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In rat barrel cortex, evoked potentials (EPs) to vibrissa stimulation can be divided into two distinct classes according to the relative contribution of their principal components. Our experiments support the notion that these components can be attributed to activation of two pyramidal cell populations: supra- and infragranular. With well-habituated stimuli EPs are dominated by a component related to the supragranular cells (class 1). However, the first reinforcement of vibrissa stimulation in the classical aversive paradigm favours the appearance of EPs dominated by a component characteristic of infragranular cells which matches with activation in the surround zone of the barrel field (class 2). Similar dynamic changes of the relative occurrence of the two EP classes follow other aversive stimuli, including pressing the animal’s ear and restraining a whisker. We hypothesize that neuromodulatory action elicited by contextual stimulation activates all neurons in the principal barrel column, including those providing an output to the surrounding barrels. In the classical conditioning paradigm this mechanism may lead to experience-dependent changes within the intracortical network. [ABSTRACT FROM AUTHOR]

Alterations in functional connectivity (FC) have been observed in individuals with Alzheimer's disease (AD) with elevated amyloid (Aβ) and tau. However, it is not yet known whether directed FC is already influenced by Aβ and tau load in cognitively healthy (CH) individuals. A 21-channel electroencephalogram (EEG) was used from 46 CHs classified based on cerebrospinal fluid (CSF) Aβ tau ratio: pathological (CH-PAT) or normal (CH-NAT). Directed FC was estimated with Partial Directed Coherence in frontal, temporal, parietal, central, and occipital regions. We also examined the correlations between directed FC and various functional metrics, including neuropsychology, cognitive reserve, MRI volumetrics, and heart rate variability between both groups. Compared to CH-NATs, the CH-PATs showed decreased FC from the temporal regions, indicating a loss of relative functional importance of the temporal regions. In addition, frontal regions showed enhanced FC in the CH-PATs compared to CH-NATs, suggesting neural compensation for the damage caused by the pathology. Moreover, CH-PATs showed greater FC in the frontal and occipital regions than CH-NATs. Our findings provide a useful and non-invasive method for EEG-based analysis to identify alterations in brain connectivity in CHs with a pathological versus normal CSF Aβ/tau. This study reveals disrupted brain functional connectivity as an early biomarker in cognitively healthy individuals with pathological CSF amyloid/tau, aiding early Alzheimer's detection. [ABSTRACT FROM AUTHOR]

Objectives: Mindfulness-Based Stress Reduction (MBSR) has been shown to decrease general feelings of distress. It is not known to what extent such beneficial effects are associated with attenuation of physiological responses to challenging psychological situations. The aim of the present study was to examine potential associations between general decreases in subjective distress and changes in acute cardiac and cortical responses during recall of a recent stressful episode between pre- and post-MBSR. Method: Fifty-eight MBSR participants (77.6% female, mean age 43.8 years, SD = 13.1) took part in a laboratory examination before and after MBSR. Measurements of the electrocardiogram (ECG) and electroencephalogram (EEG) were performed during the whole protocol including the stress recall task. Results: The MBSR group showed overall decreases in general negative affect and an increase in heart rate variability from pre- to post-intervention. Out of six physiological outcomes (heart rate, heart rate variability, theta, alpha, beta, and gamma power at Fz), only a decreased response of gamma power during the stress task was significant. The subjective and physiological changes were unrelated. Conclusions: The present results suggest that the favourable effects of MBSR on general stress reduction may not be clearly reflected in cortical electrical wave activity or vagal cardiac response during recall of a recent stressful episode. The few changes found in cardiac and cortical activity may be due to either effects independent of general subjective feelings or independent of the intervention altogether. Preregistration: The study is not preregistered. [ABSTRACT FROM AUTHOR]

Studying deception is vital for understanding decision-making and social dynamics. Recent EEG research has deepened insights into the brain mechanisms behind deception. Standard methods in this field often rely on memory, are vulnerable to countermeasures, yield false positives, and lack real-world relevance. Here, we present a comprehensive dataset from an EEG-monitored competitive, two-player card game designed to elicit authentic deception behavior. Our extensive dataset contains EEG data from 12 pairs (N = 24 participants with role switching), controlled for age, gender, and risk-taking, with detailed labels and annotations. The dataset combines standard event-related potential and microstate analyses with state-of-the-art decoding approaches of four scenarios: spontaneous/instructed truth-telling and lying. This demonstrates game-based methods' efficacy in studying deception and sets a benchmark for future research. Overall, our dataset represents a unique resource with applications in cognitive neuroscience and related fields for studying deception, competitive behavior, decision-making, inter-brain synchrony, and benchmarking of decoding frameworks in a difficult, high-level cognitive task. [ABSTRACT FROM AUTHOR]

Interdisciplinary approaches are needed to understand the relationship between genetic factors and brain structure and function. Here we describe a database that includes genetic data on apolipoprotein E (APOE) and phosphatidylinositol binding clathrin assembly protein (PICALM) genes, both of which are known to increase the risk of late-onset Alzheimer's disease, paired with psychometric (memory, intelligence, mood, personality, stress coping strategies), basic demographic and health data on a cohort of 192 healthy middle-aged (50–63) individuals. Part of the database (~79 participants) also includes blood tests (blood counts, lipid profile, HSV virus) and functional neuroimaging data (EEG/fMRI) recorded with a resting-state protocol (eyes open and eyes closed) and two cognitive tasks (multi-source interference task, MSIT; and Sternberg's memory task). The data were validated and showed overall good quality. This open-science dataset is well suited not only for research relating to susceptibility to Alzheimer's disease but also for more general questions on brain aging or can be used as part of meta-analytical multi-disciplinary projects. [ABSTRACT FROM AUTHOR]

