Reading frequency and Kawaii-Related Oshikatsu: Positive correlations with gray matter volume in Indoor lifestyles
Reading and kawaii-related oshikatsu (fan support activities) are among the most widely enjoyed hobbies. Previous studies have shown that gray matter volume (GMV) of the insular cortex is associated with the degree of alexithymia, which is linked to reduced mentalizing ability and motivation, and that inter- and intra-insular networks are related to reading. Similarly, studies suggest that by stimulating motivations for protection and caregiving, the insula-associated with empathy and reward processing-plays a role in responses to infants and other kawaii objects (i.e., objects perceived as cute). Building on this evidence, it is meaningful to investigate the neural basis of reading and kawaii-related oshikatsu within the insular cortex and to clarify its relationship with brain structure from a cognitive neuroscience perspective. Therefore, the present study tested the relationship using a sample of 82 healthy adults (52 men, 30 women) aged 22 to 65 years, controlling for demographic variables. A hierarchical multiple regression analysis using insular GMV as the dependent variable revealed significant positive associations with both reading frequency and kawaii-related oshikatsu. The finding suggests that these activities are not merely cognitive functions but are closely linked to social-cognitive processes essential for human survival, such as emotional processing, mentalizing, and nurturing behavior.
Altered brain activity during working memory in adult patients with anti-NMDAR encephalitis
Working memory (WM) deficits persist as core sequelae in anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis despite clinical recovery. This study investigated whether dysregulated neural dynamics in the executive control (ECN) and default mode networks (DMN) underlie WM dysfunction in adult patients with post-acute anti-NMDAR encephalitis.
From ancient fears to airborne threats: fMRI insights into neural fear responses
Threat perception is a fundamental aspect of human cognition, shaped by evolutionary pressures and modern environmental demands. While ancestral threats (e.g., snakes) have been shown to elicit stronger neural responses than modern threats (e.g., guns), less is known about how the brain processes airborne threats, such as depictions of individuals wearing face masks. This fMRI study investigates neural responses to ancestral, modern, and airborne threats to identify shared and distinct activation patterns. Sixty participants viewed visual stimuli from the three categories while undergoing fMRI scanning. Results showed heightened activation in the fear-processing network for all affective stimuli. In addition, activation of the ventral attention network was found for the ancestral threats. Modern threats elicited less intense responses, primarily engaging cortical regions associated with context-specific analysis. Notably, airborne threats elicited neural responses of similar intensity to ancestral threats but activated cortical regions overlapping with those for modern threats. This dual pattern highlights the brain's capacity to integrate evolutionary biases with socially constructed threat awareness. These findings underscore the importance of recognizing airborne threats as a unique category of threat processing, with implications for public health and mental well-being.
The neural response of the prefrontal cortex varies with the color difference in binocular rivalry: Evidence from fNIRS
Binocular color rivalry, a classical paradigm of visual conflict, provides a unique window into perceptual competition and cognitive control processes. In this study, we used functional near-infrared spectroscopy (fNIRS) to investigate how the prefrontal cortex (PFC) dynamically responds to increasing the color difference in binocular rivalry and to determine the relationship between these neural responses and behaviors. Results revealed a nonlinear pattern of PFC activation with increasing the color difference, accompanied by posterior shifts in perceptual centroids and reductions in reaction time (RT), suggesting a tight coupling between perceptual processing and behavioral responses. Notably, centroid-based analysis proved more sensitive than traditional mean-based measures, revealing that the frontopolar area (FPA) exhibited significant differences even with small increases in dichoptic color differences, highlighting its role in finely monitoring perceptual competition. In contrast, dorsolateral prefrontal cortex (DLPFC) showed significant engagement only when dichoptic color differences increased substantially, suggesting that it is primarily recruited for allocating attentional resources under stronger perceptual conflict. These findings illuminate how distinct PFC subregions contribute to the integration of perceptual and cognitive processes during visual conflict, offering new insights into the neural mechanisms underlying the coordination of sensory and cognitive information.
