Effects of right and left hemisphere damage on performance of the "Right Hemisphere Communication Battery"

A Hebrew adaptation of Gardner and Brownell's (1986) "Right Hemisphere Communication Battery" (HRHCB) was administered to 27 right brain-damaged (RBD) patients, 31 left brain-damaged (LBD) patients, and 21 age-matched normal controls. Both patient groups showed deficits relative to controls and overall there was no difference between the two patient groups. A factor analysis of patients' scores on the HRHCB yielded two interpretable factors, a verbal and a nonverbal one. These factors were not lateralized. Performance of patients on the HRHCB correlated significantly and positively with performance on most tests of basic language functions, measured with a Hebrew adaptation of the "Western Aphasia Battery" (HWAB) and with other cognitive functions measured with standardized neuropsychological tests. There were stronger correlations of HRHCB with subtests of the HWAB in LBD patients and with nonlanguage cognitive tests in RBD patients. In the LBD group, HRHCB subtests' scores correlated negatively with lesion extent in frontal and temporal perisylvian regions. Such localization was not observed in RBD patients. The results argue against selective right hemisphere (RH) involvement in the RHCB, alleged to measure pragmatic aspects of language use, and show, instead, bilateral involvement. The results also argue against a modular organization of these functions of language use, especially in the RH.     

Neuronal changes in normal human aging and Alzheimer's disease

This article discusses age-related changes in brain weight, total number of cortical neurons, cortical dendrites, spine, and synapse density. The conclusion is that the present outlook is less grim than it was 30 years ago. Age-related reduction appears to be specific to brain region and cortical layer rather than a general feature. In addition, we describe a different pattern of changes that occur in Alzheimer's disease patients. This review concludes that the association cortices in particular are affected in aging and Alzheimer's disease and that the primary visual and somatosensory cortices are relatively spared.     

From agape to organs: religious difference between Japan and America in judging the ethics of transplant

This essay argues that Japan's resistance to the practice of transplanting organs from persons deemed "brain dead" may not be the result, as some claim, of that society's religions being not yet sufficiently expressive of love and altruism. The violence to the body necessary for the excision of transplantable organs seems to have been made acceptable to American Christians at a unique historical "window of opportunity" for acceptance of that new form of medical technology. Traditional reserve about corpse mutilation had weakened and, especially as presented by the theologian Joseph Fletcher, organ donation was touted as both expressive of agape and a way of "updating" Christianity via the ethics of Utilitarianism. Many Japanese, largely Buddhist and Confucian in their orientation, view these changed valorizations as neither necessary nor patently more ethical than those of their own traditions.     

Traumatic Brain Injury as a Risk Factor for Alzheimer's Disease: A Review

Accumulating epidemiological evidence implicates traumatic brain injury as a pathogenic agent in the development of Alzheimer's disease (AD). Considering the increase in the prevalence of both traumatic brain injury and AD in recent times, the possibility that brain trauma may provoke the early development of AD has important implications for health service planning, preventative efforts, and medico-legal compensation settlements. This paper evaluates the plausibility of the proposed link between traumatic brain injury and AD, largely by way of exploring a theoretical perspective advanced by Satz (1993) and considering recent contributions from the epidemiological, neuropathological, and biochemical literature that are pertinent to this issue. The literature reviewed provides sufficient support and empirical vindication to give credence to the proposed association between these two neuropsychological entities at the statistical, theoretical, and biological level.     

Speech and non-speech processing in people with specific language impairment: a behavioural and electrophysiological study

McArthur and Bishop (2004) found that people with specific language impairment (SLI) up to 14 years of age have poor behavioural frequency discrimination (FD) thresholds for 25-ms pure tones, while people with SLI upto 20 years of age have abnormal auditory N1--P2--N2 event-related potential (ERP) responses to the same tones. In the present study, we extended these findings to more complex non-speech and speech sounds by comparing younger (around 13 years) and older (around 17 years) teenagers with SLI and controls for their behavioural FD thresholds and N1-P2 ERPs to 25 and 250-ms pure tones, vowels, and non-harmonic complex tones. We found that a subgroup of people with SLI had abnormal responses to tones and vowels at the level of behaviour and the brain, and that poor processing was associated with the spectral complexity of auditory stimuli rather than their phonetic significance. We suggest that both the age of listeners and the sensitivity of psychoacoustic tasks to age-related changes in auditory skills may be crucial factors in studies of sound processing in SLI.     

Weak coherence,no theory of mind,or executive dysfunction? Solving the puzzle of pragmatic language disorders

Deficits in pragmatic language ability are common to a number of clinical populations, for example, right-hemisphere damage (RHD), Autism and traumatic brain injury (TBI). In these individuals the basic structural components of language may be intact, but the ability to use language to engage socially is impaired. Despite the nature of these difficulties being well documented, exactly what causes these difficulties is less clear. Furthermore, the current status of causal explanations for pragmatic difficulties across these populations is divergent and sometimes contradictory. This paper explores the empirical validity of three theories that attempt to explain pragmatic language impairment. It is recommended that a new, more convergent approach to investigating the causes of pragmatic language disability be adopted.     

