Brain-damaged Adults Research Articles

Some Conceptual and Empirical Shortcomings of IIT

The Integrated Information Theory of consciousness (IIT) has generated much excitement inside and outside the scientific community, and seems to many the leading contender for a satisfactory theory grounded in systems neuroscience. It is a bold theory, one that provides plausible explanations for various recognized neuroscientific facts, makes surprising predictions that go beyond current scientific orthodoxy but are potentially testable, and has inspired development of what appears to be an effective technique for detecting the presence of consciousness in organisms incapable of verbal report, such as non-human animals, neonates, and severely brain-damaged adults. Despite these virtues, IIT appears fundamentally flawed: This paper first revisits some key conceptual and technical issues that have been raised previously but remain unresolved—in particular, issues concerning IIT’s concept of “information” and its approach to the “hard problem”—and then focuses on several empirical phenomena that IIT seems unable to handle satisfactorily. These include: 1. cases of multiple personality or dissociative identity disorder in which complex and overlapping centers of consciousness co-occur in single human organisms; 2. the failure of the intense phenomenology of psychedelic states to be straightforwardly reflected in accompanying neuroelectric activity; and, most critically; 3. the occurrence of profound and personally transformative near-death experiences (NDEs) under extreme physiological conditions such as cardiac arrest, in which IIT predicts that no conscious experience whatsoever should be possible. These empirical arguments show that IIT itself is untenable, and they apply also to its physicalist competitors. Scientifically and philosophically respectable alternatives, however, are available.

Hemispheric Organization for Visual Object Recognition: A Theoretical Account and Empirical Evidence.

Despite the similarity in structure, the hemispheres of the human brain have somewhat different functions. A traditional view of hemispheric organization asserts that there are independent and largely lateralized domain-specific regions in ventral occipitotemporal (VOTC), specialized for the recognition of distinct classes of objects. Here, we offer an alternative account of the organization of the hemispheres, with a specific focus on face and word recognition. This alternative account relies on three computational principles: distributed representations and knowledge, cooperation and competition between representations, and topography and proximity. The crux is that visual recognition results from a network of regions with graded functional specialization that is distributed across both hemispheres. Specifically, the claim is that face recognition, which is acquired relatively early in life, is processed by VOTC regions in both hemispheres. Once literacy is acquired, word recognition, which is co-lateralized with language areas, primarily engages the left VOTC and, consequently, face recognition is primarily, albeit not exclusively, mediated by the right VOTC. We review psychological and neural evidence from a range of studies conducted with normal and brain-damaged adults and children and consider findings which challenge this account. Last, we offer suggestions for future investigations whose findings may further refine this account.

The neuroscience of musical entrainment: insights from EEG frequency-tagging

Event Abstract Back to Event The neuroscience of musical entrainment: insights from EEG frequency-tagging Sylvie Nozaradan1* 1 Catholic University of Louvain, Belgium Music powerfully compels us to move to the musical rhythm, showcasing the remarkable ability of humans to perceive and produce rhythmic inputs. There is a wave of current research exploring the neural bases of this rhythmic entrainment in both human and non-human animals, in evolutionary terms and in development. One way to investigate these neural dynamics is frequency-tagging, an approach recently developed to capture the neural processing of musical rhythm with surface or intracerebral electroencephalography (EEG). Recent experiments conducted in healthy and brain-damaged adults, and also in infants, while exposed to simplified rhythmic patterns or naturalistic music will be presented. Results show that, although the auditory system presents a remarkable ability to synchronize to the rhythmic input, neural populations shape the rhythmic input by amplifying specific frequencies. This selective enhancement seems to correlate with perception and individual ability to move in time with musical rhythm. These different results may lead to a new understanding of the neural bases of rhythmic entrainment. Keywords: electroecephalography, Rhythm perception and production, frequency-tagging, neural synchronization, music cognition Conference: 13th National Congress of the Belgian Society for Neuroscience , Brussels, Belgium, 24 May - 24 May, 2019. Presentation Type: Platform presentation Topic: Behavioral/Systems Neuroscience Citation: Nozaradan S (2019). The neuroscience of musical entrainment: insights from EEG frequency-tagging. Front. Neurosci. Conference Abstract: 13th National Congress of the Belgian Society for Neuroscience . doi: 10.3389/conf.fnins.2019.96.00077 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 18 Apr 2019; Published Online: 27 Sep 2019. * Correspondence: Prof. Sylvie Nozaradan, Catholic University of Louvain, Louvain-la-Neuve, Belgium, sylvie.nozaradan@uclouvain.be Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Sylvie Nozaradan Google Sylvie Nozaradan Google Scholar Sylvie Nozaradan PubMed Sylvie Nozaradan Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

