Priority coding in the visual system.

Although we are continuously bombarded with visual input, only a fraction of incoming visual events is perceived, remembered or acted on. The neural underpinnings of various forms of visual priority coding, including perceptual expertise, goal-directed attention, visual salience, image memorability and preferential looking, have been studied. Here, we synthesize information from these different examples to review recent developments in our understanding of visual priority coding and its neural correlates, with a focus on the role of behaviour to evaluate candidate correlates. We propose that the brain combines different types of priority into a unified priority signal while also retaining the ability to differentiate between them, and that this happens by leveraging partially overlapping low-dimensional neural subspaces for each type of priority that are shared with the downstream neural populations involved in decision-making. Finally, we describe the gulfs in understanding that have resulted from different research approaches, and we point towards future directions that will lead to fundamental insights about neural coding and how prioritization influences visually guided behaviours.

Cognition as a Window into Neuronal Population Space.

Understanding how cognitive processes affect the responses of sensory neurons may clarify the relationship between neuronal population activity and behavior. However, tools for analyzing neuronal activity have not kept up with technological advances in recording from large neuronal populations. Here, we describe prevalent hypotheses of how cognitive processes affect sensory neurons, driven largely by a model based on the activity of single neurons or pools of neurons as the units of computation. We then use simple simulations to expand this model to a new conceptual framework that focuses on subspaces of population activity as the relevant units of computation, uses comparisons between brain areas or to behavior to guide analyses of these subspaces, and suggests that population activity is optimized to decode the large variety of stimuli and tasks that animals encounter in natural behavior. This framework provides new ways of understanding the ever-growing quantity of recorded population activity data.

Topological insights into the neural basis of flexible behavior.

It is widely accepted that there is an inextricable link between neural computations, biological mechanisms, and behavior, but it is challenging to simultaneously relate all three. Here, we show that topological data analysis (TDA) provides an important bridge between these approaches to studying how brains mediate behavior. We demonstrate that cognitive processes change the topological description of the shared activity of populations of visual neurons. These topological changes constrain and distinguish between competing mechanistic models, are connected to subjects' performance on a visual change detection task, and, via a link with network control theory, reveal a tradeoff between improving sensitivity to subtle visual stimulus changes and increasing the chance that the subject will stray off task. These connections provide a blueprint for using TDA to uncover the biological and computational mechanisms by which cognition affects behavior in health and disease.

Methylphenidate as a causal test of translational and basic neural coding hypotheses.

Most systems neuroscience studies fall into one of two categories: basic science work aimed at understanding the relationship between neurons and behavior, or translational work aimed at developing treatments for neuropsychiatric disorders. Here we use these two approaches to inform and enhance each other. Our study both tests hypotheses about basic science neural coding principles and elucidates the neuronal mechanisms underlying clinically relevant behavioral effects of systemically administered methylphenidate (Ritalin). We discovered that orally administered methylphenidate, used clinically to treat attention deficit hyperactivity disorder (ADHD) and generally to enhance cognition, increases spatially selective visual attention, enhancing visual performance at only the attended location. Further, we found that this causal manipulation enhances vision in rhesus macaques specifically when it decreases the mean correlated variability of neurons in visual area V4. Our findings demonstrate that the visual system is a platform for understanding the neural underpinnings of both complex cognitive processes (basic science) and neuropsychiatric disorders (translation). Addressing basic science hypotheses, our results are consistent with a scenario in which methylphenidate has cognitively specific effects by working through naturally selective cognitive mechanisms. Clinically, our findings suggest that the often staggeringly specific symptoms of neuropsychiatric disorders may be caused and treated by leveraging general mechanisms.

Low rank mechanisms underlying flexible visual representations.