Disturbing the sound of silence: Bilateral temporal cortex stimulation and auditory mental imagery
Auditory imagery depends on temporal-cortical mechanisms that generate and sustain internal sound representations. If these mechanisms are causally involved, externally perturbing temporal cortex should alter the quality of imagery. We tested whether bilateral high-frequency transcranial random noise stimulation (hf-tRNS) over temporal cortex alters the vividness and control of auditory imagery. Forty-nine healthy adults completed two sessions on separate days, receiving Active hf-tRNS in one session and Sham in the other (order counterbalanced). The Bucknell Auditory Imagery Scale (BAIS; Vividness and Control subscales) was administered as two parallel half-forms to avoid item repetition; across the two sessions each participant completed the full BAIS, and the half-form paired with the Active session was counterbalanced across participants. Results showed reduced Control ratings under Active hf-tRNS compared with Sham, while Vividness showed a similar but weaker pattern. The effect was independent of which half was completed during Active hf-tRNS, the day-to-half mapping, the stimulation order, or prior musical training. These findings indicate that bilateral hf-tRNS can transiently disrupt the volitional control of internally generated auditory representations, plausibly by perturbing temporal-cortical dynamics that support auditory imagery.
Neural insights into observational drawing: A longitudinal resting state functional connectivity study using 7 t MRI
Observational drawing is a freehand accurate depiction of directly observed three-dimensional objects, which demands fine-grained visual analysis and sensorimotor translation through engagement of complex cognitive processes like perception, attention, visuomotor coordination, and aesthetic evaluation. Trait attributes of observational drawing that can be captured through resting state functional connectivity are largely unexplored, and limited to examining specific functional networks. This reductionist approach overlooks coalesce of different brain networks at rest to support multifaceted demands of sustained artistic practice. This longitudinal exploratory study assessed whole brain resting state functional connectivity (FC) to elucidate the global functional brain changes related to training of observational drawing, in undergraduate art students (n = 32) participating in 16-week observational drawing course, compared to control group of non-art students (n = 19), using high resolution functional MRI. Our findings showed that sustained engagement in observational drawing leads to significant brain plasticity. Specifically, we observed enhanced FC within and between the cerebellar, default mode, and salience networks regions implicated in complex motor coordination, cognitive processing, and attentional control. This research provides insights into neural mechanisms that support the development of artistic abilities like observational drawing and its potential role as a low-cost, accessible intervention for therapeutic applications in neurological and behavioural disorders.
Age-related spatial discrimination: Investigating hippocampal structural foundations
Spatial discrimination is a key cognitive skill for navigating everyday environments, and a decline in spatial discrimination is considered an early sign of pathological aging. The present study aimed to explore the aging mechanisms of spatial discrimination ability for overlapping and non-overlapping routes and its hippocampal structural basis. Sixty participants (30 young adults and 30 older adults) participated in this study. They performed a passive navigation task that required learning and discriminating four different partly overlapping routes, including both overlapping and non-overlapping segments. Moreover, all participants received structural MRI scans. The volumes of the hippocampus and its four subfields, CA1 (cornu ammonis 1), CA2/3 (cornu ammonis 2/3), CA4/DG (cornu ammonis 4/dentate gyrus), and subiculum, were extracted. The results showed that older adults performed worse than young adults on all behavioral measures of spatial discrimination, including reaction time and accuracy of the whole route, overlapping route, and non-overlapping route. However, both age groups showed improved performance with increased learning blocks. Hippocampal subfields volume reductions occurred in CA4/DG (p = 0.002, η = 0.166), while CA1 showed a marginal trend toward atrophy (p = 0.053, η = 0.065), CA2/3 (p = 0.363, η = 0.015) and subiculum (p = 0.142, η = 0.038) remained preserved. Smaller hippocampal volume correlated with slower overlapping route reaction time (r = -0.399) and smaller CA4/DG correlated with lower non-overlapping route accuracy (r = 0.386). Mediation analysis revealed that hippocampus volume mediated the relationship between age and the reaction time of overlapping route, and CA4/DG volume mediated the relationship between age and the accuracy of non-overlapping route. The results demonstrate a decrement in spatial discrimination in older adults, and the structural atrophy in hippocampus and subfield CA4/DG may be the underlying mechanism of this decline. These findings demonstrate subfield-specific mediation effects in a passive navigation paradigm, highlighting CA4/DG as a potential biomarker for age-related spatial discrimination deficits and advancing understanding of the hippocampal structural basis of spatial cognitive decline.
