Attentional filtering of visual information by neuronal ensembles in the primate lateral prefrontal cortex.

The activity of neurons in the primate lateral prefrontal cortex (LPFC) is strongly modulated by visual attention. Such a modulation has mostly been documented by averaging the activity of independently recorded neurons over repeated experimental trials. However, in realistic settings, ensembles of simultaneously active LPFC neurons must generate attentional signals on a single-trial basis, despite the individual and correlated variability of neuronal responses. Whether, under these circumstances, the LPFC can reliably generate attentional signals is unclear. Here, we show that the simultaneous activity of neuronal ensembles in the primate LPFC can be reliably decoded to predict the allocation of attention on a single-trial basis. Decoding was sensitive to the noise correlation structure of the ensembles. Additionally, it was resilient to distractors, predictive of behavior, and stable over weeks. Thus, LPFC neuronal ensemble activity can reliably encode attention within behavioral time frames, despite the noisy and correlated nature of neuronal activity

The effects of methylphenidate (Ritalin) on the neurophysiology of the monkey caudal prefrontal cortex

© 2019 Tremblay et al. Methylphenidate (MPH), commonly known as Ritalin, is the most widely prescribed drug worldwide to treat patients with attention deficit disorders. Although MPH is thought to modulate catecholamine neurotransmission in the brain, it remains unclear how these neurochemical effects influence neuronal activity and lead to attentional enhancements. Studies in rodents overwhelmingly point to the lateral prefrontal cortex (LPFC) as a main site of action of MPH. To understand the mechanism of action of MPH in a primate brain, we recorded the responses of neuronal populations using chronic multielectrode arrays implanted in the caudal LPFC of two macaque monkeys while the animals performed an attention task (N 2811 neuronal recordings). Over different recording sessions (N 55), we orally administered either various doses of MPH or a placebo to the animals. Behavioral analyses revealed positive effects of MPH on task performance at specific doses. However, analyses of individual neurons activity, noise correlations, and neuronal ensemble activity using machine learning algorithms revealed no effects of MPH. Our results suggest that the positive behavioral effects of MPH observed in primates (including humans) may not be mediated by changes in the activity of caudal LPFC neurons. MPH may enhance cognitive performance by modulating neuronal activity in other regions of the attentional network in the primate brain

Hydrogen Balmer Line Broadening in Solar and Stellar Flares

The broadening of the hydrogen lines during flares is thought to result from increased charge (electron, proton) density in the flare chromosphere. However, disagreements between theory and modeling prescriptions have precluded an accurate diagnostic of the degree of ionization and compression resulting from flare heating in the chromosphere. To resolve this issue, we have incorporated the unified theory of electric pressure broadening of the hydrogen lines into the non-LTE radiative transfer code RH. This broadening prescription produces a much more realistic spectrum of the quiescent, A0 star Vega compared to the analytic approximations used as a damping parameter in the Voigt profiles. We test recent radiative-hydrodynamic (RHD) simulations of the atmospheric response to high nonthermal electron beam fluxes with the new broadening prescription and find that the Balmer lines are over-broadened at the densest times in the simulations. Adding many simultaneously heated and cooling model loops as a "multithread" model improves the agreement with the observations. We revisit the three-component phenomenological flare model of the YZ CMi Megaflare using recent and new RHD models. The evolution of the broadening, line flux ratios, and continuum flux ratios are well-reproduced by a multithread model with high-flux nonthermal electron beam heating, an extended decay phase model, and a "hot spot" atmosphere heated by an ultrarelativistic electron beam with reasonable filling factors: 0.1%, 1%, and 0.1% of the visible stellar hemisphere, respectively. The new modeling motivates future work to understand the origin of the extended gradual phase emission.Comment: 31 pages, 13 figures, 2 tables, accepted for publication in the Astrophysical Journa

Study protocol: The Adherence and Intensification of Medications (AIM) study - a cluster randomized controlled effectiveness study