Neuronal population responses to sensory stimuli are remarkably flexible. The responses of neurons in visual cortex have heterogeneous dependence on stimulus properties (e.g., contrast), processes that affect all stages of visual processing (e.g., adaptation), and cognitive processes (e.g., attention or task switching). Understanding whether these processes affect similar neuronal populations and whether they have similar effects on entire populations can provide insight into whether they utilize analogous mechanisms. In particular, it has recently been demonstrated that attention has low rank effects on the covariability of populations of visual neurons, which impacts perception and strongly constrains mechanistic models. We hypothesized that measuring changes in population covariability associated with other sensory and cognitive processes could clarify whether they utilize similar mechanisms or computations. Our experimental design included measurements in multiple visual areas using four distinct sensory and cognitive processes. We found that contrast, adaptation, attention, and task switching affect the variability of responses of populations of neurons in primate visual cortex in a similarly low rank way. These results suggest that a given circuit may use similar mechanisms to perform many forms of modulation and likely reflects a general principle that applies to a wide range of brain areas and sensory, cognitive, and motor processes.

Tai Chi as a Complementary Therapy for Depression and Anxiety Among U.S. Veterans in a Mental Health Inpatient Setting.

BACKGROUND: Depression and anxiety are two of the top five mental illnesses veterans report. Treatment for depression and anxiety includes medications and psychiatric treatment in inpatient, outpatient, and residential treatment programs; the use of complementary and alternative medicine (CAM) can have beneficial results by decreasing symptoms, recognize patients' preference for CAM, and be cost-effective. AIM: This study aimed to evaluate the effects of Tai Chi on depression and anxiety symptoms on inpatient psychosocial or substance use disorder (SUD) rehabilitation treatment program residents since little evidence exists regarding the effectiveness of Tai Chi on participants in residential mental health treatment programs. METHOD: A mixed-method, cohort design with 88 participants (41 usual treatment without Tai Chi, 47 intervention) used a demographic survey, Hamilton Anxiety Scale, Quick Inventory of Depressive Symptomatology, self-report, and the Patient Health Questionnaire-9 at Weeks 1 and 4 of the treatment program. After Week 4, the intervention group responded to six open-ended questions about Tai Chi's effects on their overall depression and anxiety. RESULTS: The anxiety level of the intervention group was significantly decreased, as evidenced by the Hamilton Anxiety Scale scores (p = .02). However, the measures of depression did not differ between the groups. Two themes, mindfulness and satisfaction, were identified from the written responses regarding the Tai Chi intervention. CONCLUSION: Tai Chi effectively reduced symptoms of anxiety that varied by age and ethnicity. This study increased the insight regarding the benefit of including Tai Chi as a complementary therapy for those participating in residential treatment programs.

Effects of Implementing an Acuity Tool on a Psychiatric Intensive Care Unit.

BACKGROUND: Staff shortages, reduced budgets, and high acuity of violent psychiatric patients can create challenges in psychiatric intensive care units (PICUs). LOCAL PROBLEM: Staffing of the psychiatric unit was based on patient census rather than evidence-based practices. METHODS: A pre-/postintervention design was used to examine changes in nursing satisfaction and patient outcomes as measured with the National Database of Nursing Quality Indicators (NDNQI) survey results. INTERVENTIONS: A psychiatric specific acuity tool was implemented on the PICU of a Veterans Administration hospital. RESULTS: After an initial decrease related to the COVID-19 pandemic, total acuity and the total number of nurses remained relatively stable while the unit census declined. NDNQI survey results improved with the largest being a 52-percentile increase for the quality-of-care summary measure. CONCLUSIONS: An acuity tool can help standardize practice, determine fair patient assignments among staff, increase nurse satisfaction, and promote best practices for patient safety.

Cancer as Communal: Understanding Communication and Relationships from the Perspectives of Survivors, Family Caregivers, and Health Care Providers.