Neural correlates of form- and meaning-based predictability during speech perception
The processing of degraded speech can be facilitated by giving people access to its content beforehand, a phenomenon known as the "pop-out effect". This study investigates the neural correlates of this effect, focusing on the distinct contributions of predictability based on the form at the word level, or based on the meaning of the sentence level. Using functional magnetic resonance imaging (fMRI), we examined how these two types of predictability influence speech perception in normal-hearing listeners. Participants were exposed to noise-vocoded speech, with varying levels of intelligibility, and provided with either matching or non-matching visual text cues. Our findings reveal that form-based representations primarily engage the auditory cortex (superior temporal gyrus and sulcus), while meaning-based representations predominantly activate higher levels of language processing regions, such as the left inferior frontal gyrus. These results suggest that form- and meaning-based representations operate through additive top-down and integrative mechanisms, enhancing speech perception by leveraging top-down processes to organise auditory input. This study provides valuable insights into the neural mechanisms underlying speech perception and has implications for developing interventions to support individuals with auditory processing difficulties.
Frontal Power Spectrum Density in Emotional Video Viewing: Associations with Depression in Healthy Elderly and Mild Cognitive Impairment
In neurodegenerative conditions, such as Mild cognitive impairment (MCI), emotional processing is often impaired, but analogous impairments are linked to depressive symptoms, which are particularly relevant in the elderly and could represent an independent risk factor for development of dementia. This study examined frontal Power Spectral Density (PSD) in alpha, beta, and theta frequency bands in MCI and healthy participants (HP) at rest and during emotional video-viewing (positive vs negative, as compared to neutral). Moreover, the relationships between PSD and depressive symptoms were also assessed separately within each group. The results revealed significant group differences in PSD across resting-state and video-viewing conditions. MCI patients exhibited higher beta power compared to HP, above all in Right hemisphere. HP, but not MCI patients, showed significant hemispheric asymmetries (Left > Right). Notably, EEG power, specifically in theta band and particularly during emotional processing, positively correlated with depressive symptomatology in HP and MCI groups. These findings suggest a relationship between PSD and depressive symptoms in healthy ageing and neurodegenerative conditions. They also support the study of EEG biomarkers for early identification and monitoring of treatment of late-life depression and cognitive decline.
Reconfiguring Emotion-Regulation patterns in Multi-Frequency EEG networks during healthy aging
Previous research on aging-related emotional regulation from a whole-brain network perspective is limited, especially using EEG and graph-theoretical multi-frequency analyses. This study addresses this gap by examining 52 older adults (67.31 ± 5.00 years) and 108 younger adults (25.09 ± 3.00 years) from the Leipzig Study for MindBody-Emotion Interactions (LEMON) dataset. Functional brain networks were constructed across five frequency bands (delta, theta, alpha, beta, gamma) using amplitude envelope correlation (AEC), and global and local graph metrics were analyzed in relation to emotional regulation. Older adults showed greater use of suppression and less support coping. Network analyses revealed increased global efficiency in alpha and gamma bands in older adults, negatively correlating with evasive coping and adaptive cognitive emotional regulation. Hub nodes exhibited over-integration while peripheral connections degraded, suggesting compensatory reorganization that maintains basic function but reduces flexibility in emotional regulation, particularly in theta band and alpha band Default Mode Network and Salience/Ventral Attention networks. These findings highlight that high-frequency network compensation in aging may stabilize brain function but affect adaptive emotional regulation, and demonstrate the utility of EEG in capturing multi-frequency neural dynamics underlying emotional regulation.
Tourette's Syndrome as a vehicle in the search for the neural correlates of consciousness
The neurological underpinnings of Tourette's Syndrome offer an avenue to identify the neural correlates of consciousness. Neuroimaging of Tourette's Syndrome patients during the volitional control of premonitory urges highlight the involvement of the non-language dominant prefrontal portion of the frontal operculum of the inferior frontal gyrus and the anterior insular cortex in tic inhibition and decision-making processes. Further studies reveal these regions are crucial for intention, volitional control, self-awareness, perception of tangible reality, and attentional selectivity, suggesting their potential role in the neural correlates of consciousness.
