Stress impacts prefrontal cortex (PFC) activity and modulates working memory performance. In a recent study, stimulating the dorsolateral PFC (dlPFC) using transcranial direct current stimulation (tDCS) interacted with social stress in modulating participants' working memory. More specifically, stress disrupted the enhancing effects of dlPFC tDCS on working memory performance.
View Article and Find Full Text PDFBackground: This investigation examines the clinical benefits of prefrontal cortex transcranial direct current stimulation (tDCS) treatment of working memory (WM) dysfunction in chronic schizophrenia patients.
Research Design And Methods: 34 schizophrenia (SZ) patients were evaluated at baseline, and 29 patients were randomly assigned to either active tDCS intervention or sham tDCS intervention. tDCS intervention applied 10 consecutive sessions (20 minutes, 2 mA, two sessions a day) over 5 days.
Early auditory processing (EAP) deficits have been consistently documented in individuals diagnosed with schizophrenia (SZ). However, a relationship between EAP and executive attention has not been confirmed in SZ versus healthy controls (HC). The current study aimed to demonstrate that unlike HC, in SZ patients, auditory change-detection event-related potentials (ERPs) are significantly associated with executive working memory (WM) functioning.
View Article and Find Full Text PDFRecent studies indicated that left dorsolateral prefrontal cortex (DLPFC) transcranial direct current stimulation (tDCS) may improve clinical status and cognitive functioning in schizophrenia patients. The current study examined the effects of left prefrontal anodal tDCS on symptom-severity and on working memory performance in schizophrenia (SZ) patients. We conducted a double-blind, randomized sham-controlled parallel-group trial.
View Article and Find Full Text PDFRecent findings suggest that electroencephalography (EEG) oscillations in the theta and alpha frequency-bands reflect synchronized interregional neuronal activity and are considered to reflect cognitive-control, and executive working memory mechanisms in humans. Above the age of 50 years, hypothesized pronounced alterations in alpha and theta-band power at resting or across different WM-functioning brain states may well be due to pre-dementia cognitive impairments, or increasing severity of age-related neurological disorders. Executive working memory (EWM) functioning was assessed in older-adult participants (54 to 83 years old) by obtaining their WM-related EEG oscillations and WM performance scores.
View Article and Find Full Text PDFJ Alzheimers Dis
September 2021
There is an urgent need in advanced dementia for evidence-based clinical prognostic predictors that could positively influence ethical decisions allowing health provider and family preparation for early mortality. Accordingly, the authors review and discuss the prognostic utility of clinical assessments and objective measures of pathological brain states in advanced dementia patients associated with accelerated mortality. Overall, due to the paucity of brain-activity and clinical-comorbidity predictors of survival in advanced dementia, authors outline the potential prognostic value of brain-state electroencephalography (EEG) measures and reliable clinical indicators for forecasting early mortality in advanced dementia patients.
View Article and Find Full Text PDF: The current investigation evaluated the sensitivity of neural-reactivity markers of awareness versus standard clinical assessments in predicting 1-year survival in nonresponsive-awake patients with disorders of consciousness (DOC). Pre-attentive auditory mismatch-negativity (MMN) event-related potentials (ERP's), globally induced electroencephalography (EEG) spectral power following verbal command, and clinical parameters were assessed. The study included 10 patients with DOC with mixed etiology and 10 healthy controls (HC) at baseline.
View Article and Find Full Text PDFIEEE J Transl Eng Health Med
May 2020
EEG-driven research is paramount in cognitive-neuropsychological studies, as it provides a non-invasive window to the underlying neural mechanisms of cognition and behavior. A myriad collection of software and hardware frameworks has been developed to alleviate some of the technical barriers involved in EEG-driven research. we propose an integrated development environment which encompasses the entire technical "data-collection pipeline" of cognitive-neuropsychological research, including experiment design, data acquisition, data exploration and analysis in a state-of-the-art user interface.
View Article and Find Full Text PDFCogn Affect Behav Neurosci
February 2020
Recent reviews of transcranial direct current stimulation (tDCS) show limited support for its initially cited enhancing effects on working memory (WM). They highlight the need for additional research, assessing the specific circumstances that optimize stimulation outcome. Social stress is an attractive candidate in this regard, as it affects WM and is mediated by prefrontal cortex activity; tDCS that targets these neuronal networks may, therefore, interact with social stress to affect WM.