With cancer increasing in prevalence and high priorities placed on concurrent oncological and palliative care to help meet the familial, spiritual, and individual needs of stakeholders in cancer, research is needed that assesses the factors that facilitate coping across stakeholders in cancer care. We were interested in synthesizing our understanding of communication and relationships among patients, caregivers, and providers based on the reasoning that illness is relational, but often conceptualized and researched from the individual perspectives of various stakeholders. The current study examined the experiences of relational and communication opportunities and challenges during cancer for current and former family caregivers, cancer survivors, and palliative and oncology health care practitioners. The thematic analysis of 30 semi-structured interviews revealed an overarching theme on the benefits of orienting toward cancer as communal, which was, in turn, facilitated or impeded by four additional themes/sets of behaviors: support, presence, perspective-taking, and reframing hope. Results of a cross-case data matrix analysis reveal that stakeholders in different roles experience qualitative differences in their experience of cancer as communal, isolated, or ambivalent. Implications for education, palliative care, and interventions are discussed.

Decision-related activity in sensory neurons: correlations among neurons and with behavior.

Neurons in early sensory cortex show weak but systematic correlations with perceptual decisions when trained animals perform at psychophysical threshold. These correlations are observed across repeated presentations of identical stimuli and cannot be explained by variation in external factors. The relationship between the activity of individual sensory neurons and the animal's behavioral choice means that even neurons in early sensory cortex carry information about an upcoming decision. This relationship, termed choice probability, may reflect the effect of fluctuations in neuronal firing rate on the animal's decision, but it can also reflect modulation of sensory responses by cognitive factors, or network properties such as variability that is shared among populations of neurons. Here, we review recent work clarifying the relationship among fluctuations in the responses of individual neurons, correlated variability, and behavior in a variety of tasks and cortical areas. We also discuss the possibility that choice probability may in part reflect the influence of cognitive factors on sensory neurons and explore the situations in which choice probability can be used to make inferences about the role of particular sensory neurons in the decision-making process.

A normalization model suggests that attention changes the weighting of inputs between visual areas.

Models of divisive normalization can explain the trial-averaged responses of neurons in sensory, association, and motor areas under a wide range of conditions, including how visual attention changes the gains of neurons in visual cortex. Attention, like other modulatory processes, is also associated with changes in the extent to which pairs of neurons share trial-to-trial variability. We showed recently that in addition to decreasing correlations between similarly tuned neurons within the same visual area, attention increases correlations between neurons in primary visual cortex (V1) and the middle temporal area (MT) and that an extension of a classic normalization model can account for this correlation increase. One of the benefits of having a descriptive model that can account for many physiological observations is that it can be used to probe the mechanisms underlying processes such as attention. Here, we use electrical microstimulation in V1 paired with recording in MT to provide causal evidence that the relationship between V1 and MT activity is nonlinear and is well described by divisive normalization. We then use the normalization model and recording and microstimulation experiments to show that the attention dependence of V1-MT correlations is better explained by a mechanism in which attention changes the weights of connections between V1 and MT than by a mechanism that modulates responses in either area. Our study shows that normalization can explain interactions between neurons in different areas and provides a framework for using multiarea recording and stimulation to probe the neural mechanisms underlying neuronal computations.

Neuronal population mechanisms of lightness perception.

The way that humans and animals perceive the lightness of an object depends on its physical luminance as well as its surrounding context. While neuronal responses throughout the visual pathway are modulated by context, the relationship between neuronal responses and lightness perception is poorly understood. We searched for a neuronal mechanism of lightness by recording responses of neuronal populations in monkey primary visual cortex (V1) and area V4 to stimuli that produce a lightness illusion in humans, in which the lightness of a disk depends on the context in which it is embedded. We found that the way individual units encode the luminance (or equivalently for our stimuli, contrast) of the disk and its context is extremely heterogeneous. This motivated us to ask whether the population representation in either V1 or V4 satisfies three criteria: 1) disk luminance is represented with high fidelity, 2) the context surrounding the disk is also represented, and 3) the representations of disk luminance and context interact to create a representation of lightness that depends on these factors in a manner consistent with human psychophysical judgments of disk lightness. We found that populations of units in both V1 and V4 fulfill the first two criteria but that we cannot conclude that the two types of information in either area interact in a manner that clearly predicts human psychophysical measurements: the interpretation of our population measurements depends on how subsequent areas read out lightness from the population responses. NEW & NOTEWORTHY A core question in visual neuroscience is how the brain extracts stable representations of object properties from the retinal image. We searched for a neuronal mechanism of lightness perception by determining whether the responses of neuronal populations in primary visual cortex and area V4 could account for a lightness illusion measured using human psychophysics. Our results suggest that comparing psychophysics with population recordings will yield insight into neuronal mechanisms underlying a variety of perceptual phenomena.