Exploring facial expression processing with fast periodic visual stimulation and diverse stimuli
Facial expression recognition is a fundamental aspect of human social interaction, enabling effective communication and emotional understanding. Fast Periodic Visual Stimulation (FPVS) paradigms have recently emerged as a powerful approach for studying facial expression processing. However, previous studies often utilized identical base stimuli, making it difficult to disentangle neural responses to low-level perceptual differences from those reflecting conceptual discrimination of emotion. By introducing variability in our stimuli, we aimed to overcome these limitations and investigate neural responses to facial expressions of anger, fear, happiness, and sadness. Using EEG, robust oddball responses were observed across participants at both individual and group levels, demonstrating the paradigm's sensitivity even with brief recordings and limited post-processing. Significant neural responses were detected across key regions of interest, with the occipital and right occipito-temporal regions showing increased activity, consistent with previous studies investigating facial expression processing. This study highlights the effectiveness of the FPVS paradigm for examining emotional processing using naturalistic stimuli and provides a framework for future research into neural mechanisms underlying facial emotion recognition in diverse and pathological populations.
Episodic memory neural mechanisms: patterns, connectivity, and developmental dynamics
Episodic memory enables individuals to encode, store, and retrieve personally experienced events in their spatiotemporal contexts. This review synthesizes current cognitive neuroscience findings and proposes an integrative framework highlighting three key dimensions. First, distinct subregions of the medial temporal lobe (e.g., hippocampus, perirhinal cortex) and large-scale neocortical networks (e.g., ventral and dorsal frontoparietal networks, default mode network) play specialized roles in episodic memory processing. Second, episodic memory representations vary in both content and format, exhibiting stage-specific (e.g., encoding vs. retrieval) and region-specific (e.g., hippocampus vs. neocortex) neural patterns, as well as transformations during memory formation. Third, successful episodic memory relies on dynamic functional connectivity between the hippocampus and neocortex, supported by corresponding structural pathways. Furthermore, age and sex exert significant modulatory effects on hippocampus-neocortex connectivity and associated morphological structure. Future research should further clarify the specific roles of medial temporal and neocortical regions in episodic memory formation and examine developmental changes in inter-regional information flow, with particular attention to how age and sex shape hippocampal connectivity and subregional contributions.
Decoding tactile working memory content reveals performance relevance of parietal fMRI activity patterns
Working memory (WM) supports a range of higher order cognitive functions by enabling the short-term maintenance and manipulation of information through dynamic, distributed neural processes. In parallel to findings from the visual modality, tactile WM engages both sensory and higher-order cortical regions, but the temporal dynamics and functional significance of these areas remain incompletely understood. In this fMRI study, we used multivoxel pattern analysis to investigate how spatial features of tactile stimuli are represented and maintained across a short WM delay period. Our results reveal a dynamic engagement of contralateral primary somatosensory cortex (S1) and anterior superior parietal lobe (SPL) during initial encoding, with a shift toward bilateral posterior SPL involvement during later maintenance. Critically, decoding accuracy in the ipsilateral SPL correlated with individual task performance, suggesting that distinctiveness of WM-related representations in this region supports successful memory retention. These findings shed light on the hierarchical organization and temporal evolution of tactile spatial WM, indicating a transformation from concrete sensory to more abstract, distributed representations across parietal regions, modulated by behavioral demands.
Aerobic walking exercise training boosts thalamic connectivity in MS patients with cognitive processing speed impairment
The current study involved a single-blind, randomized controlled trial on the effects of aerobic treadmill walking exercise training compared with an active control condition as an approach to modify thalamocortical resting-state functional connectivity (RSFC) as a neurobiological correlate of cognitive processing speed (CPS) impairment in 28 fully-ambulatory persons with multiple sclerosis (MS) who were pre-screened for impaired CPS.
