Intermittent tACS during a visual task impacts neural oscillations and LZW complexity.

Little is known about how transcranial alternating current stimulation (tACS) interacts with brain activity. Here, we investigate the effects of tACS using an intermittent tACS-EEG protocol and use, in addition to classical metrics, Lempel-Ziv-Welch complexity (LZW) to characterize the interactions between task, endogenous and exogenous oscillations. In a cross-over study, EEG was recorded from thirty participants engaged in a change-of-speed detection task while receiving multichannel tACS over the visual cortex at 10 Hz, 70 Hz and a control condition. In each session, tACS was applied intermittently during 5 s events interleaved with EEG recordings over multiple trials. We found that, with respect to control, stimulation at 10 Hz ([Formula: see text]) enhanced both [Formula: see text] and [Formula: see text] power, [Formula: see text]-LZW complexity and [Formula: see text] but not [Formula: see text] phase locking value with respect to tACS onset ([Formula: see text]-PLV, [Formula: see text]-PLV), and increased reaction time (RT). [Formula: see text] increased RT with little impact on other metrics. As trials associated with larger [Formula: see text]-power (and lower [Formula: see text]-LZW) predicted shorter RT, we argue that [Formula: see text] produces a disruption of functionally relevant fast oscillations through an increase in [Formula: see text]-band power, slowing behavioural responses and increasing the complexity of gamma oscillations. Our study highlights the complex interaction between tACS and endogenous brain dynamics, and suggests the use of algorithmic complexity inspired metrics to characterize cortical dynamics in a behaviorally relevant timescale.

The INTERGROWTH-21st Project Neurodevelopment Package: a novel method for the multi-dimensional assessment of neurodevelopment in pre-school age children.

BACKGROUND: The International Fetal and Newborn Growth Consortium for the 21st Century (INTERGROWTH-21st) Project is a population-based, longitudinal study describing early growth and development in an optimally healthy cohort of 4607 mothers and newborns. At 24 months, children are assessed for neurodevelopmental outcomes with the INTERGROWTH-21st Neurodevelopment Package. This paper describes neurodevelopment tools for preschoolers and the systematic approach leading to the development of the Package. METHODS: An advisory panel shortlisted project-specific criteria (such as multi-dimensional assessments and suitability for international populations) to be fulfilled by a neurodevelopment instrument. A literature review of well-established tools for preschoolers revealed 47 candidates, none of which fulfilled all the project's criteria. A multi-dimensional assessment was, therefore, compiled using a package-based approach by: (i) categorizing desired outcomes into domains, (ii) devising domain-specific criteria for tool selection, and (iii) selecting the most appropriate measure for each domain. RESULTS: The Package measures vision (Cardiff tests); cortical auditory processing (auditory evoked potentials to a novelty oddball paradigm); and cognition, language skills, behavior, motor skills and attention (the INTERGROWTH-21st Neurodevelopment Assessment) in 35-45 minutes. Sleep-wake patterns (actigraphy) are also assessed. Tablet-based applications with integrated quality checks and automated, wireless electroencephalography make the Package easy to administer in the field by non-specialist staff. The Package is in use in Brazil, India, Italy, Kenya and the United Kingdom. CONCLUSIONS: The INTERGROWTH-21st Neurodevelopment Package is a multi-dimensional instrument measuring early child development (ECD). Its developmental approach may be useful to those involved in large-scale ECD research and surveillance efforts.

AsTeRICS: a new flexible solution for people with motor disabilities in upper limbs and its implication for rehabilitation procedures.

PURPOSE: To present the AsTeRICS construction set, and examine different combinations of sensors installed in the platform and how users interact with them. METHOD: Nearly 50 participants from Austria, Poland and Spain were included in the study. They had a heterogeneous range of diagnoses, but as a common feature all of them experienced motor limitations in their upper limbs. The study included a 1 h session with each participant where the user interacted with a personalized combination of sensors, based on a previous assessment on their motor capabilities performed by healthcare professionals. The sensors worked as substitutes for a standard QWERTY keyboard and a standard mouse. Semi-structured interviews were conducted to obtain participants' opinions. All collected data were analyzed based on the qualitative methodology. RESULTS: The findings illustrated that AsTeRICS is a flexible platform whose sensors can adapt to different degrees of users' motor capabilities, thus facilitating in most cases the interaction of the participants with a common computer. CONCLUSION: AsTeRICS platform can improve the interaction between people with mobility limitations and computers. It can provide access to new technologies and become a promising tool that can be integrated in physical rehabilitation programs for people with motor disabilities in their upper limbs. IMPLICATIONS FOR REHABILITATION: The AsTeRICS platform offers an interesting tool to interface and support the computerized rehabilitation program of the patients. Due to AsTeRICS platform high usability features, family and rehabilitation professionals can learn how to use the AsTeRICS platform quickly fostering the key role of their involvement on patients' rehabilitation. AsTeRICS is a flexible, extendable, adaptable and affordable technology adapted for using computer, environmental control, mobile phone, rehabilitation programs and mechatronic systems. AsTeRICS makes possible an easy reconfiguration and integration of new functionalities, such as biofeedback rehabilitation, without major changes in the system.