TMS Intensity and Focality Correlation with Coil Orientation at Three Non-Motor Regions

10.36227/techrxiv.15023409.v1 ◽

2021 ◽

Author(s):

Jose Gomez-Feria ◽

Mariano Fernandez-Corazza ◽

Juan Francisco Martin Rodriguez ◽

Pablo Mir

Keyword(s):

Current Density ◽

Posterior Parietal Cortex ◽

Computational Models ◽

Interindividual Variability ◽

Inferior Frontal Gyrus ◽

Brain Morphology ◽

Brain Anatomy ◽

Font Size ◽

Rough Approximation ◽

Density Methods

Objective: The aim of this study is to define the best transcranial magnetic stimulation (TMS) coil orientations for three clinically relevant brain areas (pre-supplementary motor area, inferior frontal gyrus, and posterior parietal cortex) by means of simulations in 12 realistic head models of current density. Methods: We computed the current densities generated by TMS in our three volumes of interest (VOI) that were delineated based on published atlases. We then analyzed the maximum intensity and spatial focality for the normal and absolute components of the current density considering different percentile thresholds. Lastly, we correlated these results with the different anatomical properties of our VOIs. Results: Overall, the spatial focality of the current density for the three VOIs varied depending on the coil’s orientation. There was major interindividual variability, and there was therefore no specific orientation that produced the best focality for all subjects. Further analysis showed that the differences in individual brain anatomy were related to the amount of focality achieved. In general, a larger percentage of sulci resulted in larger spatial focality. Moreover, larger normal current density intensity was achieved when positioning the coil axis perpendicular to the predominant orientations of the gyri of each ’s VOI. Conclusion: For a rough approximation, better coil orientations can be based on the individual’s specific brain morphology at the VOI. Moreover, TMS computational models should be employed to obtain better coil orientations in non-motor regions of interest. Significance: Finding better coil orientations in non-motor regions is a challenge in TMS and seeks to reduce interindividual variability. Our individualized TMS simulation pipeline leads to lesser interindividual variability in the focality, likely enhancing the efficacy of the stimulation and reducing the risk of stimulating adjacent, nontargeted areas. @font-face {font-family:Helvetica; panose-1:0 0 0 0 0 0 0 0 0 0; mso-font-charset:0; mso-generic-font-family:auto; mso-font-pitch:variable; mso-font-signature:-536870145 1342208091 0 0 415 0;}@font-face {font-family:"Cambria Math"; panose-1:2 4 5 3 5 4 6 3 2 4; mso-font-charset:0; mso-generic-font-family:roman; mso-font-pitch:variable; mso-font-signature:-536870145 1107305727 0 0 415 0;}@font-face {font-family:Calibri; panose-1:2 15 5 2 2 2 4 3 2 4; mso-font-charset:0; mso-generic-font-family:swiss; mso-font-pitch:variable; mso-font-signature:-1610611985 1073750139 0 0 159 0;}@font-face {font-family:Times; panose-1:0 0 5 0 0 0 0 2 0 0; mso-font-alt:Times; mso-font-charset:0; mso-generic-font-family:auto; mso-font-pitch:variable; mso-font-signature:-536870145 1342185562 0 0 415 0;}p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-unhide:no; mso-style-qformat:yes; mso-style-parent:""; margin-top:0cm; margin-right:0cm; margin-bottom:8.0pt; margin-left:0cm; line-height:107%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri",sans-serif; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:Calibri; mso-fareast-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi; mso-fareast-language:EN-US;}.MsoChpDefault {mso-style-type:export-only; mso-default-props:yes; font-size:11.0pt; mso-ansi-font-size:11.0pt; mso-bidi-font-size:11.0pt; font-family:"Calibri",sans-serif; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:Calibri; mso-fareast-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi; mso-fareast-language:EN-US;}.MsoPapDefault {mso-style-type:export-only; margin-bottom:8.0pt; line-height:107%;}div.WordSection1 {page:WordSection1;}

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Effects of eight neuropsychiatric copy number variants on human brain structure

Translational Psychiatry ◽

10.1038/s41398-021-01490-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Claudia Modenato ◽

Kuldeep Kumar ◽

Clara Moreau ◽

Sandra Martin-Brevet ◽

Guillaume Huguet ◽

...

Keyword(s):