Event-Related potentials in visual attention to threatening and fearful Stimuli: A systematic review
This systematic review aimed to synthesize event-related potential (ERP) findings relating to the processing of threat-related visual stimuli across different stimulus categories. We included peer-reviewed, empirical studies published between 2000 and 2024 which reported ERP data in response to visual, threat-related stimuli in adult human participants. We excluded studies using non-visual modalities or non-ERP outcomes. The systematic search of PubMed and Web of Science was conducted on 1 August 2024. Study selection was performed independently by two reviewers. We narratively synthesized ERP results by stimulus type and component. Twenty-four studies met the inclusion criteria, comprising samples of healthy participants. Most of the studies used facial expressions as stimuli, while others employed images of animals (e.g. snakes and spiders), modern threats (e.g. guns, knives), or environmental scenes. Early ERP components (e.g. P1, N1, and EPN) were modulated by biologically salient stimuli, which suggests rapid attentional capture. Later components (e.g. LPP) reflected sustained engagement and cognitive evaluation, with modulation patterns varying according to stimulus type, cognitive load and participant characteristics. The type of stimulus may affect ERP markers of threat processing. The findings emphasize the value of ERPs as precise indicators of emotional attention and suggest their potential as biomarkers in clinical research.
Unraveling the link between brain injury and enhanced artistic skills
Traumatic brain injury (TBI), whether from a single incident or repeated trauma, is a heterogeneous neurological condition known for its cognitive, motor, and behavioral effects. However, its potential to influence or even enhance artistic creativity remains a lesser-studied phenomenon. This review explores evidence suggesting that TBI can give rise to novel or intensified artistic abilities, drawing on case reports and neuroimaging studies. We examine brain regions commonly involved in creative processes - including the prefrontal, parietal, temporal, and occipital cortices, as well as subcortical and limbic areas - and how TBI-related damage, such as diffuse axonal injury and focal contusions, may alter their function. Proposed mechanisms include cortical disinhibition and compensatory neuroplasticity, potentially unmasking latent creative capacities. Neuroimaging findings, including fMRI and diffusion tensor imaging (DTI), highlight altered connectivity in networks such as the default mode and executive control systems. Comparisons with conditions like frontotemporal dementia (FTD), which can also trigger emergent creativity, help distinguish trauma-induced reorganization from neurodegenerative changes. Finally, we consider implications for neurorehabilitation, particularly the therapeutic use of art, and reflect on the ethical dimensions of post-TBI artistic transformation. Artistic expression is proposed as a marker of adaptive brain plasticity and identity reconstruction following injury.
An error in our thinking: The sensory conflict hypothesis of combined action observation and motor imagery
The capacity to learn and adapt movement and skills through non-physical forms of practice provides benefits which extend across disciplines such as rehabilitation andsports. Two non-physical forms of practice are action observation (i.e., watching an action; AO) and motor imagery (i.e., cognitively simulatingperforming an action; MI). Researchers and practitioners now often adopt an integrated approach, where one observes an action while concurrently imagining the feeling of performing the action (termed congruent AOMI). Congruent AOMI results in greater corticomotor activity and improved behavioral outcomes compared to its independent counterparts. Despite existing theoretical frameworks seeking to explain these effects, empirical findings remain inconclusive. This article critically evaluates previous hypotheses before advancing an alternative - the Sensory Conflict Hypothesis (SCH). Situated in an internal modelling framework, the SCH proposes greater corticomotor activity and improved behavioral outcomes to be driven by the occurrence and reduction of sensory prediction errors, respectively. The SCH is further discussed in the context of differing actions during AOMI, where actions are associated in some form (coordinative AOMI) or differ in both action kinematics and goals (conflicting AOMI), with implications for cognitive engagement discussed. The SCH presents new, testable avenues of research to further understandthe relationship between AO and MI, and how to optimize their integration.
The neural basis of cognitive processing: A review and a speculative architecture
The purpose of this article is to explore what cognitive research can reveal about the way in which the neural system processes information. To that end, a comprehensive review of cognitive/behavioral and neuroscience models and findings is presented along with ideas as to how the human neural system has evolved. The representation of information in short-term memory (STM) is ascribed to stable oscillatory patterns across hierarchically structured functional networks of neocortical areas. These oscillatory patterns are primarily shaped by information in long-term memory (LTM) that is stored in the synaptic connections between neurons and, consequently, between neural areas. It is argued for the first time that the non-sensory and non-motor information processing stages revealed by behavioral research involve the change of potentially brain-wide oscillatory patterns that follow the reconfiguring of temporary neural networks. These network configurations can be governed by hub areas in the perceptual cortices (serving stimulus identification), the hippocampus (declarative memory), and the basal ganglia and prefrontal cortex (motor behavior, STM, and information processing). These ideas are integrated into a tentative neural Three-Level Systems (TLS) architecture comprising evolutionarily older perceptual and motor systems that are linked by a flexible central processing system located in the evolutionarily more recent association cortex.
