Auditory perception of temporal and spectral events in patients with focal left and right cerebral lesions

The auditory perception of temporal and spectral information was studied in subjects with lesions in the temporoparietal region of the left (LH group), or right (RH group) hemisphere (n = 5 in each group) and in five normal controls. The temporal tasks included gap detection and two complex pattern perception tasks in which subjects had to identify the placement of the two closest tones (separated by the shortest interval) within a sequence of six tones. The spectral tasks involved pitch matching and frequency discrimination. The results showed a "double dissociation": (1) the LH group was impaired in their ability to perceive temporal information, but the perception of spectral information was normal, and (2) the RH group was impaired in their ability to perceive spectral information, but the perception of temporal information was normal. The findings are consistent with the notion that temporal processing is a function of left-hemisphere structures and that spectral processing is a function of right-hemisphere structures.     

Sentence processing in children with early unilateral brain injury

This study examined how children use word order and animacy cues to determine the agent of the action in an on-line sentence-comprehension task. The subject group included 15 children, 5-12 years old, with brain injury incurred prior to the age of 2 months; 12 had left hemisphere (LH) damage and 3 had right hemisphere (RH) damage. The comparison group included 141 children, 5-10 years old, who were at the appropriate grade for age. The task required children to listen to sentences composed of two noun phrases (N) that varied in terms of animacy and a verb phrase (V) and then to indicate the agent of the action. Three word orders were presented: NVN, VNN, and NNV. Measures included the proportion of trials in which the first noun was selected (choice) and reaction time. Word order and animacy significantly influenced choice. The effect of subject group approached significance for choice. Word order and age influenced reaction time. The children with LH injury and two children with RH injury showed a developmental delay in choosing the appropriate N as agent; one child with RH injury had mature responses. The overlapping performance of children with LH and RH injury suggests that delays in the development of sentence comprehension strategies are more likely related to reliance on a smaller than usual neural network rather than to congenital specialization of the LH.     

Preliminary evidence for impaired rapid verb generation in schizophrenia

It has been hypothesized that nouns and verbs are processed within relatively separable semantic memory networks. Although abnormal semantic processing is a common feature of schizophrenia-spectrum disorders, no prior studies have specifically examined the comparability of noun and verb generation deficits in schizophrenia. In the current study, verb (action), noun (animal), and letter (f) fluency performance was evaluated in 22 inpatients with schizophrenia and 27 healthy comparison subjects. On average, individuals with schizophrenia performed approximately one standard deviation below the healthy comparison subjects on action, animal, and letter fluency. Action fluency-but not letter or animal fluency-was moderately correlated with tests of working memory, response inhibition, semantic memory, and cognitive flexibility. Findings suggest that verb- and noun-based fluency deficits are of comparable severity in schizophrenia, but that the impairment in verb generation may be driven by different underlying cognitive mechanisms. Further, hypothesis-driven research on the nature and extent of verb network disruption in schizophrenia appears warranted.     

汉语名词、动词和动名兼类词语义加工的偏侧化现象——来自ERP的研究

将ERP技术和半视野技术相结合,采用词汇判断任务,对汉语名词、动词和动名兼类词在左脑和右脑中的加工机制进行了考察。实验结果显示,名词和动词的N400仅在左视野/右脑存在差异,名词和动词的N400在左视野/右脑和右视野/左脑中都比偏（动）和偏（名）更负。不同词类的LPC在右视野/左脑中没有显著差异;偏（名）和偏（动）的LPC在左视野/右脑中比名词和动词更正。实验结果表明,在没有语境条件下,汉语名词和动词的差异主要在具体性上,动名兼类词体现出不同于名词、动词的加工机制。     

Verb retrieval in brain-damaged subjects: 1. Analysis of stimulus, lexical, and conceptual factors