The picture morphing task – an efficient and quick means to measure updating

We report the results of three studies using a picture morphing task. We argue that this task is an effective, easy to administer, and widely applicable assessment tool for probing the ability to update perceptual representations. By presenting a series of fifteen images that morph from one unambiguous object (e.g., rabbit) to a completely different object (e.g., duck), we can assess the time and evidence necessary for perceptual re-categorization in children, brain-damaged adults, and normal adult controls. Study one presented 3 and 5 year old children with a version of the picture morphing task and a Theory of Mind assessment (i.e., False Belief Task). The picture morphing task could be performed by both age groups. Within the 5-year old group, children who passed a False Belief Task and were able to correctly explain why, showed faster perceptual updating. Study two demonstrated that damage to the right hemisphere – especially the right anterior insula – resulted in an updating impairment; these patients requiring significantly more pictures before they reported the new object compared to left brain damaged patients. In study three, an fMRI experiment with healthy individuals, the anterior insula and mid-frontal regions were activated at the time when a change was reported, and immediately before. In summary, the picture morphing task offers an an efficient tool for measuring updating mental representations in vastly different experimental settings and participant populations. Meeting abstract presented at VSS 2016

An alternative to domain-general or domain-specific frameworks for theorizing about human evolution and ontogenesis.

This paper maintains that neither a domain-general nor a domain-specific framework is appropriate for furthering our understanding of human evolution and ontogenesis. Rather, as we learn increasingly more about the dynamics of gene-environment interaction and gene expression, theorists should consider a third alternative: a domain-relevant approach, which argues that the infant brain comes equipped with biases that are relevant to, but not initially specific to, processing different kinds of input. The hypothesis developed here is that domain-specific core knowledge/specialized functions do not constitute the start state; rather, functional specialization emerges progressively through neuronal competition over developmental time. Thus, the existence of category-specific deficits in brain-damaged adults cannot be used to bolster claims that category-specific or domain-specific modules underpin early development, because neural specificity in the adult brain is likely to have been the emergent property over time of a developing, self-structuring system in interaction with the environment.

Modality differences between written and spoken story retelling in healthy older adults

Modality differences between written and spoken story retelling in healthy older adults

Self-face and self-body recognition in autism

The advantage in responding to self vs. others’ body and face-parts (the so called self-advantage) is considered to reflect the implicit access to the bodily self representation and has been studied in healthy and brain-damaged adults in previous studies. If the distinction of the self from others is a key aspect of social behaviour and is a precursory ability of later conceptual self development, it is interesting to investigate these functions in children with autism spectrum disorder (ASD). Here we investigate the implicit access to self representation in children with autism spectrum disorder (ASD) and in children with typical development (TD). Children with ASD were submitted to a visual matching-to-sample task with stimuli depicting their own or other people's body or face-parts. Participants were required to decide which of the two vertically aligned images matched the central target stimulus. The performance of children with ASD was compared to the performance of children with typical development (TD). Children with ASD were less accurate compared to children with typical development. Interestingly, children with ASD performed the task better when they visually matched their own, compared to others’ stimuli showing the self-advantage effect, as well as children with TD.

Virtual navigation for memory rehabilitation in a traumatic brain injured patient

The use of 3D video games in memory rehabilitation has been explored very little. A virtual navigation task allows participants to encode the spatial layout of the virtual environment and activate areas involved in memory processing. We describe the rehabilitation of a 24-year-old man with traumatic brain injury presenting memory deficits, and evaluate the efficacy of a navigational training program measuring neuropsychological changes and fMRI modification cerebral activations. Memory improvement appears to be present both after navigational training and in follow-up testing. Furthermore, fMRI data suggest that this training may increase activation of the hippocampal and parahippocampal brain regions. The results suggest that intensive training in virtual navigational tasks may result in an enhancement of memory function in brain-damaged adults.

Perceptual cues used by listeners to discriminate fluent from nonfluent narrative discourse

