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Although the cerebellum contributes to higher-order cognitive and emotional functions relevant to posttraumatic stress disorder (PTSD), prior research on cerebellar volume in PTSD is scant, particularly when considering subregions that differentially map on to motor, cognitive, and affective functions. In a sample of 4215 adults (PTSD n = 1642; Control n = 2573) across 40 sites from the ENIGMA-PGC PTSD working group, we employed a new state-of-the-art deep-learning based approach for automatic cerebellar parcellation to obtain volumetric estimates for the total cerebellum and 28 subregions. Linear mixed effects models controlling for age, gender, intracranial volume, and site were used to compare cerebellum volumes in PTSD compared to healthy controls (88% trauma-exposed). PTSD was associated with significant grey and white matter reductions of the cerebellum. Compared to controls, people with PTSD demonstrated smaller total cerebellum volume, as well as reduced volume in subregions primarily within the posterior lobe (lobule VIIB, crus II), vermis (VI, VIII), flocculonodular lobe (lobule X), and corpus medullare (all p-FDR < 0.05). Effects of PTSD on volume were consistent, and generally more robust, when examining symptom severity rather than diagnostic status. These findings implicate regionally specific cerebellar volumetric differences in the pathophysiology of PTSD. The cerebellum appears to play an important role in higher-order cognitive and emotional processes, far beyond its historical association with vestibulomotor function. Further examination of the cerebellum in trauma-related psychopathology will help to clarify how cerebellar structure and function may disrupt cognitive and affective processes at the center of translational models for PTSD.

Although the cerebellum contributes to higher-order cognitive and emotional functions relevant to posttraumatic stress disorder (PTSD), prior research on cerebellar volume in PTSD is scant, particularly when considering subregions that differentially map on to motor, cognitive, and affective functions. In a sample of 4215 adults (PTSD n = 1642; Control n = 2573) across 40 sites from the ENIGMA-PGC PTSD working group, we employed a new state-of-the-art deep-learning based approach for automatic cerebellar parcellation to obtain volumetric estimates for the total cerebellum and 28 subregions. Linear mixed effects models controlling for age, gender, intracranial volume, and site were used to compare cerebellum volumes in PTSD compared to healthy controls (88% trauma-exposed). PTSD was associated with significant grey and white matter reductions of the cerebellum. Compared to controls, people with PTSD demonstrated smaller total cerebellum volume, as well as reduced volume in subregions primarily within the posterior lobe (lobule VIIB, crus II), vermis (VI, VIII), flocculonodular lobe (lobule X), and corpus medullare (all p -FDR < 0.05). Effects of PTSD on volume were consistent, and generally more robust, when examining symptom severity rather than diagnostic status. These findings implicate regionally specific cerebellar volumetric differences in the pathophysiology of PTSD. The cerebellum appears to play an important role in higher-order cognitive and emotional processes, far beyond its historical association with vestibulomotor function. Further examination of the cerebellum in trauma-related psychopathology will help to clarify how cerebellar structure and function may disrupt cognitive and affective processes at the center of translational models for PTSD.