Verb retrieval for action naming was assessed in 53 brain-damaged subjects by administering a standardized test with 100 items. The goal of the study was to gain further insight into the nature of verb processing impairments by investigating the influence of several kinds of stimulus, lexical, and conceptual factors on the subjects' performance at the level of group tendencies and also at the level of individual differences. (1) Stimulus factors: visual complexity, familiarity, image agreement, and one vs. two pictures (which corresponds to ongoing vs. completed actions); (2) lexical factors: name agreement, verb frequency, and whether the root of the target verb has a homophonous noun; (3) conceptual factors: whether the action is done with the hand or the body, whether the action involves one or two core participants, whether the undergoer of the action has a change of internal state, whether the undergoer has a change of spatial location, and whether the actor makes use of an instrument in carrying out the action. The subjects were divided into an impaired group (n = 19) and an unimpaired group (n = 34) on the basis of their overall performance on the test. For both groups of subjects, verb retrieval was significantly affected by the following factors: familiarity, image agreement, name agreement, homophonous noun, and undergoer change of location. These results indicate that, at the level of group analysis, some factors have a stronger influence on verb retrieval for action naming than others. Moreover, the finding that the two groups exhibited the same general pattern of factor sensitivity suggests that although the processing efficiency of the mechanisms that subserve verb retrieval is degraded in the impaired group, the basic functional properties of these mechanisms may not be qualitatively very different from those of the unimpaired group. Further analyses were conducted at the level of individual subjects and revealed a considerable amount of variation with regard to factor sensitivity. Many patterns of associations and dissociations of factors were found across the subjects, which suggests that the task of retrieving verbs for naming actions is quite complex and that different subjects can be influenced by different properties of both the stimuli and the target verbs.     

Priming nouns and verbs: differential influences of semantic and grammatical cues in the two cerebral hemispheres

The current experiment investigated how sentential form-class expectancies influenced lexical-semantic priming within each hemisphere. Sentences were presented that led readers to expect a noun or a verb and the sentence-final target word was presented to one visual field/hemisphere for a lexical decision response. Noun and verb targets in the semantically related condition were compared to an unrelated prime condition, which also predicted part of speech but did not contain any lexical-semantic associates of the target word. The semantic priming effect was strongly modulated by form-class expectancy for RVF/LH targets, for both nouns and verbs. In the LVF/RH, semantic priming was obtained in all conditions, regardless of whether the form-class expectancy was violated. However, the nouns that were preceded by a noun-predicting sentence showed an extremely high priming value in the LVF/RH, suggesting that the RH may have some sensitivity to grammatical predictions for nouns. Comparisons of LVF/RH priming to calculations derived from the LSA model of language representation, which does not utilize word order, suggested that the RH might derive message-level meaning primarily from lexical-semantic relatedness.     

The impact of left and right intracranial tumors on picture and word recognition memory

This study investigated the effects of left and right intracranial tumors on picture and word recognition memory. We hypothesized that left hemispheric (LH) patients would exhibit greater word recognition memory impairment than right hemispheric (RH) patients, with no significant hemispheric group picture recognition memory differences. The LH patient group obtained a significantly slower mean picture recognition reaction time than the RH group. The LH group had a higher proportion of tumors extending into the temporal lobes, possibly accounting for their greater pictorial processing impairments. Dual coding and enhanced visual imagery may have contributed to the patient groups' similar performance on the remainder of the measures.     

A place for nouns and a place for verbs? A critical review of neurocognitive data on grammatical-class effects

It is generally held that noun processing is specifically sub-served by temporal areas, while the neural underpinnings of verb processing are located in the frontal lobe. However, this view is now challenged by a significant body of evidence accumulated over the years. Moreover, the results obtained so far on the neural implementation of noun and verb processing appear to be quite inconsistent. The present review briefly describes and critically re-considers the anatomo-correlative, neuroimaging, MEG, TMS and cortical stimulation studies on nouns and verbs with the aim of assessing the consistency of their results, particularly within techniques. The paper also addresses the question as to whether the inconsistency of the data could be due to the variety of the tasks used. However, it emerged that neither the different investigation techniques used nor the different cognitive tasks employed fully explain the variability of the data. In the final section we thus suggest that the main reason for the emergence of inconsistent data in this field is that the cerebral circuits underlying noun and verb processing are not spatially segregated, at least for the spatial resolution currently used in most neuroimaging studies.     

