Extra-powerful on the visuo-perceptual space, but variable on the number space: Different effects of optokinetic stimulation in neglect patients

We studied the effects of optokinetic stimulation (OKS; leftward, rightward, control) on the visuo-perceptual and number space, in the same sample, during line bisection and mental number interval bisection tasks. To this end, we tested six patients with right-hemisphere damage and neglect, six patients with right-hemisphere damage but without neglect, and six neurologically healthy participants. In patients with neglect, we found a strong effect of leftward OKS on line bisection, but not on mental number interval bisection. We suggest that OKS influences the number space only under specific conditions

Comprehension and Egocentrism with Right Hemisphere Damage

Egocentrism is commonly reported after right brain damage (RHD), and can be apparent in discourse production. The purpose of this study was to examine whether discourse comprehension in adults with RHD may be similarly affected by egocentrism. The hypothesis was adults with RHD will interpret stories in light of personal preferences at the expense of contextual cues. Data from seven adults without brain damage and nine RHD participants indicated that negative, but not positive, character biases influenced comprehension for both groups. No significant group differences were obtained. Results are interpreted in light of the mildly-impaired RHD group

Rhythm in the speech of a person with right hemisphere damage: Applying the pairwise variability index

Although several aspects of prosody have been studied in speakers with right hemisphere damage (RHD), rhythm remains largely uninvestigated. This study compares the rhythm of an Australian English speaker with right hemisphere damage (due to a stroke, but with no concomitant dysarthria) to that of a neurologically unimpaired individual. The speakers' rhythm is compared using the pairwise variability index (PVI) which allows for an acoustic characterization of rhythm by comparing the duration of successive vocalic and intervocalic intervals. A sample of speech from a structured interview between a speech and language therapist and each participant was analysed. Previous research has shown that speakers with RHD may have difficulties with intonation production, and therefore it was hypothesized that there may also be rhythmic disturbance. Results show that the neurologically normal control uses a similar rhythm to that reported for British English (there are no previous studies available for Australian English), whilst the speaker with RHD produces speech with a less strongly stress-timed rhythm. This finding was statistically significant for the intervocalic intervals measured (t(8) = 4.7, p < .01), and suggests that some aspects of prosody may be right lateralized for this speaker. The findings are discussed in relation to previous findings of dysprosody in RHD populations, and in relation to syllable-timed speech of people with other neurological conditions

Training theory of mind following right hemisphere damage: A pilot study

Successful communicative interactions in large part rely on an ability to infer the mental states of conversational partners. Understanding other people’s mental states, such as thoughts, beliefs, and emotions, allows us to understand and predict their behaviors. Mental states are often described in terms of two components of a “Theory of Mind” (ToM): first-order beliefs, that is, what a person believes about the world, and the more complex second-order beliefs, that is, what one person believes about the mental state of another person. Theory of Mind (ToM) deficits have been reported in individuals subsequent to RHD as well as in other populations such as autism and patients with prefrontal lesion (Baron-Cohen et al., 1985, Happe et al., 1999 and Stone et al., 1998). Theoretical accounts consider ToM in relation to, for example, executive function or empathy, or as a relatively independent cognitive ability

Space-related confabulations after right hemisphere damage

Confabulations are usually referred to memory distortions, characterized by the production of verbal statements or actions that are inconsistent with the patient’s history and present situation. However, behavioral patterns reminiscent of memory confabulations can also occur in patients with right hemisphere damage, in relation to their personal, peripersonal or extrapersonal space. Thus, such patients may be unaware of their left hemiplegia and confabulate about it (anosognosia), deny the ownership of their left limbs (somatoparaphrenia), insult and hit them (misoplegia), or experience a “third”, supernumerary left limb. Right brain-damaged patients can also sometimes confabulate about the left, neglected part of images presented in their peripersonal space, or believe to be in another place (reduplicative paramnesia). We review here these instances of confabulation occurring after right hemisphere damage, and propose that they might reflect, at least partially, the attempts of the left hemisphere to make sense of inappropriate input received from the damaged right hemisphere

Horizontal visual search in a large field by patients with unilateral spatial neglect

In this study, we investigated the horizontal visual search ability and pattern of horizontal visual search in a large space performed by patients with unilateral spatial neglect (USN). Subjects included nine patients with right hemisphere damage caused by cerebrovascular disease showing left USN, nine patients with right hemisphere damage but no USN, and six healthy individuals with no history of brain damage who were age-matched to the groups with brain right hemisphere damage. The number of visual search tasks accomplished was recorded in the first experiment. Neck rotation angle was continuously measured during the task and quantitative data of the measurements were collected. There was a strong correlation between the number of visual search tasks accomplished and the total Behavioral Inattention Test Conventional Subtest (BITC) score in subjects with right hemisphere damage. In both USN and control groups, the head position during the visual search task showed a balanced bell-shaped distribution from the central point on the field to the left and right sides. Our results indicate that compensatory strategies, including cervical rotation, may improve visual search capability and achieve balance on the neglected side. © 2012 Elsevier Ltd. All rights reserved.Thesis of Ken Nakatani / 中谷 謙 博士論文 金沢大学医薬保健学総合研究科（保健学専攻