We investigated the participation of the nucleus of the tractus solitarius (NTS) in tonic‒clonic seizures and postictal antinociception control mediated by NMDA receptors, the role of NTS GABAergic interneurons and noradrenergic pathways from the locus coeruleus (LC) in these phenomena. The NTS-lateral nucleus reticularis paragigantocellularis (lPGi)-LC pathway was studied by evaluating neural tract tracer deposits in the lPGi. NMDA and GABAergic receptors agonists and antagonists were microinjected into the NTS, followed by pharmacologically induced seizures. The effects of LC neurotoxic lesions caused by DSP-4, followed by NTS-NMDA receptor activation, on both tonic‒clonic seizures and postictal antinociception were also investigated. The NTS is connected to lPGi neurons that send outputs to the LC. Glutamatergic vesicles were found on dendrites and perikarya of GABAergic interneurons in the NTS. Both tonic‒clonic seizures and postictal antinociception are partially dependent on glutamatergic-mediated neurotransmission in the NTS of seizing rats in addition to the integrity of the noradrenergic system since NMDA receptor blockade in the NTS and intrathecal administration of DSP-4 decrease the postictal antinociception. The GABAA receptor activation in the NTS decreases both seizure severity and postictal antinociception. These findings suggest that glutamatergic inputs to NTS-GABAergic interneurons, in addition to ascending and descending noradrenergic pathways from the LC, are critical for the control of both seizures and postictal antinociception. [ABSTRACT FROM AUTHOR]

Testing the components of emotional intelligence (EI) in patients with coronary heart disease (CHD) showed that they are more likely to react to emotionally significant situations than to express their emotions. The most pronounced influence on the frequency-spatial organization of brain activity, mainly in the θ1-, α2- and β1-ranges, is induced by such EI components as the expression of positive emotions, the use of emotions in decision-making, and empathy. An increase in self-assessment of positive expression is associated with an increase in the power of the β1-rhythm in the parieto-occipital cortex with the dominance of the left hemisphere and an increase in θ1 not only in these areas, but also in the posterofrontal cortical sites. The increase in empathy is accompanied by a decrease in the power of the β1-rhythm, mainly in the temporal cortex of the left hemisphere. Gender differences were found in the association of self-assessment of negative expression and the power of θ- and β-oscillations with greater involvement of the left frontal areas in women. The identified features of the relationship between EI and EEG parameters may be a consequence of the reorganization of cortical activity in patients with coronary heart disease, which develops as a result of chronic cerebral ischemia. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the effect of neurofeedback training on the executive control network of attention and dart-throwing skill performance in individuals with trait anxiety. Twenty girls (24.65 2.83 years) participated in this study. They were divided into neurofeedback and control training groups. All participants practiced 14 sessions. The neurofeedback group performed neurofeedback training (increasing SMR wave, decreasing theta, and increasing alpha) and dart-throwing exercise, and the control group only completed the dart-throwing exercise. The post-test, including Attentional Networks Test (ANT) and dart-throwing, was conducted 48 h after the last training session. The results revealed a significant difference in the performance of the executive control network and dart-throwing skill between the neurofeedback and the control training group. In general, these findings support the effect of neurofeedback training on the neural mechanisms of the executive control network of attention, and performance in dart-throwing skill improves by improving attentional performance processes. [ABSTRACT FROM AUTHOR]

Paranormal believers' thinking is frequently biased by intuitive beliefs. Lack of inhibition of these tempting beliefs is considered a key element in paranormal believers' thinking. However, the brain activity related to inhibitory control in paranormal believers is poorly understood. We examined EEG activities at resting state in alpha, beta, and gamma bands with inhibitory control in paranormal believers and skeptics. The present study shows that paranormal belief is related to the reduced power of the alpha, beta, and gamma frequency bands, and reduced inhibitory control. This study may contribute to understanding the differences between believers and skeptics in brain activity related to inhibitory control in paranormal believers. [ABSTRACT FROM AUTHOR]

Recently, there has been considerable interest in the mechanism of cooperation between the frontoparietal system and the default system, since their "pre-tuning" at rest and the subsequent functional interaction dynamics is associated with individual variety of strategies for task performance upon creativity testing. To study the EEG correlates of these strategies, regional features of resting state ∆- and β-oscillations were analyzed and compared with the results from preliminary creativity and intelligence testing in 37 university students (18 ± 1.1 years; 27 females and 10 males). The response originality indices in the creativity tests were calculated using databases previously designed by the authors for the "Circles," "Incomplete figures," and "Unusual use of ordinary objects" subtests and an expert assessment of originality of the sentences composed of words belonging to different semantic categories. The intelligence verbal and figurative components were assessed according to the Amthauer intelligence structure subtests. Using cluster analysis of the listed creativity and intelligence indices, two groups of study participants were identified. One of the groups (GRCIQ) was characterized by a combination of higher values of intelligence and originality of responses in the tasks that required the rejection of stereotypical ideas upon limited search time, and the other group (GRC), characterized by relatively lower intelligence, but high originality of solving the problem upon the creativity testing with a variety of stimuli and without time limits. These two groups differed in regional organization of the ∆- and β2-rhythm power and in the rhythm correlation patterns. In particular, GRCIQ is characterized by generalized high-frequency β-activity and its correlation with low-frequency biopotentials in the frontal cortex, while GRC is characterized by cortical mosaic of the β2-activity with its diffusely distributed correlations with the ∆-rhythm with the exception of the anterior frontal areas. The discovered effects can be considered as a pre-tuning to the "intelligent" search strategy for an original solution in the conditions of resistance to fixation on a stereotyped idea in GRCIQ or to solutions based on spontaneous search for distant associations in GRC. [ABSTRACT FROM AUTHOR]

Paranormal believers' thinking is frequently biased by intuitive beliefs. Lack of inhibition of these tempting beliefs is considered a key element in paranormal believers' thinking. However, the brain activity related to inhibitory control in paranormal believers is poorly understood. We examined EEG activities at resting state in alpha, beta, and gamma bands with inhibitory control in paranormal believers and skeptics. The present study shows that paranormal belief is related to the reduced power of the alpha, beta, and gamma frequency bands, and reduced inhibitory control. This study may contribute to understanding the differences between believers and skeptics in brain activity related to inhibitory control in paranormal believers. [ABSTRACT FROM AUTHOR]

