Processing Of Sensory Information Research Articles

IQM-PC332, a Novel DREAM Ligand with Antinociceptive Effect on Peripheral Nerve Injury-Induced Pain.

Neuropathic pain is a form of chronic pain arising from damage of the neural cells that sense, transmit or process sensory information. Given its growing prevalence and common refractoriness to conventional analgesics, the development of new drugs with pain relief effects constitutes a prominent clinical need. In this respect, drugs that reduce activity of sensory neurons by modulating ion channels hold the promise to become effective analgesics. Here, we evaluated the mechanical antinociceptive effect of IQM-PC332, a novel ligand of the multifunctional protein downstream regulatory element antagonist modulator (DREAM) in rats subjected to chronic constriction injury of the sciatic nerve as a model of neuropathic pain. IQM-PC332 administered by intraplantar (0.01–10 µg) or intraperitoneal (0.02–1 µg/kg) injection reduced mechanical sensitivity by ≈100% of the maximum possible effect, with ED50 of 0.27 ± 0.05 µg and 0.09 ± 0.01 µg/kg, respectively. Perforated-patch whole-cell recordings in isolated dorsal root ganglion (DRG) neurons showed that IQM-PC332 (1 and 10 µM) reduced ionic currents through voltage-gated K+ channels responsible for A-type potassium currents, low, T-type, and high voltage-activated Ca2+ channels, and transient receptor potential vanilloid-1 (TRPV1) channels. Furthermore, IQM-PC332 (1 µM) reduced electrically evoked action potentials in DRG neurons from neuropathic animals. It is suggested that by modulating multiple DREAM–ion channel signaling complexes, IQM-PC332 may serve a lead compound of novel multimodal analgesics.

Computational mechanisms affecting the efficiency of resource use in the honey bee swarm

AbstractThe honey bee swarm carried out its best‐of‐N nest site computations by operating more than a dozen different information processing loops in parallel and by recruiting more resources to provide greater precision in loops evaluating the better quality sites. The positive feedback effects of recurrent recruitment by means of waggle dance signalling amplified the utilisation of the swarm's energy, memory and carrier resources. The relatively strong negative feedback effects of various attenuation mechanisms tended to reduce resource use and therefore counter‐balanced amplification for long enough for a meaningful nest site survey and quorum decision to be made. Some information processing mechanisms such as exploration tendency, waggle dance signalling, site non‐specific attenuation, noise reduction, independent site evaluation, energy efficient coding, mixed precision processing, self‐organising computation and quorum decision making were found to profoundly influence the efficiency of resource use. Significant insights were also gained into extended cognition, dark data processing, information quality and resource leakage. Finally, the energy cost of acquiring and processing sensory information was estimated.

Differential Serotonergic Modulation of Principal Neurons and Interneurons in the Anterior Piriform Cortex.

Originating from the brainstem raphe nuclei, serotonin is an important neuromodulator involved in a variety of physiological and pathological functions. Specific optogenetic stimulation of serotonergic neurons results in the divisive suppression of spontaneous, but not sensory evoked activity in the majority of neurons in the primary olfactory cortex and an increase in firing in a minority of neurons. To reveal the mechanisms involved in this dual serotonergic control of cortical activity we used a combination of in vitro electrophysiological recordings from identified neurons in the primary olfactory cortex, optogenetics and pharmacology and found that serotonin suppressed the activity of principal neurons, but excited local interneurons. The results have important implications in sensory information processing and other functions of the olfactory cortex and related brain areas.

Schizophrenia induces abnormal frequency-dependent patterns of dynamic brain network reconfiguration during an auditory oddball task