Attention Increases Spike Count Correlations between Visual Cortical Areas.

UNLABELLED: Visual attention, which improves perception of attended locations or objects, has long been known to affect many aspects of the responses of neuronal populations in visual cortex. There are two nonmutually exclusive hypotheses concerning the neuronal mechanisms that underlie these perceptual improvements. The first hypothesis, that attention improves the information encoded by a population of neurons in a particular cortical area, has considerable physiological support. The second hypothesis is that attention improves perception by selectively communicating relevant visual information. This idea has been tested primarily by measuring interactions between neurons on very short timescales, which are mathematically nearly independent of neuronal interactions on longer timescales. We tested the hypothesis that attention changes the way visual information is communicated between cortical areas on longer timescales by recording simultaneously from neurons in primary visual cortex (V1) and the middle temporal area (MT) in rhesus monkeys. We used two independent and complementary approaches. Our correlative experiment showed that attention increases the trial-to-trial response variability that is shared between the two areas. In our causal experiment, we electrically microstimulated V1 and found that attention increased the effect of stimulation on MT responses. Together, our results suggest that attention affects both the way visual stimuli are encoded within a cortical area and the extent to which visual information is communicated between areas on behaviorally relevant timescales. SIGNIFICANCE STATEMENT: Visual attention dramatically improves the perception of attended stimuli. Attention has long been thought to act by selecting relevant visual information for further processing. It has been hypothesized that this selection is accomplished by increasing communication between neurons that encode attended information in different cortical areas. We recorded simultaneously from neurons in primary visual cortex and the middle temporal area while rhesus monkeys performed an attention task. We found that attention increased shared variability between neurons in the two areas and that attention increased the effect of microstimulation in V1 on the firing rates of MT neurons. Our results provide support for the hypothesis that attention increases communication between neurons in different brain areas on behaviorally relevant timescales.

Stimulus Dependence of Correlated Variability across Cortical Areas.

UNLABELLED: The way that correlated trial-to-trial variability between pairs of neurons in the same brain area (termed spike count or noise correlation, rSC) depends on stimulus or task conditions can constrain models of cortical circuits and of the computations performed by networks of neurons (Cohen and Kohn, 2011). In visual cortex, rSC tends not to depend on stimulus properties (Kohn and Smith, 2005; Huang and Lisberger, 2009) but does depend on cognitive factors like visual attention (Cohen and Maunsell, 2009; Mitchell et al., 2009). However, neurons across visual areas respond to any visual stimulus or contribute to any perceptual decision, and the way that information from multiple areas is combined to guide perception is unknown. To gain insight into these issues, we recorded simultaneously from neurons in two areas of visual cortex (primary visual cortex, V1, and the middle temporal area, MT) while rhesus monkeys viewed different visual stimuli in different attention conditions. We found that correlations between neurons in different areas depend on stimulus and attention conditions in very different ways than do correlations within an area. Correlations across, but not within, areas depend on stimulus direction and the presence of a second stimulus, and attention has opposite effects on correlations within and across areas. This observed pattern of cross-area correlations is predicted by a normalization model where MT units sum V1 inputs that are passed through a divisive nonlinearity. Together, our results provide insight into how neurons in different areas interact and constrain models of the neural computations performed across cortical areas. SIGNIFICANCE STATEMENT: Correlations in the responses of pairs of neurons within the same cortical area have been a subject of growing interest in systems neuroscience. However, correlated variability between different cortical areas is likely just as important. We recorded simultaneously from neurons in primary visual cortex and the middle temporal area while rhesus monkeys viewed different visual stimuli in different attention conditions. We found that correlations between neurons in different areas depend on stimulus and attention conditions in very different ways than do correlations within an area. The observed pattern of cross-area correlations was predicted by a simple normalization model. Our results provide insight into how neurons in different areas interact and constrain models of the neural computations performed across cortical areas.