Research investigating the effects and underlying mechanisms of mindfulness on cognitive functioning has accelerated exponentially over the past two decades. Despite the rapid growth of the literature and its influential role in garnering public interest in mindfulness, inconsistent methods in defining and measuring mindfulness have yielded variable findings, which contribute to the overall dearth of clear generalizable conclusions. The focus of this article is to address the lack of cohesion in the collective methodologies used in this domain by providing a new perspective grounded in classic cognitive and experimental psychology principles. We leverage the concept of converging operations to demonstrate how seemingly disparate research strategies can be integrated towards a more unified and systematic approach. An organizing taxonomic framework is described to provide useful structure in how mindfulness can be operationalized, measured, and investigated. We illustrate the rationale and core organizing principles of the framework through a selective review of studies on mindfulness and cognitive control. We then demonstrate the utility of the approach by showing how it can be applied to synthesize extant methodologies and guide the development of future research. Specific suggestions and examples pertaining to experimental design and statistical analysis are provided. [ABSTRACT FROM AUTHOR]

As attention to deep learning techniques has grown, many researchers have attempted to develop ready-to-go brain-computer interfaces (BCIs) that include automatic processing pipelines. However, to do so, a large and clear dataset is essential to increase the model's reliability and performance. Accordingly, our electroencephalogram (EEG) dataset for rapid serial visual representation (RSVP) and P300 speller may contribute to increasing such BCI research. We validated our dataset with respect to features and accuracy. For the RSVP, the participants (N = 50) achieved about 92% mean target detection accuracy. At the feature level, we observed notable ERPs (at 315 ms in the RSVP; at 262 ms in the P300 speller) during target events compared to non-target events. Regarding P300 speller performance, the participants (N = 55) achieved about 92% mean accuracy. In addition, P300 speller performance over trial repetitions up to 15 was explored. The presented dataset could potentially improve P300 speller applications. Further, it may be used to evaluate feature extraction and classification algorithm effectively, such as for cross-subjects/cross-datasets, and even for the cross-paradigm BCI model. Measurement(s) Electroencephalography Technology Type(s) electroencephalography (EEG) Sample Characteristic - Organism Homo sapiens [ABSTRACT FROM AUTHOR]

With increasing life expectancy and active aging, it becomes crucial to investigate methods which could compensate for generally detected cognitive aging processes. A promising candidate is adaptive cognitive training, during which task difficulty is adjusted to the participants' performance level to enhance the training and potential transfer effects. Measuring intrinsic brain activity is suitable for detecting possible distributed training-effects since resting-state dynamics are linked to the brain's functional flexibility and the effectiveness of different cognitive processes. Therefore, we investigated if adaptive task-switching training could modulate resting-state neural dynamics in younger (18–25 years) and older (60–75 years) adults (79 people altogether). We examined spectral power density on resting-state EEG data for measuring oscillatory activity, and multiscale entropy for detecting intrinsic neural complexity. Decreased coarse timescale entropy and lower frequency band power as well as increased fine timescale entropy and higher frequency band power revealed a shift from more global to local information processing with aging before training. However, cognitive training modulated these age-group differences, as coarse timescale entropy and lower frequency band power increased from pre- to post-training in the old-training group. Overall, our results suggest that cognitive training can modulate neural dynamics even when measured outside of the trained task. [ABSTRACT FROM AUTHOR]

The human mu rhythm has been suggested to represent an important function in information processing. Rodent homologue rhythms have been assumed though no study has investigated them from the cognitive aspect yet. As voluntary goal-directed movements induce the desynchronization of mu rhythm, we aimed at exploring whether the response-related brain activity during the touchscreen visual discrimination (VD) task is suitable to detect sensorimotor rhythms and their change under cognitive impairment. Different doses of scopolamine or MK-801 were injected subcutaneously to rats, and epidural electroencephalogram (EEG) was recorded during task performance. Arciform ~ 10 Hz oscillations appeared during visual processing, then two characteristic alpha/beta desynchronization-resynchronization patterns emerged mainly above the sensorimotor areas, serving presumably different motor functions. Beyond causing cognitive impairment, both drugs supressed the touch-related upper alpha (10–15 Hz) reactivity for desynchronization. Reaction time predominantly correlated positively with movement-related alpha and beta power both in normal and impaired conditions. These results support the existence of a mu homologue rodent rhythm whose upper alpha component appeared to be modulated by cholinergic and glutamatergic mechanisms and its power change might indicate a potential EEG correlate of processing speed. The VD task can be utilized for the investigation of sensorimotor rhythms in rats. [ABSTRACT FROM AUTHOR]

Resting brain (rs) activity has been shown to be a reliable predictor of the level of foreign language (L2) proficiency younger adults can achieve in a given time-period. Since rs properties change over the lifespan, we investigated whether L2 attainment in older adults (aged 64–74 years) is also predicted by individual differences in rs activity, and to what extent rs activity itself changes as a function of L2 proficiency. To assess how neuronal assemblies communicate at specific frequencies to facilitate L2 development, we examined localized and global measures (Minimum Spanning Trees) of connectivity. Results showed that central organization within the beta band (~ 13–29.5 Hz) predicted measures of L2 complexity, fluency and accuracy, with the latter additionally predicted by a left-lateralized centro-parietal beta network. In contrast, reduced connectivity in a right-lateralized alpha (~ 7.5–12.5 Hz) network predicted development of L2 complexity. As accuracy improved, so did central organization in beta, whereas fluency improvements were reflected in localized changes within an interhemispheric beta network. Our findings highlight the importance of global and localized network efficiency and the role of beta oscillations for L2 learning and suggest plasticity even in the ageing brain. We interpret the findings against the background of networks identified in socio-cognitive processes. [ABSTRACT FROM AUTHOR]

