The Menstrual Cycle Modulates Whole-Brain Turbulent Dynamics

Brain dynamics have recently been shown to be modulated by rhythmic changes in female sex hormone concentrations across an entire menstrual cycle. However, many questions remain regarding the specific differences in information processing across spacetime between the two main follicular and luteal phases in the menstrual cycle. Using a novel turbulent dynamic framework, we studied whole-brain information processing across spacetime scales (i.e., across long and short distances in the brain) in two open-source, dense-sampled resting-state datasets. A healthy naturally cycling woman in her early twenties was scanned over 30 consecutive days during a naturally occurring menstrual cycle and under a hormonal contraceptive regime. Our results indicated that the luteal phase is characterized by significantly higher information transmission across spatial scales than the follicular phase. Furthermore, we found significant differences in turbulence levels between the two phases in brain regions belonging to the default mode, salience/ventral attention, somatomotor, control, and dorsal attention networks. Finally, we found that changes in estradiol and progesterone concentrations modulate whole-brain turbulent dynamics in long distances. In contrast, we reported no significant differences in information processing measures between the active and placebo phases in the hormonal contraceptive study. Overall, the results demonstrate that the turbulence framework is able to capture differences in whole-brain turbulent dynamics related to ovarian hormones and menstrual cycle stages.

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Conceptual disorganization and redistribution of resting state cortical hubs in untreated first episode psychosis: A 7T MRI study

10.31234/osf.io/rzvby ◽

2020 ◽

Author(s):

Avyarthana Dey ◽

Kara Dempster ◽

Michael Mackinley ◽

Peter Jeon ◽

Tushar Das ◽

...

Keyword(s):

Negative Symptoms ◽

Superior Temporal Gyrus ◽

Brain Regions ◽

First Episode Psychosis ◽

Cortical Reorganization ◽

First Episode ◽

Formal Thought Disorder ◽

Whole Brain ◽

Episode Psychosis ◽

Positive And Negative Symptoms

Background:Network level dysconnectivity has been studied in positive and negative symptoms of schizophrenia. Conceptual disorganization (CD) is a symptom subtype which predicts impaired real-world functioning in psychosis. Systematic reviews have reported aberrant connectivity in formal thought disorder, a construct related to CD. However, no studies have investigated whole-brain functional correlates of CD in psychosis. We sought to investigate brain regions explaining the severity of CD in patients with first-episode psychosis (FEPs) compared with healthy controls (HCs).Methods:We computed whole-brain binarized degree centrality maps of 31 FEPs, 25 HCs and characterized the patterns of network connectivity in the two groups. In FEPs, we related these findings to the severity of CD. We also studied the effect of positive and negative symptoms on altered network connectivity.Results:Compared to HCs, reduced hubness of a right superior temporal gyrus (rSTG) cluster was observed in the FEPs. In patients exhibiting high CD, increased hubness of a medial superior parietal (mSPL) cluster was observed, compared to patients exhibiting low CD. These two regions were strongly correlated with CD scores but not with other symptom scores.Discussion:Our observations are congruent with previous findings of reduced but not increased hubness. We observed increased hubness of mSPL suggesting that cortical reorganization occurs to provide alternate routes for information transfer.Conclusion:These findings provide insight into the underlying neural processes mediating the presentation of symptoms in untreated FEP. A longitudinal tracking of the symptom course will be useful to assess the mechanisms underlying these compensatory changes.

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Social exclusion increases the executive function of attention networks

Scientific Reports ◽

10.1038/s41598-021-86385-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Huoyin Zhang ◽

Shiyunmeng Zhang ◽

Jiachen Lu ◽

Yi Lei ◽

Hong Li

Keyword(s):

