Story processing in right-hemisphere brain-damaged patients.

The understanding of stories requires sensitivity to structural aspects of narrative, the emotional content conveyed by the narrative, and the interaction between structural and emotional facets of the story. Right-hemisphere-damaged (RHD) and normal control subjects performed a number of different analytic tasks which probed their competence at story comprehension. Results revealed that RHD subjects perform at a level comparable to that of normal controls with stories that follow a canonical form and that they show few difficulties with structural aspects of narrative. Contrary to expectation, they are strongly influenced by the "interest" level of a story and by other factors that tap emotional sensitivity. Findings are discussed in terms of the processing and arousal mechanisms which may give rise to the observed pattern of difficulties in RHD patients.     

Characteristics of recovery of drawing ability in left and right brain-damaged patients

Drawings of a "person" were obtained from 21 patients with left brain damage (LBD) and 13 patients with right brain damage (RBD) at hospital discharge and 1 month postdischarge, corresponding to 2-4 and 6-8 weeks postonset, respectively. Early LBD drawings were simplistic and often incoherent. Most were placed in the upper left quadrant of the page. RBD drawings were scattered, fragmented, and elaborately detailed. Many showed evidence of left-sided neglect. The resolution of drawing disability also differed between the two groups: LBD subjects recovered drawing abilities more rapidly and more completely than RBD subjects. These differences in drawing characteristics and in the resolution of drawing disability were discernable for experienced neuropsychologists.     

Inference deficits in right brain-damaged patients

The inferential reasoning ability of right hemisphere-damaged (RHD) patients was tested by presenting pairs of sentences which were to be treated as single, integrated units. The two sentences treated together made one interpretation likely (a correct inference); one of the sentences in isolation encouraged a different interpretation (an incorrect inference). The position of the misleading sentence was systematically varied. Results showed that, in contrast to normal controls, RHD patients have more trouble answering inference questions, especially those concerning incorrect inferences, than answering questions about the factual content of the passages. Also, RHD patients made significantly more errors when the misleading information was contained in the first rather than in the second sentence; this finding indicates that these patients have difficulty revising previously acquired knowledge in light of new information. These results suggest the impairment of several components of normal discourse processing subsequent to right hemisphere brain damage.     

Semantic disorders of auditory language comprehension in right brain-damaged patients

A test of auditory language comprehension was given to 110 right brain-damaged patients and to 94 normal controls in order to check if patients with lesions of the right (nondominant) hemisphere make a significantly higher number of semantic errors than normals. Confirmation of the hypothesis was obtained, but the relationship between semantic errors and lesion of the right hemisphere did not seem a simple and direct one. In fact, most of the lexical-semantic errors were due to associated variables (such as unilateral spatial agnosia and general mental deterioration) and not to the lesion of the right hemisphere per se. These data do not suggest a specific semantic capacity of the nondominant hemisphere but rather stress the fragility of the lexical-semantic organization at the cortical level.This work was assisted by a grant from C.N.R. (Consiglio Nazionale delle Ricerche).     

Comprehension of humorous and nonhumorous materials by left and right brain-damaged patients

Right hemisphere-damaged (RHD) and left hemisphere-damaged (LHD) aphasic patients were tested on a nonverbal cartoon completion task that included a humorous (Joke) and a nonhumorous (Story) condition. In both conditions, RHD patients performed worse than LHD patients. More importantly, the qualitative difference between the errors produced by the two groups suggests that right and left hemisphere brain damage impairs different components of narrative ability. RHD patients showed a preserved sensitivity to the surprise element of humor, and a diminished ability to establish coherence. Conversely, LHD patients, when they erred, showed an impaired sensitivity to the surprise element of humor, and a preserved ability to establish coherence by integrating content across parts of a narrative. These results suggest that the observed humor comprehension deficits of RHD patients result specifically from right hemisphere disease and not from brain damage irrespective of locus. The performances of the RHD and LHD patients groups together support a separation of narrative ability from the traditional aspects of language ability typically disrupted in aphasia.     