Background: Language fluency is a common diagnostic marker for discriminating among aphasia subtypes and improving clinical inference about site of lesion. Nevertheless, fluency remains a subjective construct that is vulnerable to a number of potential sources of variability, both between and within raters. Moreover, this variability is compounded by distinct neurological aetiologies that shape the characteristics of a narrative speech sample. Previous research on fluency has focused on characteristics of a particular patient population. Less is known about the ways that raters spontaneously weigh different perceptual cues when listening to narrative speech samples derived from a heterogeneous sample of brain-damaged adults. Aim: We examined the weighted contribution of a series of perceptual predictors that influence listeners' judgements of language fluency among a diverse sample of speakers. Our goal was to sample a range of narrative speech representing most fluent (i.e., healthy controls) to potentially least nonfluent (i.e., left inferior frontal lobe stroke). Methods & Procedures: Three raters blind to patient diagnosis made forced choice judgements of fluency (i.e., fluent or nonfluent) for 61 pseudorandomly presented narrative speech samples elicited by the BDAE Cookie Theft picture. Samples were collected from a range of clinical populations, including patients with frontal and temporal lobe pathologies and non-brain-damaged speakers. We conducted a logistic regression analysis in which the dependent measure was the majority judgement of fluency for each speech sample (i.e., fluent or non-fluent). The statistical model contained five predictors: speech rate, syllable type token ratio, speech productivity, audible struggle, and filler ratio. Outcomes & Results: This statistical model fit the data well, discriminating group membership (i.e., fluent or nonfluent) with 95.1% accuracy. The best step of the regression model included the following predictors: speech rate, speech productivity, and audible struggle. Listeners were sensitive to different weightings of these predictors. Conclusions: A small combination of perceptual variables can strongly discriminate whether a listener will assign a judgement of fluent versus nonfluent. We discuss implications for these findings and identify areas of potential future research towards further specifying the construct of fluency among adults with acquired speech and language disorders.

Relationships between number and space processing in adults with and without dyscalculia

A large body of evidence indicates clear relationships between number and space processing in healthy and brain-damaged adults, as well as in children. The present paper addressed this issue regarding atypical math development. Adults with a diagnosis of dyscalculia (DYS) during childhood were compared to adults with average or high abilities in mathematics across two bisection tasks. Participants were presented with Arabic number triplets and had to judge either the number magnitude or the spatial location of the middle number relative to the two outer numbers. For the numerical judgment, adults with DYS were slower than both groups of control peers. They were also more strongly affected by the factors related to number magnitude such as the range of the triplets or the distance between the middle number and the real arithmetical mean. By contrast, adults with DYS were as accurate and fast as adults who never experienced math disability when they had to make a spatial judgment. Moreover, number–space congruency affected performance similarly in the three experimental groups. These findings support the hypothesis of a deficit of number magnitude representation in DYS with a relative preservation of some spatial mechanisms in DYS. Results are discussed in terms of direct and indirect number–space interactions.

〈言語学と言語障害学との接点〉成人脳損傷者の談話・会話データの分析

〈言語学と言語障害学との接点〉成人脳損傷者の談話・会話データの分析

Can Adolescents With Williams Syndrome Tell the Difference Between Lies and Jokes?

A group of adolescents with Williams syndrome (WS) was compared to matched groups of adolescents with Prader-Willi syndrome and nonspecific mental retardation on a task that tested the ability to distinguish different forms of nonliteral language. Participants listened to stories that ended in either a lie or an ironic joke. They were asked to decide the form of the nonliteral utterance and justify their responses. Almost none of the participants in any of the groups were able to correctly classify the ironic jokes, instead judging them to be lies because they did not correspond to reality. Their errors were similar to those made by younger normally developing children, but contrasted with those made by brain-damaged adults. These data are taken as further evidence that neurodevelopmental disorders are quite different from acquired brain disorders and require different neuropsychological models. The findings from this study also have important implications for considering the difficulties that adolescents with WS and other disorders will have in everyday social situations, especially among peers.

Affective communication in normal and brain-damaged adults: an overview.

In the past few decades an increasing number of investigators have examined how emotions are communicated through facial expression, speech prosody, and language in nonclinical and brain-damaged populations. Disorders of emotional communication (often referred to as affective processing disorders) are commonly associated with brain damage. These disorders include difficulty with expressing and perceiving emotional information, regulating emotions in communicative interactions, and demonstrating sensitivity to the emotional expressions of communicative partners. The purposes of this article are to: (1) describe "normal" affective communication; (2) review disorders in affective expression, perception, and regulation; (3) discuss the modality of facial expression and disorders of affective facial expression; and (4) present some informal tools for assessing affective processing.

Contributions of Phonological and Semantic Short-Term Memory to Sentence Processing: Evidence from Two Cases of Closed Head Injury in Children

This paper reports the short-term memory and sentence processing performance of two head-injured children who were approximately 10 years of age at the time of test. The two children were found to have similarly reduced memory span on a variety of short-term memory tasks relative to age-matched control children, but differing patterns of performance. One child showed reduced (or absent) effects of phonological variables, and the other showed reduced effects of semantic variables. A dissociation in their performance on sentence processing tasks was also observed, with one child showing preserved comprehension but impaired repetition, and the other child showing the reverse. The results are consistent with previous findings from brain-damaged adults supporting a multiple-components model of short-term memory in which phonological and semantic components play different roles in sentence processing. Contrary to our initial hypothesis, the phonological component did not appear to play a more important role in sentence comprehension for children than for adults.