The stereotaxic brain atlas is a fundamental reference tool commonly used in the field of neuroscience. Here we provide a brief history of brain atlas development and clarify three key conceptual elements of stereotaxic brain atlasing: brain image, atlas, and stereotaxis. We also refine four technical indices for evaluating the construction of atlases: the quality of staining and labeling, the granularity of delineation, spatial resolution, and the precision of spatial location and orientation. Additionally, we discuss state-of-the-art technologies and their trends in the fields of image acquisition, stereotaxic coordinate construction, image processing, anatomical structure recognition, and publishing: the procedures of brain atlas illustration. We believe that the use of single-cell resolution and micron-level location precision will become a future trend in the study of the stereotaxic brain atlas, which will greatly benefit the development of neuroscience. [ABSTRACT FROM AUTHOR]

Neurofeedback through visual, auditory, or tactile sensations improves cognitive functions and alters the activities of daily living. However, some people, such as children and the elderly, have difficulty concentrating on neurofeedback for a long time. Constant stressless neurofeedback for a long time may be achieved with auditory neurofeedback using music. The primary purpose of this study was to clarify whether music-based auditory neurofeedback increases the power of the alpha wave in healthy subjects. During neurofeedback, white noise was superimposed on classical music, with the noise level inversely correlating with normalized alpha wave power. This was a single-blind, randomized control crossover trial in which 10 healthy subjects underwent, in an assigned order, normal and random feedback (NF and RF), either of which was at least 4 weeks long. Cognitive functions were evaluated before, between, and after each neurofeedback period. The secondary purpose was to assess neurofeedback-induced changes in cognitive functions. A crossover analysis showed that normalized alpha-power was significantly higher in NF than in RF; therefore, music-based auditory neurofeedback facilitated alpha wave induction. A composite category-based analysis of cognitive functions revealed greater improvements in short-term memory in subjects whose alpha-power increased in response to NF. The present study employed a long period of auditory alpha neurofeedback and achieved successful alpha wave induction and subsequent improvements in cognitive functions. Although this was a pilot study that validated a music-based alpha neurofeedback system for healthy subjects, the results obtained are encouraging for those with difficulty in concentrating on conventional alpha neurofeedback. Trial registration: 2018077NI, date of registration: 2018/11/27 [ABSTRACT FROM AUTHOR]

Here we attempted to define the relationship between: EEG activity, personality and coping during lockdown. We were in a unique situation since the COVID-19 outbreak interrupted our independent longitudinal study. We already collected a significant amount of data before lockdown. During lockdown, a subgroup of participants willingly continued their engagement in the study. These circumstances provided us with an opportunity to examine the relationship between personality/cognition and brain rhythms in individuals who continued their engagement during lockdown compared to control data collected well before pandemic. The testing consisted of a one-time assessment of personality dimensions and two sessions of EEG recording and deductive reasoning task. Participants were divided into groups based on the time they completed the second session: before or during the COVID-19 outbreak 'Pre-pandemic Controls' and 'Pandemics', respectively. The Pandemics were characterized by a higher extraversion and stronger connectivity, compared to Pre-pandemic Controls. Furthermore, the Pandemics improved their cognitive performance under long-term stress as compared to the Pre-Pandemic Controls matched for personality traits to the Pandemics. The Pandemics were also characterized by increased EEG connectivity during lockdown. We posit that stronger EEG connectivity and higher extraversion could act as a defense mechanism against stress-related deterioration of cognitive functions. [ABSTRACT FROM AUTHOR]

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Published data indicate that impairments to dopaminergic secretion in the shell of the nucleus accumbens play a role in the pathogenesis of Alzheimer's disease (ad). The likely cause is an increase in the toxic form of β-amyloid in the brain. Like other pathogenetic processes in AD, this impairment may be mediated by an increase in glycogen synthase kinase 3 (GSK3) activity. The aim of the present work was to study the effect of β-amyloid on dopamine release in the shell of the nucleus accumbens. Changes in the dopamine level in the shell of the nucleus accumbens were recorded in vivo in 38 anesthetized male Wistar rats by fast scan cyclic voltammetry before and 1.5 h after experimental treatment. The ability of dopaminergic neurons to secrete dopamine was assessed in terms of the amplitude of responses to electrical stimulation of the ventral tegmental area (VTA). Neurotoxic processes typical of AD were modeled by giving β-amyloid (fragment 25–35) solution into the ventricular system of the brain. The role of GSK34 in mediating the effects of β-amyloid were evaluated by blocking the activity of this enzyme with an inhibitor, i.e., lithium. Lithium chloride solution at the "therapeutic" dose of 10.4 mg/kg was given i.p. immediately after β-amyloid injections. Increases in stimulated dopamine release provided evidence that during the 1.5 h after administration of both β-amyloid and lithium, the ability of ventral tegmental area neurons to secret dopamine in the shell of the nucleus accumbens was increased. Furthermore, comparison with the control group showed that these substances countered weakening of the secretory function induced by the experimental conditions. Lithium given simultaneously with β-amyloid weakened its action, evidencing involvement of GSK3 in this process. [ABSTRACT FROM AUTHOR]

Subdivisions of mouse whisker somatosensory thalamus project to cortex in a region-specific and layer-specific manner. However, a clear anatomical dissection of these pathways and their functional properties during whisker sensation is lacking. Here, we use anterograde trans-synaptic viral vectors to identify three specific thalamic subpopulations based on their connectivity with brainstem. The principal trigeminal nucleus innervates ventral posterior medial thalamus, which conveys whisker-selective tactile information to layer 4 primary somatosensory cortex that is highly sensitive to self-initiated movements. The spinal trigeminal nucleus innervates a rostral part of the posterior medial (POm) thalamus, signaling whisker-selective sensory information, as well as decision-related information during a goal-directed behavior, to layer 4 secondary somatosensory cortex. A caudal part of the POm, which apparently does not receive brainstem input, innervates layer 1 and 5A, responding with little whisker selectivity, but showing decision-related modulation. Our results suggest the existence of complementary segregated information streams to somatosensory cortices. The thalamus provides sensory input to the cortex, but many aspects of thalamocortical signaling remain unknown. Here, the authors reveal parallel non-overlapping thalamic pathways with distinct representations of tactile and decision-related information during a goal-directed sensorimotor task. [ABSTRACT FROM AUTHOR]

