Search Results (423)

Dogs are deeply social, built to stay in touch with others of their kind. In cities, though, most now live as single dogs. Housing rules, work schedules, and constant supervision have constrained their social environment. They still meet other dogs, but the meetings are short, managed, and rarely turn into real bonds. This review tries to pull together what is known about how such limited contact affects canine welfare and emotional balance. The sources come mostly from ethology, psychology, and urban studies, published between 2010 and 2025, and include comparisons between urban pets and free-ranging dogs that still organise their own social lives. Across studies, the pattern is similar: when dogs lose steady companions, they also lose the kind of social buffering that once helped them recover from stress. Over time, this does not always look like distress—more often it shows up as quiet tension, watchfulness, or an overdependence on human cues. The evidence points to social deprivation as a slow, structural welfare issue rather than an occasional problem. Meaningful improvement may therefore require moving beyond control and training alone, toward conditions that allow dogs to form small, stable circles of familiar peers that support lower arousal and more reliable recovery. Full article

Background/Objectives: People often engage in small, repetitive movements—or “fidgeting”—while listening. This behavior has traditionally been regarded as a sign of inattention. However, recent perspectives suggest that these movements may support engagement and arousal regulation. Yet, little is known about how different types of fidgeting affect the allocation of cognitive resources during auditory processing. This study examined whether hand and leg fidgeting influence pupil-linked arousal and auditory task performance. Methods: Young, healthy adults aged 18–26 years completed four auditory processing tasks while performing either hand fidgeting (manipulating a small fidget toy) or leg fidgeting (very light ergometer pedaling). A control group did not fidget. Pupil-linked arousal was assessed using changes in pupil diameter, and listening performance was evaluated across tasks of varying difficulty. Results: Both forms of fidgeting caused pupil dilation compared to the control group, particularly in the case of Hand Fidgeting during the listening task with speech in noise and the fast speech task. Despite these physiological changes, there were no measurable differences in auditory task performance across conditions. Conclusions: Fidgeting modulates pupil-linked arousal without impairing auditory processing in young, healthy adults. Hand fidgeting may help sustain engagement during demanding listening tasks. However, because the fidgeting was intentional and task performance approached ceiling or floor levels, these findings should be interpreted as preliminary. Future studies should examine whether fidgeting supports arousal maintenance or listening performance in individuals with attentional vulnerabilities or auditory processing difficulties. Full article

Excessive use of short-form video platforms such as TikTok has raised growing concerns about digital addiction and its impact on young users’ emotional well-being. This study examines the relationship between continuous TikTok exposure and emotional engagement in young adults aged 20–23 through a multimodal experimental design. The purpose of this research is to determine whether emotional engagement increases, remains stable, or declines during prolonged exposure and to assess the degree of correspondence between facially inferred engagement and physiological arousal. To achieve this, multimodal biometric data were collected using the iMotions platform, integrating galvanic skin response (GSR) sensors and facial expression analysis via Affectiva’s AFFDEX SDK 5.1. Engagement levels were binarized using a logistic transformation, and a binomial test was conducted. GSR analysis, merged with a 50 ms tolerance, revealed no significant differences in skin conductance between engaged and non-engaged states. Findings indicate that although TikTok elicits strong initial emotional engagement, engagement levels significantly decline over time, suggesting habituation and emotional fatigue. The results refine our understanding of how algorithm-driven, short-form content affects users’ affective responses and highlight the limitations of facial metrics as sole indicators of physiological arousal. Implications for theory include advancing multimodal models of emotional engagement that account for divergences between expressivity and autonomic activation. Implications for practice emphasize the need for ethical platform design and improved digital well-being interventions. The originality and value of this study lie in its controlled experimental approach that synchronizes facial and physiological signals, offering objective evidence of the temporal decay of emotional engagement during continuous TikTok use and underscoring the complexity of measuring affect in highly stimulating digital environments. Full article

