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The intraparietal sulcus (IPS) has been implicated in numerous functions that range from representation of visual stimuli to action planning, but its role in abstract decision-making has been unclear, in part because low-level functions often act as confounds. Here, we address this problem using a task that dissociates abstract decision-making from sensory salience, attentional control, motor planning, and motor output. Functional MRI data were collected from healthy female and male human subjects while they performed a policy abstraction task requiring use of a more abstract (second-order) rule to select between two less abstract (first order) rules that informed the motor response. By identifying IPS subdivisions with preferential connectivity to prefrontal regions that are differentially responsive to task abstraction, we found that a caudal IPS (cIPS) subregion with strongest connectivity to the pre-premotor cortex was preferentially active for second-order cues, whereas a rostral IPS subregion (rIPS) with strongest connectivity to the dorsal premotor cortex was active during attentional control over first-order cues. These effects for abstraction were seen in addition to cIPS activity that was specific to sensory salience, and rIPS activity that was specific to motor output. Notably, topographic responses to the second-order cue were detected along the caudal-rostral axis of IPS, mirroring the broader organization seen in lateral prefrontal cortex (Badre and D'Esposito, 2007). Together, these data demonstrate that subregions within IPS exhibit activity responsive to policy abstraction, and they suggest that IPS may be organized into frontoparietal subnetworks that support hierarchical cognitive control.SIGNIFICANCE STATEMENTAbstract decision-making allows us to flexibly adapt our behavior to new contexts. Although much previous work has focused on the role of lateral prefrontal cortex in such decisions, the contributions of parietal cortex have been relatively understudied. Here, we demonstrate that spatially segregated subregions of human IPS with strong functional connections to lateral prefrontal cortex demonstrate activity selective for abstract decisions. This activity can be distinguished from responses because of cognitive processes related to sensory salience, attentional control, motor planning, and movement. Together, these findings indicate that different task demands are reflected in the topography of IPS, and they explicitly reveal a role in abstract decision-making.
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INTRODUCTION: The benefits of exercise in reducing treatment-related morbidity and improving quality of life following a primary diagnosis of cancer have been well documented and have led to exercise being recommended by oncology societies for all people with a cancer diagnosis. However, these recommendations are derived from research typically involving cohorts with more common cancers and relatively good prognosis, such as breast and prostate. Evidence from these cancers may not apply to women with recurrent ovarian cancer. Therefore, the primary objective of this trial is to evaluate the feasibility and safety of a home-based, telephone-delivered exercise intervention for women undergoing chemotherapy for recurrent ovarian cancer. METHODS AND ANALYSIS: The Exercise During Chemotherapy for Recurrent Ovarian Cancer (ECHO-R) trial is a single-arm, phase II, pre/postintervention trial of a 6-month, telephone-delivered exercise intervention (consistent with recommended exercise oncology prescription). The target sample size is 80 women who are currently undergoing (or are scheduled to receive) chemotherapy for recurrent ovarian cancer. Recruitment is through participating hospital sites in Queensland, Australia, or via self-referral. The exercise intervention comprises 12 telephone sessions over a 6-month period delivered by trial-trained exercise professionals and supplemented (where feasible) by five sessions face to face. Exercise prescription is individualised and works towards an overall goal of achieving a weekly target of 150 min of moderate-intensity, mixed-mode exercise. Assessments via self-administered survey and physical fitness and function tests occur at baseline and then at 6 and 9 months postbaseline. Data to inform feasibility and safety are recorded as case notes by the exercise professional during each session. ETHICS AND DISSEMINATION: Ethics approval for the ECHO-R trial was granted by the Metro North Human Research Ethics Committee (HREC/2020/QRBW/67223) on 6 November 2020. Findings from the trial are planned to be disseminated via peer-reviewed publications and both national and international exercise and oncology conferences. TRIAL REGISTRATION NUMBER: ACTRN12621000042842.