Poor hand-pointing to sounds in right brain-damaged patients: Not just a problem of spatial-hearing

We asked 22 right brain-damaged (RBD) patients and 11 elderly healthy controls to perform hand-pointing movements to free-field unseen sounds, while modulating two non-auditory variables: the initial position of the responding hand (left, centre or right) and the presence or absence of task-irrelevant ambient vision. RBD patients suffering from visual neglect, unlike RBD patients without neglect and healthy controls, showed a systematic rightward error in sound localisation, which was modulated by the non-auditory variables. Localisation errors were exacerbated by initial hand-position to the right of the body-midline, and reduced by the leftwards initial hand-position. Moreover, for the visual neglect patients, mere presence of ambient vision worsened localisation errors. These results demonstrate that although hand-pointing to sounds has often been considered a straightforward approach to investigate sound-localisation abilities in brain-damaged patients, in some patients it may actually reveal localisation deficits that reflect a combination of impaired spatial-hearing and spatial biases from other sensory modalities (i.e., vision and proprioception).     

Poor hand-pointing to sounds in right brain-damaged patients: not just a problem of spatial-hearing

We asked 22 right brain-damaged (RBD) patients and 11 elderly healthy controls to perform hand-pointing movements to free-field unseen sounds, while modulating two non-auditory variables: the initial position of the responding hand (left, centre or right) and the presence or absence of task-irrelevant ambient vision. RBD patients suffering from visual neglect, unlike RBD patients without neglect and healthy controls, showed a systematic rightward error in sound localisation, which was modulated by the non-auditory variables. Localisation errors were exacerbated by initial hand-position to the right of the body-midline, and reduced by the leftwards initial hand-position. Moreover, for the visual neglect patients, mere presence of ambient vision worsened localisation errors. These results demonstrate that although hand-pointing to sounds has often been considered a straightforward approach to investigate sound-localisation abilities in brain-damaged patients, in some patients it may actually reveal localisation deficits that reflect a combination of impaired spatial-hearing and spatial biases from other sensory modalities (i.e., vision and proprioception).     

The use of pronoun anaphora and speaker mood in the interpretation of conversational utterances by right hemisphere brain-damaged patients.

Understanding utterances in conversations requires a listener to weigh the disparate pieces of information present in a discourse. In this study, we examined how right hemisphere brain-damaged (RHD) patients and non-brain-damaged control subjects interpreted responses to questions concerning the location of a person (e.g., "Where's Dad?"). Stimulus vignettes included variation on three factors relevant to discourse comprehension: the mood of a speaker, the plausibility of the answer to a question, and whether the answer contained an anaphoric pronoun linking the response to the preceding question. Relative to the control subjects, the RHD patients made greater than normal use of the presence/absence of an anaphoric pronoun in their utterance interpretations, less than normal use of the speaker's mood, and marginally less than normal use of a response's plausibility. These data show how RHD patients rely on their largely intact linguistic abilities when understanding discourse and how their comprehension goes awry due to their reduced appreciation of other essential aspects of natural communication. The discussion focuses on the variable roles of speaker mood, plausibility, and pronoun anaphora in supporting inferences about a speaker's intended meaning and on the selective nature of RHD patients' impairment in this domain.     

Stimulus categorization by brain-damaged patients

Patients with localized insult to the right hemisphere, or to either the anterior or the posterior portion of the left hemisphere, as well as neurologically intact controls, evaluated stimuli on a seven-point rating scale for their degree of category membership. The stimuli were taken from one of two continua, one composed of fruit and vegetable items, and the other of items differing in hue and shape. Different subsets of stimuli provided different contexts for the judgments of category membership. The two left-hemisphere groups showed anomalies in categorizing the fruit and vegetable items but not the perceptual items, while the reverse was true for the right-hemisphere patients. Moreover, both left-hemisphere groups demonstrated context effects in their judgments of the representativeness of the fruit and vegetable items, but differed in the way in which they responded to changing contexts. Left posterior patients demonstrated weak category boundaries and even reclassified items. In contrast, patients with left anterior damage showed highly categorical responses and less differentiation of items within a category. All groups showed striking context effects in judgments of perceptual items in terms of changes in representativeness ratings and the location of a category boundary. Alternative interpretations of the results are offered.     