View Article and Find Full Text PDFThe current clinical investigation examined high-definition transcranial direct current stimulation (HD-tDCS) as a focal, non-invasive, anti-epileptic treatment in a child with early-onset epileptic encephalopathy. We investigated the clinical impact of repetitive (20 daily sessions) cathode-centered 4 × 1 HD-tDCS (1 mA, 20 min, 4 mm ring radius) over the dominant seizure-generating cortical zone in a 40-month-old child suffering from a severe neonatal epileptic syndrome known as Ohtahara syndrome (OS). Seizures and epileptiform activity were monitored and quantified using video-EEG over multiple days of baseline, intervention, and post-intervention periods.
View Article and Find Full Text PDFThe aim of this study was to identify and characterise the association between the prevalence of pressure ulcers, spasticity levels, and advanced dementia in disable elderly patients. Data were obtained from the patient medical files. Patients were hospitalised in the geriatric skilled nursing department.
View Article and Find Full Text PDFPrimary Objective: Early onset epileptic encephalopathy is characterized by high daily seizure-frequency, multifocal epileptic discharges, severe psychomotor retardation, and death at infancy. Currently, there are no effective treatments to alleviate seizure frequency and high-voltage epileptic discharges in these catastrophic epilepsy cases. The current study examined the safety and feasibility of High-Definition transcranial direct current stimulation (HD-tDCS) in reducing epileptiform activity in a 30-month-old child suffering from early onset epileptic encephalopathy.
View Article and Find Full Text PDFFront Aging Neurosci
October 2017
In order to prevent the onset of vascular dementia (VaD) in aging individuals, it is critical to detect clinically relevant vascular and systemic pathophysiological changes to signal the onset of its preceding prodromal stages. Identifying behavioral and neurobiological markers that are highly sensitive to VaD classification vs. other dementias is likely to assist in developing novel preventive treatment strategies that could delay the onset of disruptive psychomotor symptoms, decrease hospitalizations, and increase the quality of life in clinically-high-risk aging individuals.
View Article and Find Full Text PDFJ Alzheimers Dis
February 2018
The current theoretical investigation aimed to explore common pathophysiological mechanisms underlying dementia and pressure ulcers (PU). Along with the increased longevity, especially in frail elderly patients, there is a higher rate of functional and cognitive impairment with dementia coinciding with immobility, which results in a higher rate of PU. Understanding common etiological paths resulting in pressure ulcers and dementia is likely to produce new treatment strategies that could lead to the prevention of comorbid complications.
View Article and Find Full Text PDFBackground/study Context: The mortality rates for many leading causes of death have declined over the past decade. Advanced dementia with comorbidities has steadily increased to become one of the leading causes of death in the elderly population. Therefore, this study examined the effect of pressure ulcers on the survival time of patients with advanced dementia and comorbidities.
View Article and Find Full Text PDFObjective: We intended to examine how theta-rhythm transcranial alternating current stimulation (tACS) (versus sham non-active stimulation) modulated associations between working memory accuracy and later retrospective self-evaluation scores.
Methods: Healthy participants were required to complete a verbal working memory task while receiving tACS bilaterally over the dorsolateral prefrontal cortex (DLPFC) versus sham DLPFC stimulation. After completion of the online and post-stimulation working memory tasks, participants were asked to rate the level of success-confidence on the two preceding working memory tasks.
Executive attention (EA) is a core-construct of working memory (WM) capacity. EA performance is directly related to dorsolateral prefrontal cortex (DLPFC) activation, a neural mechanism that is dysfunctional in schizophrenia. We examined the differences in particular types of EA failure in schizophrenia patients and healthy controls.
View Article and Find Full Text PDFBackground: Recent studies revealed that anodal transcranial direct current stimulation (tDCS) to the left dorsolateral prefrontal cortex (DLPFC) may improve verbal working memory (WM) performance in humans. In the present study, we evaluated executive attention, which is the core of WM capacity, considered to be significantly involved in tasks that require active maintenance of memory representations in interference-rich conditions, and is highly dependent on DLPFC function.
Objectives: We investigated verbal WM accuracy using a WM task that is highly sensitive to executive attention function.