Contemplative practices are thought to modify one's experience of self and fundamentally change self-referential processing. However, few studies have examined the brain correlates of self-referential processing in long-term meditators. Here, we used the self-referential encoding task (SRET) to examine event-related potentials (ERP) during assessment of pleasant and unpleasant self-views in long-term meditators versus age-matched meditation-naïve control participants. Compared with controls, meditators endorsed significantly more pleasant and fewer unpleasant words as self-referential. We also found a between-group difference in the early component of the late-positive-potential (LPP) of the ERP characterized by a larger response to unpleasant versus pleasant words in controls and no difference in meditators. A cross-sectional design, such as the one used in the present study, has certain caveats like self-selectivity bias. If such caveats did not affect our results, these findings suggest that a long-term contemplative lifestyle, of which meditation training is an integral part, alters self-referential processing towards a more adaptive view of self and neural equivalence towards pleasant and unpleasant self-views. These findings suggest that long-term meditation training may affect brain and behavioural mechanism that support a more flexible and healthy relationship to one's self. [ABSTRACT FROM AUTHOR]

An improved understanding of the structure-function relationship in the brain is necessary to know to what degree structural connectivity underpins abnormal functional connectivity seen in disorders. We integrated high-field resting-state fMRI-based functional connectivity with high-resolution macro-scale diffusion-based and meso-scale neuronal tracer-based structural connectivity, to obtain an accurate depiction of the structure-function relationship in the rat brain. Our main goal was to identify to what extent structural and functional connectivity strengths are correlated, macro- and meso-scopically, across the cortex. Correlation analyses revealed a positive correspondence between functional and macro-scale diffusion-based structural connectivity, but no significant correlation between functional connectivity and meso-scale neuronal tracer-based structural connectivity. Zooming in on individual connections, we found strong functional connectivity in two well-known resting-state networks: the sensorimotor and default mode network. Strong functional connectivity within these networks coincided with strong short-range intrahemispheric structural connectivity, but with weak heterotopic interhemispheric and long-range intrahemispheric structural connectivity. Our study indicates the importance of combining measures of connectivity at distinct hierarchical levels to accurately determine connectivity across networks in the healthy and diseased brain. Although characteristics of the applied techniques may affect where structural and functional networks (dis)agree, distinct structure-function relationships across the brain could also have a biological basis. [ABSTRACT FROM AUTHOR]

We created a volumetric template of the marmoset (Callithrix jacchus) brain, which enables localization of the cortical areas defined in the Paxinos et al. (The marmoset brain in stereotaxic coordinates. Elsevier Academic Press, Cambridge, 2012) marmoset brain atlas, as well as seven broader cortical regions (occipital, temporal, parietal, prefrontal, motor, limbic, insular), different brain compartments (white matter, gray matter, cerebro-spinal fluid including ventricular spaces), and various other structures (brain stem, cerebellum, olfactory bulb, hippocampus). The template was designed from T1-weighted MR images acquired using a 3 T MRI scanner. It was based on a single fully segmented marmoset brain image, which was transported onto the mean of 13 adult marmoset brain images using a diffeomorphic strategy that fully preserves the brain topology. In addition, we offer an automatic segmentation pipeline which fully exploits the proposed template. The segmentation pipeline was quantitatively assessed by comparing the results of manual and automated segmentations. An associated program, written in Python, can be used from a command-line interface, or used interactively as a module of the 3DSlicer software. This program can be applied to the analysis of multimodal images, to map specific cortical areas in lesions or to define the seeds for further tractography analyses. [ABSTRACT FROM AUTHOR]

This essay argues that there are concrete emotion regulation practices described, but not developed, in Kierkegaard’s Christian Discourses. These practices—such as attentiveness to emotion, attentional deployment, and cognitive reappraisal—help the reader to regulate her emotions, to get rid of negative, unwanted emotions such as worry, and to cultivate and nourish positive emotions such as faith, gratitude, and trust. An examination of the Discourses also expose Kierkegaard’s understanding of the emotions; his view is akin to a perceptual theory of the emotions that closely connects emotions and concerns. In particular, this analysis unearths two main regulatory strategies located in the Discourses, strategies that closely resemble present-day psychological accounts of emotion regulation. I conclude that contemporary research reinforces Kierkegaard’s philosophical analysis of emotions and emotion-regulation strategies. Drawing on this research provides the most persuasive interpretation of Kierkegaard’s understanding of the emotions and emotion-regulation strategies. Additionally, present-day research clarifies the otherwise elusive, opaque strategies he describes. Finally, my analysis demonstrates that Kierkegaard’s work can uniquely contribute to the present-day psychological research by emphasizing the need for diachronic regulation strategies, while the contemporary literature overwhelmingly focuses on synchronic strategies. [ABSTRACT FROM AUTHOR]

Diffusion MRI (dMRI)-based tractography offers unique abilities to map whole-brain structural connections in human and animal brains. However, dMRI-based tractography indirectly measures white matter tracts, with suboptimal accuracy and reliability. Recently, sophisticated methods including constrained spherical deconvolution (CSD) and global tractography have been developed to improve tract reconstructions through modeling of more complex fiber orientations. Our study aimed to determine the accuracy of connectome reconstruction for three dMRI-based tractography approaches: diffusion tensor (DT)-based, CSD-based and global tractography. Therefore, we validated whole brain structural connectome reconstructions based on ten ultrahigh-resolution dMRI rat brain scans and 106 cortical regions, from which varying tractography parameters were compared against standardized neuronal tracer data. All tested tractography methods generated considerable numbers of false positive and false negative connections. There was a parameter range trade-off between sensitivity: 0.06-0.63 interhemispherically and 0.22-0.86 intrahemispherically; and specificity: 0.99-0.60 interhemispherically and 0.99-0.23 intrahemispherically. Furthermore, performance of all tractography methods decreased with increasing spatial distance between connected regions. Similar patterns and trade-offs were found, when we applied spherical deconvolution informed filtering of tractograms, streamline thresholding and group-based average network thresholding. Despite the potential of CSD-based and global tractography to handle complex fiber orientations at voxel level, reconstruction accuracy, especially for long-distance connections, remains a challenge. Hence, connectome reconstruction benefits from varying parameter settings and combination of tractography methods to account for anatomical variation of neuronal pathways. [ABSTRACT FROM AUTHOR]