Abstract Background Many patients with diabetes have poor blood pressure (BP) control. Pharmacological therapy is the cornerstone of effective BP treatment, yet there are high rates both of poor medication adherence and failure to intensify medications. Successful medication management requires an effective partnership between providers who initiate and increase doses of effective medications and patients who adhere to the regimen. Methods In this cluster-randomized controlled effectiveness study, primary care teams within sites were randomized to a program led by a clinical pharmacist trained in motivational interviewing-based behavioral counseling approaches and authorized to make BP medication changes or to usual care. This study involved the collection of data during a 14-month intervention period in three Department of Veterans Affairs facilities and two Kaiser Permanente Northern California facilities. The clinical pharmacist was supported by clinical information systems that enabled proactive identification of, and outreach to, eligible patients identified on the basis of poor BP control and either medication refill gaps or lack of recent medication intensification. The primary outcome is the relative change in systolic blood pressure (SBP) measurements over time. Secondary outcomes are changes in Hemoglobin A1c, low-density lipoprotein cholesterol (LDL), medication adherence determined from pharmacy refill data, and medication intensification rates. Discussion Integration of the three intervention elements - proactive identification, adherence counseling and medication intensification - is essential to achieve optimal levels of control for high-risk patients. Testing the effectiveness of this intervention at the team level allows us to study the program as it would typically be implemented within a clinic setting, including how it integrates with other elements of care. Trial Registration The ClinicalTrials.gov registration number is NCT00495794.http://deepblue.lib.umich.edu/bitstream/2027.42/78258/1/1745-6215-11-95.xmlhttp://deepblue.lib.umich.edu/bitstream/2027.42/78258/2/1745-6215-11-95.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/78258/3/1745-6215-11-95-S1.DOCPeer Reviewe

Procedural learning in Tourette syndrome, ADHD, and comorbid Tourette-ADHD: Evidence from a probabilistic sequence learning task

Procedural memory, which is rooted in the basal ganglia, plays an important role in the implicit learning of motor and cognitive skills. Few studies have examined procedural learning in either Tourette syndrome (TS) or Attention Deficit Hyperactivity Disorder (ADHD), despite basal ganglia abnormalities in both of these neurodevelopmental disorders. We aimed to assess procedural learning in children with TS (n = 13), ADHD (n = 22), and comorbid TS-ADHD (n = 20), as well as in typically developing children (n = 21). Procedural learning was measured with a well-studied implicit probabilistic sequence learning task, the alternating serial reaction time task. All four groups showed evidence of sequence learning, and moreover did not differ from each other in sequence learning. This result, from the first study to examine procedural memory across TS, ADHD and comorbid TS-ADHD, is consistent with previous findings of intact procedural learning of sequences in both TS and ADHD. In contrast, some studies have found impaired procedural learning of non-sequential probabilistic categories in TS. This suggests that sequence learning may be spared in TS and ADHD, while at least some other forms of learning in procedural memory are impaired, at least in TS. Our findings indicate that disorders associated with basal ganglia abnormalities do not necessarily show procedural learning deficits, and provide a possible path for more effective diagnostic tools, and educational and training programs

In sight but out of mind

No Abstract.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/69158/1/649_ftp.pd

Engaging family supporters of adult patients with diabetes to improve clinical and patient-centered outcomes: study protocol for a randomized controlled trial

