Decoding six basic emotions from brain functional connectivity patterns

Dual temporal pathway model of emotion processing based on dynamic network reconfiguration analysis of EEG signals

Emotion is crucial for the quality of daily life. Recent findings suggest that the cooperation and integration of multiple brain regions are essential for effective emotion processing. Additionally, network reconfiguration has been observed during various cognitive tasks. However, it remains unclear how the brain responds to different emotional categories under natural stimuli from the perspective of network reconfiguration, or whether this reconfiguration can predict subjective rating scores. To address this question, 28 video clips were used to evoke eight distinct emotion categories, and the participants' electroencephalogram (EEG) signals were recorded. Dynamic network reconfiguration analysis was performed on brain networks extracted from band-limited EEG signals using the phase locking value (PLV) across multiple non-overlapping time windows. Robust dynamic community detection was applied to these networks, followed by quantification of integration and segregation at both node- and community-level changes. Multidimensional rating scores were collected for each clip. The analysis revealed that the metrics of dynamic network reconfiguration could predict subjective ratings. Specifically, longer EEG segments improved predictions for positive emotions, whereas shorter segments were more effective for negative emotions. Our study provides empirical evidence integrating the dual-process model and the theory of constructed emotion. Based on observed spatiotemporal patterns of global integration and segregation across the brain, we propose the dual temporal pathway model for emotional processing across various emotion categories, highlighting fast and slow neural processes associated with negative and positive emotions, respectively. These findings offer valuable support for developing temporally targeted diagnostic and therapeutic strategies for emotion-related brain disorders.

Functional Connectivity Encodes Sound Locations by Lateralization Angles

The ability to localize sound sources rapidly allows human beings to efficiently understand the surrounding environment. Previous studies have suggested that there is an auditory "where" pathway in the cortex for processing sound locations. The neural activation in regions along this pathway encodes sound locations by opponent hemifield coding, in which each unilateral region is activated by sounds coming from the contralateral hemifield. However, it is still unclear how these regions interact with each other to form a unified representation of the auditory space. In the present study, we investigated whether functional connectivity in the auditory "where" pathway encoded sound locations during passive listening. Participants underwent functional magnetic resonance imaging while passively listening to sounds from five distinct horizontal locations (-90°, -45°, 0°, 45°, 90°). We were able to decode sound locations from the functional connectivity patterns of the "where" pathway. Furthermore, we found that such neural representation of sound locations was primarily based on the coding of sound lateralization angles to the frontal midline. In addition, whole-brain analysis indicated that functional connectivity between occipital regions and the primary auditory cortex also encoded sound locations by lateralization angles. Overall, our results reveal a lateralization-angle-based representation of sound locations encoded by functional connectivity patterns, which could add on the activation-based opponent hemifield coding to provide a more precise representation of the auditory space.

EEG-based functional and effective connectivity patterns during emotional episodes using graph theoretical analysis

Understanding the neural mechanisms underlying emotional processing is critical for advancing neuroscience and mental health interventions. This study examined these mechanisms by analyzing EEG connectivity patterns across different brain regions while participants evoked various emotions. After applying independent component analysis (ICA) to eliminate non-cortical activity, we assessed frequency-specific connectivity patterns using coherence, Granger causality, and graph theoretical measures to evaluate both functional and effective connectivity. Graph theoretical analysis revealed significant differences in connectivity between emotions across multiple frequency bands, particularly in the delta and beta bands. These results indicated modulations in key brain regions, such as the precentral, superior frontal, and temporal areas, suggesting that these regions play a crucial role in emotional processing. Coherence analysis demonstrated predominant alpha band activity across all emotions, with specific emotional states, such as fear, grief, and jealousy, exhibiting enhanced beta band activity. In terms of coherence strength, we observed that the gamma band was largely inactive, except for the emotion of sadness, which displayed significant activity in the right lobe, particularly in regions such as the supplementary motor area and the lingual gyrus. Additionally, Granger causality analysis highlighted that the beta and gamma bands were dominant across all emotional states, with minimal modulation observed in the theta band. Clustering coefficients from the graph analysis further revealed distinct patterns of connectivity in the delta and beta bands, with significant variations across different emotions, particularly in the temporal and frontal regions. These findings enhance our understanding of emotional processing and have practical applications in mental health, biomarker identification, and human-computer interaction.