Social Exclusion ◽

Executive Control ◽

Brain Regions ◽

Negative Influence ◽

Future Research ◽

Research Attention ◽

Attention Network ◽

Attention Networks ◽

The Social ◽

And Control

AbstractPrevious studies in humans have shown that brain regions activating social exclusion overlap with those related to attention. However, in the context of social exclusion, how does behavioral monitoring affect individual behavior? In this study, we used the Cyberball game to induce the social exclusion effect in a group of participants. To explore the influence of social exclusion on the attention network, we administered the Attention Network Test (ANT) and compared results for the three subsystems of the attention network (orienting, alerting, and executive control) between exclusion (N = 60) and inclusion (N = 60) groups. Compared with the inclusion group, the exclusion group showed shorter overall response time and better executive control performance, but no significant differences in orienting or alerting. The excluded individuals showed a stronger ability to detect and control conflicts. It appears that social exclusion does not always exert a negative influence on individuals. In future research, attention to network can be used as indicators of social exclusion. This may further reveal how social exclusion affects individuals' psychosomatic mechanisms.

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Influence of Menstrual Cycle or Hormonal Contraceptive Phase on Energy Intake and Metabolic Hormones—A Pilot Study

Endocrines ◽

10.3390/endocrines2020008 ◽

2021 ◽

Vol 2 (2) ◽

pp. 79-90

Author(s):

Johanna K. Ihalainen ◽

Ida Löfberg ◽

Anna Kotkajuuri ◽

Heikki Kyröläinen ◽

Anthony C. Hackney ◽

...

Keyword(s):

Menstrual Cycle ◽

Energy Intake ◽

Hormonal Contraceptive ◽

Group Differences ◽

Metabolic Hormones ◽

Recreational Athletes ◽

Total Ghrelin ◽

17Β Estradiol ◽

The Mean ◽

And Training

Sex hormones are suggested to influence energy intake (EI) and metabolic hormones. This study investigated the influence of menstrual cycle (MC) and hormonal contraceptive (HC) cycle phases on EI, energy availability (EA), and metabolic hormones in recreational athletes (eumenorrheic, NHC = 15 and monophasic HC-users, CHC = 9). In addition, 72-h dietary and training logs were collected in addition to blood samples, which were analyzed for 17β-estradiol (E2), progesterone (P4), leptin, total ghrelin, insulin, and tri-iodothyronine (T3). Measurements were completed at four time-points (phases): Bleeding, mid-follicular (FP)/active 1, ovulation (OVU)/active 2, mid-luteal (LP)/inactive in NHC/CHC, respectively. As expected, E2 and P4 fluctuated significantly in NHC (p < 0.05) and remained stable in CHC. In NHC, leptin increased significantly between bleeding and ovulation (p = 0.030) as well as between FP and OVU (p = 0.022). No group differences in other measured hormones were observed across the MC and HC cycle. The mean EI and EA were similar between phases, with no significant differences observed in macronutrient intake over either the MC or HC. While the MC phase might have a small, but statistically significant effect on leptin, the findings of the present study suggest that the MC or HC phase does not significantly alter ad libitum EI or EA in recreational athletes.

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Haemodynamic responses to psychosocial stress during the menstrual cycle

Clinical Science ◽

10.1042/cs0810017 ◽

1991 ◽

Vol 81 (1) ◽

pp. 17-22 ◽

Cited By ~ 21

Author(s):

Karin Manhem ◽

Christina Jern ◽

Martin Pilhall ◽

Guy Shanks ◽

Sverker Jern

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Menstrual Cycle ◽

Systolic Blood Pressure ◽

Psychosocial Stress ◽

Mental Stress ◽

Luteal Phase ◽

Follicular Phase ◽

Two Phases ◽

Plasma Catecholamine Concentrations

1. The haemodynamic effects of hormonal changes during the menstrual cycle were examined in 11 normotensive women (age 20–46 years). The subjects were studied on days 2–8 (follicular phase) and days 18–26 (luteal phase) in a randomized order. A standardized mental stress test and a 24 h recording of ambulatory blood pressure and heart rate were performed. 2. Pre-stress resting levels of heart rate and blood pressure were similar during the two phases of the menstrual cycle. 3. During mental stress, the heart rate response was significantly greater during the luteal phase than during the follicular phase (14.7 versus 9.7 beats/min; P < 0.05). 4. Blood pressure, plasma catecholamine concentrations and subjective stress experience increased significantly in response to stress, without any significant differences between the two phases. 5. During 24 h ambulatory monitoring, higher levels of systolic blood pressure and heart rate were observed in the luteal phase than in the follicular phase (P < 0.005 and P < 0.0001, respectively). 6. These data indicate that cyclic variations in female sex hormones not only affect systolic blood pressure and heart rate, but also alter the haemodynamic responses to psychosocial stress.