Relating normalization to neuronal populations across cortical areas.

Normalization, which divisively scales neuronal responses to multiple stimuli, is thought to underlie many sensory, motor, and cognitive processes. In every study where it has been investigated, neurons measured in the same brain area under identical conditions exhibit a range of normalization, ranging from suppression by nonpreferred stimuli (strong normalization) to additive responses to combinations of stimuli (no normalization). Normalization has been hypothesized to arise from interactions between neuronal populations, either in the same or different brain areas, but current models of normalization are not mechanistic and focus on trial-averaged responses. To gain insight into the mechanisms underlying normalization, we examined interactions between neurons that exhibit different degrees of normalization. We recorded from multiple neurons in three cortical areas while rhesus monkeys viewed superimposed drifting gratings. We found that neurons showing strong normalization shared less trial-to-trial variability with other neurons in the same cortical area and more variability with neurons in other cortical areas than did units with weak normalization. Furthermore, the cortical organization of normalization was not random: neurons recorded on nearby electrodes tended to exhibit similar amounts of normalization. Together, our results suggest that normalization reflects a neuron's role in its local network and that modulatory factors like normalization share the topographic organization typical of sensory tuning properties.

Evaluation of two instruments of perceived symptom intensity in palliative care patients in an outpatient clinic.

AIMS AND OBJECTIVES: To evaluate the test-retest stability in assessments of perceived symptom intensity on the Edmonton Symptom Assessment System-revised and the European Organization for Research and Treatment of Cancer, Quality of Life Questionnaire Core 15 Palliative. The possible interchangeability between the instruments and the patients' experiences of completing the instruments were also studied. BACKGROUND: The two instruments assess the same symptoms, but the symptom intensity is assessed on 11-point numerical scales on the Edmonton Symptom Assessment System-revised and on four-point verbal descriptive scales on the European Organization for Research and Treatment of Cancer, Quality of Life Questionnaire Core 15 Palliative. Both instruments are commonly used; however, uncertainty exists about which instrument should be recommended and about the interchangeability of the instruments. DESIGN: This study used a test-retest design with inter-scale comparisons. METHODS: Data from 54 patients with cancer who were receiving palliative care in an oncology outpatient clinic were self-reported by the patients in the clinic, at home and when patients returned to the clinic. RESULTS: The assessments on the European Organization for Research and Treatment of Cancer, Quality of Life Questionnaire Core 15 Palliative verbal rating scales showed a higher level of test-retest stability than the assessments on the Edmonton Symptom Assessment System-revised numerical scoring scales, indicating higher reliability. The correspondence between the verbal categories and the numerical scores of symptom intensity were low because different verbal categories were used by patients who assessed the same numerical score. CONCLUSIONS: The test-retest stability in the assessments was higher on the European Organization for Research and Treatment of Cancer, Quality of Life Questionnaire Core 15 Palliative and the results show that assessments on the two instruments could not be used interchangeably. Therefore, the symptom instrument chosen must be specified and unchanged within a patient to improve efficacy in clinical practice. RELEVANCE TO CLINICAL PRACTICE: The Edmonton Symptom Assessment System-revised or the European Organization for Research and Treatment of Cancer, Quality of Life Questionnaire Core 15 Palliative can be used for initial assessments of patients, but should not be compared or used interchangeably. It is vitally important to have individual follow-up for all patients who score an instrument.

