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The lexical representation of compound words in speech production is still under debate. While most studies with healthy adult speakers suggest that a single lemma representation is active during compound production, data from neuropsychological studies point toward multiple representations, with activation of the compound's constituent lemmas in addition to the compound's lemma. This study exploits the cumulative semantic interference effect to investigate the lexical representation of compounds in speech production. In a continuous picture naming experiment, category membership was established through the compounds' first constituents (category animals: "'zebra' crossing," "'pony' tail," "'cat' litter" …), while the compounds themselves were not semantically related. Moreover, pictures depicting the compounds' first constituents ("zebra," "pony," "cat" …) were presented as a control condition. As expected, naming latencies within categories increased linearly with each additionally named category member when producing monomorphemic words, which is interpreted as increasing interference during lexical selection. Importantly, this cumulative semantic interference effect was also observed for compounds. This indicates that the lemmas of the compounds' first constituents were activated during compound production, causing interference due to their semantic relationship and thereby hampering the production of the whole compound. The results are thus in line with the multiple-lemma representation account (Marelli et al., 2012). We argue that the apparent contradiction between results of previous studies with healthy adult speakers and our current study can be explained by the different experimental paradigms used.

Background: Alexithymia is a risk factor for major depressive disorder (MDD) and has been associated with diminished treatment response. Neuroimaging studies have revealed structural aberrations of the anterior cingulate cortex and the fusiform gyrus in healthy controls with high levels of alexithymia. The present study tried to corroborate and extend these results to patients with MDD compared with healthy controls. Methods: We investigated the relationship between alexithymia, depression and grey matter volume in 63 patients with MDD (mean age [+ or -] standard deviation = 42.43 yr [+ or -] 11.91; 33 female) and 46 healthy controls (45.35 yr [+ or -] 8.37; 22 female). We assessed alexithymia using the Toronto Alexithymia Scale. We conducted an alexithymia x group analysis of covariance; we used a region-of-interest approach, including the fusiform gyrus and anterior cingulate cortex, and conducted whole brain analysis using voxel-based morphometry. Results: Our analysis revealed a significant alexithymia x group interaction in the fusiform gyrus (left, [p.sub.FWE] = 0.031; right, [p.sub.FWE] = 0.010). Higher alexithymia scores were associated with decreased grey matter volume in patients with MDD ([p.sub.FWE] = 0.009), but with increased grey matter volume of the fusiform gyrus in healthy controls ([p.sub.FWE] = 0.044). We found no significant main effects in the region-of-interest analysis. Limitations: Owing to the naturalistic nature of our study, patients with MDD and healthy controls differed significantly in their alexithymia scores. Conclusion: Our results showed the fusiform gyrus as a correlate of alexithymia. We also found differences related to alexithymia between patients with MDD and healthy controls in the fusiform gyrus. Our study encourages research related to the transition from risk to MDD in people with alexithymia., Introduction Major depressive disorder (MDD) is one of the most common and disabling psychiatric diseases worldwide. (1) At least one-third of patients with MDD do not respond to first-line treatment, [...]

Increased automatic processing of threat-related stimuli has been proposed as a key element in panic disorder. Little is known about the neural basis of automatic processing, in particular to task-irrelevant, panic-related, ecologically valid stimuli, or about the association between brain activation and symptomatology in patients with panic disorder. Methods: The present event-related functional MRI (fMRI) study compared brain responses to task-irrelevant, panic-related and neutral visual stimuli in medication-free patients with panic disorder and healthy controls. Panic-related and neutral scenes were presented while participants performed a spatially nonoverlapping bar orientation task. Correlation analyses investigated the association between brain responses and panic-related aspects of symptomatology, measured using the Anxiety Sensitivity Index (ASI). Results: We included 26 patients with panic disorder and 26 heatlhy controls in our analysis. Compared with controls, patients with panic disorder showed elevated activation in the amygdala, brainstem, thalamus, insula, anterior cingulate cortex and midcingulate cortex in response to panic-related versus neutral task-irrelevant stimuli. Furthermore, fear of cardiovascular symptoms (a subcomponent of the ASI) was associated with insula activation, whereas fear of respiratory symptoms was associated with brainstem hyperactivation in patients with panic disorder. Limitations: The additional implementation of measures of autonomic activation, such as pupil diameter, heart rate, or electrodermal activity, would have been informative during the fMRI scan as well as during the rating procedure. Conclusion: Results reveal a neural network involved in the processing of panic-related distractor stimuli in patients with panic disorder and suggest an automatic weighting of panic-related information depending on the magnitude of cardiovascular and respiratory symptoms. Insula and brainstem activations show function-related associations with specific components of panic symptomatology., Introduction Recurring sudden panic attacks and anxious apprehension are the 2 core symptoms for diagnosing panic disorder. (1) Panic-related anxious apprehension is characterized by worry about future attacks and by [...]