Age-induced changes in affective prosody comprehension and its relationship with general cognitive ability and social support utilization among older adults

Aging can impact emotional recognition, affecting older adults' mental health and social function. This study examined how aging affects affective prosody comprehension (APC: understanding emotions through speech) across seven emotions (happiness, surprise, sadness, anger, fear, disgust, and neutrality) and its relationship with cognitive function (via the Montreal Cognitive Assessment) and social support (via the Social Support Rating Scale) in 199 cognitively normal older adults. We found that older adults had lower APC accuracy and more errors, often mistaking negative emotions for neutral or positive ones. APC accuracy was significantly associated with social support, and a partial least squares (PLS) cognitive component fully mediated the relationship between the APC component and social support utilization, explaining 61.7% of the total effect. These results suggest that declines in APC during aging are linked to social support utilization through cognitive function, offering insights for interventions to improve social and cognitive health in older adults.

Emotion brain network topology in healthy subjects following passive listening to different auditory stimuli

A large body of research establishes the efficacy of musical intervention in many aspects of physical, cognitive, communication, social, and emotional rehabilitation. However, the underlying neural mechanisms for musical therapy remain elusive. This study aimed to investigate the potential neural correlates of musical therapy, focusing on the changes in the topology of emotion brain network. To this end, a Bayesian statistical approach and a cross-over experimental design were employed together with two resting-state magnetoencephalography (MEG) as controls. MEG recordings of 30 healthy subjects were acquired while listening to five auditory stimuli in random order. Two resting-state MEG recordings of each subject were obtained, one prior to the first stimulus (pre) and one after the final stimulus (post). Time series at the level of brain regions were estimated using depth-weighted minimum norm estimation (wMNE) source reconstruction method and the functional connectivity between these regions were computed. The resultant connectivity matrices were used to derive two topological network measures: transitivity and global efficiency which are important in gauging the functional segregation and integration of brain network respectively. The differences in these measures between pre- and post-stimuli resting MEG were set as the equivalence regions. We found that the network measures under all auditory stimuli were equivalent to the resting state network measures in all frequency bands, indicating that the topology of the functional brain network associated with emotional regulation in healthy subjects remains unchanged following these auditory stimuli. This suggests that changes in the emotion network topology may not be the underlying neural mechanism of musical therapy. Nonetheless, further studies are required to explore the neural mechanisms of musical interventions especially in the populations with neuropsychiatric disorders.

Effect of emotions on learning, memory, and disorders associated with the changes in expression levels: A narrative review

Emotions, in general, have no scientific definition. Emotions can be denoted as the mental state because of the neurophysiological changes. Emotions are related to mood, personality, temperament, and consciousness. People exhibit different emotions in different situations causing changes in cognitive functions. One of the major cognitive functions is the ability to learn, to store the acquired information in the parts of the brain such as the hippocampus, amygdala, cortex, and cerebellum. Learning and memory are affected by different types of emotions. Emotional responses such as fear, depression, and stress have impaired effects on cognitive functions such as learning and memory, whereas optimistic and happy emotions have positive effects on long-term memory. Certain disorders have greater effects on the regions of the brain which are also associated with synaptic plasticity and Learning and Memory(LM). Neuroimaging techniques are involved in studying the changing regions of the brain due to varied emotions and treatment strategies based on the changes observed. There are many drugs, and in advancements, nanotechnology is also utilized in the treatment of such psychiatric disorders. To improve mental health and physical health, emotional balance is most important, and effective care should be provided for people with less emotional quotient and different types of disorders to inhibit cognitive dysfunctions. In this review, emotions and their varied effects on a cognitive function named learning and memory, disorders associated with the defects of learning due to emotional instability, the areas of the brain that are in control of emotions, diagnosis, and treatment strategies for psychiatric disorders dependent on emotions are discussed.