Neural correlates of rumination and social anxiety: Mediating role of vmPFC connectivity in resting-state fMRI
Rumination is closely associated with social anxiety and is considered a key cognitive factor in its onset and persistence. Both processes engage brain functions related to self-referential cognition and emotional regulation; however, the neural pathways linking rumination and social anxiety remain incompletely understood. Using resting-state neuroimaging data from 470 participants, we conducted voxel-based functional connectivity analysis focusing on the ventromedial prefrontal cortex (vmPFC), a key region implicated in self-referential processing and affective regulation. Results showed that functional connectivity between the anterior vmPFC and the left inferior frontal gyrus (IFG) and the right superior frontal gyrus (SFG) was significantly associated with both rumination and social anxiety, and mediated their association. Notably, functional connectivity related to social anxiety was primarily observed in the anterior rather than the posterior vmPFC, suggesting that social anxiety may be closely linked to heightened sensitivity to social value and reward cues. This study reveals the central role of the vmPFC in integrating self-related cognition and emotion regulation, demonstrating how its functional connectivity mediates the influence of rumination on social anxiety, thereby deepening our understanding of the neural mechanisms underlying social anxiety.
Distractor-induced deafness: ERP correlates of auditory distractor processing
Distractor-induced deafness (DID) refers to the impaired detection of an auditory target when preceded by a rapid sequence of auditory distractors sharing the target's features. We examined whether the neural signatures underlying DID resemble those found in visual distractor-induced blindness (DIB). Participants completed a rapid serial auditory presentation (RSAP) task in which distractor number and cue-target onset asynchrony were systematically manipulated. Behaviorally, target detection declined with increasing distractor number, closely replicating the behavioral DIB effect. Event-related brain potentials (ERPs) evoked by the distractors, however, revealed modality-specific differences: In contrast to earlier DIB findings, the amplitude of a fronto-central negativity decreased with increasing distractor load in the auditory task. Whereas the ERP responses in the visual DIB setup supported the notion of a cumulative inhibitory mechanism triggered by distractors, the current DID findings are rather in line with temporal expectation accounts.
Resting-state functional connectivity insights: dorsolateral prefrontal cortex and superior parietal lobule in self-control and cognitive reappraisal
Self-control denotes the capacity to regulate impulses, modulate behavior and cognition in the service of long-term goals, especially when facing motivational conflicts. Cognitive reappraisal involves adaptively modifying one's appraisal of events through reinterpretation to reduce negative affect. Although both behavioral and neuroimaging studies support the association between self-control and cognitive reappraisal, the specific regulatory mechanisms of the prefrontal-parietal network in this relationship still require further investigation. To address this issue, this study systematically investigated the brain-behavior regulatory mechanisms between self-control and cognitive reappraisal by analyzing behavioral-neuroimaging data from 358 participants, combining resting-state functional connectivity (RSFC) and mediation analysis. The behavioral results confirmed a positive correlation between the variables. Moreover, neuroimaging results revealed the functional connectivity between the dorsolateral prefrontal cortex (dlPFC) and superior parietal lobule (SPL) was associated with self-control and played a mediating role in the association with cognitive reappraisal. Together, these findings suggest that dlPFC-SPL functional connectivity may serve as the neural basis for the association between self-control and cognitive reappraisal, providing novel insights into the association between self-control and cognitive reappraisal and offering a new neurobehavioral perspective on their interaction.
Motor beta oscillations contribute to the temporal binding effect
Agency, the feeling of controlling one's actions and their consequences, is closely linked to temporal binding, a phenomenon where the interval between a voluntary action and its outcome is subjectively compressed. While prior research has linked temporal binding to sensorimotor processes, the role of neural oscillations remains unclear. In this study, we combined electroencephalography with an automatic imitation task to examine how trial-by-trial variations in motor-related brain rhythms predict temporal binding. Twenty-eight participants performed lifting finger movements in response to visual imperative stimuli. Following each response, they estimated the interval between their action and a subsequent tone. Time-frequency analysis and linear mixed-effects modeling revealed that reduced beta desynchronization predicted stronger temporal binding, independent of action congruency. These results suggest that motor beta oscillations reflects the temporal experience of action-effect coupling, likely reflecting predictive motor processes involved in the construction of voluntary actions.
