Individuals who have suffered a severe brain injury typically require extensive hospitalization in intensive care units (ICUs), where critical treatment decisions are made to maximize their likelihood of recovering consciousness and cognitive function. These treatment decisions can be difficult when the neurological assessment of the patient is limited by unreliable behavioral responses. Reliable objective and quantifiable markers are lacking and there is both (1) a poor understanding of the mechanisms underlying the brain's ability to reconstitute consciousness and cognition after an injury and (2) the absence of a reliable and clinically feasible method of tracking cognitive recovery in ICU survivors. Our goal is to develop and validate a clinically relevant EEG paradigm that can inform the prognosis of unresponsive, brain-injured patients in the ICU. This protocol describes a study to develop a point-of-care system intended to accurately predict outcomes of unresponsive, brain-injured patients in the ICU. We will recruit 200 continuously-sedated brain-injured patients across five ICUs. Between 24 h and 7 days post-ICU admission, high-density EEG will be recorded from behaviorally unresponsive patients before, during and after a brief cessation of pharmacological sedation. Once patients have reached the waking stage, they will be asked to complete an abridged Cambridge Brain Sciences battery, a web-based series of neurocognitive tests. The test series will be repeated every day during acute admission (ICU, ward), or as often as possible given the constraints of ICU and ward care. Following discharge, patients will continue to complete the same test series on weekly, and then monthly basis, for up to 12 months following injury. Functional outcomes will also be assessed up to 12 months post-injury. We anticipate our findings will lead to an increased ability to identify patients, as soon as possible after their brain injury, who are most likely to survive, and to make accurate predictions about their long-term cognitive and functional outcome. In addition to providing critically needed support for clinical decision-making, this study has the potential to transform our understanding of key functional EEG networks associated with consciousness and cognition.
(1) Background: Although cognitive impairments in coma survivors are common, methods of measuring long-term cognitive outcomes in this population are inconsistent, precluding the development of a strong evidence-base to support clinical decision making. In this literature review, we identify and characterize the measures used to track cognitive recovery in coma survivors to data. (2) Methods: We extracted the instrument used for cognitive assessment, the cognitive domains assessed, methods administration and scoring, and timing of assessment from 134 of 996 screened records. (3) Results: A total of 133 unique cognitive tests and cognitive testing batteries were identified, with 97 cognitive instruments used in less than three articles. The instruments assessed 20 different cognitive domains, with 73 articles also using tests that assess general “cognitive ability”. Cognitive instruments ranged from subjective assessments to comprehensive cognitive batteries. There were inconsistent points of reference for the timing of assessment across studies, with few studies repeating assessments at more than one time point, and arbitrary time intervals between tests. (4) Conclusions: Overall, this review illustrates the enormous disparity between studies that track cognitive outcome in coma survivors, and the need for a systematic, patient-accessible method of assessing cognitive functioning in future studies with this population.
Accurate assessment of level of consciousness and potential to recover in severe brain injury patients underpins crucial decisions in the intensive care unit but remains a major challenge for the clinical team. The neurological wake-up test (NWT) is a widely used assessment tool, but many patients' behavioral response during a short interruption of sedation is ambiguous or absent, with little prognostic value. This study assesses the brain's electroencephalogram response during an interruption of propofol sedation to complement behavioral assessment during the NWT to predict survival, recovery of consciousness, and long-term functional outcome in acute severe brain injury patients. We recorded 128-channel EEG of 41 severely brain-injured patients during a clinically indicated NWT. The Glasgow Coma Scale (GCS) was used to assess behavioral responsiveness before and after interruption of sedation (GCS_observed). During the NWT, nine patients regained responsiveness, 13 patients showed ambiguous responsiveness and 19 patients were not responsive. Brain response to sedation interruption was quantified using EEG power, spatial ratios and the spectral exponent. We trained a linear regression model to identify brain patterns related to regaining behavioral responsiveness. We then applied this model to patients whose behavioral responses were ambiguous or absent, using their NWT brain responses to predict a change in behavioral response (Delta_GCS_predicted). Prognostic value of the Delta_GCS_predicted was assessed using the Mann-Whitney-U test and group-separability. The patients' survival, recovery of responsiveness, and functional outcomes were assessed up to 12 months post-recording. EEG patterns during interruption of sedation reliably predicted the GCS_observed in patients who regained responsiveness during the NWT. Electrophysiological patterns of waking-up were observed in some patients whose behavioral response was ambiguous or absent. Compared to the GCS_observed, the Delta_GCS_predicted improved separability of prognostic groups and significantly distinguished patients according to survival (U = 87, p<0.05). The EEG-trained model outperformed outcome predictions of the patients' attending physician and predictions based on the patients' APACHE score. EEG can complement behavioral assessment during the NWT to improve prognostication, inform clinicians, family members and caregivers, and to set realistic goals for treatment and therapy.