The return of “visiting relatives”: Pragmatic effects in sentence processing

Two experiments were performed to investigate the role of syntactic and pragmatic cues on the disambiguation of noun phrases of the form VERB+ing NOUN+s, like visiting relatives, that can be interpreted as either singular or plural noun phrases. Both experiments used a self-paced reading task in which reading times were measured for two words, a verb and an adverb, immediately following the potentially ambiguous noun phrase. The interpretation of the noun phrase as singular or plural was biased by pragmatic cues in the first experiment and by syntactic cues in the second experiment. In both experiments, subjects were faster to read the adverb following the verb when the interpretation biased by the cues agreed in number with the verb that immediately followed the target noun phrase than when it did not agree with the verb. These results suggest that pragmatic cues, like syntactic cues, can be utilized rapidly in sentence processing.     

Linearity and morphological structure in derived words: evidence from category decision.

The present article investigates the influences of word-internal category information and linearity on the processing of morphologically complex words. Three sets of Finnish derived nouns consisting of a noun, adjective or verb stem, and a suffix were submitted to two on-line category decision tasks, where the subjects had to decide whether the word was a noun or a verb respectively. Both experiments show a stem-suffix category mismatch effect manifesting itself in prolonged reaction time latencies. Thus, the results indicate that the order of presentation and the word-internal structural information are intimately tied together also in the visual processing of morphological complex words.     

阅读理解中汉语量词的眼动特点分析

采用眼动记录技术探讨被试阅读不同汉语量词的即时加工过程。考查名量词和动量词,以及名量词内部的差异。结果发现:(1)被试在阅读理解过程中对名量词和动量词的眼动特点存在显著差异,名量词获得更多的加工;(2)被试在阅读理解过程中对不同名量词的眼动特点也存在显著差异,个体量词比集合量词和临时量词获得更少的加工。由此可知,不同量词在阅读理解中的信息加工难度是不同的,对于篇章理解而言,其信息含量和信息的重要性也是不同的。     

The contribution of the right cerebral hemisphere to the recovery from aphasia: a single longitudinal case study

We examined the role of the right cerebral hemisphere in the recovery from aphasia of HJ, a 50-year-old right-handed and unilingual man who suffered from severe aphasia caused by an extensive left hemisphere (LH) lesion. He was followed-up over 10 months at 4-month intervals, with a lateralized lexical decision task (LDT), an attentional task, and a language battery. Testing started when HJ was 2 months poststroke. In the LDT, words were presented to central vision or lateralized to the left or right visual hemifield. At each test period, we examined the effect of the degree of imageability (high vs. low), and the grammatical class (noun vs. verb) of the targets on HJ's response times and error rates, with left visual field, right visual field, and central vision presentations. The results of the experiment showed that the pattern obtained with the LDT could not be accounted for by fluctuations in attention. There was an interaction of grammatical class with degree of imageability with left visual field displays only. The right hemisphere (RH) was faster with high-imageability words than with low-imageability words, regardless of their grammatical class. There was also an overall RH advantage on response times at 2 and 6 months after onset. This RH predominance coincided with a major recovery of language comprehension and the observation of semantic paralexias, while no major change in language expression was observed at that point. Ten months after onset, the pattern of lateralization changed, and response times for the LDT with either presentation site were equivalent. This LH improvement coincided with some recovery of language expression at the single-word level. The results of this study suggest that, in cases of severe aphasia caused by extensive LH lesions, the RH may play an important role in the recovery process. Furthermore, these results show that the contribution of the two cerebral hemispheres to recovery may vary overtime and affect specific aspects of language.     