Disease-specific mechanisms underlying emotion recognition difficulties in behavioural -variant frontotemporal dementia (bvFTD), Alzheimers disease (AD), and Parkinsons dis-ease (PD) are unknown. Interoceptive accuracy, accurately detecting internal cues (e.g., ones heart beating), and cognitive abilities are candidate mechanisms underlying emotion recognition.One hundred and sixty-eight participants (52 bvFTD; 41 AD; 24 PD; 51 controls) were recruited. Emotion recognition was measured via the Facial Affect Selection Task or the Mini-Social and Emotional Assessment Emotion Recognition Task. Interoception was assessed with a heartbeat detection task. Participants pressed a button each time they: 1) felt their heartbeat (Interoception); or 2) heard a recorded heartbeat (Exteroception-con-trol). Cognition was measured via the Addenbrookes Cognitive Examination-III or the Montreal Cognitive Assessment. Voxel-based morphometry analyses identified neural correlates associated with emotion recognition and interoceptive accuracy. All patient groups showed worse emotion recognition and cognition than controls (all Ps < .008). Only the bvFTD showed worse interoceptive accuracy than controls (P < .001). Regression analyses revealed that in bvFTD worse interoceptive accuracy predicted worse emotion recognition (P = .008). Whereas worse cognition predicted worse emotion recogni-tion overall (P < .001). Neuroimaging analyses revealed that the insula, orbitofrontal cortex, and amygdala were involved in emotion recognition and interoceptive accuracy in bvFTD. Here, we provide evidence for disease-specific mechanisms for emotion recognition difficulties. In bvFTD, emotion recognition impairment is driven by inaccurate perception of the internal milieu. Whereas, in AD and PD, cognitive impairment likely underlies emotion recognition deficits. The current study furthers our theoretical understanding of emotion and highlights the need for targeted interventions. (c, Funding Agencies|ForeFront; National Health and Medical Research Council (NHMRC) [GNT1037746]; Australian Research Council grant [DP170101815]; Takeda [CW2680521]; CONICET; FONCYT-PICT [2017-1818, 2017-1820]; ANID/FONDECYT [1,210,195, 1,210,176, 1,220,995]; ANID/FONDAP [15,150,012]; ANID/PIA/ANILLOS [ACT210096]; Multi-Partner Consortium to Expand Dementia Research in Latin America (ReDLat) - National Institutes of Aging of the National Institutes of Health [R01AG057234]; Alzheimers Association grant [SG-20-725707-ReDLat]; Rainwater Foundation; Global Brain Health Institute; NHMRC Senior Research Fellowship [GNT1103258]; NHMRC Career Development Fellowship [GNT1158762]

Disease-specific mechanisms underlying emotion recognition difficulties in behavioural -variant frontotemporal dementia (bvFTD), Alzheimers disease (AD), and Parkinsons dis-ease (PD) are unknown. Interoceptive accuracy, accurately detecting internal cues (e.g., ones heart beating), and cognitive abilities are candidate mechanisms underlying emotion recognition.One hundred and sixty-eight participants (52 bvFTD; 41 AD; 24 PD; 51 controls) were recruited. Emotion recognition was measured via the Facial Affect Selection Task or the Mini-Social and Emotional Assessment Emotion Recognition Task. Interoception was assessed with a heartbeat detection task. Participants pressed a button each time they: 1) felt their heartbeat (Interoception); or 2) heard a recorded heartbeat (Exteroception-con-trol). Cognition was measured via the Addenbrookes Cognitive Examination-III or the Montreal Cognitive Assessment. Voxel-based morphometry analyses identified neural correlates associated with emotion recognition and interoceptive accuracy. All patient groups showed worse emotion recognition and cognition than controls (all Ps < .008). Only the bvFTD showed worse interoceptive accuracy than controls (P < .001). Regression analyses revealed that in bvFTD worse interoceptive accuracy predicted worse emotion recognition (P = .008). Whereas worse cognition predicted worse emotion recogni-tion overall (P < .001). Neuroimaging analyses revealed that the insula, orbitofrontal cortex, and amygdala were involved in emotion recognition and interoceptive accuracy in bvFTD. Here, we provide evidence for disease-specific mechanisms for emotion recognition difficulties. In bvFTD, emotion recognition impairment is driven by inaccurate perception of the internal milieu. Whereas, in AD and PD, cognitive impairment likely underlies emotion recognition deficits. The current study furthers our theoretical understanding of emotion and highlights the need for targeted interventions. (c, Funding Agencies|ForeFront; National Health and Medical Research Council (NHMRC) [GNT1037746]; Australian Research Council grant [DP170101815]; Takeda [CW2680521]; CONICET; FONCYT-PICT [2017-1818, 2017-1820]; ANID/FONDECYT [1,210,195, 1,210,176, 1,220,995]; ANID/FONDAP [15,150,012]; ANID/PIA/ANILLOS [ACT210096]; Multi-Partner Consortium to Expand Dementia Research in Latin America (ReDLat) - National Institutes of Aging of the National Institutes of Health [R01AG057234]; Alzheimers Association grant [SG-20-725707-ReDLat]; Rainwater Foundation; Global Brain Health Institute; NHMRC Senior Research Fellowship [GNT1103258]; NHMRC Career Development Fellowship [GNT1158762]