Appreciation of pragmatic interpretations of indirect commands: comparison of right and left hemisphere brain-damaged patients

Indirect commands can elicit "literal" interpretations, directly reflecting the content and form of the utterance, or "pragmatic" interpretations, incorporating knowledge of paralinguistic, social, or historical cues. The aim of this study was to demonstrate how right brain-damaged (RBD) subjects would perform on judgments of these forms of communication. It was predicted that relative to normal controls or aphasic subjects, the RBD subjects would have significant difficulty appreciating the pragmatic interpretation relative to the literal one. Subjects judged the appropriateness of two-part exchanges consisting of indirect commands, direct commands, Wh-questions coupled with pragmatic responses, literal responses, responses verifying the physical surround, or syntactically similar responses. The results confirm that the RBD subjects had a selective difficulty appreciating the indirect commands. Their preference of literal over pragmatic interpretations was significantly different to that of aphasics or normal controls. Hypotheses are offered to explain these data.     

Impaired pitch production and preserved rhythm production in a right brain-damaged patient with amusia

Pre- and postmorbid singing of a patient with amusia due to a right-hemispheric infarction was analyzed acoustically. This particular patient had a premorbid tape recording of her own singing without accompaniment. Appropriateness of pitch interval and rhythm was evaluated based on ratios of pitch and duration between neighboring notes. The results showed that melodic contours and rhythm were preserved but individual pitch intervals were conspicuously distorted. Our results support a hypothesis that pitch and rhythm are subserved by independent neural subsystems. We concluded that action-related acoustic information for controlling pitch intervals is stored in the right hemisphere.     

The analysis of drawing from memory performance in brain-damaged patients

The drawing from memory task is frequently used in cognitive neuropsychology to investigate visual processing impairments. However, in surprising contrast to most other neuropsychological tests, the analyses of results on this task are most often based solely on qualitative judgements about the normality of a patient's performance. In most case reports, these judgements are not made with reference to normative data and are not made by individuals who are impartial with respect to the study (that is, using a blind rating procedure). There are several grounds for arguing that such analyses are inadequate. First, seemingly abnormal drawings made by a patient may well be within the range of performance shown by control subjects. Second, judgments that are not based on a blind rating procedure are likely to be influenced by knowledge about the patient's performance on other tasks. We describe an alternative assessment procedure that addresses both of these concerns.     

Language ability in right and left hemiplegic children

The language abilities of three right and three left hemiplegic children between 6 and 8 years of age were compared. All children presented pre- or perinatally acquired unilateral lesions confirmed by CT scan, normal hearing, comparable performance I.Q.'s, and were being educated in regular classrooms. Right hemiplegic children were found to be inferior to the left hemiplegics on tasks of speech production, vocabulary comprehension, and syntactic comprehension and formulation. Right hemiplegics also acquired single words and two-word combinations later than did left hemiplegics.     

产权安排是社会道德的基础

作为社会经济生活中的一种根本制度安排和人们的一种基本权利,产权是社会道德的基础。一定的利益差别和产权界定,是道德产生的前提;社会产权制度的性质和变迁,规定着社会道德体系的特质和演变;社会产权安排的结构和状况,影响和制约着人们的道德行为选择和社会道德风尚。健全的产权安排有利于规范和约束人们的行为选择,安定人们的生活心态,创造积极的道德环境和条件,从而优化人们的道德行为选择,促进良好社会道德秩序的形成。     

Sensitivity to sub-syllabic constituents in brain-damaged patients: evidence from word games

Two experiments were conducted to examine whether left- (LHD) and right-hemisphere-damaged (RHD) patients exhibit sensitivity to sub-syllabic constituents (i.e., onsets and codas) in the generation of nonwords, using a word games paradigm adapted from. Four groups of individuals (including LHD fluent and nonfluent aphasic patients, RHD patients and normal controls) were trained to add syllables to monosyllabic CVC nonwords either after the initial consonant (Experiment 1) or prior to the final consonant (Experiment 2) to create bisyllabic nonwords. Experimental stimuli consisting of CCVC or CVCC nonwords tested whether participants would preserve or split the onset and coda constituents in producing the novel bisyllabic nonwords. Results revealed that the majority of subjects demonstrated sensitivity to the sub-syllabic constituents, preserving the onsets and codas. The fluent aphasic patients exhibited a greater than normal tendency to split the onset and coda constituents; however, the small number of individuals in that group whose data met inclusion criteria limits the conclusions that may be drawn from these findings. The results are discussed in relation to theories of phonological deficits in aphasia.