Data on the species composition and distribution of ichthyoplankton in Onega Bay of the White Sea are presented for June-July 2007, 2010-2012, and 2015-2016. In the ichthyoplankton, the specimens of the early developmental stages of 21 fish species were registered; the larvae of the White Sea herring Clupea pallasi marisalbi, capelin Mallotus villosus, and Pacific sand lance Ammodytes hexapterus were the most abundant. It is shown that the northwestern and southeastern zones, distinguished in Onega Bay by hydrophysical parameters, also differ in species composition and in ichthyoplankton abundance. [ABSTRACT FROM AUTHOR]

Rodents explore their surroundings through whisking by localizing objects and detecting textures very precisely. During such tactile exploration, whisker deflection is first mechanically transduced by receptors and then information encoded throughout the somatosensory pathway ending in the somatosensory 'barrel' cortex. In the barrel cortex, tactile information from a single whisker is segregated and processed in a cortical column corresponding to the deflected whisker. Local Field Potentials (LFPs) generated by whisker deflection in the barrel cortex present typical signatures in terms of shape and amplitude that are related to the activation of the local neuronal populations. Therefore, rigorous analysis of such responses may reveal important features about the function of underlying neuronal microcircuits. In this context, software methods for characterizing single-trial LFPs are needed that are also suitable for online extraction of LFP features and for brain-machine interfacing applications. In this work, we present an automated and efficient method to analyze evoked LFP responses in the rat barrel cortex through automatic removal of stimulation artifacts, detection of single events and characterization of their relevant parameters. Evoked single-trial LFPs recorded under two different anesthetics are examined to demonstrate the feasibility, accuracy and applicability of the method. [ABSTRACT FROM AUTHOR]

The early developmental stages of capelin Mallotus villosus and lesser sandeel Ammodytes marinus were the major representatives of the fish larvae in the ichthyoplankton of the open waters of the White Sea in June 2007 and 2010 and in July 2010 and 2011. The larvae of these two species were widely distributed in the White Sea and have been registered in the large bays and in the other parts of the sea. The larvae of capelin and lesser sandeel were the most abundant in Onega Bay and in Dvina Bay and in Gorlo Strait of the White Sea; the larvae of lesser sandeel have also been found in the coastal waters of Kandalaksha Bay. The schooling of the larvae of these two species were characterized by a relatively permanent localization that referred to the spawning grounds; the shape and the location of the schoolings usually depend on the presence and configuration of the areas of the pronounced gradients of the hydrophysical parameters in these areas. [ABSTRACT FROM AUTHOR]

On the basis of materials collected during June 18-26, 2012, in three polygons in Onega (Ukhta Inlet) and Kandalaksha (Chupa and Knyazhaya inlets) bays of the White Sea, the effect of concentration and size-species structure of the zooplankton and of the amount of potential predators on the numbers and growth rate of larvae of the White Sea herring Clupea pallasii marisalbi are considered. The total numbers of zooplankton in Ukhta, Chupa, and Knyazhaya inlets (25041, 39162-76555, and 18459-33870 ind/m, respectively) noticeably exceeds minimal values necessary for the growth and development of larvae. Correlation analysis of the size composition of larval herring and size-species composition of net mesoplankton indicates that food preferences of larvae of different size groups significantly differ. The growth rate of larvae in Kandalaksha Bay is 0.20-0.25 mm/day. A feedback between the numbers of larvae of the White Sea herring and hydromedusas was revealed: in Chupa Inlet at a greater concentration of jelly-bodied zooplankton, the numbers of larvae were considerably lower, and their reduction at 5 days turned out to be more significant than at a relatively low concentration of medusas in Knyazhaya Inlet. This indicates that food conditions are not always a single and decisive factor responsible for the formation of strong or weak-year classes of herring. [ABSTRACT FROM AUTHOR]

The Scalable Brain Atlas (SBA) is a collection of web services that provide unified access to a large collection of brain atlas templates for different species. Its main component is an atlas viewer that displays brain atlas data as a stack of slices in which stereotaxic coordinates and brain regions can be selected. These are subsequently used to launch web queries to resources that require coordinates or region names as input. It supports plugins which run inside the viewer and respond when a new slice, coordinate or region is selected. It contains 20 atlas templates in six species, and plugins to compute coordinate transformations, display anatomical connectivity and fiducial points, and retrieve properties, descriptions, definitions and 3d reconstructions of brain regions. The ambition of SBA is to provide a unified representation of all publicly available brain atlases directly in the web browser, while remaining a responsive and light weight resource that specializes in atlas comparisons, searches, coordinate transformations and interactive displays. [ABSTRACT FROM AUTHOR]

Dysregulated processing of natural rewards may be a central pathogenic process in the etiology and maintenance of prescription opioid misuse and addiction among chronic pain patients. This study examined whether a Mindfulness-Oriented Recovery Enhancement (MORE) intervention could augment natural reward processing through training in savoring as indicated by event-related brain potentials (ERPs). Participants were chronic pain patients at risk for opioid misuse who were randomized to 8 weeks of MORE (n = 11) or a support group control condition (n = 18). ERPs to images representing naturally rewarding stimuli (e.g., beautiful landscapes, intimate couples) and neutral images were measured before and after 8 weeks of treatment. Analyses focused on the late positive potential (LPP)-an ERP response in the 400-1,000 ms time window thought to index allocation of attention to emotional information. Treatment with MORE was associated with significant increases in LPP response to natural reward stimuli relative to neutral stimuli which were correlated with enhanced positive affective cue-responses and reductions in opioid craving from pre- to post-treatment. Findings suggest that cognitive training regimens centered on strengthening attention to natural rewards may remediate reward processing deficits underpinning addictive behavior. [ABSTRACT FROM AUTHOR]

