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There is evidence of maladaptive attentional biases for lexical information (e.g., Atchley, Ilardi, & Enloe, 2003; Atchley, Stringer, Mathias, Ilardi, & Minatrea, 2007) and for pictographic stimuli (e.g., Gotlib, Krasnoperova, Yue, & Joormann, 2004) among patients with depression. The current research looks for depressotypic processing biases among depressed out-patients and non-clinical controls, using both verbal and pictorial stimuli. A d' measure (sensitivity index) was used to examine each participant's perceptual sensitivity threshold. Never-depressed controls evidenced a detection bias for positive picture stimuli, while depressed participants had no such bias. With verbal stimuli, depressed individuals showed specific decrements in the detection of positive person-referent words (WINNER), but not with positive non-person-referent words (SUNSHINE) or with negative words. Never-depressed participants showed no such differences across word types. In the current study, depression is characterised both by an absence of the normal positivistic biases seen in individuals without mood disorders (consistent with McCabe & Gotlib, 1995), and by a specific reduction in sensitivity for person-referent positive information that might be inconsistent with depressotypic self-schemas.

The individual roles played by the cerebral hemispheres during the process of language comprehension have been extensively studied in tasks that require individuals to read text (for review see Jung-Beeman, 2005). However, it is not clear whether or not some aspects of the theorized laterality models of semantic comprehension are a result of the modality of presentation. Extending earlier work examining lateralized semantic processing using lexically ambiguous words, the current experiments utilized two modified lexical-decision tasks (one fully auditory and one cross-modal) with dichotically presented target stimuli. When targets were presented to the right ear/left hemisphere there was a distinct advantage for detecting words that are associated with the dominant meaning of the ambiguous word over the subordinate meaning. In contrast, for left ear/right hemisphere trials, there was either no difference between the pattern of semantic access for dominant and subordinate meaning (dichotic only) or a processing advantage for the subordinate meaning of the ambiguous word (with cross-modal presentation). These data suggest that the complimentary hemispheric strategies that allow for semantic access are not modality specific and instead characterize how the hemispheres each contribute to comprehension for both speech and text. Thus, dichotic presentation does seem to allow for the study of subtle hemispheric difference in meaning comprehension., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Positive schizotypal traits have been associated with right hemisphere activation. Previous research has indicated that the left and right hemispheres differ in their processing of semantic ambiguity; specifically, given sufficient time, the left hemisphere primes dominant meanings and inhibits subordinate meanings, and the right hemisphere primes both dominant and subordinate meanings. The authors examined whether individuals who differed in positive schizotypy demonstrated different patterns of priming on a semantic ambiguity task, reflective of differences in hemispheric activation. Individuals low in schizotypy demonstrated the expected pattern of priming the dominant meaning while inhibiting the subordinate meaning. Individuals high in schizotypy demonstrated similar priming of the dominant meaning but no inhibition of the subordinate meaning. The role of this failure of inhibition in the generation of schizotypal thought is discussed., (Copyright 2009 APA, all rights reserved.)

The present study employs event related potentials (ERPs) to verify the utility of using electrophysiological measures to study developmental questions within the field of language comprehension. Established ERP components (N400 and P600) that reflect semantic and syntactic processing were examined. Fifteen adults and 14 children (ages 8-13) processed spoken stimuli containing either semantic or syntactic anomalies. Adult participants showed a significant N400 in response to semantic anomalies and P600 components in response to syntactic anomalies. Children also show evidence of both ERP components. The children's N400 component differed from the adults' in scalp location, latency, and component amplitude. The children's P600 was remarkably similar to the P600 shown by adults in scalp location, component amplitude, and component latency. Theoretical implication for theories of language comprehension in adults and children will be discussed.

Event-related potentials (ERPs) were used as the dependent measure in a divided visual field study examining the processing of lexically ambiguous words in the cerebral hemispheres. The goal was to determine if the N400 ERP component is sensitive measure of hemispheric differences in semantic processing. ERP waveforms were examined for lateralized target words that were related to either the dominant (MONEY) or subordinate (RIVER) meanings of ambiguous words (BANK). These waveforms were compared to trials where the prime-target pairs were unrelated. Reliable N400s, reflecting a significant difference between related and unrelated trials, were seen when targets were presented to the right visual field/left hemisphere. However, there were no N400s observed for either the dominant or subordinate conditions when targets were presented to the left visual field/right hemisphere.

Psuedohomophones are nonwords that sound like real words (e.g., BRANE). These items were used to gauge phonological access in adults who have experienced developmental language processing deficits (DLD). The standard effect for these items in lexical decision is an increase in response times over nonpseudohomophone nonwords. This disadvantage reflects phonological processing. In our first experiment the DLD group did not produce this pseudohomophone effect whereas in a second experiment they showed semantic priming effects when pseudohomophones were used as primes in lexical decision. The results therefore indicate that phonological processing of nonwords by adults with DLD can be uncovered under certain carefully controlled experimental conditions.

A divided visual field (DVF) experiment examined the semantic processing strategies employed by the cerebral hemispheres to determine if strategies observed with written word stimuli generalize to other media for communicating semantic information. We employed picture stimuli and vary the degree of semantic relatedness between the picture pairs. Participants made an on-line semantic relatedness judgment in response to sequentially presented pictures. We found that when pictures are presented to the right hemisphere responses are generally more accurate than the left hemisphere for semantic relatedness judgments for picture pairs. Furthermore, consistent with earlier DVF studies employing words, we conclude that the RH is better at accessing or maintaining access to information that has a weak or more remote semantic relationship. We also found evidence of faster access for pictures presented to the LH in the strongly-related condition. Overall, these results are consistent with earlier DVF word studies that argue that the cerebral hemispheres each play an important and separable role during semantic retrieval. (Contains 4 figures and 2 tables.)

Two experiments were conducted to determine if the right hemisphere (RH) plays a central role in understanding sarcasm. In Experiment 1, 48 participants completed a target detection task using dichotically presented phrases that were sincere (message compatible), sarcastic (conflicting semantic and prosodic message), or neutral (no emotional prosody). Sarcastic phrases presented to the left ear (LE)/RH produced faster response times than sarcastic phrases presented to the right ear/left hemisphere. Accuracy results indicated an overall LE/RH advantage for detecting both sarcastic and sincere phrases. Experiment 2 utilized the same task with the addition of event-related potential recording. There was a reliable N400 seen in response to the sarcastic phrases, but only with LE/RH presentation. These results suggest that the RH is particularly sensitive to the mismatch between semantic and prosodic information characterized by sarcasm. [ABSTRACT FROM PUBLISHER]