Research is mixed on whether playing a musical instrument leads to generalised cognitive benefits, and in which domains these improvements occur. Here, we leveraged a large (>6,000) sample of demographically-matched participants who either reported playing an instrument, or reported playing no instruments. Participants completed a well-established online battery of cognitive tasks to determine whether differences existed, and if so, in which cognitive domains. Linear regression, controlling for demographic variables, was used to examine differences between instrumentalists and non-instrumentalists. Follow-up analyses examined whether the number of instruments played predicted scores, and whether certain types of instrumentalists outperformed others. Robust group differences were found on eight cognitive tests, and in all cases instrumentalists outperformed non- instrumentalists. However, all of these effects were so small that they are unlikely to translate to any meaningful differences between individuals with or without musical experience. Cognitive scores correlated with number of instruments on nine tests, but no systematic differences existed between types of instrumentalists. While a causal relationship cannot be unequivocally confirmed, we propose that there may be some, albeit modest, transfer from musical experience to certain cognitive domains, and that these benefits scale with number of instruments played.
Background: Arts-based programs can counter the dominant narrative of loss associated with dementia, in part through fostering expressions of agency. This study uses social science theories of interaction between structure and agency to examine how an arts-based movement program, entitled Mouvement de passage, supports agency among individuals with dementia. Methods: Ethnographic methods were used to trace how participants enact agency within the structure of the movement program. The program's sessions were video recorded and iteratively analyzed. Results: Participants expressed their agency in three ways: 1) transforming the exercise's structure according to individual interests and desires; 2) resisting the exercise's structure; and 3) improvising movements collectively. Conclusions: The movements of individuals with dementia were shaped by both program structure and individual/collective expressions of agency. The design of Mouvement de passage, based on open-ended structures and voluntary participation, provides a template for developing interventions that foster agency among these persons.
One of the challenging consequences of dementia is the change in relationships that can co-occur with the progression of this condition. Despite this well-documented change, few arts-based interventions target the relational dimension of dementia. This study aims to explore the effects of one arts-based relational intervention: a movement program designed to foster connections within a group of persons with dementia. We used ethnographic methods-including participant observations and informal interviews-to understand the relational effects of this program conducted by two dancers and a musician. The movement sessions were video recorded, and participant movement trajectories were analyzed for different ways in which they created connections. We identified two types of connections-nonreciprocal and reciprocal-and four subtypes of connections-connection to exercise/music, connection to participant, interpersonal connection, and group connection-that participants engaged in during the movement program. Despite most participants not remembering the previous movement sessions, they experienced increasing numbers of connections over the course of the program, particularly reciprocal interpersonal connections. Participants explored new forms of moving and creatively transformed the movement structures proposed by the dancers. The results demonstrate the effectiveness of this program in augmenting connections and fostering exploration and creativity in individuals with dementia, providing a template for further developments of interventions targeting the relational dimensions of dementia. This study also highlights the potential of combining ethnographic methods and video analysis to include the perspectives of persons with dementia in research.