The past decade has witnessed a renewed interest in cortical local field potentials (LFPs) - that is, extracellularly recorded potentials with frequencies of up to ∼500 Hz. This is due to both the advent of multielectrodes, which has enabled recording of LFPs at tens to hundreds of sites simultaneously, and the insight that LFPs offer a unique window into key integrative synaptic processes in cortical populations. However, owing to its numerous potential neural sources, the LFP is more difficult to interpret than are spikes. Careful mathematical modelling and analysis are needed to take full advantage of the opportunities that this signal offers in understanding signal processing in cortical circuits and, ultimately, the neural basis of perception and cognition. [ABSTRACT FROM AUTHOR]

Brain atlases are important tools of neuroscience. Traditionally prepared in paper book format, more and more commonly they take digital form which extends their utility. To simplify work with different atlases, to lay the ground for developing universal tools which could abstract from the origin of the atlas, efforts are being made to provide common interfaces to these atlases. 3D Brain Atlas Reconstructor service (3dBARs) described here is a repository of digital representations of different brain atlases in CAF format which we recently proposed and a repository of 3D models of brain structures. A graphical front-end is provided for creating and viewing the reconstructed models as well as the underlying 2D atlas data. An application programming interface (API) facilitates programmatic access to the service contents from other websites. From a typical user's point of view, 3dBARs offers an accessible way to mine publicly available atlasing data with a convenient browser based interface, without the need to install extra software. For a developer of services related to brain atlases, 3dBARs supplies mechanisms for enhancing functionality of other software. The policy of the service is to accept new datasets as delivered by interested parties and we work with the researchers who obtain original data to make them available to the neuroscience community at large. The functionality offered by the 3dBARs situates it at the core of present and future general atlasing services tying it strongly to the global atlasing neuroinformatics infrastructure. [ABSTRACT FROM AUTHOR]

One of the challenges of modern neuroscience is integrating voluminous data of diferent modalities derived from a variety of specimens. This task requires a common spatial framework that can be provided by brain atlases. The first atlases were limited to two-dimentional presentation of structural data. Recently, attempts at creating 3D atlases have been made to offer navigation within non-standard anatomical planes and improve capability of localization of different types of data within the brain volume. The 3D atlases available so far have been created using frameworks which make it difficult for other researchers to replicate the results. To facilitate reproducible research and data sharing in the field we propose an SVG-based Common Atlas Format (CAF) to store 2D atlas delineations or other compatible data and 3D Brain Atlas Reconstructor (3dBAR), software dedicated to automated reconstruction of three-dimensional brain structures from 2D atlas data. The basic functionality is provided by (1) a set of parsers which translate various atlases from a number of formats into the CAF, and (2) a module generating 3D models from CAF datasets. The whole reconstruction process is reproducible and can easily be configured, tracked and reviewed, which facilitates fixing errors. Manual corrections can be made when automatic reconstruction is not sufficient. The software was designed to simplify interoperability with other neuroinformatics tools by using open file formats. The content can easily be exchanged at any stage of data processing. The framework allows for the addition of new public or proprietary content. [ABSTRACT FROM AUTHOR]

The recent development of large multielectrode recording arrays has made it affordable for an increasing number of laboratories to record from multiple brain regions simultaneously. The development of analytical tools for array data, however, lags behind these technological advances in hardware. In this paper, we present a method based on forward modeling for estimating current source density from electrophysiological signals recorded on a two-dimensional grid using multi-electrode rectangular arrays. This new method, which we call two-dimensional inverse Current Source Density (iCSD 2D), is based upon and extends our previous one- and three-dimensional techniques. We test several variants of our method, both on surrogate data generated from a collection of Gaussian sources, and on model data from a population of layer 5 neocortical pyramidal neurons. We also apply the method to experimental data from the rat subiculum. The main advantages of the proposed method are the explicit specification of its assumptions, the possibility to include system-specific information as it becomes available, the ability to estimate CSD at the grid boundaries, and lower reconstruction errors when compared to the traditional approach. These features make iCSD 2D a substantial improvement over the approaches used so far and a powerful new tool for the analysis of multielectrode array data. We also provide a free GUI-based MATLAB toolbox to analyze and visualize our test data as well as user datasets. [ABSTRACT FROM AUTHOR]

We describe a computational method for assessing functional connectivity in sensory neuronal networks. The method, which we term cross-trial correlation, can be applied to signals representing local field potentials (LFPs) evoked by sensory stimulations and utilizes their trial-to-trial variability. A set of single trial samples of a given post-stimulus latency from consecutive evoked potentials (EPs) recorded at a given site is correlated with such sets for all other latencies and recording sites. The results of this computation reveal how neuronal activities at various sites and latencies correspond to activation of other sites at other latencies. The method was used to investigate the functional connectivity of thalamo-cortical network of somatosensory system in behaving rats at two levels of alertness: habituated and aroused. We analyzed potentials evoked by vibrissal deflections recorded simultaneously from the ventrobasal thalamus and barrel cortex. The cross-trial correlation analysis applied to the early post-stimulus period (<25 ms) showed that the magnitude of the population spike recorded in the thalamus at 5 ms post-stimulus correlated with the cortical activation at 6-13 ms post-stimulus. This correlation value was reduced at 6-9 ms, i.e. at early postsynaptic cortical response, with increased level of the animals' arousal. Similarly, the aroused state diminished positive thalamo-cortical correlation for subsequent early EP waves, whereas the efficacy of an indirect cortico-fugal inhibition (over 15 ms) did not change significantly. Thus we were able to characterize the state related changes of functional connections within the thalamo-cortical network of behaving animals. [ABSTRACT FROM AUTHOR]