Objective. Schizophrenia is a psychiatric disorder that has been shown to disturb the dynamic top-down processing of sensory information. Various imaging techniques have revealed abnormalities in brain activity associated with this disorder, both locally and between cerebral regions. However, there is increasing interest in investigating dynamic network response to novel and relevant events at the network level during an attention-demanding task with high-temporal-resolution techniques. The aim of the work was: (i) to test the capacity of a novel algorithm to detect recurrent brain meta-states from auditory oddball task recordings; and (ii) to evaluate how the dynamic activation and behavior of the aforementioned meta-states were altered in schizophrenia, since it has been shown to impair top-down processing of sensory information. Approach. A novel unsupervised method for the detection of brain meta-states based on recurrence plots and community detection algorithms, previously tested on resting-state data, was used on auditory oddball task recordings. Brain meta-states and several properties related to their activation during target trials in the task were extracted from electroencephalography data from patients with schizophrenia and cognitively healthy controls. Main results. The methodology successfully detected meta-states during an auditory oddball task, and they appeared to show both frequency-dependent time-locked and non-time-locked activity with respect to the stimulus onset. Moreover, patients with schizophrenia displayed higher network diversity, and showed more sluggish meta-state transitions, reflected in increased dwell times, less complex meta-state sequences, decreased meta-state space speed, and abnormal ratio of negative meta-state correlations. Significance. Abnormal cognition in schizophrenia is also reflected in decreased brain flexibility at the dynamic network level, which may hamper top-down processing, possibly indicating impaired decision-making linked to dysfunctional predictive coding. Moreover, the results showed the ability of the methodology to find meaningful and task-relevant changes in dynamic connectivity and pathology-related group differences.

Cortical spreading depression induces propagating activation of the thalamus ventral posteromedial nucleus in awake mice

BackgroundAs the relay centre for processing sensory information, the thalamus may involve in the abnormal sensory procedure caused by cortical spreading depression (CSD). However, few studies have focused on the transient response of thalamus during CSD. Our study aimed to investigate the neuronal activity of mouse thalamus ventral posteromedial nucleus (VPM) during CSD by in vivo micro-endoscopic fluorescence imaging of the genetic calcium probe GCaMP6s expressed in excitatory glutamatergic neurons.MethodsThirty-four transgenic VGluT2-GCaMP6s mice were used in the experiments. An endoscope was inserted into the VPM for image acquisition. CSD was induced by KCl topically applied unilaterally on the cranial dura. Data were acquired in awake (ipsilateral or contralateral VPM, saline instead of KCl, MK-801 treatment) and anaesthetized (isoflurane, pentobarbital) states. Statistical analysis was performed using analysis of variance (ANOVA) by SPSS.ResultsWe found that after CSD induced in ipsilateral motor cortex, the neuronal activity increased and propagated from the posterior-lateral to the anterior-medial part of the VPM with an average speed of 3.47 mm/min. When CSD was induced in visual cortex, the response propagated in opposite direction, from the anterior-medial to the posterior-lateral part of the VPM. Aanaesthetics resulted in the suppression of VPM activation induced by CSD. No significant VPM activation was detected when CSD was induced in contralateral cortex or KCl was replaced by saline. When 5 mM MK-801 was applied to the dura, the electrode failed to record the DC shift of CSD, and there was no significant VPM activation after KCl application.ConclusionCSD induced propagating activation of the ipsilateral VPM in awake mice. The response might correlate to the cortical location where CSD was induced and might be affected by anaesthetics. No significant VPM activation was detected in saline and mk801 experiment results indicated that this VPM activation is due to CSD rather than mouse motion or direct effect of the KCl applying to the intact dura. This finding suggests the potential involvement of thalamus in the migraine auras.

Obesity and interoceptive awareness: A preliminary qualitative study of hospitalized adolescent girls with obesity