Background/Objectives: Falls are a major global issue for older adults, and emotional stress may increase the risk due to its effects on postural control and balance. However, the immediate effects of a stressful stimulus on objective measures of balance and fall risk are unknown. The study aims to explore differences in older adults’ performance on the Timed Up and Go (TUG) test before and after such exposure. Methods: In this cross-sectional study, 31 older adults (71.6 ± 4.98 years) were exposed to an emotionally stressful stimulus using high-arousal images from the International Affective Picture System. Participants performed the TUG before (t1) and after (t2) exposure as the primary outcome measure. To assess the physiological and psychological impact of the stressful stimulus, heart rate variability (HRV) was recorded before and during image viewing. A visual analogue scale (VAS) of unease was completed both before and after the stimulus. Results: During the stressful stimulus, the HRV high-frequency (HF) band decreased significantly (p = 0.001), while the low-frequency (LF) band (p = 0.002) and the LF/HF ratio (p = 0.004) showed a significant increase. Similarly, after stressful stimulus, VAS scores demonstrated a statistically significant increase (p < 0.001). The time to complete the TUG showed a statistically significant increase at t2 (p < 0.001). Conclusions: The stressful stimulus triggered both physiological and subjective stress responses. Subsequently, TUG test performance declined (increased duration), suggesting that emotionally stressful stimuli could deteriorate functional balance performance in older adults, potentially increasing fall risk. Full article

Rosemary (Salvia rosmarinus) has been linked to improvements in psychological wellbeing through cholinergic mechanisms. However, this study investigated whether individual differences in eye blink rate (EBR) and blink variability (EBV), which are proxies of dopaminergic activity and attentional control, influence the cognitive and mood-enhancing properties of a rosemary-containing drink. Forty-eight healthy adults completed a three-stimulus odd-ball cognitive task under rosemary or control conditions, while vertical electrooculograms were recorded. Event-related brain potentials (ERPs) were also measured using the P3a component at the Cz scalp electrode as an additional index of dopaminergic activity. Subjective mood and arousal (alert, contented, calm) were collected pre- and post-task using Bond–Lader visual analogue scales. Reaction times during the task were modelled with ex-Gaussian parameters (μ, σ, τ). Rosemary ingestion led to increased alertness and contentedness following the task. Cognitive effects were moderated by blink metrics, with significant interactions between rosemary and blink metrics for mean reaction time μ and response variability σ. Rosemary also increased P3a amplitudes, indicative of dopaminergic contribution. The effects of rosemary on cognition and mood were moderated by individual blink profiles, indicating that baseline neurocognitive state plays a role. Although cholinergic accounts are well established, this study highlights the use of proxies of dopamine to investigate broader neurotransmitter involvement in rosemary’s enhancing properties. Full article

Ergogenic aids have long attracted scientific interest for their potential to enhance neuromuscular performance, with caffeine being among the most extensively studied. While traditionally attributed to peripheral actions on skeletal muscle, accumulating evidence indicates that, at physiological doses, caffeine’s ergogenic effects are predominantly mediated by antagonism of central adenosine receptors. This antagonism leads to increased arousal, reduced inhibitory neuromodulation, enhanced corticospinal excitability, and altered motor unit recruitment and firing behavior. Importantly, the concentrations required to elicit direct effects on excitation–contraction coupling via ryanodine receptors exceed those compatible with human safety, rendering such mechanisms unlikely in vivo. This narrative review synthesizes contemporary neurophysiological evidence to propose that caffeine acts primarily by “tuning” motor system gain through central neurotransmitter modulation, rather than by directly augmenting muscle contractile properties. Additionally, we highlight unresolved questions regarding persistent inward currents, sex-dependent neuromodulatory influences—including the potential role of estrogen in regulating adenosine receptor expression—and the implications of repeated caffeine use during training for neural adaptation and motor control. Finally, we outline key methodological and conceptual directions for future research aimed at refining our understanding of caffeine’s neuromuscular effects in both acute and chronic contexts. Full article

Background: Emerging evidence suggests that COVID-19 may influence obstructive sleep apnea (OSA) pathophysiology by affecting upper airway collapsibility, ventilatory control, and arousal responses, raising the possibility of a bidirectional relationship. This study examined whether individuals with a history of COVID-19 show altered OSA-related physiological traits compared with those without prior infection. Methods: In a case–control study, 60 participants with a history of COVID-19 were compared to 60 matched controls who underwent overnight in-hospital polysomnography before the pandemic. The matching criteria included age (±5 years), gender, body mass index (BMI) (±5 kg/m²), and OSA presence. Key pathophysiological traits (collapsibility, loop gain, arousal threshold, muscle compensation) estimated from polysomnographic signals were compared, with adjustment for age, sex, BMI, and apnea–hypopnea index. Results: The participants (78% male, mean age 55 ± 12 years, BMI 29.4 ± 5.0 kg/m²) exhibited no meaningful differences in their average levels of collapsibility (Adj dif [95% CI]; V_passive: −1 [−4, 2] %_eupnea, p = 0.7), loop gain (LG₁: 0.01 [−0.04, 0.06], p = 0.7), or arousal threshold levels (−1 [−7, 4] %_eupnea) and showed similar levels of muscle compensation (V_comp: 5 [−1, 11], p = 0.12). However, a greater ventilatory response to arousal (7 [1, 12] %_eupnea) was associated with COVID-19 history. Conclusions: COVID-19 history is not associated with differences in key OSA pathophysiological traits, suggesting it is unlikely to explain observed differences in OSA presentation. The increased ventilatory response to arousal may have implications for treatment responses and outcomes. Full article