Disease-specific mechanisms underlying emotion recognition difficulties in behavioural -variant frontotemporal dementia (bvFTD), Alzheimers disease (AD), and Parkinsons dis-ease (PD) are unknown. Interoceptive accuracy, accurately detecting internal cues (e.g., ones heart beating), and cognitive abilities are candidate mechanisms underlying emotion recognition.One hundred and sixty-eight participants (52 bvFTD; 41 AD; 24 PD; 51 controls) were recruited. Emotion recognition was measured via the Facial Affect Selection Task or the Mini-Social and Emotional Assessment Emotion Recognition Task. Interoception was assessed with a heartbeat detection task. Participants pressed a button each time they: 1) felt their heartbeat (Interoception); or 2) heard a recorded heartbeat (Exteroception-con-trol). Cognition was measured via the Addenbrookes Cognitive Examination-III or the Montreal Cognitive Assessment. Voxel-based morphometry analyses identified neural correlates associated with emotion recognition and interoceptive accuracy. All patient groups showed worse emotion recognition and cognition than controls (all Ps < .008). Only the bvFTD showed worse interoceptive accuracy than controls (P < .001). Regression analyses revealed that in bvFTD worse interoceptive accuracy predicted worse emotion recognition (P = .008). Whereas worse cognition predicted worse emotion recogni-tion overall (P < .001). Neuroimaging analyses revealed that the insula, orbitofrontal cortex, and amygdala were involved in emotion recognition and interoceptive accuracy in bvFTD. Here, we provide evidence for disease-specific mechanisms for emotion recognition difficulties. In bvFTD, emotion recognition impairment is driven by inaccurate perception of the internal milieu. Whereas, in AD and PD, cognitive impairment likely underlies emotion recognition deficits. The current study furthers our theoretical understanding of emotion and highlights the need for targeted interventions. (c, Funding Agencies|ForeFront; National Health and Medical Research Council (NHMRC) [GNT1037746]; Australian Research Council grant [DP170101815]; Takeda [CW2680521]; CONICET; FONCYT-PICT [2017-1818, 2017-1820]; ANID/FONDECYT [1,210,195, 1,210,176, 1,220,995]; ANID/FONDAP [15,150,012]; ANID/PIA/ANILLOS [ACT210096]; Multi-Partner Consortium to Expand Dementia Research in Latin America (ReDLat) - National Institutes of Aging of the National Institutes of Health [R01AG057234]; Alzheimers Association grant [SG-20-725707-ReDLat]; Rainwater Foundation; Global Brain Health Institute; NHMRC Senior Research Fellowship [GNT1103258]; NHMRC Career Development Fellowship [GNT1158762]

Disease-specific mechanisms underlying emotion recognition difficulties in behavioural -variant frontotemporal dementia (bvFTD), Alzheimers disease (AD), and Parkinsons dis-ease (PD) are unknown. Interoceptive accuracy, accurately detecting internal cues (e.g., ones heart beating), and cognitive abilities are candidate mechanisms underlying emotion recognition.One hundred and sixty-eight participants (52 bvFTD; 41 AD; 24 PD; 51 controls) were recruited. Emotion recognition was measured via the Facial Affect Selection Task or the Mini-Social and Emotional Assessment Emotion Recognition Task. Interoception was assessed with a heartbeat detection task. Participants pressed a button each time they: 1) felt their heartbeat (Interoception); or 2) heard a recorded heartbeat (Exteroception-con-trol). Cognition was measured via the Addenbrookes Cognitive Examination-III or the Montreal Cognitive Assessment. Voxel-based morphometry analyses identified neural correlates associated with emotion recognition and interoceptive accuracy. All patient groups showed worse emotion recognition and cognition than controls (all Ps < .008). Only the bvFTD showed worse interoceptive accuracy than controls (P < .001). Regression analyses revealed that in bvFTD worse interoceptive accuracy predicted worse emotion recognition (P = .008). Whereas worse cognition predicted worse emotion recogni-tion overall (P < .001). Neuroimaging analyses revealed that the insula, orbitofrontal cortex, and amygdala were involved in emotion recognition and interoceptive accuracy in bvFTD. Here, we provide evidence for disease-specific mechanisms for emotion recognition difficulties. In bvFTD, emotion recognition impairment is driven by inaccurate perception of the internal milieu. Whereas, in AD and PD, cognitive impairment likely underlies emotion recognition deficits. The current study furthers our theoretical understanding of emotion and highlights the need for targeted interventions. (c, Funding Agencies|ForeFront; National Health and Medical Research Council (NHMRC) [GNT1037746]; Australian Research Council grant [DP170101815]; Takeda [CW2680521]; CONICET; FONCYT-PICT [2017-1818, 2017-1820]; ANID/FONDECYT [1,210,195, 1,210,176, 1,220,995]; ANID/FONDAP [15,150,012]; ANID/PIA/ANILLOS [ACT210096]; Multi-Partner Consortium to Expand Dementia Research in Latin America (ReDLat) - National Institutes of Aging of the National Institutes of Health [R01AG057234]; Alzheimers Association grant [SG-20-725707-ReDLat]; Rainwater Foundation; Global Brain Health Institute; NHMRC Senior Research Fellowship [GNT1103258]; NHMRC Career Development Fellowship [GNT1158762]