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Cerebrovascular responses of the rat brain to noxious stimuli as examined by functional near-infrared whole brain imaging

Journal of Neurophysiology ◽

10.1152/jn.00050.2011 ◽

2012 ◽

Vol 107 (10) ◽

pp. 2853-2865 ◽

Cited By ~ 6

Author(s):

Ji-Wei He ◽

Fenghua Tian ◽

Hanli Liu ◽

Yuan Bo Peng

Keyword(s):

Brain Imaging ◽

Near Infrared ◽

Small Animal ◽

Nir Spectroscopy ◽

Brain Regions ◽

Anterior Cingulate ◽

Hemodynamic Changes ◽

Whole Brain ◽

Brain Hemodynamics

While near-infrared (NIR) spectroscopy has been increasingly used to detect stimulated brain activities with an advantage of dissociating regional oxy- and deoxyhemoglobin concentrations simultaneously, it has not been utilized much in pain research. Here, we investigated and demonstrated the feasibility of using this technique to obtain whole brain hemodynamics in rats and speculated on the functional relevance of the NIR-based hemodynamic signals during pain processing. NIR signals were emitted and collected using a 26-optodes array on rat's dorsal skull surface after the removal of skin. Following the subcutaneous injection of formalin (50 μl, 3%) into a hindpaw, several isolable brain regions showed hemodynamic changes, including the anterior cingulate cortex, primary/secondary somatosensory cortexes, thalamus, and periaqueductal gray ( n = 6). Time courses of hemodynamic changes in respective regions matched with the well-documented biphasic excitatory response. Surprisingly, an atypical pattern (i.e., a decrease in oxyhemoglobin concentration with a concomitant increase in deoxyhemoglobin concentration) was seen in phase II. In a separate group of rats with innocuous brush and noxious pinch of the same area ( n = 11), results confirmed that the atypical pattern occurred more likely in the presence of nociception than nonpainful stimulation, suggesting it as a physiological substrate when the brain processes pain. In conclusion, the NIR whole brain imaging provides a useful alternative to study pain in vivo using small-animal models. Our results support the notion that neurovascular response patterns depend on stimuli, bringing attention to the interpretation of vascular-based neuroimaging data in studies of pain.

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Increased sensitivity to strong perturbations in a whole-brain model of LSD

10.1101/2021.01.05.425415 ◽

2021 ◽

Author(s):

Beatrice M. Jobst ◽

Selen Atasoy ◽

Adrián Ponce-Alvarez ◽

Ana Sanjuán ◽

Leor Roseman ◽

...

Keyword(s):