Global cognitive factors modulate correlated response variability between V4 neurons.

Recent studies have shown that cognitive factors such as spatial and feature-based attention, learning, and task-switching can change the extent to which the trial-to-trial variability in the responses of neurons in sensory cortex is shared between pairs of neurons (for review, see Cohen and Kohn, 2011). Global cognitive factors related to concentration, motivation, effort, arousal, or alertness also affect performance on perceptual tasks and the responses of individual neurons in many cortical areas (Spitzer et al., 1988; Spitzer and Richmond, 1991; Motter, 1993; Bichot et al., 2001; Hasegawa et al., 2004; Boudreau et al., 2006; Niwa et al., 2012). The question of how global cognitive factors affect correlated response variability is important because these factors likely vary both across and within all psychophysical and physiological studies. Furthermore, global cognitive factors might provide a convenient platform for studying the neuronal mechanisms underlying how cognitive factors affect correlated variability because they can be manipulated easily without training complex perceptual tasks. We recorded simultaneously from groups of neurons in visual area V4 while rhesus monkeys performed a contrast discrimination task whose difficulty changed in blocks of trials. We found that correlated variability decreased when the task was more difficult, even when the visual stimuli were far outside the receptive fields of the recorded neurons. Our results suggest that studying global cognitive factors might provide a general framework for studying how cognitive factors affect the responses of neurons throughout sensory cortex.

Symptom profiles in children with advanced cancer: Patient, family caregiver, and oncologist ratings.

BACKGROUND: Systematic symptom assessment is not routinely performed in pediatric oncology. The objectives of the current study were to characterize the symptoms of pediatric oncology outpatients and evaluate agreement between patient and proxy reports and the association between children's ratings and oncologists' treatment recommendations. METHODS: Two versions of the pediatric Memorial Symptom Assessment Scale (pMSAS) were translated into Spanish. An age-appropriate and language-appropriate pMSAS was administered independently before visits to the oncologist to patients and family caregivers (caregivers) and after visits to consenting oncologists. Statistical analysis included Spearman correlation coefficients and weighted kappa values. RESULTS: English and Spanish results were similar and were combined. A total of 60 children and their caregivers completed the pMSAS. The children had a median age of 10 years (range, 7-18 years); approximately 62% were male and 33% were Spanish-speaking. Fourteen oncologists completed the pMSAS for 25 patients. Nine patients (15%) had no symptoms and 38 patients (63%) reported ≥2 symptoms. The most common symptoms were fatigue (12 patients; 40%) and itch (9 patients; 30%) for the younger children and pain (15 patients; 50%) and lack of energy (13 patients; 45%) among the older children. Total and subscale score agreement varied by proxy type and subscale, ranging from fair to good for most comparisons. Agreement for individual symptoms between the patient and proxy ranged from a kappa of -0.30 (95% confidence interval, -0.43 to -0.01) to 0.91 (95% confidence interval, 0.75 to 1.00). Three of 51 symptomatic patients (6%) had treatment recommendations documented in the electronic health record. CONCLUSIONS: Symptoms are common and cross several functional domains. Proxy and child reports are often not congruent, possibly explaining apparent undertreatment among this group of patients.

Implementing common data elements across studies to advance research.

Challenges arise in building the knowledge needed for evidence-based practice partially because obtaining clinical research data is expensive and complicated, and many studies have small sample sizes. Combining data from several studies may have the advantage of increasing the impact of the findings or expanding the population to which findings may be generalized. The use of common data elements will allow this combining and, in turn, create big data, which is an important approach that may accelerate knowledge development. This article discusses the philosophy of using common data elements across research studies and illustrates their use by the processes in a developmental center grant funded by the National Institutes of Health. The researchers identified a set of data elements and used them across several pilot studies. Issues that need to be considered in the adoption and implementation of common data elements across pilot studies include theoretical framework, purpose of the common measures, respondent burden, teamwork, managing large data sets, grant writing, and unintended consequences. We describe these challenges and solutions that can be implemented to manage them.