Disease-specific mechanisms underlying emotion recognition difficulties in behavioural -variant frontotemporal dementia (bvFTD), Alzheimers disease (AD), and Parkinsons dis-ease (PD) are unknown. Interoceptive accuracy, accurately detecting internal cues (e.g., ones heart beating), and cognitive abilities are candidate mechanisms underlying emotion recognition.One hundred and sixty-eight participants (52 bvFTD; 41 AD; 24 PD; 51 controls) were recruited. Emotion recognition was measured via the Facial Affect Selection Task or the Mini-Social and Emotional Assessment Emotion Recognition Task. Interoception was assessed with a heartbeat detection task. Participants pressed a button each time they: 1) felt their heartbeat (Interoception); or 2) heard a recorded heartbeat (Exteroception-con-trol). Cognition was measured via the Addenbrookes Cognitive Examination-III or the Montreal Cognitive Assessment. Voxel-based morphometry analyses identified neural correlates associated with emotion recognition and interoceptive accuracy. All patient groups showed worse emotion recognition and cognition than controls (all Ps < .008). Only the bvFTD showed worse interoceptive accuracy than controls (P < .001). Regression analyses revealed that in bvFTD worse interoceptive accuracy predicted worse emotion recognition (P = .008). Whereas worse cognition predicted worse emotion recogni-tion overall (P < .001). Neuroimaging analyses revealed that the insula, orbitofrontal cortex, and amygdala were involved in emotion recognition and interoceptive accuracy in bvFTD. Here, we provide evidence for disease-specific mechanisms for emotion recognition difficulties. In bvFTD, emotion recognition impairment is driven by inaccurate perception of the internal milieu. Whereas, in AD and PD, cognitive impairment likely underlies emotion recognition deficits. The current study furthers our theoretical understanding of emotion and highlights the need for targeted interventions. (c, Funding Agencies|ForeFront; National Health and Medical Research Council (NHMRC) [GNT1037746]; Australian Research Council grant [DP170101815]; Takeda [CW2680521]; CONICET; FONCYT-PICT [2017-1818, 2017-1820]; ANID/FONDECYT [1,210,195, 1,210,176, 1,220,995]; ANID/FONDAP [15,150,012]; ANID/PIA/ANILLOS [ACT210096]; Multi-Partner Consortium to Expand Dementia Research in Latin America (ReDLat) - National Institutes of Aging of the National Institutes of Health [R01AG057234]; Alzheimers Association grant [SG-20-725707-ReDLat]; Rainwater Foundation; Global Brain Health Institute; NHMRC Senior Research Fellowship [GNT1103258]; NHMRC Career Development Fellowship [GNT1158762]

Tumor evolution from a single cell into a malignant, heterogeneous tissue remains poorly understood. Here, we profile single-cell transcriptomes of genetically engineered mouse lung tumors at seven stages, from pre-neoplastic hyperplasia to adenocarcinoma. The diversity of transcriptional states increases over time and is reproducible across tumors and mice. Cancer cells progressively adopt alternate lineage identities, computationally predicted to be mediated through a common transitional, high-plasticity cell state (HPCS). Accordingly, HPCS cells prospectively isolated from mouse tumors and human patient-derived xenografts display high capacity for differentiation and proliferation. The HPCS program is associated with poor survival across human cancers and demonstrates chemoresistance in mice. Our study reveals a central principle underpinning intra-tumoral heterogeneity and motivates therapeutic targeting of the HPCS. Cellular states capable of promoting tumor progression and resisting therapies exist in heterogeneous tumors. Marjanovic et al. discover that a high-plasticity cell state common to mouse and human lung tumors drives cellular heterogeneity, is highly tumorigenic and drug resistant, and associates with poor patient prognosis.