We report two picture-word interference experiments investigating conceptual and lexical activation, and response selection, in speaking. We varied stimulus onset asynchrony to investigate potential fine-grained activation and competition effects. Morphologically related existing and pseudoword adjectives, as well as associatively related adjectives, served as context stimuli in Experiment 1. In Experiment 2, we focused on semantic interference by using morphologically related and unrelated subordinates of the target concept as context stimuli. Morphologically complex pseudowords were also included as context stimuli. Pseudowords should not interfere, given that they have no lexical or conceptual representation. We consistently obtained facilitation with all morphologically related context stimuli, irrespective of their lexical status. We argue that effects originate at the word-form level, and discuss how our results may help decide among the many explanations of semantic interference in picture naming.

This study investigated the nature of the retrieval architecture of Semitic morphemic entities in word production in Hebrew, a language with a non-concatenated morphology. By taking advantage of the potential for dissociation of form and meaning in Hebrew, we explored the relative contribution of word-form and semantics to morphological processing. In two picture-word interference (PWI) experiments we investigated the lexical status of the two primary morphemes: the root and the word pattern (WP), with the effects of morphological, phonological and semantic relatedness between written distractors and picture names. Facilitation effects were observed for both the root and the WP. Moreover, neither semantic nor phonological similarity affected picture naming in the absence of a morphological relation. Although both the root and the WP induced equally robust morphological effects, we postulate a typical and distinct processing mechanism for each type of morpheme. We interpret our findings as evidence for a parallel processing mechanism of morphemic entities, which is implemented in part at the lemma level and in part at the lexeme level, where the output of both processes is integrated. Implications of these findings for the retrieval architecture of morphemic entities are discussed. (Contains 4 tables and 1 figure.)

We investigated whether and when information conveyed by spoken language impacts on the processing of visually presented objects. In contrast to traditional views, grounded-cognition posits direct links between language comprehension and perceptual processing. We used a magnetoencephalographic cross-modal priming paradigm to disentangle these views. In a sentence-picture verification task, pictures (e.g. of a flying duck) were paired with three sentence conditions: A feature-matching sentence about a duck in the air, a feature-mismatching sentence about a duck in a lake, and an unrelated sentence. Brain responses to pictures showed enhanced activity in the N400 time-window for the unrelated compared to both related conditions in the left temporal lobe. The M1 time-window revealed more activation for the feature-matching than for the other two conditions in the occipital cortex. These dissociable effects on early visual processing and semantic integration support models in which language comprehension engages two complementary systems, a perceptual and an abstract one. (Contains 2 figures.)

Recently, an increasing number of studies have suggested a role for the basal ganglia and related dopamine inputs in procedural learning, specifically when learning occurs through trial-by-trial feedback (Shohamy, Myers, Kalanithi, & Gluck. (2008). "Basal ganglia and dopamine contributions to probabilistic category learning." "Neuroscience and Biobehavioral Reviews," 32, 219-236). A necessary relationship has however only been demonstrated in patient studies. In the present study, we show for the first time that increasing dopamine levels in the brain improves the gradual acquisition of complex information in healthy participants. We implemented two artificial-grammar-learning tasks, one with and one without performance feedback. Learning was improved after levodopa intake for the feedback-based learning task only, suggesting that dopamine plays a specific role in trial-by-trial feedback-based learning. This provides promising directions for future studies on dopaminergic modulation of cognitive functioning. (Contains 2 figures.)

This study investigated whether German participles are retrieved as whole words from lexical storage or whether they are accessed via their morphemic constituents. German participle formation is of particular interest, since it is concatenative for both regular and irregular verbs and results from combinations of regular/irregular stems with regular/irregular suffixes. Data from visual priming showed that regular and irregular participles facilitated their base verbs to the same degree, which argues against different processing systems. Furthermore, "illegal combinations" of participle affixes and verbal or nonverbal stems ("geworft," "gewurft") were as effective as correct participles ("geworfen") in facilitating the morphologically related base verb ("werfen"). This indicates that stems contained in illegal combinations were accessed, regardless of whether they originated from regular or irregular verbs. These findings strongly argue for a single system that processes both regular and irregular inflection via access to morphemic constituents. Such a single processing model is suggested.