ObjectivesChildhood obesity has increased tenfold over the past 40 years. People with obesity present alterations of their bodily perceptions and a discrepancy between their actual body and their perceived body. One of the explanations advanced by neuroscience is the difficulty of integrating and processing sensory information, particularly the interoceptive interformation. There has been little research on this question in adolescent populations, although it is suggested that an atypical interoceptive mechanism is positively associated with the onset of psychopathologies and decreased socio-emotional skills in adulthood. We present here the first results of a qualitative research study that explores the experiential dimension of interception by obese adolescent girls in a hospitalization context and that assesses the main factors that influence interoceptive self-awareness: anxiety and pain. MethodExploratory qualitative research. T0 (30min): Initial assessments: State trait anxiety Inventory for Children (STAIC Scale), visual analog scale for pain and Multidimensional Assessment of Interoceptive Awareness (MAIA Self-Questionnaire). T1 and T2 (60min): perform three simple poses, each 1min (T1) alternated with an explanatory interview exploring the interoceptive experience (T2). ResultsThis study highlights that: (i) the severity of obesity is not positively associated with the level of interoceptive awareness; (ii) the correlation of influencing factors (pain and anxiety) and the level of awareness interoceptive is weak; (iii) the thematic categorization according to Mehling's eight interoceptive criteria demonstrates, for the participants: 1/the ability to identify their bodily perceptions by the majority of them; 2/the uneven capacity to maintain a level of attention on the body in its ensemble; 3/the ability not to worry about feelings of discomfort is influenced by hyper-rationalization or the negation of perceptions; 4/breathing appears to be the most mobilized lever to regulate attention; 5/the links between bodily perceptions and felt emotions are influenced by rationalization, bodily experience, or mood decline; 6/self-regulation is influenced by bodily experience, which enables awareness and postural readjustment; 7/listening to the body is influenced by the transfer of past bodily practices; 8/the notion of confidence in one's bodily perceptions is not always well understood and is not related to subjects’ ability to identify their internal manifestations, while perceived confidence is related to the level of rationalization and can be improved through postural practice. DiscussionAs reported in the literature, the interoceptive level of patients interviewed is generally low on the rating scales, but it appears that the MAIA results do not always reveal the perceived reality of body-self of the adolescent girls interviewed; guiding the participants in explaining their bodily experience reveals a much greater interoceptive dimension. We qualify this guided field of exploration as an interoceptive proximal zone or an interoceptive preconception zone. ConclusionWe suggest that a better understanding of the interoceptive mechanisms experienced by obese people helps guide patients towards a safer experiential dimension of their body. Future research should enrich this qualitative perspective of interoception and open up more embodied dimensions of care.

Difficulties of Tactile Sensory System Sensory Integration of Children with Down Syndrome

Sensory integration is the organization of the sense for their use. It is a neuro-biological activity that allows the reception and processing of sensory information, which in large quantity arrive to the brain, at all times. The brain's ability to successfully process tactile information allows the child to feel safe and develop a connection with those around they. Children with Down syndrome may have difficulties of sensory integration. Decreased awareness and attention to tactile stimulation is possible, which leads to a reduction in tactile discrimination and difficult manipulation of objects, or to an increased response to sensory stimuli in the form of tactile defense. The aim of the study is to examine the prevalence of sensory integration of the tactile sensory system of children with Down syndrome, and to determine the statistical significance of differences in relation to children without developmental disabilities. The total sample of respondents (N=30) consisted of two subsamples. The first subsample of respondents (N=15) consisted of children with Down syndrome, and the second subsample of respondents (N=15) consisted of children without developmental disabilities. The measurement instrument „Questionnaire for testing tactile sensory sensitivity“ with 11 variables and offered answers of possible sensory response was applied. The Mann-Whitney U test and the Wilcoxon W test at the level of statistical significance of p<0.05 were used to test the statistical significance of the differences between the subsamples of the respondents. The results of the study showed that 66.67% of children with Down syndrome have difficulties with sensory integration of the tactile sensory system. 26.67% of children are hypersensitive and 6.67% are hyposensitive. 33.33% of children with Down syndrome have a mixed type of tactile sensory response. Children with Down syndrome compared to children without developmental disabilities show better results of sensory integration of the tactile sensory system on two variables; „Walking barefoot“ and „Certain types of fabric, seams, labels, belts, cuffs, etc.“. There is a statistically significant difference at the level of p<0.05 between children with Down syndrome and children without developmental disabilities on 5 variables.