An object-tracking algorithm was used on computed tomography (CT) images of the thorax from six healthy participants and nine participants with chronic obstructive pulmonary disease (COPD) to describe the movement of the ribs between the static lung volumes of functional residual capacity (FRC) and total lung capacity (TLC). The continuous motion of the ribs during tidal breathing was also described using four-dimensional CT datasets from seven participants with thoracic esophageal malignancies. Rib motion was defined relative to a local joint coordinate system where rotations about the axes that predominantly affected the anteroposterior and transverse diameters of the rib cage were referred to as pump-handle and bucket-handle movements, respectively. Between TLC and FRC, pump-handle movements were 1.8 times larger in healthy participants than in participants with COPD, in line with their 1.6 times larger inspiratory capacities. However, when rib motion was normalized to the change in lung volume, pump-handle movements were similar for healthy participants and participants with COPD. We found no differences in bucket-handle movements between participant groups before and after normalization. Pump-handle movement was the dominant rib motion between FRC and TLC, on average four times greater than bucket-handle movement in healthy participants. For expiratory tidal volume, pump-handle movements were 20% smaller than bucket-handle movements. When normalized to tidal volume and compared with inspiratory capacity, pump-handle movements were smaller and bucket-handle movements were larger during tidal breathing. The findings suggest that the pump-handle and bucket-handle components of rib motion vary for small and large changes in lung volume.

Studies of posttraumatic stress disorder (PTSD) report volume abnormalities in multiple regions of the cerebral cortex. However, findings for many regions, particularly regions outside commonly studied emotion-related prefrontal, insular, and limbic regions, are inconsistent and tentative. Also, few studies address the possibility that PTSD abnormalities may be confounded by comorbid depression. A mega-analysis investigating all cortical regions in a large sample of PTSD and control subjects can potentially provide new insight into these issues. Given this perspective, our group aggregated regional volumes data of 68 cortical regions across both hemispheres from 1379 PTSD patients to 2192 controls without PTSD after data were processed by 32 international laboratories using ENIGMA standardized procedures. We examined whether regional cortical volumes were different in PTSD vs. controls, were associated with posttraumatic stress symptom (PTSS) severity, or were affected by comorbid depression. Volumes of left and right lateral orbitofrontal gyri (LOFG), left superior temporal gyrus, and right insular, lingual and superior parietal gyri were significantly smaller, on average, in PTSD patients than controls (standardized coefficients = -0.111 to -0.068, FDR corrected P values < 0.039) and were significantly negatively correlated with PTSS severity. After adjusting for depression symptoms, the PTSD findings in left and right LOFG remained significant. These findings indicate that cortical volumes in PTSD patients are smaller in prefrontal regulatory regions, as well as in broader emotion and sensory processing cortical regions.

The inspiratory muscles, such as the diaphragm, receive descending neural inputs from the medulla and sensorimotor cortex. In response to increased respiratory demand or in the presence of respiratory impairment, the neural control of the inspiratory muscles adapts to meet ventilatory requirements. This thesis addresses the neural control of inspiration in health, healthy ageing and chronic tetraplegia. In the first two chapters of results, single motor unit electromyographic recordings of the costal diaphragm were performed in healthy people aged 23-80 years (Chapter 2) and in chronic tetraplegia (Chapter 3) during quiet breathing. The findings show that diaphragm motor unit discharge frequencies during quiet breathing do not change in healthy ageing but are increased in chronic tetraplegia. Diaphragm motor unit action potentials are larger in size in both healthy ageing and chronic tetraplegia, although more so in the latter group, which suggests motor unit remodelling. The difference between the two groups reflects the greater severity of respiratory motor impairment in chronic tetraplegia. Furthermore, ageing-related changes in diaphragm motor unit size were observed in middle age. The sensorimotor cortex is recruited during quiet breathing in certain conditions of respiratory impairment but not in healthy, younger people. In Chapter 4, electroencephalographic recordings were made from participants with chronic tetraplegia during quiet breathing. The results show that the sensorimotor cortex is not recruited which suggests that other sources of neural control, likely the medulla, generate the increase in diaphragm motor unit output during quiet breathing. In Chapter 5, electromyographic recordings were made from healthy people to investigate the simultaneous control of the costal and crural portions of the diaphragm with increased drive to breathe. Here, regardless of whether the source of increased drive is voluntary or involuntary, the costal portion of the di

