and Hebrew.

PURPOSE: The purpose of the present study was to investigate the role of dual language development and cross-linguistic influence on morphological awareness in young bilinguals' first language (L1) and second language (L2). We examined whether (a) the bilingual children (L1/L2 Arabic and L1/L2 Hebrew) precede their monolingual Hebrew- or Arabic-speaking peers in L1 and L2 morphological awareness, and (b) 1 Semitic language (Arabic) has cross-linguistic influence on another Semitic language (Hebrew) in morphological awareness. METHOD: The study sample comprised 93 six-year-old children. The bilinguals had attended bilingual Hebrew-Arabic kindergartens for 1 academic year and were divided into 2 groups: home language Hebrew (L1) and home language Arabic (L1). These groups were compared to age-matched monolingual Hebrew speakers and monolingual Arabic speakers. We used nonwords similar in structure to familiar words in both target languages, representing 6 inflectional morphological categories. RESULTS: L1 Arabic and L1 Hebrew bilinguals performed significantly better than Arabic- and Hebrew-speaking monolinguals in the respective languages. Differences were not found between the bilingual groups. We found evidence of cross-linguistic transfer of morphological awareness from Arabic to Hebrew in 2 categories-bound possessives and dual number-probably because these categories are more salient in Palestinian Spoken Arabic than in Hebrew. CONCLUSIONS: We conclude that children with even an initial exposure to L2 reveal acceleration of sensitivity to word structure in both of their languages. We suggest that this is due to the fact that two Semitic languages, Arabic and Hebrew, share a common core of linguistic features, together with favorable contextual factors and instructional factors.

Lexical factors in conceptual processes: The relationship between semantic representations and their corresponding phonological and orthographic lexical forms.

To examine phonological and orthographic effects on semantic processing, the present study utilized a semantic task with nonverbal stimuli. In Experiment 1, Hebrew speakers were asked to decide whether 2 pictorial targets are semantically related or not. In Experiment 2, Hebrew speakers and non-Hebrew speakers were asked to rate the semantic relatedness of the same targets on a 5-point scale. Experiment 3 was identical to the first experiment except that the 2 pictures were presented simultaneously rather than sequentially. In all experiments, we compared responses to semantically unrelated pairs in 2 conditions: In the ambiguous condition, each pair represented 2 distinct meanings of an ambiguous Hebrew word. In the unambiguous condition, the first picture was replaced with an unambiguous control. To disentangle phonological and orthographic effects, three types of Hebrew ambiguous words were used: homonyms, homophones, and homographs. Ambiguous pairs were more difficult to be judged as semantically unrelated in comparison to their unambiguous controls. Moreover, while non-Hebrew speakers did not distinguish between the 2 lexical conditions, Hebrew speakers rated ambiguous pairs as significantly more related than their unambiguous controls. Importantly, in general, the ambiguity effect was stronger for homonyms, where both lexical forms are shared, than for either homophones or homographs, which are only phonologically or orthographically related. Thus, consistent with interactive "triangle" models, the results suggest that (a) conceptual-semantic representations automatically activate both their corresponding phonological and orthographic lexical forms, and (b) these lexical forms, once activated, may in turn affect semantic-conceptual processes via feedback connections.

Language-specific and language-general factors in text reading in arabic: evidence from the missing letter effect

The goal of the present study was to extend the models explaining the missing-letter effect (MLE) to an additional language and orthography, and to test the role of phonology in silent reading in Arabic. We also examined orthographic effects such as letter position and letter shape, morphological effects such as pseudo-prefixes, and phonological effects such as pronounceability. The results showed that readers miss letters more often in function words and prefixes than in content words, more in second position than in first position, more often when the letters are silent than pronounced, and less often when the letter shape is more symmetric and stable. The results show that these aspects of the missing letter effect can be generalized over writing systems that are not alphabetic, suggesting that the models proposed to explain the MLE in all the orthographies tested may reflect a universal aspect of reading (AU)

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The missing link in the embodiment of syntax: prosody.

Neurolinguistic theories are challenged by the amodal abstract representations assumed by linguists. Embodied linguistics offers a conceptualization of the relationship between linguistic representation, experience, and the brain. Findings correlating brain activation patterns with referential features of words (e.g., body parts), suggest that the mechanism underlying linguistic embodiment is an "action-perception simulation". This mechanism accounts for embodied representation of words, but is harder to adapt to syntactic abstractions. We suggest that prosody is the missing link. Prosody is a sensory-motor phenomenon that can evoke an "action-perception simulation" that underpins the syntax-experience-brain association. Our review discusses different embodiment models and then integrates psycholinguistic and neurocognitive studies into a new approach to linguistic embodiment. We propose a novel implementation of the syntax-experience-brain relationship via the mapping between the temporo-spectral aspects of speech prosody and temporo-spectral patterns of synchronized behavior of neural populations. We discuss the potential implications for psycho- and neuro-linguistic research.

Fact retrieval and memory consolidation for a movement sequence: bidirectional effects of 'unrelated' cognitive tasks on procedural memory.