Neurophysiological correlates of short-term recognition of sounds: Insights from magnetoencephalography
This study employed a same versus different auditory paradigm to investigate short-term auditory recognition within a predictive coding (PC) framework. Using magnetoencephalography (MEG), we captured the neurophysiological correlates associated with a single-sound, short-term memory task. Twenty-six healthy participants were tasked with recognizing presented sounds as same or different compared to strings of standards. Awhite noise interlude separated targets from standards. MEG sensor-level results revealed that recognition of same sounds elicited two significantly stronger negative components of the event-related field compared to different sounds. The first, N1m, peaking 100 ms post-sound onset, while the second corresponded to a slower negative component arising between 300 and 600 ms. This effect was observed in several significant clusters of MEG sensors, especially temporal and parietal regions. Conversely, different sounds produced scattered and smaller clusters of stronger activity than same sounds, peaking later than 600 ms after sound onset. Source reconstruction using beamforming algorithms revealed involvement of auditory cortices, hippocampus, and cingulate gyrus in both conditions. Overall, results are coherent with PC principles and previous results on the brain mechanisms underlying auditory recognition, highlighting the relevance of early and later negative brain responses for successful prediction of previously listened sounds in the context of conscious short-term memory.
Effects of regional white matter hyperintensities and β-amyloid on domain-specific cognition and progression to dementia
White matter hyperintensities (WMHs) and cerebral β-amyloid (Aβ) have been characterized as clinically significant biomarkers associated with greater cognitive decline and incidence of Alzheimer's Disease (AD) dementia. However, it remains unclear how their regional manifestations co-contribute to domain-specific cognition and dementia onset. We investigated 200 cognitively normal (CN) and 523 individuals with mild cognitive impairment (MCI). We first quantified regional WMHs and Aβ accumulation in the four cerebral lobes. Next, we evaluated the effects of both WMHs and Aβ in each lobe on memory, executive function (EF), language, and visuospatial function. We used Cox proportional hazard models to determine the contributions of both regional WMHs and Aβ to dementia progression. In CN individuals, greater WMHs in parietal and temporal regions were associated with poorer EF beyond Aβ. In MCI individuals, greater Aβ burden in all lobes were associated with poorer memory, EF, and language abilities beyond WMHs. Lastly, both greater occipital WMHs and Aβ predicted progression to dementia. Temporo-parietal WMHs may drive early decline in EF beyond regional Aβ, while occipital WMHs play a critical role in disease progression to AD dementia beyond regional Aβ, highlighting the complex interplay of regional WMHs and Aβ on domain-specific cognitive and clinical function.
Microstate analysis in infancy: Examining infant brain at rest and during experimental tasks
Microstates are brief, stable states of spatial topography that are measured with electroencephalography (EEG) and thought to capture whole-brain activation patterns. EEG microstates have been associated with functional networks measured with functional magnetic resonance imaging (fMRI) in adult populations. Microstate analysis offers a unique opportunity to measure brain activity, capturing whole-brain dynamics with superior temporal sensitivity as infants engage in cognitive and emotionally salient tasks. Additionally, comparison of microstates between infants and the adult literature provide insight into functional network emergence and development. The current study examined microstates in 61 infants (ages 6-12 months) utilized a wakeful resting task in addition to laboratory tasks designed to elicit cognitive and emotional responses. The EEG microstate topographies and parameters were compared within these tasks and across activities. It was hypothesized that microstates would be extracted from infant EEG data, with resting (or baseline) topographies providing replication of previous work (Brown & Gartstein, 2023). It was hypothesized that the experimental tasks would produce four microstates similar in topography to the resting task, eliciting a calm/alert state, and that parameters would differ within and across tasks depending on the underlying functional networks needed to process information specific to each activity. Similar topographies were found across tasks and were consistent with the adult literature. Topographies and parameters differed in comparisons within and across tasks consistent with the associated functional networks. These findings point to the usefulness of microstate analysis in measuring emotional processing and cognition and how these emerge as a function of brain development.