"Tunirrusiangit, "their gifts" or "what they gave" in Inuktitut, celebrates the achievements of two remarkable artists who challenged the parameters of tradition while consistently articulating a compelling vision of the Inuit world view. Published to coincide with a major exhibition at the Art Gallery of Ontario, opening on 16 June and continuing until late August, Tunirrusiangit features more than 60 reproductions of paintings, drawings, and documentary photographs. Completing the book are essays by contemporary artists and curators Jocelyn Piirainen, Anna Hudson, Georgiana Uhlyarik, Koomuatuk Curley, Laakkuluk Williamson Bathory, and Taqralik Partridge that address both the past and future of Inuit identity." -- Publisher's website.

The museum world is in a time of great change, many of the changes focus on the accessibility of museums. In Sweden these changes are becoming more apparent as the new museum law that has been passed advocates for equal museum experience for all visitors whether they have any for of impairment or not. To encourage this change a few older law and regulations that Swedish museums are also subject to are receiving more attention. That is why this research project focuses on how accessible museum exhibits in Sweden are for the visually impaired, while also comparing and evaluating different methods used to make exhibits more accessible. Prior methods used to make exhibits more accessible for people with visual impairments from around the world have been researched to see what may be useful, in Swedish museum exhibits. Several specialists’ from inside and outside the museum world have been interviewed so as to provide relevant information on what type of changes would be most beneficial to a museum exhibit to make it more accessible for people with partial to no vision. A small research project has also been done to see how accessible several museums through Scania in Sweden are for people with various form of disabilities. The main segment of this paper focuses on an evaluation of methods to increase accessibility for people with visual impairments used in a temporary exhibit at Trelleborg’s Museum. These methods have been evaluated using qualitative research methods, such as observations, questionnaires and group interviews. The data was gathered using a test group comprised primarily of people with various levels of visual impairments and a control group meant to represent “regular” museum visitors. The conclusion of this research project is that new methods to make museum exhibits accessible for the visually impaired are constantly being invented, making methods that may seem too expensive and difficult to use much more efficient in the future. The most important poi

" Jock Macdonald was a pioneer of postwar abstraction in Canada. This retrospective publication of the Scottish-born artist's work offers a lively presentation of a career that spanned the country and greatly influenced twentieth century Canadian art. This sumptuously illustrated publication includes never-before-seen colour reproductions, texts by the curators and scholar Anna Hudson, correspondence with British Surrealists Grace W. Pailthorpe and Reuben Mednikoff, and a complete transcription of the artist's Nootka Diary, kept while living for a year in the trying conditions of Nootka Sound. " -- Publisher's website.

" Jock Macdonald was a pioneer of postwar abstraction in Canada. This retrospective publication of the Scottish-born artist's work offers a lively presentation of a career that spanned the country and greatly influenced twentieth century Canadian art. This sumptuously illustrated publication includes never-before-seen colour reproductions, texts by the curators and scholar Anna Hudson, correspondence with British Surrealists Grace W. Pailthorpe and Reuben Mednikoff, and a complete transcription of the artist's Nootka Diary, kept while living for a year in the trying conditions of Nootka Sound. " -- Publisher's website.