Pragmatic disorders and their social impact

Pragmatic disorders in children and adults have been the focus of clinical investigations for approximately 40 years. In that time, clinicians and researchers have established a diverse range of pragmatic phenomena that are disrupted in these disorders. Pragmatic deficits include problems with the use and understanding of speech acts, the processing of non-literal language, failure to adhere to Gricean maxims in conversation and discourse deficits. These deficits are found in several clinical populations including individuals with autistic spectrum disorders, schizophrenia, traumatic brain injury and right-hemisphere damage. However, what is less often investigated is the social impact of pragmatic disorders on the children and adults who are affected by them. In this paper, I examine what is known about pragmatic disorders in these clinical groups. I then consider the wider social consequences of these disorders, where consequences are broadly construed to include factors that act as indicators of social adjustment

Right hemisphere damage: Communication processing in adults evaluated by

Abstract -Right-brain-damaged individuals may present discursive, pragmatic, lexical-semantic and/or prosodic disorders. Objective: To verify the effect of right hemisphere damage on communication processing evaluated by the Brazilian version of the Protocole Montréal d&apos;Évaluation de la Communication (Montreal Communication Evaluation Battery) -Bateria Montreal de Avaliação da Comunicação, Bateria MAC, in Portuguese. Methods: A clinical group of 29 right-brain-damaged participants and a control group of 58 non-brain-damaged adults formed the sample. A questionnaire on sociocultural and health aspects, together with the Brazilian MAC Battery was administered. Results: Signifi cant differences between the clinical and control groups were observed in the following MAC Battery tasks: conversational discourse, unconstrained, semantic and orthographic verbal fl uency, linguistic prosody repetition, emotional prosody comprehension, repetition and production. Moreover, the clinical group was less homogeneous than the control group. Conclusions: A right-brain-damage effect was identifi ed directly, on three communication processes: discursive, lexical-semantic and prosodic processes, and indirectly, on pragmatic process. Key words: neuropsychology, right hemisphere, brain damage, communication. Lesão de hemisfério direito: processamento comunicativo em adultos avaliados pela versão brasileira do Protocole MEC -Bateria MAC Resumo -Os indivíduos com lesão vascular de hemisfério direito podem apresentar distúrbios discursivos, pragmáticos, léxico-semânticos e/ou prosódicos. Objetivo: Verifi car o efeito da lesão de hemisfério direito no processamento comunicativo avaliado pela versão Brasileira do Protocole Montréal d&apos;Évaluation de la Communication -Bateria Montreal de Avaliação da Comunicação, Bateria MAC (em português). Métodos: Participaram do estudo um grupo clínico, com 29 adultos lesados de hemisfério direito, e um grupo controle, com 58 adultos sem lesão neurológica. Foram administrados um questionário de dados socioculturais e aspectos da saúde e a Bateria MAC. Resultados: Houve diferenças signifi cativas entre os grupos clínico e controle nas tarefas da Bateria MAC discurso conversacional, evocação lexical livre, com critério ortográfi co e semântico, prosódia lingüísti-ca repetição, prosódia emocional compreensão, repetição e produção. Além disso, o grupo clínico mostrou-se menos homogêneo do que o controle. Conclusões: Identifi cou-se o efeito da lesão de hemisfério direito em três processamentos comunicativos: discursivo, léxico-semântico e prosódico e, indiretamente, no processamento pragmático. Palavras-chave: neuropsicologia, hemisfério direito, lesão cerebral, comunicação

Automated Analysis of Language Production in Aphasia and Right Hemisphere Damage: Frequency and Collocation Strength

BACKGROUND: Reliance on formulaic language, i.e., holistically processed multiword chunks, is claimed to distinguish speakers with aphasia, speakers with right-hemisphere damage (RHD), and neurotypical controls (NC). Frequency and collocation strength of word combinations are indicators of formulaic language. AIMS: We aimed to determine frequency and collocation properties of spoken production, as indicators of formulaic language, in people with aphasia, speakers with RHD and NC. METHODS AND PROCEDURES: We used computerized methods to investigate spontaneous language in 40 speakers: 10 with fluent aphasia (fA), 10 with non-fluent aphasia (nfA), 10 with RHD, and 10 NC. Our analysis not only focused on frequency and collocation strength of grammatical combinations as markers of formulaic language (using the British National Corpus as reference), but also looked at word frequency, language fluency, proportion of content words, and measures of lexical and combinatorial diversity. OUTCOME AND RESULTS: Both groups with aphasia differed from neurotypical speakers with regard to lexical features and word combinations. Their language was less fluent, less diverse at the word level, and, in the non-fluent group, contained a higher proportion of content words. Each aphasic group also differed significantly from controls with increased values on at least one marker of formulaic language. Speakers with RHD produced less-frequent combinations, which were more weakly collocated; however, these effects did not reach statistical significance. Conclusions: Our results show that formulaic language use distinguishes aphasic from other speakers and that differences can be tracked with an automated, corpus-based script that uses frequency and collocation variables. We present our study in the context of usage-based frameworks of language