Difficulties of the tactile sensory system sensory integration of children with autism

Sensory integration represents the organization of the senses for their use. It is a neuro-biological activity that allows the reception and processing of sensory information, which in arrive from the senses in huge quantities into the brain, at any time. The ability of the brain to successfully process tactile information allows the child to feel safe and develop a connection with those around it. An autistic child is not able to register many stimuli from their environment, so insufficient or poor sensory processing can contribute to the image of autism. Children with autism spectrum difficulties have specific difficulties in touch perception. The aim of the study was to examine the prevalence of sensory integration difficulties of the tactile sensory system of children with autism spectrum disorders, and to establish the statistical significance of differences in relation to children without developmental difficulties. The total sample of subjects (N=30) consisted of two subsamples. The first subsample of subjects (N=15) consisted of children with difficulties from the autism spectrum, and the second subsample of subjects (N=15) consisted of children without developmental difficulties. The measurement instrument was the „Questionnaire for testing tactile sensory sensitivity“ with 11 variables and the offered answers of possible sensory response was applied. The Mann-Whitney U test and the Wilcoxon W test at the level of statistical significance of p<0.05 were used to examine the statistical significance of the differences between the subsamples of the subjects. The results of the study showed that 86.67 % of children with autism have difficulties in sensory integration of the tactile sensory system. The hypersensitive type of sensory response has 26.67 %, and the hyposensitive sensory response 20 % of children with autism. 40.00 % of children with autism have a mixed type of tactile sensory. There is a statistically significant difference between children with autism and children without developmental difficulties on 4 variables.

The Perirhinal Cortex Engages in Area and Layer-Specific Encoding of Item Dimensions.

The perirhinal cortex (PRC), subdivided into areas 35 and 36, belongs to the parahippocampal regions that provide polysensory input to the hippocampus. Efferent and afferent connections along its rostro-caudal axis, and of areas 35 and 36, are extremely diverse. Correspondingly functional tasks in which the PRC participates are manifold. The PRC engages, for example, in sensory information processing, object recognition, and attentional processes. It was previously reported that layer II of the caudal area 35 may be critically involved in the encoding of large-scale objects. In the present study we aimed to disambiguate the roles of the different PRC layers, along with areas 35 and 36, and the rostro-caudal compartments of the PRC, in processing information about objects of different dimensions. Here, we compared effects on information encoding triggered by learning about subtle and discretely visible (microscale) object information and overt, highly visible landmark (macroscale) information. To this end, nuclear expression of the immediate early gene Arc was evaluated using fluorescence in situ hybridization. Increased nuclear Arc expression occurred in layers III and V-VI of the middle and caudal parts of area 35 in response to both novel microscale and macroscale object exposure. By contrast, a significant increase in Arc expression occurred in area 36 only in response to microscale objects. These results indicate that area 36 is specifically involved in the encoding of small and less prominently visible items. In contrast, area 35 engages globally (layer III to VI) in the encoding of object information independent of item dimensions.

Chapter 4 - Adaptive cardiorespiratory changes to chronic continuous and intermittent hypoxia

This chapter reviews cardiorespiratory adaptations to chronic hypoxia (CH) experienced at high altitude and cardiorespiratory pathologies elicited by chronic intermittent hypoxia (CIH) occurring with obstructive sleep apnea (OSA). Short-term CH increases breathing (ventilatory acclimatization to hypoxia) and blood pressure (BP) through carotid body (CB) chemo reflex. Hyperplasia of glomus cells, alterations in ion channels, and recruitment of additional excitatory molecules are implicated in the heightened CB chemo reflex by CH. Transcriptional activation of hypoxia-inducible factors (HIF-1 and 2) is a major molecular mechanism underlying respiratory adaptations to short-term CH. High-altitude natives experiencing long-term CH exhibit blunted hypoxic ventilatory response (HVR) and reduced BP due to desensitization of CB response to hypoxia and impaired processing of CB sensory information at the central nervous system. Ventilatory changes evoked by long-term CH are not readily reversed after return to sea level. OSA patients and rodents subjected to CIH exhibit heightened CB chemo reflex, increased hypoxic ventilatory response, and hypertension. Increased generation of reactive oxygen species (ROS) is a major cellular mechanism underlying CIH-induced enhanced CB chemo reflex and the ensuing cardiorespiratory pathologies. ROS generation by CIH is mediated by nontranscriptional, disrupted HIF-1 and HIF-2-dependent transcriptions as well as epigenetic mechanisms.