This study investigates the influence of three biophilic interior design variables: natural light, interior vegetation (vertical green wall), and biomorphic form (biomorphic wall panel) on affective and physiological responses in a design studio interior utilizing immersive virtual reality (IVR) and wearable biofeedback technology. This study was a within-participant 2³ factorial design that included one baseline and eight IVR studio conditions. Participants experienced all conditions while reporting affects using the Self-Assessment Manikin (SAM) valence and arousal scales, electrodermal activity (EDA), and skin temperature (ST). Cybersickness was measured with the Simulator Sickness Questionnaire (SSQ) and presence was assessed using the Igroup Presence Questionnaire and Slater-Usoh-Steed presence measures (IPQ, SUS), while baseline anxiety (STAI) was controlled. The results demonstrated a significant primary influence of natural light on SAM valence ratings: conditions with natural light were evaluated as more pleasant than the non-variable and baseline condition, whereas interior vegetation and biomorphic form had smaller, context-dependent effects that were most evident when layered with natural light. Differences in SAM arousal ratings were modest and non-systematic. EDA did not differentiate, and ST showed only small shifts, indicating that during calm exploratory monitoring, subjective affect was more responsive. The circumplex findings guided to an activity-specific zoned interior rather than a single uniform design studio. Full article

Background: This study addresses a common challenge in music education: students’ limited emotional engagement during music listening. Objectives: This study compared two teaching methods—externally guided augmented reality (AR) integration and internally generated simulation—in terms of their neural and behavioral differences in guiding students’ visual mental imagery and influencing their musical affect processing. Methods: Using Chinese Pipa music appreciation as our experimental paradigm, we employed fNIRS hyperscanning to record inter-brain synchronization (IBS) during teacher–student interactions across three instructional conditions (AR group, n = 27; visual imagery group, n = 27; no-instruction group, n = 27), while simultaneously assessing students’ performance in music–emotion processing tasks (emotion recognition and experience). Results: At the behavioral level, both instructional methods significantly enhanced students’ ability to differentiate emotional valence in music compared to the control condition. Crucially, the AR approach demonstrated a unique advantage in augmenting emotional arousal. Neurally, both teaching methods significantly enhanced IBS in brain regions associated with emotion evaluation (lOFC) and imaginative reasoning (bilateral dlPFC). Beyond these shared neural correlates, AR instruction specifically engaged additional brain networks supporting social cognition (lFPC) and multisensory integration (rANG). Furthermore, we identified a significant positive correlation between lFPC-IBS and improved emotional arousal exclusively in the AR group. Conclusions: The visual imagery group primarily enhances emotional music processing through neural alignment in core emotional brain regions, while augmented reality instruction creates unique advantages by additionally activating brain networks associated with social cognition and cross-modal integration. This research provides neuroscientific evidence for the dissociable mechanisms through which different teaching approaches enhance music–emotion learning, offering important implications for developing evidence-based educational technologies. Full article