The objectives of the present study were to test the hypothesis that the costal diaphragm contracts during ipsilateral rotation of the trunk and that such trunk rotation increases the motor output of the muscle during inspiration. Monopolar electrodes were inserted in the right costal hemidiaphragm in six subjects, and electromyographic (EMG) recordings were made during isometric rotation efforts of the trunk to the right ("ipsilateral rotation") and to the left ("contralateral rotation"). EMG activity was simultaneously recorded from the parasternal intercostal muscles on the right side. The parasternal intercostals were consistently active during ipsilateral rotation but silent during contralateral rotation. In contrast, the diaphragm was silent in the majority of rotations in either direction, and whenever diaphragm activity was recorded, it involved very few motor units. In addition, whereas parasternal inspiratory activity substantially increased during ipsilateral rotation and decreased during contralateral rotation, inspiratory activity in the diaphragm was essentially unaltered and the discharge frequency of single motor units in the muscle remained at 13-14 Hz in the different postures. It is concluded that 1) the diaphragm makes no significant contribution to trunk rotation and 2) even though the diaphragm and parasternal intercostals contract in a coordinated manner during resting breathing, the inspiratory output of the two muscles is affected differently by voluntary drive during trunk rotation. © 2011 the American Physiological Society., SCOPUS: ar.j, info:eu-repo/semantics/published

The objectives of the present study were to test the hypothesis that the costal diaphragm contracts during ipsilateral rotation of the trunk and that such trunk rotation increases the motor output of the muscle during inspiration. Monopolar electrodes were inserted in the right costal hemidiaphragm in six subjects, and electromyographic (EMG) recordings were made during isometric rotation efforts of the trunk to the right ("ipsilateral rotation") and to the left ("contralateral rotation"). EMG activity was simultaneously recorded from the parasternal intercostal muscles on the right side. The parasternal intercostals were consistently active during ipsilateral rotation but silent during contralateral rotation. In contrast, the diaphragm was silent in the majority of rotations in either direction, and whenever diaphragm activity was recorded, it involved very few motor units. In addition, whereas parasternal inspiratory activity substantially increased during ipsilateral rotation and decreased during contralateral rotation, inspiratory activity in the diaphragm was essentially unaltered and the discharge frequency of single motor units in the muscle remained at 13-14 Hz in the different postures. It is concluded that 1) the diaphragm makes no significant contribution to trunk rotation and 2) even though the diaphragm and parasternal intercostals contract in a coordinated manner during resting breathing, the inspiratory output of the two muscles is affected differently by voluntary drive during trunk rotation. © 2011 the American Physiological Society., SCOPUS: ar.j, info:eu-repo/semantics/published

This thesis addresses the neural control of the human inspiratory muscles. Single motor unit and multiunit electromyographic recordings are made from inspiratory and limb muscles to investigate the organisation of inspiratory motoneurone output and strategies by which motoneurone output is optimised. In the first two chapters, the output of parasternal intercostal motor units in respiratory and non-respiratory ‘tasks’ are described. The results show that across parasternal intercostal spaces, there is a decreasing rostrocaudal gradient of motor unit output in targeted voluntary breaths, such that inspiratory activity is greatest and earliest in cranial interspaces. This topographic recruitment is similar to quiet breaths and the majority of motor units are active in both voluntary and quiet breaths. In a non-respiratory voluntary task, rotation of the trunk (Chapter 3), common motor units are also active, but inspiratory motor unit output on both sides of the chest wall is altered by unilateral rotation. Multiple descending drives to the respiratory muscles may be organised and integrated at the spinal cord such that the same motoneurones are depolarised but their output depends on the task(s) performed. The strategy of motor unit recruitment in two inspiratory muscles is examined in Chapter 4. The profiles of activation of an obligatory inspiratory muscle, scalenes, and an accessory muscle, sternocleidomastoid, are not altered by lung volume or task (isovolumetric ‘static’ versus ‘dynamic’ task). Rather than the activation of these muscles being dependent on afferent signals of lung volume, they are recruited according to their relative mechanical advantage for inspiration. These results suggest that neural drive to these muscles has an element that is ‘preset’. The final study investigates neural and mechanical behaviour in the first dorsal interosseous muscle. The results show that there is coupling between neural drive and