Local field potentials have good temporal resolution but are blurred due to the slow spatial decay of the electric field. For simultaneous recordings on regular grids one can reconstruct efficiently the current sources (CSD) using the inverse Current Source Density method (iCSD). It is possible to decompose the resultant spatiotemporal information about the current dynamics into functional components using Independent Component Analysis (ICA). We show on test data modeling recordings of evoked potentials on a grid of 4×5×7 points that meaningful results are obtained with spatial ICA decomposition of reconstructed CSD. The components obtained through decomposition of CSD are better defined and allow easier physiological interpretation than the results of similar analysis of corresponding evoked potentials in the thalamus. We show that spatiotemporal ICA decompositions can perform better for certain types of sources but it does not seem to be the case for the experimental data studied. Having found the appropriate approach to decomposing neural dynamics into functional components we use the technique to study the somatosensory evoked potentials recorded on a grid spanning a large part of the forebrain. We discuss two example components associated with the first waves of activation of the somatosensory thalamus. We show that the proposed method brings up new, more detailed information on the time and spatial location of specific activity conveyed through various parts of the somatosensory thalamus in the rat. [ABSTRACT FROM AUTHOR]

Estimation of the continuous current-source density in bulk tissue from a finite set of electrode measurements is a daunting task. Here we present a methodology which allows such a reconstruction by generalizing the one-dimensional inverse CSD method. The idea is to assume a particular plausible form of CSD within a class described by a number of parameters which can be estimated from available data, for example a set of cubic splines in 3D spanned on a fixed grid of the same size as the set of measurements. To avoid specificity of particular choice of reconstruction grid we add random jitter to the points positions and show that it leads to a correct reconstruction. We propose different ways of improving the quality of reconstruction which take into account the sources located outside the recording region through appropriate boundary treatment. The efficiency of the traditional CSD and variants of inverse CSD methods is compared using several fidelity measures on different test data to investigate when one of the methods is superior to the others. The methods are illustrated with reconstructions of CSD from potentials evoked by stimulation of a bunch of whiskers recorded in a slab of the rat forebrain on a grid of 4×5×7 positions. [ABSTRACT FROM AUTHOR]

Evoked potentials (EPs) recorded within the primary sensory cortex of non-anesthetized rats vary considerably with each peripheral stimulation. We have previously shown that most of this variance reflects the shift of cortical activation between habituated and aroused states. Here we show that a method of matching the potential’s course by wavelet functions can reliably differentiate single EPs and may therefore, be used as a probe for indicating the current activation state of the cortex. [ABSTRACT FROM AUTHOR]

The location of different cloned transposable elements was determined in the polytene chromosomes of gt wand Oregon RC inbred Drosophila melanogaster stocks. Each stock was found to have about 300 hybridization sites for 12 different clones. The arrangement of the clones in the chromosomes was identical in individuals of the same stock but differed significantly between the two stocks studied. Only 10% of the localisation sites of the clones did not change their location in the chromosomes. Calculations showed that each band of a polytene chromosome may contain transposable elements. Thus these elements provide a high level of structural heterozygosis in the chromosomes of hybrid individuals. There was a slight but statistically significant tendency of transposable elements to form clusters in certain chromosomal regions. The number of chromosomal regions that they occupied was 80% of the number expected for a random distribution. A concentration of transposable elements occurred in the chromosomal regions adjacent to the chromocenter, in histone and 5S RNA loci. The banding pattern of homologous chromosomal regions as revealed by electron microscopy was similar in both D. melanogaster stocks although they differed greatly in the arrangement of transposable elements. It is likely that the structural heterozygosis provided by transposable elements in heterozygous individuals influences the frequency of genetic recombination in affected chromosomal regions, disturbs the time course of DNA synthesis, and changes the efficiency of transcription. [ABSTRACT FROM AUTHOR]

Despite a growing literature supporting the salutary effects of mindfulness meditation on emotion regulation, the underlying mechanisms linking neural and subjective changes occurring during the actual practice of meditation with emotion regulatory effects observed after meditation remains virtually unexplored. The current study sought to address this gap in knowledge by testing the hypothesis that adoption of internally-directed focused attention, indexed by increased alpha and theta spectral power, during brief open monitoring (OM) mindfulness meditation predicts reduced emotional reactivity, as measured by the late positive potential (LPP). Results revealed that the OM meditation did not produce demonstrable differences in alpha and theta power but did increase self-reported sleepiness relative to controls. Follow-up analyses showed that sleepiness uniquely moderated the effect of meditation on the LPP, such that less sleepiness during meditation, but not the control audio, corresponded to smaller LPPs to negative images. Change in theta, but not alpha power, between meditation and rest was positively correlated with the LPP even after controlling for sleepiness. Although the primary hypothesis was unsupported, the findings demonstrate that phenomenological and neural changes occurring during OM meditation may modulate its subsequent "off-the-cushion" effects on emotional reactivity. [ABSTRACT FROM AUTHOR]

Gamma is a ubiquitous brain rhythm hypothesized to support cognitive, perceptual, and mnemonic functions by coordinating neuronal interactions. While much correlational evidence supports this hypothesis, direct experimental tests have been lacking. Since gamma occurs as brief bursts of varying frequencies and durations, most existing approaches to manipulate gamma are either too slow, delivered irrespective of the rhythm's presence, not spectrally specific, or unsuitable for bidirectional modulation. Here, we overcome these limitations with an approach that accurately detects and modulates endogenous gamma oscillations, using closed-loop signal processing and optogenetic stimulation. We first show that the rat basolateral amygdala (BLA) exhibits prominent gamma oscillations during the consolidation of contextual memories. We then boost or diminish gamma during consolidation, in turn enhancing or impairing subsequent memory strength. Overall, our study establishes the role of gamma oscillations in memory consolidation and introduces a versatile method for studying fast network rhythms in vivo. Gamma oscillations have been proposed to underlie many cognitive and memory processes, but it has proven difficult to directly test this by manipulating them. Here, in rats, the authors show that manipulation of gamma oscillations in the amygdala affects memory consolidation. [ABSTRACT FROM AUTHOR]