Magnetic Resonance Imaging ◽

External Perturbation ◽

Brain Regions ◽

Lysergic Acid ◽

Functional Magnetic Resonance ◽

Resonance Imaging ◽

Whole Brain ◽

Response Diversity ◽

Brain States ◽

The Brain

AbstractLysergic acid diethylamide (LSD) is a potent psychedelic drug, which has seen a revival in clinical and pharmacological research within recent years. Human neuroimaging studies have shown fundamental changes in brain-wide functional connectivity and an expansion of dynamical brain states, thus raising the question about a mechanistic explanation of the dynamics underlying these alterations. Here, we applied a novel perturbational approach based on a whole-brain computational model, which opens up the possibility to externally perturb different brain regions in silico and investigate differences in dynamical stability of different brain states, i.e. the dynamical response of a certain brain region to an external perturbation. After adjusting the whole-brain model parameters to reflect the dynamics of functional magnetic resonance imaging (fMRI) BOLD signals recorded under the influence of LSD or placebo, perturbations of different brain areas were simulated by either promoting or disrupting synchronization in the regarding brain region. After perturbation offset, we quantified the recovery characteristics of the brain area to its basal dynamical state with the Perturbational Integration Latency Index (PILI) and used this measure to distinguish between the two brain states. We found significant changes in dynamical complexity with consistently higher PILI values after LSD intake on a global level, which indicates a shift of the brain’s global working point further away from a stable equilibrium as compared to normal conditions. On a local level, we found that the largest differences were measured within the limbic network, the visual network and the default mode network. Additionally, we found a higher variability of PILI values across different brain regions after LSD intake, indicating higher response diversity under LSD after an external perturbation. Our results provide important new insights into the brain-wide dynamical changes underlying the psychedelic state - here provoked by LSD intake - and underline possible future clinical applications of psychedelic drugs in particular psychiatric disorders.HighlightsNovel offline perturbational method applied on functional magnetic resonance imaging (fMRI) data under the effect of lysergic acid diethylamide (LSD)Shift of brain’s global working point to more complex dynamics after LSD intakeConsistently longer recovery time after model perturbation under LSD influenceStrongest effects in resting state networks relevant for psychedelic experienceHigher response diversity across brain regions under LSD influence after an external in silico perturbation

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White-matter free-water diffusion MRI in schizophrenia: a systematic review and meta-analysis

Neuropsychopharmacology ◽

10.1038/s41386-022-01272-x ◽

2022 ◽

Author(s):

Inês Carreira Figueiredo ◽

Faith Borgan ◽

Ofer Pasternak ◽

Federico E. Turkheimer ◽

Oliver D. Howes

Keyword(s):

White Matter ◽

Healthy Volunteers ◽

Diffusion Mri ◽

Clinical Symptoms ◽

Free Water ◽

Brain Regions ◽

Water Levels ◽

First Episode ◽

Whole Brain ◽

Illness Duration

AbstractWhite-matter abnormalities, including increases in extracellular free-water, are implicated in the pathophysiology of schizophrenia. Recent advances in diffusion magnetic resonance imaging (MRI) enable free-water levels to be indexed. However, the brain levels in patients with schizophrenia have not yet been systematically investigated. We aimed to meta-analyse white-matter free-water levels in patients with schizophrenia compared to healthy volunteers. We performed a literature search in EMBASE, MEDLINE, and PsycINFO databases. Diffusion MRI studies reporting free-water in patients with schizophrenia compared to healthy controls were included. We investigated the effect of demographic variables, illness duration, chlorpromazine equivalents of antipsychotic medication, type of scanner, and clinical symptoms severity on free-water measures. Ten studies, including five of first episode of psychosis have investigated free-water levels in schizophrenia, with significantly higher levels reported in whole-brain and specific brain regions (including corona radiata, internal capsule, superior and inferior longitudinal fasciculus, cingulum bundle, and corpus callosum). Six studies, including a total of 614 participants met the inclusion criteria for quantitative analysis. Whole-brain free-water levels were significantly higher in patients relative to healthy volunteers (Hedge’s g = 0.38, 95% confidence interval (CI) 0.07–0.69, p = 0.02). Sex moderated this effect, such that smaller effects were seen in samples with more females (z = −2.54, p < 0.05), but antipsychotic dose, illness duration and symptom severity did not. Patients with schizophrenia have increased free-water compared to healthy volunteers. Future studies are necessary to determine the pathological sources of increased free-water, and its relationship with illness duration and severity.

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Hebbian plasticity in parallel synaptic pathways: A circuit mechanism for systems memory consolidation

PLoS Computational Biology ◽

10.1371/journal.pcbi.1009681 ◽

2021 ◽

Vol 17 (12) ◽

pp. e1009681

Author(s):

Michiel W. H. Remme ◽

Urs Bergmann ◽

Denis Alevi ◽

Susanne Schreiber ◽

Henning Sprekeler ◽

...