The parasternal intercostal muscles are obligatory inspiratory muscles. To test the hypothesis that they are also involved in trunk rotation and to assess the effect of any postural role on inspiratory drive to the muscles, intramuscular electromyographic (EMG) recordings were made from the parasternal intercostals on the right side in six healthy subjects during resting breathing in a neutral posture ("neutral breaths"), during an isometric axial rotation effort of the trunk to the right ("ipsilateral rotation") or left ("contralateral rotation"), and during resting breathing with the trunk rotated. The parasternal intercostals were commonly active during ipsilateral rotation but were consistently silent during contralateral rotation. In addition, with ipsilateral rotation, peak parasternal inspiratory activity was 201 ± 19% (mean ± SE) of the peak inspiratory activity in neutral breaths (P < 0.001), and activity commenced earlier relative to the onset of inspiratory flow. These changes resulted from an increase in the discharge frequency of motor units (14.3 ± 0.3 vs. 11.0 ± 0.3 Hz; P < 0.001) and the recruitment of new motor units. The majority of units that discharged during ipsilateral rotation were also active in inspiration. However, with contralateral rotation, parasternal inspiratory activity was delayed relative to the onset of inspiratory flow, and peak activity was reduced to 72 ± 4% of that in neutral breaths (P < 0.001). This decrease resulted from a decrease in the inspiratory discharge frequency of units (10.5 ± 0.2 vs. 12.0 ± 0.2 Hz; P < 0.001) and the derecruitment of units. These observations confirm that in addition to an inspiratory function, the parasternal intercostal muscles have a postural function. Furthermore the postural and inspiratory drives depolarize the same motoneurons, and the postural contraction of the muscles alters their output during inspiration in a direction-dependent manner. Copyright © 2010 The American Physiological Socie, SCOPUS: ar.j, info:eu-repo/semantics/published

The parasternal intercostal muscles are obligatory inspiratory muscles. To test the hypothesis that they are also involved in trunk rotation and to assess the effect of any postural role on inspiratory drive to the muscles, intramuscular electromyographic (EMG) recordings were made from the parasternal intercostals on the right side in six healthy subjects during resting breathing in a neutral posture ("neutral breaths"), during an isometric axial rotation effort of the trunk to the right ("ipsilateral rotation") or left ("contralateral rotation"), and during resting breathing with the trunk rotated. The parasternal intercostals were commonly active during ipsilateral rotation but were consistently silent during contralateral rotation. In addition, with ipsilateral rotation, peak parasternal inspiratory activity was 201 ± 19% (mean ± SE) of the peak inspiratory activity in neutral breaths (P < 0.001), and activity commenced earlier relative to the onset of inspiratory flow. These changes resulted from an increase in the discharge frequency of motor units (14.3 ± 0.3 vs. 11.0 ± 0.3 Hz; P < 0.001) and the recruitment of new motor units. The majority of units that discharged during ipsilateral rotation were also active in inspiration. However, with contralateral rotation, parasternal inspiratory activity was delayed relative to the onset of inspiratory flow, and peak activity was reduced to 72 ± 4% of that in neutral breaths (P < 0.001). This decrease resulted from a decrease in the inspiratory discharge frequency of units (10.5 ± 0.2 vs. 12.0 ± 0.2 Hz; P < 0.001) and the derecruitment of units. These observations confirm that in addition to an inspiratory function, the parasternal intercostal muscles have a postural function. Furthermore the postural and inspiratory drives depolarize the same motoneurons, and the postural contraction of the muscles alters their output during inspiration in a direction-dependent manner. Copyright © 2010 The American Physiological Socie, SCOPUS: ar.j, info:eu-repo/semantics/published

SCOPUS: ar.j, FLWIN, info:eu-repo/semantics/published

SCOPUS: ar.j, FLWIN, info:eu-repo/semantics/published

Originating from a series of workshops held at the Art Gallery of Ontario and the Vancouver Art Gallery in March 2000, the 24 essays in this book address the subject of Aboriginal representation in the gallery. The authors analyse issues stemming from the production, collection and exhibition of historical and contemporary Aboriginal art. Includes the programme for the workshop series. Text in English, with a French abstract. List of illustrations. Notes on contributors. Circa 450 bibl. ref.

Originating from a series of workshops held at the Art Gallery of Ontario and the Vancouver Art Gallery in March 2000, the 24 essays in this book address the subject of Aboriginal representation in the gallery. The authors analyse issues stemming from the production, collection and exhibition of historical and contemporary Aboriginal art. Includes the programme for the workshop series. Text in English, with a French abstract. List of illustrations. Notes on contributors. Circa 450 bibl. ref.

The artist identifies the natural and spiritual elements which permeate her paintings, while Hudson proposes the possibility of a redemptive experience for the viewer. Biographical notes.

The artist identifies the natural and spiritual elements which permeate her paintings, while Hudson proposes the possibility of a redemptive experience for the viewer. Biographical notes.