Abstract Background Most adults with diabetes who are at high risk for complications have family or friends who are involved in their medical and self-care (“family supporters”). These family supporters are an important resource who could be leveraged to improve patients’ engagement in their care and patient health outcomes. However, healthcare teams lack structured and feasible approaches to effectively engage family supporters in patient self-management support. This trial tests a strategy to strengthen the capacity of family supporters to help adults with high-risk diabetes engage in healthcare, successfully enact care plans, and lower risk of diabetes complications. Methods/design We will conduct a randomized trial evaluating the CO-IMPACT (Caring Others Increasing EnageMent in Patient Aligned Care Teams) intervention. Two hunded forty adults with diabetes who are at high risk for diabetes complications due to poor glycemic control or high blood pressure will be randomized, along with a family supporter (living either with the patient or remotely), to CO-IMPACT or enhanced usual primary care for 12 months. CO-IMPACT provides patient-supporter dyads: it provides one coaching session addressing supporter techniques for helping patients with behavior change motivation, action planning, and proactive communication with healthcare providers; biweekly automated phone calls to prompt dyad action on new patient health concerns; phone calls to prompt preparation for patients’ primary care visits; and primary care visit summaries sent to both patient and supporter. Primary outcomes are changes in patient activation, as measured by the Patient Activation Measure-13, and change in 5-year cardiac event risk, as measured by the United Kingdom Prospective Diabetes Study cardiac risk score for people with diabetes. Secondary outcomes include patients’ diabetes self-management behaviors, diabetes distress, and glycemic and blood pressure control. Measures among supporters will include use of effective support techniques, burden, and distress about patient’s diabetes care. Discussion If effective in improving patient activation and diabetes management, CO-IMPACT will provide healthcare teams with evidence-based tools and techniques to engage patients’ available family or friends in supporting patient self-management, even if they live remotely. The core skills addressed by CO-IMPACT can be used by patients and their supporters over time to respond to changing patient health needs and priorities. Trial registration ClinicalTrials.gov, NCT02328326 . Registered on 31 December 2014.https://deepblue.lib.umich.edu/bitstream/2027.42/145179/1/13063_2018_Article_2785.pd

Engaging family supporters of adult patients with diabetes to improve clinical and patient-centered outcomes: study protocol for a randomized controlled trial

Abstract Background Most adults with diabetes who are at high risk for complications have family or friends who are involved in their medical and self-care (“family supporters”). These family supporters are an important resource who could be leveraged to improve patients’ engagement in their care and patient health outcomes. However, healthcare teams lack structured and feasible approaches to effectively engage family supporters in patient self-management support. This trial tests a strategy to strengthen the capacity of family supporters to help adults with high-risk diabetes engage in healthcare, successfully enact care plans, and lower risk of diabetes complications. Methods/design We will conduct a randomized trial evaluating the CO-IMPACT (Caring Others Increasing EnageMent in Patient Aligned Care Teams) intervention. Two hunded forty adults with diabetes who are at high risk for diabetes complications due to poor glycemic control or high blood pressure will be randomized, along with a family supporter (living either with the patient or remotely), to CO-IMPACT or enhanced usual primary care for 12 months. CO-IMPACT provides patient-supporter dyads: it provides one coaching session addressing supporter techniques for helping patients with behavior change motivation, action planning, and proactive communication with healthcare providers; biweekly automated phone calls to prompt dyad action on new patient health concerns; phone calls to prompt preparation for patients’ primary care visits; and primary care visit summaries sent to both patient and supporter. Primary outcomes are changes in patient activation, as measured by the Patient Activation Measure-13, and change in 5-year cardiac event risk, as measured by the United Kingdom Prospective Diabetes Study cardiac risk score for people with diabetes. Secondary outcomes include patients’ diabetes self-management behaviors, diabetes distress, and glycemic and blood pressure control. Measures among supporters will include use of effective support techniques, burden, and distress about patient’s diabetes care. Discussion If effective in improving patient activation and diabetes management, CO-IMPACT will provide healthcare teams with evidence-based tools and techniques to engage patients’ available family or friends in supporting patient self-management, even if they live remotely. The core skills addressed by CO-IMPACT can be used by patients and their supporters over time to respond to changing patient health needs and priorities. Trial registration ClinicalTrials.gov, NCT02328326 . Registered on 31 December 2014.https://deepblue.lib.umich.edu/bitstream/2027.42/145179/1/13063_2018_Article_2785.pd