Amid growing “nature deficit” associated with urbanization and indoor living, flowering plants are increasingly used to support psychological restoration. Yet evidence on how floral color and structural morphology jointly shape restorative outcomes remains limited. This study employed a within-subjects, repeated-measures design, utilizing physiological instruments and psychological questionnaires to investigate the physiological and psychological restorative benefits of Hydrangea macrophylla and to quantify the differences in restorative effects across five colors (blue, pink, white, mauve, red), two inflorescence types (mophead, lacecap), and two petal structures (single, double). Twenty-eight healthy young adults viewed 15 live hydrangea stimuli under controlled laboratory conditions. Multimodal outcomes combined objective measures—eye-tracking and single-channel EEG—with subjective measures (SD; POMS). Hydrangea exposure significantly reduced negative mood, and color and structure exerted distinct and interactive effects on visual attention and arousal. Red and mauve elicited larger pupil diameters than white and pink, while lacecap inflorescences were associated with lower cognitive load and improved attentional recovery relative to mophead. Double-petaled forms showed greater attentional dispersion than single-petaled forms. Interactions indicated that morphology modulated color effects. The mauve lacecap double-flowered cultivar (M02) showed the strongest observed restorative potential within this sample. These findings highlight the importance of integrating color and structural cues when selecting flowering plants for restorative environments and horticultural therapy, and they motivate field-based replications with broader samples and higher-density physiology. Full article

Background/Objectives: Astrocytic redox-inflammatory signaling has been implicated in Parkinson’s disease (PD) pathology and may constrain hippocampal neurogenesis. We previously identified an astrocytic NOX4–MPO–OPN axis associated with impaired neurogenic capacity. Here, we tested whether a saffron-derived antioxidant (SDA; Crocus sativus extract) and Passiflora incarnata L. extract (PI) modulate this pathway in an MPTP-induced PD mouse model. Methods: Male C57BL/6J mice were randomized to Sham, MPTP, and treatment groups (n = 9/group for behavior; n = 4–5/group for histology/immunoblotting). SDA or PI (50 mg/kg/day, oral, 5 weeks) was administered, with resveratrol as a positive control. Behavioral, histological, and molecular analyses were performed by investigators blinded to group allocation where feasible. Results: SDA and PI were associated with reduced NOX4/MPO/OPN signals, mainly in GFAP-positive astrocytes, along with recovery of neurogenesis markers (Ki67, DCX, BrdU/NeuN) and synaptic markers (PSD95, synaptophysin), and improved motor performance. Mitochondrial and oxidative injury markers (TIM23, TOM20, OXPHOS subunits; 4-HNE) and apoptotic markers (Bax, cleaved caspase-3, Bcl-2) also shifted toward Sham levels. Given previous reports of Passiflora extracts’ sedative effects, we note that metabolic measures (body weight, food intake, and water intake) were similar across groups; however, specific tests for sedation or arousal were not conducted. Conclusions: These findings offer preclinical evidence that SDA and PI modulate redox-inflammatory and mitochondrial stress signatures and are associated with neurogenic, synaptic, and behavioral improvements in an acute MPTP model. Further validation in chronic/genetic PD models and pharmacokinetic/brain exposure studies will be necessary to confirm their translational potential. Full article

Early word learning is a critical milestone for children, yet autistic children often experience delays in language development. Social communication differences are a core feature of autism and may contribute to variability in learning experiences. Prior research has shown that word-level features such as iconicity, concreteness, and input frequency shape the timing of word learning, but less is known about the role of social word features. This study examined whether social word ratings predict when words tend to be acquired by autistic and non-autistic children. Social word ratings were examined as a predictor of word-level autistic and non-autistic acquisition normative data, while accounting for word input frequency. Regression analyses demonstrated that social ratings significantly predicted vocabulary acquisition, even after controlling for word frequency. Additional analyses demonstrated that socialness ratings continued to be a unique predictor of word acquisition when other affective features of words were included in the model (i.e., arousal and valence); this was also the case when iconicity and concreteness were included. Importantly, differences in group and interactions with social ratings and group were not statistically significant in any of the models. Lastly, the pattern of highly social words being acquired later in vocabulary development was strongest for nouns; the association was non-significant when examining verbs separately. Thus, in addition to previously studied word features like concreteness, imageability, and iconicity, social word features are predictive of vocabulary acquisition. These findings highlight an overlap in word features that influence learning in autistic and non-autistic children. Full article