Effectiveness and safety of the awakening and breathing coordination, delirium monitoring/management, and early exercise/mobility bundle.

OBJECTIVE: The debilitating and persistent effects of ICU-acquired delirium and weakness warrant testing of prevention strategies. The purpose of this study was to evaluate the effectiveness and safety of implementing the Awakening and Breathing Coordination, Delirium monitoring/management, and Early exercise/mobility bundle into everyday practice. DESIGN: Eighteen-month, prospective, cohort, before-after study conducted between November 2010 and May 2012. SETTING: Five adult ICUs, one step-down unit, and one oncology/hematology special care unit located in a 624-bed tertiary medical center. PATIENTS: Two hundred ninety-six patients (146 prebundle and 150 postbundle implementation), who are 19 years old or older, managed by the institutions' medical or surgical critical care service. INTERVENTIONS: Awakening and Breathing Coordination, Delirium monitoring/management, and Early exercise/mobility bundle. MEASUREMENTS AND MAIN RESULTS: For mechanically ventilated patients (n = 187), we examined the association between bundle implementation and ventilator-free days. For all patients, we used regression models to quantify the relationship between Awakening and Breathing Coordination, Delirium monitoring/management, and Early exercise/mobility bundle implementation and the prevalence/duration of delirium and coma, early mobilization, mortality, time to discharge, and change in residence. Safety outcomes and bundle adherence were monitored. Patients in the postimplementation period spent three more days breathing without mechanical assistance than did those in the preimplementation period (median [interquartile range], 24 [7-26] vs 21 [0-25]; p = 0.04). After adjusting for age, sex, severity of illness, comorbidity, and mechanical ventilation status, patients managed with the Awakening and Breathing Coordination, Delirium monitoring/management, and Early exercise/mobility bundle experienced a near halving of the odds of delirium (odds ratio, 0.55; 95% CI, 0.33-0.93; p = 0.03) and increased odds of mobilizing out of bed at least once during an ICU stay (odds ratio, 2.11; 95% CI, 1.29-3.45; p = 0.003). No significant differences were noted in self-extubation or reintubation rates. CONCLUSIONS: Critically ill patients managed with the Awakening and Breathing Coordination, Delirium monitoring/management, and Early exercise/mobility bundle spent three more days breathing without assistance, experienced less delirium, and were more likely to be mobilized during their ICU stay than patients treated with usual care.

Smoking in young adult African Americans.

AIM: The aim of this study was to describe factors that influence decisions of young African Americans to start smoking. BACKGROUND: Young adult African Americans have a high risk for becoming regular smokers, but little is understood about their smoking. This knowledge is needed because understanding young adults' smokers will help develop effective tobacco cessation and prevention strategies. DESIGN: Qualitative study. METHOD: The study consisted of 22 in-depth interviews with African Americans between the ages of 19-25. Data were collected between 2009-2010. Smokers, former smokers and non-smokers were included. RESULTS/FINDINGS: Results indicated that smoking identity of young adults was influenced by their limited and discounted knowledge of health risks and the stigma associated with the type of tobacco smoked. The importance of cost was discussed as was the effect of smoking on relationships and vice versa. Marijuana was the primary reason they started smoking tobacco. Their transition into adulthood and views of smoking, adulthood and success all influenced smoking. Additionally, self-reflection on personal choices around smoking was important and may be useful in effective smoking cessation programmes for this group. CONCLUSION: Nurses are in an ideal position to promote effective smoking cessation in young adults. Direct, culturally relevant messages are needed that fit into the context of the young adults' lives by addressing concurrent use of marijuana, self-esteem and success in life.