On matters of mind and body: regarding Descartes

In this paper the author considers Descartes’ place in current thinking about the mind‐body dilemma. The premise here is that in the history of ideas, the questions posed can be as significant as the answers acquired. Descartes’ paramount question was ‘How do we determine certainty?’ and his pursuit of an answer led to cogito ergo sum. His discovery simultaneously raised the question whether mind is separate from or unified with the body. Some who currently hold that brain and subjectivity are unified contend that the philosopher ‘split’ mind from body and refer to ‘Descartes’ error’. This paper puts forward that Descartes’ detractors fail to recognise Descartes’ contribution to Western thought, which was to introduce the Enlightenment and to give a place to human subjectivity. Added to this, evidence from Descartes’ correspondence with Princess Elisabeth of Bohemia supports the conclusion that Descartes did in fact believe in the unity of mind and body although he could not reconcile this rationally with the certainty from personal experience that they were separate substances. In this Descartes was engaged in just the same dilemma as that of current thinkers and researchers, a conflict which still is yet to be resolved.     

Sweet-cheeks vs. pea-brain: embodiment,valence, and task all influence the emotional salience of language

Previous research has found that more embodied insults (e.g. numbskull) are identified faster and more accurately than less embodied insults (e.g. idiot). The linguistic processing of embodied compliments has not been well explored. In the present study, participants completed two tasks where they identified insults and compliments, respectively. Half of the stimuli were more embodied than the other half. We examined the late positive potential (LPP) component of event-related potentials in early (400–500?ms), middle (500–600?ms), and late (600–700?ms) time windows. Increased embodiment resulted in improved response accuracy to compliments in both tasks, whereas it only improved accuracy for insults in the compliment detection task. More embodied stimuli elicited a larger LPP than less embodied stimuli in the early time window. Insults generated a larger LPP in the late time window in the insult task; compliments generated a larger LPP in the early window in the compliment task. These results indicate that electrophysiological correlates of emotional language perception are sensitive to both top-down and bottom-up processes.     

Found in Translation: Late Bilinguals Do Automatically Activate Their Native Language When They Are Not Using It

In their paper “Do Bilinguals Automatically Activate Their Native Language When They Are Not Using it?”, Costa, Pannunzi, Deco, and Pickering (Cognitive Science, 2017) proposed a reinterpretation of Thierry and Wu's (2004, 2007) finding of native language‐based (Chinese, L1) ERP effects when they tested Chinese–English late bilinguals exclusively in their second language (English, L2). Using simulations in a six‐node Hebbian learning model (three L1 nodes, three L2 nodes), Costa et al. suggested that form overlaps in L1 between otherwise unrelated words create a persistent relationship between their L2 translations. In this scenario, words in the nascent L2 lexicon overlapping in their L1 translations would become linked during learning because of the form overlap in L1; once the L2 words are learned, the direct link between them would be sufficient to generate robust, apparently “L1‐mediated” priming without requiring any activation of L1 translations. Costa et al. contend that links between L2 words remain beyond the learning phase, even after links to L1 representations have been severed, and thus that their model affords an alternative account to (but not a rebuttal of) Thierry and Wu's claim of language non‐selective activation—or automatic activation of translation equivalents—in late bilinguals. In this response, we build on Costa et al.'s original simulation code, showing that it can only reproduce L1‐independent priming when implementing the L1 disconnection in their particular way. By contrast, when severing inter‐language connections bidirectionally, their model fails to retain any sizeable influence of L1 form overlap on L2 activations. The model is not the theory, however, and we discuss several issues that would need to be addressed in further attempts to model language non‐selective activation in late bilinguals.     

Effects of speed of word processing on semantic access: the case of bilingualism

Bilingual speakers generally manifest slower word recognition than monolinguals. We investigated the consequences of the word processing speed on semantic access in bilinguals. The paradigm involved a stream of English words and pseudowords presented in succession at a constant rate. English-Welsh bilinguals and English monolinguals were asked to count the number of letters in pseudowords and actively disregard words. They were not explicitly told that pairs of words in immediate succession were embedded and could either be semantically related or not. We expected that slower word processing in bilinguals would result in semantic access indexed by semantic priming. As expected, bilinguals showed significant semantic priming, indexed by an N400 modulation, whilst monolinguals did not. Moreover, bilinguals were slower in performing the task. The results suggest that bilinguals cannot discriminate between pseudowords and words without accessing semantic information whereas monolinguals can dismiss English words on the basis of subsemantic information.