This study aims to establish a method-integrative framework for emotion-oriented architectural image generation. The framework combines Stable Diffusion with targeted LoRA (Low-Rank Adaptation), a lightweight and parameter-efficient fine-tuning approach, together with ControlNet-based structural constraints, to examine how controllable design-element manipulations influence emotional responses. The methodology follows a closed-loop “generation–evaluation” workflow, with each LoRA module independently targeting a single design element. Guided by the relaxation–arousal emotional dimension, the framework is evaluated using subjective ratings and electroencephalogram (EEG) measures. Twenty-seven participants viewed six architectural space categories, each comprising four conditions (baseline, color, material, and form modification). EEG α/β power ratio (RAB) served as the primary neurophysiological marker of arousal. Statistical analysis indicated that LoRA-based modifications of design elements produced distinct emotional responses: color and material changes induced lower arousal, whereas changes in form elicited a bidirectional pattern involving relaxation and arousal. The right parietal P4 electrode site showed the most sensitive emotional response to design element changes, with consistent statistical significance. P4 is a human scalp EEG location associated with cortical activity related to visuospatial processing. Descriptive results suggested opposite directional effects with similar intensity trends; however, linear mixed-effects model (LMM) inference did not support significant group-level linear coupling, indicating individual variation. This study demonstrates the feasibility of emotion-guided architectural image generation, showing that controlled manipulation of color, material, and form can elicit measurable emotional responses in human brain activity. The findings provide a methodological basis for future multimodal, adaptive generative systems and offer a quantitative pathway for investigating the relationship between emotional states and architectural design elements. Full article

Development of new therapeutic approaches and strategies for common neuropsychiatric disorders, including Major Depressive Disorder, anxiety disorders, and Post-Traumatic Stress Disorder, represent a significant global health challenge. Recent research indicates that emotional dysregulation and persistent inflammation are closely linked and serve as key pathophysiological features of these conditions. Emotional dysregulation is mechanistically coupled to locus coeruleus and norepinephrine (LC-NE) or noradrenergic system activity. Stemming from chronic stress, persistently elevated activity of the LC-NE system leads to hypervigilance, anxious states, and depressed mood. Concurrently, these symptoms are marked by systemic inflammation as indicated by elevated pro-inflammatory cytokines, and central neuroinflammation indicated by microglial activation in brain regions and networks involved in mood regulation and emotional control. In turn, chronic inflammation increases sympathetic tone and LC-NE activity resulting in a vortex of psychoneuroimmunological dysfunction that worsens mental health. Transcutaneous auricular vagus nerve stimulation (taVNS) in a non-invasive neuromodulation method uniquely positioned to address both noradrenergic dysfunction and chronic inflammation in neuropsychiatric applications. Evidence spanning the past decade demonstrates taVNS works via two complementary mechanisms. An ascending pathway engages vagal afferents projecting to the LC-NE system in the brain stem, which has been shown to modulate cortical arousal, cognitive function, mood, and stress responses. Through descending circuits, taVNS also modulates the cholinergic anti-inflammatory pathway to suppress the production of pro-inflammatory cytokines like TNF-α and IL-6 mitigating poor health outcomes caused by inflammation. By enhancing both central brain function and peripheral immune responses, taVNS has shown significant potential for recalibrating perturbed affective-cognitive processing. The present article describes and discusses recent evidence suggesting that taVNS offers a promising network-based paradigm for restoring psychoneuroimmunological homeostasis in common neuropsychiatric conditions. Full article

Background/Objectives: Obstructive sleep apnea (OSA) is diagnosed using pulse oximetry, which is less accurate in patients with darker skin. Two hypopnea definitions are in use: the American Academy of Sleep Medicine allows either (A) a 30% airflow decrease with a 3% oxygen desaturation or EEG arousal (“3% Rule”) or (B) a 30% airflow decrease with a 4% oxygen desaturation (“4% Rule”). The Centers for Medicare and Medicaid Services and many payers use only the 4% Rule. We hypothesized that patients from racial minority groups with darker skin tones would be less likely to qualify for OSA treatment using the 4% Rule compared to the 3% Rule. A secondary aim was to examine sex disparities. Methods: We reviewed records of adults undergoing overnight sleep studies at an urban academic hospital. Demographics, medical history, and comorbidities were collected. Analyses controlled for age, sex, BMI, anxiety, depression, hypertension, COPD, and smoking. Results: A total of 1354 records were analyzed. We found no racial or sex disparities in the proportion of participants who met the 3% but not the 4% Rule. After controlling for covariates, no racial group differed from White participants in meeting only the 3% Rule. However, female participants were significantly less likely than males to meet the 4% Rule. Conclusions: Despite known limitations of pulse oximetry associated with skin tone, no racial differences in the diagnosis of OSA were seen in this cohort. However, female patients had lower odds of meeting the 4% Rule, suggesting a potential barrier to treatment. Full article