Keyword(s):

Memory Consolidation ◽

Computational Models ◽

Hippocampal Formation ◽

Spatial Scales ◽

Single Cells ◽

Brain Regions ◽

Quantitative Agreement ◽

Long Term Memory ◽

Hebbian Plasticity ◽

Mathematical Analyses

Systems memory consolidation involves the transfer of memories across brain regions and the transformation of memory content. For example, declarative memories that transiently depend on the hippocampal formation are transformed into long-term memory traces in neocortical networks, and procedural memories are transformed within cortico-striatal networks. These consolidation processes are thought to rely on replay and repetition of recently acquired memories, but the cellular and network mechanisms that mediate the changes of memories are poorly understood. Here, we suggest that systems memory consolidation could arise from Hebbian plasticity in networks with parallel synaptic pathways—two ubiquitous features of neural circuits in the brain. We explore this hypothesis in the context of hippocampus-dependent memories. Using computational models and mathematical analyses, we illustrate how memories are transferred across circuits and discuss why their representations could change. The analyses suggest that Hebbian plasticity mediates consolidation by transferring a linear approximation of a previously acquired memory into a parallel pathway. Our modelling results are further in quantitative agreement with lesion studies in rodents. Moreover, a hierarchical iteration of the mechanism yields power-law forgetting—as observed in psychophysical studies in humans. The predicted circuit mechanism thus bridges spatial scales from single cells to cortical areas and time scales from milliseconds to years.

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Lynn_etal_MathSkills_CPM_Preprint_V1_05July2021

10.31234/osf.io/xp79b ◽

2021 ◽

Author(s):

Andrew Lynn ◽

Eric D. Wilkey ◽

Gavin Price

Keyword(s):

Functional Connectivity ◽

Predictive Modeling ◽

Brain Connectivity ◽

Network Connectivity ◽

Brain Regions ◽

Math Skills ◽

Whole Brain ◽

Building Models ◽

State Dependent ◽

Brain Behavior

The human brain comprises multiple canonical networks, several of which are distributed across frontal, parietal, and temporooccipital regions. Studies report both positive and negative correlations between children’s math skills and the strength of functional connectivity among these regions during math-related tasks and at rest. Yet, it is unclear how the relation between children’s math skills and functional connectivity map onto patterns of distributed whole-brain connectivity, canonical network connectivity, and whether these relations are consistent across different task-states. We used connectome-based predictive modeling to test whether functional connectivity during number comparison and at rest predicts children’s math skills (N=31, Mage=9.21years) using distributed whole-brain connections versus connections among canonical networks. We found that weaker connectivity distributed across the whole brain and weaker connectivity between key math-related brain regions in specific canonical networks predicts better math skills in childhood. The specific connections predicting math skills, and whether they were distributed or mapped onto canonical networks, varied between tasks, suggesting that state-dependent rather than trait-level functional network architectures support children’s math skills. Furthermore, the current predictive modeling approach moves beyond brain-behavior correlations and toward building models of brain connectivity that may eventually aid in predicting future math skills.

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Brain regions associated with visual cues are important for bird migration

Biology Letters ◽

10.1098/rsbl.2015.0678 ◽

2015 ◽

Vol 11 (11) ◽

pp. 20150678 ◽

Cited By ~ 11

Author(s):

Orsolya Vincze ◽

Csongor I. Vágási ◽

Péter L. Pap ◽

Gergely Osváth ◽

Anders Pape Møller

Keyword(s):

Visual Cues ◽

Optic Lobe ◽

Brain Size ◽

Relative Size ◽

Bird Species ◽

Interspecific Variation ◽

Brain Regions ◽

Long Distance ◽

Migration Distance ◽

Whole Brain

Long-distance migratory birds have relatively smaller brains than short-distance migrants or residents. Here, we test whether reduction in brain size with migration distance can be generalized across the different brain regions suggested to play key roles in orientation during migration. Based on 152 bird species, belonging to 61 avian families from six continents, we show that the sizes of both the telencephalon and the whole brain decrease, and the relative size of the optic lobe increases, while cerebellum size does not change with increasing migration distance. Body mass, whole brain size, optic lobe size and wing aspect ratio together account for a remarkable 46% of interspecific variation in average migration distance across bird species. These results indicate that visual acuity might be a primary neural adaptation to the ecological challenge of migration.

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