Search results for "AIV"
showing 10 items of 375 documents
Validation of a New Cognitive Screening Method for Stroke Patients
2019
Objective. Two million adults under fifty years of age have a cerebral stroke every year worldwide. Neuropsychological assessment is the best way to identify poststroke cognitive dysfunction, but it is often time-consuming and can be tiring for the patient, and hospitals vary in their availability of neuropsychological expertise. A valid and reliable cognitive screening method could be advantageous in identifying patients who need comprehensive neuropsychological examination. Our purpose in this study was to validate a newly developed cognitive screening method as an identifier of cognitive dysfunction after stroke in working-aged patients. Methods. We analyzed new cognitive screening metho…
The effect of alertness and attention on the modulation of the beta rhythm to tactile stimulation
2021
Abstract Beta rhythm modulation has been used as a biomarker to reflect the functional state of the sensorimotor cortex in both healthy subjects and patients. Here, the effect of reduced alertness and active attention to the stimulus on beta rhythm modulation was investigated. Beta rhythm modulation to tactile stimulation of the index finger was recorded simultaneously with MEG and EEG in 23 healthy subjects (mean 23, range 19–35 years). The temporal spectral evolution method was used to obtain the peak amplitudes of beta suppression and rebound in three different conditions (neutral, snooze, and attention). Neither snooze nor attention to the stimulus affected significantly the strength of…
Hippocampal ripple-contingent training accelerates trace eyeblink conditioning and retards extinction in rabbits.
2010
There are at least two distinct oscillatory states of the hippocampus that are related to distinct behavioral patterns. Theta (4–12 Hz) oscillation has been suggested to indicate selective attention during which the animal concentrates on some features of the environment while suppressing reactivity to others. In contrast, sharp-wave ripples (∼200 Hz) can be seen in a state in which the hippocampus is at its most responsive to any kind of afferent stimulation. In addition, external stimulation tends to evoke and reset theta oscillation, the phase of which has been shown to modulate synaptic plasticity in the hippocampus. Theoretically, training on a hippocampus-dependent learning task conti…
Lysosomal Signaling Licenses Embryonic Stem Cell Differentiation via Inactivation of Tfe3
2019
International audience; Self-renewal and differentiation of pluripotent murine embryonic stem cells (ESCs) is regulated by extrinsic signaling pathways. It is less clear whether cellular metabolism instructs developmental progression. In an unbiased genome-wide CRISPR/Cas9 screen, we identified components of a conserved amino-acid-sensing pathway as critical drivers of ESC differentiation. Functional analysis revealed that lysosome activity, the Ragulator protein complex, and the tumor-suppressor protein Folliculin enable the Rag GTPases C and D to bind and seclude the bHLH transcription factor Tfe3 in the cytoplasm. In contrast, ectopic nuclear Tfe3 represses specific developmental and met…
Event-related potentials to task-irrelevant sad faces as a state marker of depression
2018
Negative bias in face processing has been demonstrated in depression, but there are no longitudinal investigations of negative bias in symptom reduction. We recorded event-related potentials (P1 and N170) to task-irrelevant facial expressions in depressed participants who were later provided with a psychological intervention and in never depressed control participants. Follow-up measurements were conducted for the depressed group two and 39 months later. Negative bias was found specifically in the depression group, and was demonstrated as enlarged P1 amplitude to sad faces, which normalized in the follow-up measurements when the participants had fewer symptoms. Because the P1 amplitude reco…
Children show hemispheric differences in the basic auditory response properties
2019
Auditory cortex in each hemisphere shows preference to sounds from the opposite hemifield in the auditory space. Besides this contralateral dominance, the auditory cortex shows functional and structural lateralization, presumably influencing the features of subsequent auditory processing. Children have been shown to differ from adults in the hemispheric balance of activation in higher-order auditory based tasks. We studied, first, whether the contralateral dominance can be detected in 7- to 8-year-old children and, second, whether the response properties of auditory cortex in children differ between hemispheres. Magnetoencephalography (MEG) responses to simple tones revealed adult-like cont…
Priming the Motor Cortex With Anodal Transcranial Direct Current Stimulation Affects the Acute Inhibitory Corticospinal Responses to Strength Trainin…
2019
Frazer, AK, Howatson, G, Ahtiainen, JP, Avela, J, Rantalainen, T, and Kidgell, DJ. Priming the motor cortex with anodal transcranial direct current stimulation affects the acute inhibitory corticospinal responses to strength training. J Strength Cond Res 33(2): 307-317, 2019-Synaptic plasticity in the motor cortex (M1) is associated with strength training (ST) and can be modified by transcranial direct current stimulation (tDCS). The M1 responses to ST increase when anodal tDCS is applied during training due to gating. An additional approach to improve the M1 responses to ST, which has not been explored, is to use anodal tDCS to prime the M1 before a bout of ST. We examined the priming effe…
Longitudinal interactions between brain and cognitive measures on reading development from 6 months to 14 years
2017
Dyslexia is a neurobiological disorder impairing learning to read. Brain responses of infants at genetic risk for dyslexia are abnormal already at birth, and associations from infant speech perception to preschool cognitive skills and reading in early school years have been documented, but there are no studies showing predicting power until adolescence. Here we show that in at-risk infants, brain activation to pseudowords at left hemisphere predicts 44% of reading speed at 14 years, and even improves the prediction after taking into account neurocognitive preschool measures of letter naming, phonology, and verbal short-term memory. The association between infant brain responses and reading …
Maturation changes the excitability and effective connectivity of the frontal lobe : A developmental TMS-EEG study
2019
The combination of transcranial magnetic stimulation with simultaneous electroencephalography (TMS–EEG) offers direct neurophysiological insight into excitability and connectivity within neural circuits. However, there have been few developmental TMS–EEG studies to date, and they all have focused on primary motor cortex stimulation. In the present study, we used navigated high‐density TMS–EEG to investigate the maturation of the superior frontal cortex (dorsal premotor cortex [PMd]), which is involved in a broad range of motor and cognitive functions known to develop with age. We demonstrated that reactivity to frontal cortex TMS decreases with development. We also showed that although fron…
Condition and Sperm Characteristics of Perch Perca fluviatilis inhabiting Boreal Lakes Receiving Metal Mining Effluents.
2020
AbstractOne of the world’s largest, but low-grade, sulfide nickel deposits in northeastern Finland has been exploited by a bioheapleaching technology since 2008. Bioheapleaching is a relatively new, cost-effective technology, but humid climate, e.g., in boreal temperate environments, causes challenges to the management of the water balance in the ore heaps with wide catchment area, and the mining effluents have caused substantial metal and salting contamination of the receiving waterbodies. In our study, the impacts of metal-extracting bioheapleaching mine effluents on muscle and liver element concentrations, body condition, liver and testes mass, and sperm count and motility of male perch …