Assuntos
Neoplasias Ovarianas , Qualidade de Vida , Feminino , Humanos , Masculino , Carcinoma Epitelial do Ovário , Terapia por Exercício/efeitos adversos , Estudos de Viabilidade , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/etiologia , TelefoneRESUMO
BACKGROUND: Exercise interventions during adjuvant cancer therapy have been shown to increase functional capacity, relieve fatigue and distress and may assist rates of chemotherapy completion. These studies have been limited to breast, gastric and mixed cancer groups and it is not yet known if a similar intervention is even feasible among women with ovarian cancer. We aimed to assess safety, feasibility and potential effect of a walking intervention in women undergoing chemotherapy for ovarian cancer. METHODS: Women newly diagnosed with ovarian cancer were recruited to participate in an individualised walking intervention throughout chemotherapy and were assessed pre- and post-intervention. Feasibility measures included session adherence, compliance with exercise physiologist prescribed walking targets and self-reported program acceptability. Changes in objective physical functioning (6-minute walk test), self-reported distress (Hospital Anxiety and Depression Scale), symptoms (Memorial Symptom Assessment Scale - Physical) and quality of life (Functional Assessment of Cancer Therapy - Ovarian) were calculated, and chemotherapy completion and adverse intervention effects recorded. RESULTS: Seventeen women were enrolled (63% recruitment rate). Mean age was 60 years (SD = 8 years), 88% were diagnosed with FIGO stage III or IV disease, 14 women underwent adjuvant and three neo-adjuvant chemotherapy. On average, women adhered to > 80% of their intervention sessions and complied with 76% of their walking targets, with the majority walking four days a week at moderate intensity for 30 minutes per session. Meaningful improvements were found in physical functioning, physical symptoms, physical well-being and ovarian cancer-specific quality of life. Most women (76%) completed ≥85% of their planned chemotherapy dose. There were no withdrawals or serious adverse events and all women reported the program as being helpful. CONCLUSIONS: These positive preliminary results suggest that this walking intervention for women receiving chemotherapy for ovarian cancer is safe, feasible and acceptable and could be used in development of future work. TRIAL REGISTRATION: ACTRN12609000252213.
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Terapia por Exercício , Neoplasias Ovarianas/reabilitação , Caminhada , Adulto , Idoso , Antineoplásicos/uso terapêutico , Terapia por Exercício/efeitos adversos , Feminino , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/patologia , Projetos Piloto , Resultado do TratamentoRESUMO
Higher-order thalamic nuclei, such as the visual pulvinar, play essential roles in cortical function by connecting functionally related cortical and subcortical brain regions. A coherent framework describing pulvinar function remains elusive because of its anatomical complexity and involvement in diverse cognitive processes. We combined large-scale anatomical circuit mapping with high-density electrophysiological recordings to dissect a homolog of the pulvinar in mice, the lateral posterior thalamic nucleus (LP). We define three broad LP subregions based on correspondence between connectivity and functional properties. These subregions form corticothalamic loops biased toward ventral or dorsal stream cortical areas and contain separate representations of visual space. Silencing the visual cortex or superior colliculus revealed that they drive visual tuning properties in separate LP subregions. Thus, by specifying the driving input sources, functional properties, and downstream targets of LP circuits, our data provide a roadmap for understanding the mechanisms of higher-order thalamic function in vision.
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Pulvinar/fisiologia , Colículos Superiores/fisiologia , Córtex Visual/fisiologia , Vias Visuais/fisiologia , Animais , Mapeamento Encefálico , Eletroencefalografia , Camundongos , Tálamo/fisiologiaRESUMO
BACKGROUND: Low and moderate dose anthracycline therapy used in current treatment protocols, may be associated with subclinical abnormalities of cardiac function and late presentation with congestive heart failure. Exercise echocardiography is a useful and non-invasive means of uncovering latent cardiac dysfunction in other settings. The purpose of this study is to determine whether exercise echocardiography has the potential to detect subclinical abnormalities of cardiac function in children treated with anthracyclines. PROCEDURE: One hundred ten children previously treated with anthracycline, in remission and off treatment for >12 months were assessed, together with 31 control subjects. Each subject had a resting ECG and echocardiogram performed, and following exercise on a treadmill according to the Bruce protocol, a repeat echocardiogram was performed. RESULTS: Cumulative anthracycline dose was the only patient variable related to any of the outcome measures. Resting fractional shortening was normal in the majority of treated patients but was inversely related to cumulative anthracycline dose (rate of decline 1.2%/100 mg/m(2)). Following peak exercise, the inverse relationship between fractional shortening and anthracycline dose was more pronounced (rate 2.7%/100 mg/m(2)). CONCLUSIONS: Higher anthracycline doses are associated with a greater difference in peak fractional shortening between treated subjects and controls. Exercise echocardiography is a simple, relatively inexpensive tool that may enhance the detection of latent cardiac dysfunction after anthracycline administration during childhood.