Внутренняя картина болезни у пациентов с хронической болью в спине

<p style="text-align: justify;">The purpose of the work was to study the psychological mechanisms of the formation of an intrapsychic response to chronic back pain. The hypothesis was the assumption that the internal image of the disorder in patients with chronic back pain differs depending on the subjective perception of pain. Operationalization of the internal image of disorder was carried out in accordance with a four-level concept (sensitive, motivational, emotional, and intellectual levels). Psychodiagnostic tools were used: "McGill's Pain Questionnaire (Kastiro I.V., 2012), "Restoration of the locus of control" questionnaire (Belova N.A., 2002), expert assessment of compliance on a five-point scale, "Psychological factors of attitude to illness and treatment" questionnaire (Rasskazova E.I., 2016). In total, 84 patients aged 54.5±14.4 years were examined, including 52 (61.9%) women and 32 (38.1%) men who were at the inpatient stage of medical rehabilitation for dorsopathies with moderate chronic pain syndrome. The pain has lasted for 12.9±13.4 years. As a result of the study, it was found that the groups of patients with mixed and nociceptive pain differ from each other in the structure of the internal image of the disorder: patients with mixed pain have no relationship between the motivational and emotional levels with the sensitive – the level of primary processing of sensory information.</p>

Аутоподобный тип адаптации, феноменология процесса развития и адаптации человека, имеющего расстройства аутистического спектра

Autism spectrum disorder (ASD) is one of the most common developmental disorders. It includes impaired socialization and communication, stereotypical behaviors, cognitive abnormalities, and a wide range of sensory features. While most experts now agree that the social impairments seen in ASD are caused by cognitive deficits, including deficits in cognitive processing of sensory information, there is yet no generally accepted theory to explain the causes of ASD and the nature of the relationship between the deficits in the sensory, cognitive, and social domains. This paper addresses the advances in understanding the sensory-cognitive traits defining an autistic perception, particularly at early age, and presents a model of autistic adaptation (AA) suggesting that social deficits, rigid behavioral patterns, and self-stimulation can be conceived as a consequence of a suboptimal adaptation strategy brought forth by a need to cope with sensory hypersensitivity and to make the outside world a less chaotic and more predictable place. As a result of this adaptation, most children with ASD at an early age (up to 1.5-2 years) form a system of protection against external sensory stimuli perceived as excessively intense at a subjective level; this protection system includes behavioral responses aimed at limiting incoming sensory information and increasing predictability of sensations received by actively searching for the more uniform and predictable external stimuli, avoiding social interaction, narrowing activity range, and following rigid behavior patterns. Special attention is paid to a well-documented tendency of children with ASD to use peripheral vision instead of central vision (lateral glances) and to refrain from behaviors aimed on integration of auditory and visual information; these sensory behaviors, though helpful in preventing sensory overflow, lead to an even more fragmented perception of an outside world characteristic for an autistic personality. Sensory self-stimulation (stimming) is also perceived as a specific adaptive mechanism that provides a child with ASD with predictable and controllable sensations and is aimed at reducing anxiety associated with the intense and unpredictable flow of external sensory information. Further attempts to better understand the specific behaviors and perceptual traits associated with autistic adaptation may lead to development of more effective intervention programs for children with ASD. A broad range of sensory integration therapies are sought that aim to establish new behavioral responses and perception strategies helping to integrate the sensory information, cope with sensory overflow, and enable us to explore the world in a more positive and efficient way.