Integrated neural tracing and in-situ barcoded sequencing reveals the logic of SCN efferent circuits in regulating circadian behaviors

The circadian clock coordinates rhythms in numerous physiological processes to maintain organismal homeostasis. Since the suprachiasmatic nucleus (SCN) is widely accepted as the circadian pacemaker, it is critical to understand the neural mechanisms by which rhythmic information is transferred from the SCN to peripheral clocks. Here, we present the first comprehensive map of SCN efferent connections and suggest a molecular logic underlying these projections. The SCN projects broadly to most major regions of the brain, rather than solely to the hypothalamus and thalamus. The efferent projections from different subtypes of SCN neurons vary in distance and intensity, and blocking synaptic transmission of these circuits affects circadian rhythms in locomotion and feeding to different extents. We also developed a barcoding system to integrate retrograde tracing with in-situ sequencing, allowing us to link circuit anatomy and spatial patterns of gene expression. Analyses using this system revealed that brain regions functioning downstream of the SCN receive input from multiple neuropeptidergic cell types within the SCN, and that individual SCN neurons generally project to a single downstream brain region. This map of SCN efferent connections provides a critical foundation for future investigations into the neural circuits underlying SCN-mediated rhythms in physiology. Further, our new barcoded tracing method provides a tool for revealing the molecular logic of neuronal circuits within heterogeneous brain regions.

The Relationship between Childhood Abuse and Suicidal Ideation among Chinese College Students: The Mediating Role of Core Self-Evaluation and Negative Emotions

Childhood abuse is a significant risk factor for suicidal ideation. However, the underlying mediation mechanism necessitates further exploration. This study investigated the mediating role of core self-evaluation and negative emotions in the relationship between childhood abuse and suicide ideation in young adults. A sample of 3103 college students from 11 universities across 8 provinces in China was analyzed. Childhood abuse, core self-evaluation, negative emotions, and suicidal ideation were assessed using the Childhood Trauma Questionnaire (CTQ-CF), Core Self-Evaluation Scale, Affect Scale, and Beck Suicidal Ideation Scale (BSI-CV), respectively. Data analysis was conducted using SPSS 19.0 and SPSS Macro Process. We found that high scores for childhood abuse were associated with elevated levels of suicidal ideation, whereas low scores for core self-evaluation were closely linked to heightened levels of negative emotions and suicidal ideation. Furthermore, core self-evaluation and negative emotions mediated the relationship between childhood abuse and suicidal ideation through three significant paths. The results demonstrate that childhood abuse can directly impact suicidal ideation in young adulthood and indirectly influence suicidal ideation by affecting core self-evaluation and negative emotions. They suggest that addressing core self-evaluation and negative emotions in individuals who have experienced childhood abuse may help prevent or treat suicidal ideation.

Functional connectivity patterns in parosmia

OBJECTIVE

Parosmia is a qualitative olfactory dysfunction presenting as "distorted odor perception" in presence of an odor source. Aim of this study was to use resting state functional connectivity to gain more information on the alteration of olfactory processing at the level of the central nervous system level.

METHODS

A cross sectional study was performed in 145 patients with parosmia (age range 20-76 years; 90 women). Presence and degree of parosmia was diagnosed on the basis of standardized questionnaires. Participants also received olfactory testing using the "Sniffin' Sticks". Then they underwent resting state scans using a 3 T magnetic resonance imaging scanner while fixating on a cross.

RESULTS

Whole brain analyses revealed reduced functional connectivity in salience as well as executive control networks. Region of interest-based analyses also supported reduced functional connectivity measures between primary and secondary olfactory eloquent areas (temporal pole, supramarginal gyrus and right orbitofrontal cortex; dorso-lateral pre-frontal cortex and the right piriform cortex).

CONCLUSIONS

Participants with parosmia exhibited a reduced information flow between memory, decision making centers, and primary and secondary olfactory areas.