When nominal features are marked on verbs: a transcranial magnetic stimulation study

It has been claimed that verb processing (as opposed to noun processing) is subserved by specific neural circuits in the left prefrontal cortex. In this study, we took advantage of the unusual grammatical characteristics of clitic pronouns in Italian (e.g., lo and la in portalo and portala 'bring it [masculine]/[feminine]', respectively)-the fact that clitics have both nominal and verbal characteristics, to explore the neural correlates of verb and clitic processing. We used repetitive transcranial magnetic stimulation (rTMS) to suppress the excitability of the left prefrontal cortex and to assess its role in producing verb+det+noun and verb+clitic phrases. Results showed an interference effect for both kinds of phrases when stimulation was applied to the left but not to the right prefrontal cortex. However, the interference effect was significantly greater for the verb+clitic than for the verb+det+noun phrases. These findings support the view that clitics increase the morphosyntactic complexity of verbs.     

Semantic facilitation and lexical access during sentence processing: An investigation of individual differences

An earlier experiment (Blank & Foss, 1978) showed that the time required to access the object noun of a sentence was shortened if the noun was preceded by a semantically related verb or adjective. When both the verb and the adjective were semantically related to the noun, the amount of facilitation of lexical access was additive. However, additivity appeared to break down for subjects who did poorly on the comprehension test administered in that experiment, suggesting that the activation function among related lexical items was different for good and poor comprehenders. Such a finding would have implications for theories of lexical facilitation, especially the two-factor theories such as the one proposed by Posner and Snyder (1975). The present experiment again measured access time for the object noun of a sentence when it was preceded by an unrelated or a related verb or adjective (four sentence types). Two groups of college subjects were tested, relatively good (N = 63) and relatively poor (N = 42) comprehenders. The difference in the time taken to retrieve the object noun was ascertained by measuring reaction time to respond to the initial phoneme of the next word in the sentence (phoneme monitoring technique). Reaction times were shorter when the noun was preceded by a semantically related word; the effects of two sources of related context (verb and adjective) appeared to be additive forboth groups of subjects. These results were discussed within the context of two-factor theories of lexical activation and within the context of Morton’s (1969) logogen model.     

The influence of semantic fit on on-line sentence processing

The interactive influence of verb complement preferences and noun phrase semantic fit on resolution of temporary syntactic ambiguity was investigated in an eye movement experiment. The present semantic fit manipulation included noun phrases that fit well as direct objects of the verbs that they followed and noun phrases that were possible but less likely direct objects of the verbs in question. This contrasted with existing research on the use of verb complement preferences and semantic fit during sentence processing, in which processing of noun phrases that are possible direct objects has been compared with processing of noun phrases that are not possible direct objects of the verbs that they follow. Verb complement preference information and noun phrase semantic fit interacted at early stages of on-line sentence processing. Implications of these results for interactive and structural models of sentence processing are discussed.     

Relative Clause Effects at the Matrix Verb Depend on Type of Intervening Material

Although a large literature demonstrates that object-extracted relative clauses (ORCs) are harder to process than subject-extracted relative clauses (SRCs), there is less agreement regarding where during processing this difficulty emerges, as well as how best to explain these effects. An eye-tracking study by Staub, Dillon, and Clifton (2017) demonstrated that readers experience more processing difficulty at the matrix verb for ORCs than for SRCs when the matrix verb immediately follows the relative clause (RC), but the difficulty is eliminated if a prepositional phrase (PP) intervenes. A careful examination of Staub et al.’s materials reveals that the types of PPs used in the experiment were a mixture of locative and temporal PPs. This is important in that locative PPs can modify either a noun phrase or a verb phrase (VP), whereas temporal PPs typically modify VPs, resulting in systematic differences in PP attachment across ORCs versus SRCs. In the current eye-tracking experiment, we systematically manipulated RC type and PP type in the same sentences used by Staub et al. The manipulation of PP type resulted in a crossover pattern at the matrix verb such that there was a trend for reading times to be longer for ORCs than SRCs when the PP was locative, but reading times were longer for SRCs than ORCs when the PP was temporal. These results provide important information regarding the locus of RC-processing effects and highlight the importance of carefully considering how intervening material might unintentionally alter the structure or the meaning of a sentence.     