Two experiments are reported in which university students translated visually presented English words into German, while German distractor words were simultaneously presented. Distractors were morphologically related, merely form-related or unrelated to the German translations (target words). The transparency of the semantic relation between target words and morphological distractors was also varied. Morphological distractors facilitated word-translation latencies irrespective of their semantic transparency, replicating results obtained with other tasks. Thus, in German word production, effects of morphological complexity seem to be largely independent of semantics. Morphological facilitation is also not due to mere form relatedness, since phonological distractors had no impact on translation latencies, relative to unrelated distractors. The data corroborates the usefulness of word-translation for investigating spoken word production, in particular, for morphological processing. The following are appended: (1) t-test values for Participant and Item analyses Experiment 1; and (2) Material Experiment 1 (English translation in parentheses). (Contains 2 tables.)

The authors examined whether people can use their knowledge of the wider discourse rapidly enough to anticipate specific upcoming words as a sentence is unfolding. In an event-related brain potential (ERP) experiment, subjects heard Dutch stories that supported the prediction of a specific noun. To probe whether this noun was anticipated at a preceding indefinite article, stories were continued with a gender-marked adjective whose suffix mismatched the upcoming noun's syntactic gender. Prediction-inconsistent adjectives elicited a differential ERP effect, which disappeared in a no-discourse control experiment. Furthermore, in self-paced reading, prediction-inconsistent adjectives slowed readers down before the noun. These findings suggest that people can indeed predict upcoming words in fluent discourse and, moreover, that these predicted words can immediately begin to participate in incremental parsing operations.

We examined the contribution of semantic similarity to morphological priming effects, using the immediate (Exp. 1 and 3) and the delayed variant (Exp. 2) of picture-word interference. Distractor words were either compounds morphologically related to the picture name, but differing with respect to their semantic transparency (hummingbird, jailbird (Exp. 1); butterfly, butter dish (Exp. 3)), or form-related non-compound words (e.g., trombone). All three experiments revealed strong facilitation of picture naming due to morphologically related distractors. Form-related distractors facilitated picture naming in the immediate variant only, and to a lesser degree than compounds. Interestingly, the size of the morphemic effect was almost identical for semantically transparent and opaque complex words, which suggests that they share morphemic representations. These results suggest that morphological complexity in speech production is coded at the level of form representations, independent of semantic transparency.

Three experiments investigated the impact of syllabic boundary information and of morphological structure on performance in a sequence-monitoring task. In sequence monitoring, participants detect pre-specified sequences of phonemes in spoken carrier words. Sequences corresponded to the first syllable of the carrier word, to its first morpheme, or simultaneously to both. The data from Experiments 1 and 2, using different variants of the monitoring task, showed a strong impact of syllable boundary cues on monitoring latencies. An effect of morphological match between targets and carrier words was also evident. Experiment 3, in which parts of the spoken carrier words were cross-spliced, revealed that syllabic boundary information takes precedence over morphological information. The results are in line with an early process of speech processing, in which syllabic cues are used to aid lexical access. The morphological effect is better understood as a later, probably lexical, contribution of morphological decomposition to monitoring performance.

Data are presented from crossmodal form priming experiments in German on regressive and progressive assimilation at word boundaries. Results show that some, but not all forms of lawful variation are tolerated by the lexical system. Consequences of these findings for psycholinguistic and linguistic models are discussed. (Author/VWL)

Investigated the influence of morphologically complex and simple words on the production of morphologically complex and simple picture names in five picture-word interference studies. Two variants of picture-word interference were employed to separate morphological from semantic and phonological effects. (Author/VWL)

Background: Altered memory processes are thought to be a key mechanism in the etiology of anxiety disorders, but little is known about the neural correlates of fear learning and memory biases in patients with social phobia. The present study therefore examined whether patients with social phobia exhibit different patterns of neural activation when confronted with recently acquired emotional stimuli. Methods: Patients with social phobia and a group of healthy controls learned to associate pseudonames with pictures of persons displaying either a fearful or a neutral expression. The next day, participants read the pseudonames in the magnetic resonance imaging scanner. Afterwards, 2 memory tests were carried out. Results: We enrolled 21 patients and 21 controls in our study. There were no group differences for learning performance, and results of the memory tests were mixed. On a neural level, patients showed weaker amygdala activation than controls for the contrast of names previously associated with fearful versus neutral faces. Social phobia severity was negatively related to amygdala activation. Moreover, a detailed psychophysiological interaction analysis revealed an inverse correlation between disorder severity and frontolimbic connectivity for the emotional > neutral pseudonames contrast. Limitations: Our sample included only women. Conclusion: Our results support the theory of a disturbed corticolimbic interplay, even for recently learned emotional stimuli. We discuss the findings with regard to the vigilance-avoidance theory and contrast them to results indicating an oversensitive limbic system in patients with social phobia., Introduction Social phobia is one of the most prevalent and burdensome anxiety disorders. (1) In addition to threat-focused information processing, early experiences and learning mechanisms are assumed to constitute a [...]