Can you spot the funny face? An EEG study on slapstick humour processing in children
This study investigated the neural correlates of slapstick humour recognition in 4- to 5-year-old children using electroencephalography (EEG). We asked whether the development of facial expression recognition affects the capacity to identify humour in situations involving misfortune. The children completed two tasks: an Emotion Recognition Task (EmoRec), in which the children had to identify congruent and incongruent emotional expressions, and a Humour Recognition Task (HumRec), in which they were asked to distinguish humorous from non-humorous misfortunate situations. We identified specific neural correlates associated with slapstick humour processing (N170, LP) and neural correlates related to face processing (N170, P300). This suggests that children between the ages of 4 and 5 recognised emotions in faces and identified humorous information in misfortunate situations. In addition, the neural activity was correlated with humour and facial emotion recognition. This supports the hypothesis that emotional recognition contributes to understanding slapstick humour in early childhood.
The same label, different processes: What lies behind the term "mental simulation" in the embodied cognition literature?
Over recent decades, cognitive science has increasingly focused on the theory of "Embodied Cognition", an "umbrella" term that encompasses several often non-converging approaches. A main construct underlying these approaches is the notion of "Mental Simulation". This paper argues that mental simulation is far from being a unitary construct and proposes a taxonomy in which different types of mental simulations are placed on a continuum, making it possible to disentangle the complex nature of mental simulation. To support this taxonomy empirically, a series of studies are reviewed showing that mental simulation is a fundamental cognitive process, underlying several abilities (e.g., action observation, language comprehension, mental imagery). Although the same label is used in different domains, the literature review supports the necessity to distinguish mental simulations on at least two dimensions, namely the process and the result of this process. The process can be automatic or voluntary, fast or slow; the outcome can range from a mental representation to motor resonance. Our analysis underscores the importance of a nuanced understanding of the cognitive, phenomenological and neural aspects of mental simulation. This helps clarify the state of knowledge in this domain while the taxonomy provides future research with a solid conceptual ground.
Flight training-induced stage-specific reorganization of the ventral visual network in pilots: evidence from longitudinal and cross-sectional studies
Aviation safety critically depends on pilots' visual processing abilities. Understanding the plasticity of its neural mechanisms can inform flight training optimization. This study used longitudinal and cross-sectional designs to investigate how long-term flight training affects functional reorganization within the ventral and dorsal visual networks. Multimodal MRI data were collected from 136 participants across two experiments: Experiment 1 (25 flight cadets, 24 controls) and Experiment 2 (48 pilots, 39 controls). Longitudinal analysis showed that cadets exhibited a significant decrease in ventral network clustering coefficient and local efficiency after three years of training (population × time interaction). Cross-sectional results revealed that professional pilots had reduced small-worldness and global efficiency in the ventral network, both negatively correlated with flight hours, while characteristic path length was positively correlated. No significant differences were observed in the dorsal visual network. These findings suggest that flight training induces stage-specific topological remodeling of the ventral visual network, possibly through local pruning and enhanced global integration. Moreover, the ventral network demonstrates greater sensitivity to flight-related experience than the dorsal pathway. This study advances understanding of neural adaptation in aviation and offers insights into stage-specific training strategies for optimizing pilot performance.
Did increasing brain size place early humans at risk of extinction?
Increasing brain size is a hallmark of human evolution. While a larger brain offers evolutionary advantages driven by social and cognitive adaptations, it also imposes considerable energetic, metabolic, and thermoregulatory costs. As a result, brain size may have biological limits that impose survival pressures during periods of extreme environmental change. Here, temporal trends in absolute brain size across the genus Homo are analyzed, with a focus on a marked slowdown in growth beginning around 300,000 years ago. The results suggest that strong directional selection for brain expansion in early Homo was followed by a shift toward stabilizing selection in later populations. Comparisons across glacial and interglacial periods indicate that the physiological costs of large brains may have become especially disadvantageous during warming interglacial periods in the last 100,000 years, potentially increasing extinction risk. This evolutionary shift coincides with the emergence of cognitive and cultural innovations-such as symbolic tools and language-that may have enabled cognitive offloading, reducing selective pressure for continued encephalization. Together, these findings support the hypothesis that stabilizing selection, mediated in part by behavioral and technological adaptations, buffered later Homo populations against the ecological and physiological costs associated with large brains.