Suppression and discourse comprehension in right brain-damaged adults: A preliminary report

Eighteen right-hemisphere-damaged (RHD) and 15 control subjects listened to sentences that ended in lexical ambiguities. The sentence verbs biased ambiguity interpretation. Probe words, representing unbiased meanings of the ambiguities, were presented for rapid judgements of their fit with the sentences. In rejecting probe words, both groups showed interference from unbiased meanings of the ambiguities at a short (175 ms) probe interval. Only RHD adults demonstrated interference 1000 ms after sentence offset, indicating that they suppressed contextually inappropriate meanings less effectively than control subjects. Discourse comprehension performance in RHD adults was also correlated with suppression. Theoretical and clinical implications are considered.

The Ability to Perceive and Comprehend Intonation in Linguistic and Affective Contexts by Brain-Damaged Adults

Receptive tasks of linguistic and affective prosody were administered to 9 right-hemisphere-damaged (RHD), 10 left-hemisphere-damaged (LHD), and 10 age-matched control (NC) subjects. Two tasks measured subjects' ability to discriminate utterances based solely on prosodic cues, and six tasks required subjects to identify linguistic or affective intonational meanings. Identification tasks manipulated the degree to which the auditory stimuli were structured linguistically, presenting speech-filtered, nonsensical, and semantically well-formed utterances in different tasks. Neither patient group was impaired relative to normals in discriminating prosodic patterns or recognizing affective tone conveyed suprasegmentally, suggesting that neither the LHD nor the RHD patients displayed a receptive disturbance for emotional prosody. The LHD group, however, was differentially impaired on linguistic rather than emotional tasks and performed significantly worse than the NC group on linguistic tasks even when semantic information biased the target response.

Tonal Coarticulation in Thai after Unilateral Brain Damage

The magnitude and temporal extent of anticipatory and perseverative tonal coarticulation was investigated in Thai-speaking normal and brain-damaged adults. A total of 47 speakers (10 young normal, 10 old normal, 13 nonaphasic right-brain-damaged patients, 14 left-brain-damaged aphasic patients, 9 fluent, 5 nonfluent) produced all 25 possible sequences of two tones from the five lexical tones of Thai embedded in a carrier sentence.F0contours were analyzed in terms of height and slope at 10% intervals throughout the duration of the two syllables. Acoustic analysis revealed that anticipatory and perseverative tonal coarticulation of tones was markedly reduced in left fluent aphasics, totally absent in left nonfluent aphasics, but reasonably intact in right hemisphere patients. Findings are interpreted to highlight the nature of speech disturbances in nonfluent and fluent aphasia, hemispheric specialization for tone, and tonal coarticulation in Thai.

Can WISC-R IQ values be computed validly for learning-disabled children?

Prior research demonstrated that the relationships between age and neuropsychological test scores are much weaker in brain-damaged adults and children than in non-brain-damaged subjects It appears that the effects of brain damage on test scores are sufficiently strong to diminish the influence of age and education Similar results have been found with learning-disabled children The present study evaluated the effect of age adjustments on WISC-R IQ values and subtest scores The results suggest that conventional scoring of the WISC-R, which requires an age adjustment to obtain the IQ, underestimates the IQs especially of older LD children, apparently reflecting the learning-disabled child's limited rate of acquisition of intellectual abilities with advancing age.

Inferential abilities of normal and right hemisphere damaged adults

There were two aims of this study. The first was to compare indirect inferencing abilities by nine right hemisphere brain-damaged (RHD) adults with 18 matched normal controls. The second purpose was to determine the best condition in which to present information to the RHD individuals for the purpose of forming these inferences. Three conditions were evaluated: (1) Auditory-Only, (2) Orthographic-Only, and (3) Combined Auditory/Orthographic. It was hypothesized that right hemisphere damaged persons would perform most successfully when the materials (narrative paragraphs) were presented using the combined condition. Both groups performed significantly better in the combined Auditory/Orthographic condition. There were no significant differences in the performances of the RHD group as compared to the normal controls. This suggested that the RHD group did not exhibit an inference impairment on this type of linguistic task.

Calculation and number processing: assessment battery; role of demographic factors.

This paper describes the structure and contents of EC301, a standardized testing battery for the evaluation of brain-damaged adults in the area of calculation and number processing. The battery was administered to 180 normal subjects stratified by education (3 levels), age (3) and gender. EC301 is composed of a large variety of tasks dealing with basic arithmetic skills, and their linguistic, spatial, and mnesic dimensions. The three main notational systems for numbers--Arabic digits, written verbal, and spoken verbal number forms--are explored. Analysis of error rates indicated the effect of some demographic factors (principally, education; incidentally, gender) on normal performance in some tasks.