Гипотетический нейронный механизм слепоты невнимания

One of the approaches to neuroscientific investigation of consciousness is the study of inattentional blindness. Since this effect is the result of the absence of voluntary attention, it is highly interesting to study the latter. We proposed that the involvement of voluntary attention into the processing of sensory information requires the activation of prefrontal cortex and hippocampus, as well as a release of dopamine in the input structure of the basal ganglia, the striatum. This promotes disinhibition of neurons in the thalamus, subthalamic and pedunculopontine nuclei experiencing inhibitory influence of the basal ganglia. If neurons of the ventral striatum (where, the inputs converge from the hippocampus and the prefrontal and retrosplenial cortical areas) are activated strongly enough, the dopamine-dependent activity reorganization in the cortico-basal ganglia-thalamo-cortical loops facilitates the generation of neuronal representations of sensory stimuli in the corresponding neocortical areas. In addition, it creates the conditions for the circulation of excitation in the topographically organized thalamo-cortical loops, the loops connecting primary and higher cortical areas through high order thalamic nuclei, and loops connecting the neocortex and thalamus with the hippocampus, cerebellum, subthalamic and pedunculopontine nuclei. It is generally accepted that conscious perception is facilitated by re-excitation of higher cortical areas. If so, the time required for the conscious perception of a sensory stimulus should depend on the time of activity circulates in the loops mentioned earlier. It follows from the proposed mechanism that dopamine deficiency increases inhibition of the thalamus and decreases its excitation by the neocortex, cerebellum, subthalamic and pedunculopontine nuclei. This should lead to an increase in the interval between the two stimuli required to become aware of the second one. This consequence is in line with the well-known results of studies of inattentional blindness. They showed a similar increase in this interval in Parkinson’s disease and due to the damage of the cerebellum or pedunculopontine nucleus.

Astrocytes Adjust the Dynamic Range of Cortical Network Activity to Control Modality-Specific Sensory Information Processing

Astrocytes Adjust the Dynamic Range of Cortical Network Activity to Control Modality-Specific Sensory Information Processing

Fibromyalgia: transformation of views

Fibromyalgia (FM) is a mystery of modern rheumatology. Despite the high prevalence of FM according to special epidemiological studies, clinicians make this diagnosis rarely. The modern concept of fibromyalgia was created by Smythe and Moldofsky in the mid-70s. They introduced a new term «fibromyalgia», thereby emphasizing that this condition is more due to pain syndrome than inflammation of connective tissue. A disturbance of sensory information processing in the central nervous system (dysfunction of the pain system with the formation of central sensitization, CS) plays a key role in the pathogenesis of FM. Clinical manifestations of FM include chronic widespread pain associated with a wide range of psychosomatic disorders (sleep disorders, cognitive disorders [fibro fog], anxiety, depression, fatigue, morning stiffness, etc.). The diagnostic criteria for fibromyalgia have undergone significant changes. The latest FM diagnostic criteria were developed by the American College of Rheumatology (ACR) in 2016. According to the ACR (2016) FM criteria, a diagnosis of FM does not exclude the presence of other clinically important illnesses. Concomitant FM among patients with rheumatic diseases (RD) occurs 2–3 times more often than in the general population. Diagnostics and treatment of FM are extremely difficult for clinicians, it is especially difficult with comorbidity of FM with RD. Therefore, FM requires a multidisciplinary approach within a biopsychosocial model of pain syndrome: the treatment of a patient with RD and FM should combine anti-inflammatory therapy with a complex of methods (medications and nondrug therapy) used for FM therapy. The diagnostics of comorbid FM in patients with RD will allow for personalized and more effective analgesic therapy.

Neural markers of proactive and reactive cognitive control are altered during walking: A Mobile Brain-Body Imaging (MoBI) study

The processing of sensory information and the generation of motor commands needed to produce coordinated actions can interfere with ongoing cognitive tasks. Even simple motor behaviors like walking can alter cognitive task performance. This cognitive-motor interference (CMI) could arise from disruption of planning in anticipation of carrying out the task (proactive control) and/or from disruption of the execution of the task (reactive control). In young healthy adults, walking-induced interference with behavioral performance may not be readily observable because flexibility in neural circuits can compensate for the added demands of simultaneous loads. In this study, cognitive-motor loads were systematically increased during cued task-switching while underlying neurophysiologic changes in proactive and reactive mechanisms were measured. Brain activity was recorded from 22 healthy young adults using 64-channel electroencephalography (EEG) based Mobile Brain/Body Imaging (MoBI) as they alternately sat or walked during performance of cued task-switching. Walking altered neurophysiological indices of both proactive and reactive control. Walking amplified cue-evoked late fontal slow waves, and reduced the amplitude of target-evoked fronto-central N2 and parietal P3. The effects of walking on evoked neural responses systematically increased as the task became increasingly difficult. This may provide an objective brain marker of increasing cognitive load, and may prove to be useful in identifying seemingly healthy individuals who are currently able to disguise ongoing degenerative processes through active compensation. If, however, degeneration continues unabated these people may reach a compensatory limit at which point both cognitive performance and control of coordinated actions may decline rapidly.