The generation of long-term memory for motor skills can be modulated by subsequent motor experiences that interfere with the consolidation process. Recent studies suggest that even a non-motor task may adversely affect some aspects of motor sequence memory. Here we show that motor sequence memory can be either enhanced or reduced, by different cognitive tasks. Participants were trained in performing finger movement sequences. Fully explicit instructions about the target sequence were given before practice. The buildup of procedural knowledge was tested at three time-points: immediately before training (T1), after practice (T2), and 24 hours later (T3). Each participant performed the task on two separate occasions; training on a different movement sequence on each occasion. In one condition, interference, participants performed a non-motor task immediately after T2. Half the participants solved simple math problems and half performed a simple semantic judgment task. In the baseline condition there was no additional task. All participants improved significantly between T1 and T2 (within-session gains). In addition, in the baseline condition, performance significantly improved between T2 and T3 (delayed 'off-line' gains). Solving math problems significantly enhanced these delayed gains in motor performance, whereas performing semantic decisions significantly reduced delayed gains compared to baseline. Thus, procedural motor memory consolidation can be either enhanced or inhibited by subsequent cognitive experiences. These effects do not require explicit or implicit new learning. The retrieval of unrelated, non-motor, well established knowledge can modulate procedural memory.

Hemispheric asymmetries in meaning selection: evidence from the disambiguation of homophonic vs. heterophonic homographs.

Research investigating hemispheric asymmetries in meaning selection using homophonic homographs (e.g., bank), suggests that the left hemisphere (LH) quickly selects contextually relevant meanings, whereas the right hemisphere (RH) maintains a broader spectrum of meanings including those that are contextually irrelevant (e.g., Faust & Chiarello, 1998). The present study investigated cerebral asymmetries in maintaining the multiple meanings of two types of Hebrew homographs: homophonic homographs and heterophonic homographs (e.g., tear). Participants read homographs preceded by a biasing, or a non-biasing sentential context, and performed a lexical decision task on targets presented laterally, 1000ms after the onset of the sentence-final ambiguous prime. Targets were related to either the dominant or the subordinate meaning of the preceding homograph, or unrelated to it. When targets were presented in the LVF/RH, dominant and subordinate meanings, of both types of homographs, were retained only when they were supported by context. In a non-biasing context, only dominant meanings of homophonic homographs were retained. Alternatively, when targets were presented in the RVF/LH, priming effects for homophonic homographs were only evident when meanings were supported by both context and frequency (i.e., when context favored the dominant meaning). In contrast, heterophonic homographs resulted in activation of dominant meanings, in all contexts, and activation of subordinate meanings, only in subordinate-biasing contexts. The results challenge the view that a broader spectrum of meanings is maintained in the right than in the left hemisphere and suggest that hemispheric differences in the time course of meaning selection (or decay) may be modulated by phonology.

The contribution of the two hemispheres to lexical decision in different languages.

BACKGROUND: Both reading words and text in Arabic is slower than in other languages, even among skilled native Arabic speakers Previously we have shown that the right hemisphere (RH) had difficulty in matching Arabic letters, and suggested that it cannot contribute to word recognition in Arabic. In this study we tested this finding directly. METHOD: We used the Divided Visual Field (DVF) lexical decision (LD) paradigm to assess hemispheric function during reading. The experiment had two conditions (unilateral and bilateral). In the unilateral condition, the target stimulus was presented unilaterally to the left or the right visual field. In the bilateral condition two stimuli were presented simultaneously, and participants were cued as to which one was the target. Three groups of participants were tested: Arabic speakers, Hebrew speakers, and English speakers. Each group was tested in their native language. RESULTS: For Hebrew and English speakers, performance in both visual fields was significantly better in the unilateral than in the bilateral condition. For Arabic speakers, performance in the right visual field (RVF, where stimuli are presented directly to the left hemisphere) did not change in the two conditions. Performance in the LVF (when stimuli are presented directly to the right hemisphere) was at chance level in the bilateral condition, but not in the unilateral condition. CONCLUSION: We interpret these data as supporting the hypothesis that in English and Hebrew, both hemispheres are involved in LD, whereas in Arabic, the right hemisphere is not involved in word recognition.

Perception of emotion and bilateral advantage in women with eating disorders, their healthy sisters, and nonrelated healthy controls.

BACKGROUND: Eating disorders (EDs) are characterized not only by disordered eating, but also by other psychopathology. In this exploratory study, we examined the ability of women with different diagnoses of EDs, their unaffected sisters, and healthy unrelated controls to recognize their own and other's emotions. We also looked at interhemispheric integration of emotion recognition and its relationship with depression. METHOD: Five groups of women participated: 1. anorexia nervosa restricting (AN-R) and 2. (AN-B/B) binge/purge, 3. bulimia nervosa binge/purge, (BN-B/P), 4. healthy sisters of women with ED, and 5. unrelated healthy controls. We used two questionnaires measuring alexithymia and depression, and two lateralized experimental tasks requiring recognition of facial emotion. Unilateral versus bilateral presentation allow the indexing of interhemispheric integration. RESULTS: Alexithymia: All the ED groups were found to be more alexithymic and depressed on the self report scales compared to the two healthy groups. Depression completely mediated alexithymia in the AN-R group but not in the AN-B/P and BN-B/P patients. Sisters of ED women were more alexithymic than unrelated controls. Lateralized facial emotion recognition: ED women showed no deficits in recognizing basic emotions. However, the clinical groups did not show a bilateral advantage whereas the two healthy groups did so. CONCLUSIONS: We present three conclusions: we show, for the first time, evidence for a deficit in hemispheric integration in EDs. This implies that EDs may be a disconnection syndrome; alexithymia characterizes women with EDs and members of their family; depression is manifested differently in AN-R, than in women who binge/purge.