Perceptual asymmetry for chimeric stimuli in children with early unilateral brain damage

The present study used a chimeric stimuli task to assess the magnitude of the left-hemispace bias in children with congenital unilateral brain damage (n = 46) as compared to typically developing matched controls (n = 46). As would be expected, controls exhibited a significant left-hemispace bias. In the presence of left hemisphere (LH) damage, the left-hemispace preference was found to be present, but attenuated, whereas right hemisphere (RH) damage resulted in a less lateralized process. Examination of lesion severity revealed that large lesions in the RH were associated with a reversal of the typical left-hemispace bias, while small lesions resulted in a left bias approximating that of controls. In contrast, the left-hemispace preference in children with LH damage was similar across lesion size. We conclude that damage to either hemisphere early in brain development may alter hemispheric preference for processing of nonverbal stimuli, and that at least in the case of RH damage, alteration of the normal perceptual asymmetry may depend on the interaction between lesion side and severity.     

Alteration of expected hemispheric asymmetries: valence and arousal effects in neuropsychological models of emotion

The relative advantage of the left (LH) over the right hemisphere (RH) in processing of verbal material for most individuals is well established. Nevertheless, several studies have reported the ability of positively and negatively valenced stimuli to enhance and reverse, respectively, the usual LH>RH asymmetry. These studies, however, have used baseline stimuli that differed from emotional stimuli on two dimensions (i.e., valence and verbal/nonverbal nature), creating interpretive difficulties as to whether differences across these conditions are due to differences in valence or the verbal/nonverbal nature of the primes used in the baseline condition. In addition, these studies, along with many others in the literature, have failed to control for potential confounding effects of arousal. Emotional stimuli vary on dimensions of valence as well as arousal and arousal may be asymmetrically presented in the brain therefore contributing to observed asymmetries. Taken together, these considerations underscore the importance of controlling for both valence as well as arousal in any investigation of the effects of emotional stimuli. The objectives of the present study were twofold: (1) to employ an appropriate baseline condition to render emotional stimuli vs. baseline stimuli comparisons meaningful and (2) to examine the extent to which emotional verbal stimuli, equated for arousal level, alter the expected LH>RH asymmetry in a consonant trigram task. Results demonstrated that when LH lateralized consonant trigram presentations were preceded by a positive prime, an enhancement of the expected LH>RH asymmetry was observed. In contrast, when trigram presentations lateralized to the RH were preceded by a negative prime, a complete reversal of the typical asymmetry was found with RH>LH performance. These results are analogous to the pattern of relative hemispheric activations observed for various mood states. Controlling for arousal in studies investigating asymmetries associated with emotional processing may allow more clear interpretation of data intended to test predictions of neuropsychological models of emotion. Moreover, equating stimuli on the dimension of arousal as well as valence may shed more light on conflicting findings with regard to perception vs. expression of emotion.     

Grammatical category ambiguity in aphasia

This study asked whether aphasic adults show different noun/verb retrieval patterns based upon their clinical categorization as fluent or nonfluent. Participants selected either the noun or the verb meaning of target words, as presented in three contexts. The framework was that nouns (associated with temporal lobe function) are processed, stored, and retrieved separately from verbs (associated with frontal lobe function), implying separate status in the mental lexicon. Stimuli were homophonic homographs, words that are spelled and pronounced the same but which have different meanings (in this case, noun and verb meanings). Another contrast was the putative difference between systematic pairs (e.g., "kiss" and "farm"), in which noun and verb meanings are transparently related, and may be stored as a unit, and unsystematic pairs (e.g., "squash" and "sink"), in which noun and verb meanings are apparently unrelated, implying discrete storage. Results demonstrated significant interactions between fluent and nonfluent participants, suggesting that, as expected, fluent aphasic adults have more difficulty with nouns, nonfluent aphasic adults have more difficulty with verbs. There was no effect of systematicity. Contrary to expectations, verbs proved less vulnerable, rather than more vulnerable, to aphasic impairment.