Pop-out search instigates beta-gated feature selectivity enhancement across V4 layers

Visual search is a workhorse for investigating how attention interacts with processing of sensory information. Attentional selection has been linked to altered cortical sensory responses and feature preferences (i.e., tuning). However, attentional modulation of feature selectivity during search is largely unexplored. Here we map the spatiotemporal profile of feature selectivity during singleton search. Monkeys performed a search where a pop-out feature determined the target of attention. We recorded laminar neural responses from visual area V4. We first identified "feature columns" which showed preference for individual colors. In the unattended condition, feature columns were significantly more selective in superficial relative to middle and deep layers. Attending a stimulus increased selectivity in all layers but not equally. Feature selectivity increased most in the deep layers, leading to higher selectivity in extragranular layers as compared to the middle layer. This attention-induced enhancement was rhythmically gated in phase with the beta-band local field potential. Beta power dominated both extragranular laminar compartments, but current source density analysis pointed to an origin in superficial layers, specifically. While beta-band power was present regardless of attentional state, feature selectivity was only gated by beta in the attended condition. Neither the beta oscillation nor its gating of feature selectivity varied with microsaccade production. Importantly, beta modulation of neural activity predicted response times, suggesting a direct link between attentional gating and behavioral output. Together, these findings suggest beta-range synaptic activation in V4's superficial layers rhythmically gates attentional enhancement of feature tuning in a way that affects the speed of attentional selection.

EEG-Microstates Reflect Auditory Distraction After Attentive Audiovisual Perception Recruitment of Cognitive Control Networks.

Processing of sensory information is embedded into ongoing neural processes which contribute to brain states. Electroencephalographic microstates are semi-stable short-lived power distributions which have been associated with subsystem activity such as auditory, visual and attention networks. Here we explore changes in electrical brain states in response to an audiovisual perception and memorization task under conditions of auditory distraction. We discovered changes in brain microstates reflecting a weakening of states representing activity of the auditory system and strengthening of salience networks, supporting the idea that salience networks are active after audiovisual encoding and during memorization to protect memories and concentrate on upcoming behavioural response.

Place cells create landmarks

Hippocampal place cells are known to process path integration signals and sensory information about landmarks. In this issue of Neuron, Fischler-Ruiz et al., 2021 show how localized olfactory cues interact with path integration to drive place cells, turning the cues into landmarks.

Peering into the Brain through the Retrosplenial Cortex to Assess Cognitive Function of the Injured Brain.

The retrosplenial cortex (RSC) is a posterior cortical area that has been drawing increasing interest in recent years, with a growing number of studies studying its contribution to cognitive and sensory functions. From an anatomical perspective, it has been established that the RSC is extensively and often reciprocally connected with the hippocampus, neocortex, and many midbrain regions. Functionally, the RSC is an important hub of the default-mode network. This endowment, with vast anatomical and functional connections, positions the RSC to play an important role in episodic memory, spatial and contextual learning, sensory-cognitive activities, and multi-modal sensory information processing and integration. Additionally, RSC dysfunction has been reported in cases of cognitive decline, particularly in Alzheimer's disease and stroke. We review the literature to examine whether the RSC can act as a cortical marker of persistent cognitive dysfunction after traumatic brain injury (TBI). Because the RSC is easily accessible at the brain's surface using in vivo techniques, we argue that studying RSC network activity post-TBI can shed light into the mechanisms of less-accessible brain regions, such as the hippocampus. There is a fundamental gap in the TBI field about the microscale alterations occurring post-trauma, and by studying the RSC's neuronal activity at the cellular level we will be able to design better therapeutic tools. Understanding how neuronal activity and interactions produce normal and abnormal activity in the injured brain is crucial to understanding cognitive dysfunction. By using this approach, we expect to gain valuable insights to better understand brain disorders like TBI.