Copy Number ◽

Copy Number Variants ◽

Principal Component ◽

Brain Morphology ◽

Brain Anatomy ◽

Brain Morphometry ◽

Supplementary Motor Cortex ◽

Psychiatric Conditions ◽

Latent Dimension ◽

Mirror Effects

AbstractMany copy number variants (CNVs) confer risk for the same range of neurodevelopmental symptoms and psychiatric conditions including autism and schizophrenia. Yet, to date neuroimaging studies have typically been carried out one mutation at a time, showing that CNVs have large effects on brain anatomy. Here, we aimed to characterize and quantify the distinct brain morphometry effects and latent dimensions across 8 neuropsychiatric CNVs. We analyzed T1-weighted MRI data from clinically and non-clinically ascertained CNV carriers (deletion/duplication) at the 1q21.1 (n = 39/28), 16p11.2 (n = 87/78), 22q11.2 (n = 75/30), and 15q11.2 (n = 72/76) loci as well as 1296 non-carriers (controls). Case-control contrasts of all examined genomic loci demonstrated effects on brain anatomy, with deletions and duplications showing mirror effects at the global and regional levels. Although CNVs mainly showed distinct brain patterns, principal component analysis (PCA) loaded subsets of CNVs on two latent brain dimensions, which explained 32 and 29% of the variance of the 8 Cohen’s d maps. The cingulate gyrus, insula, supplementary motor cortex, and cerebellum were identified by PCA and multi-view pattern learning as top regions contributing to latent dimension shared across subsets of CNVs. The large proportion of distinct CNV effects on brain morphology may explain the small neuroimaging effect sizes reported in polygenic psychiatric conditions. Nevertheless, latent gene brain morphology dimensions will help subgroup the rapidly expanding landscape of neuropsychiatric variants and dissect the heterogeneity of idiopathic conditions.

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Brain morphology predicts social intelligence in wild cleaner fish

Nature Communications ◽

10.1038/s41467-020-20130-2 ◽

2020 ◽

Vol 11 (1) ◽

Author(s):

Zegni Triki ◽

Yasmin Emery ◽

Magda C. Teles ◽

Rui F. Oliveira ◽

Redouan Bshary

Keyword(s):

Social Intelligence ◽

Brain Plasticity ◽

Decision Rules ◽

Brain Morphology ◽

Brain Anatomy ◽

Environmental Complexity ◽

Learning Abilities ◽

Cleaner Fish ◽

High Performing ◽

Selective Pressures

AbstractIt is generally agreed that variation in social and/or environmental complexity yields variation in selective pressures on brain anatomy, where more complex brains should yield increased intelligence. While these insights are based on many evolutionary studies, it remains unclear how ecology impacts brain plasticity and subsequently cognitive performance within a species. Here, we show that in wild cleaner fish (Labroides dimidiatus), forebrain size of high-performing individuals tested in an ephemeral reward task covaried positively with cleaner density, while cerebellum size covaried negatively with cleaner density. This unexpected relationship may be explained if we consider that performance in this task reflects the decision rules that individuals use in nature rather than learning abilities: cleaners with relatively larger forebrains used decision-rules that appeared to be locally optimal. Thus, social competence seems to be a suitable proxy of intelligence to understand individual differences under natural conditions.

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Dissecting the midlife crisis: disentangling social, personality and demographic determinants in social brain anatomy

Communications Biology ◽

10.1038/s42003-021-02206-x ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Hannah Kiesow ◽

Lucina Q. Uddin ◽

Boris C. Bernhardt ◽

Joseph Kable ◽

Danilo Bzdok

Keyword(s):

Brain Regions ◽

Interindividual Variation ◽

Brain Morphology ◽

Brain Anatomy ◽

Leadership Roles ◽

Social Brain ◽

Aging Parents ◽

Health Satisfaction ◽

Midlife Transitions ◽

Fully Bayesian

AbstractIn any stage of life, humans crave connection with other people. In midlife, transitions in social networks can relate to new leadership roles at work or becoming a caregiver for aging parents. Previous neuroimaging studies have pinpointed the medial prefrontal cortex (mPFC) to undergo structural remodelling during midlife. Social behavior, personality predisposition, and demographic profile all have intimate links to the mPFC according in largely disconnected literatures. Here, we explicitly estimated their unique associations with brain structure using a fully Bayesian framework. We weighed against each other a rich collection of 40 UK Biobank traits with their interindividual variation in social brain morphology in ~10,000 middle-aged participants. Household size and daily routines showed several of the largest effects in explaining variation in social brain regions. We also revealed male-biased effects in the dorsal mPFC and amygdala for job income, and a female-biased effect in the ventral mPFC for health satisfaction.

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Attentional bias to threat and gray mater volume morphology in high anxious individuals

10.1101/2020.10.20.346981 ◽

2020 ◽

Author(s):

Joshua M. Carlson ◽

Lin Fang

Keyword(s):

Attentional Bias ◽

Parietal Cortex ◽

Gray Matter ◽

Posterior Parietal Cortex ◽

Gray Matter Volume ◽

Anterior Cingulate ◽

Brain Morphology ◽

Matter Volume ◽

Posterior Parietal ◽

The Right

AbstractIn a sample of highly anxious individuals, the relationship between gray matter volume brain morphology and attentional bias to threat was assessed. Participants performed a dot-probe task of attentional bias to threat and gray matter volume was acquired from whole brain structural T1-weighted MRI scans. The results replicate previous findings in unselected samples that elevated attentional bias to threat is linked to greater gray matter volume in the anterior cingulate cortex, middle frontal gyrus, and striatum. In addition, we provide novel evidence that elevated attentional bias to threat is associated with greater gray matter volume in the right posterior parietal cortex, cerebellum, and other distributed regions. Lastly, exploratory analyses provide initial evidence that distinct sub-regions of the right posterior parietal cortex may contribute to attentional bias in a sex-specific manner. Our results illuminate how differences in gray matter volume morphology relate to attentional bias to threat in anxious individuals. This knowledge could inform neurocognitive models of anxiety-related attentional bias to threat and targets of neuroplasticity in anxiety interventions such as attention bias modification.

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Obstetric complications, treatment response and brain morphology in adult-onset and early-onset males with schizophrenia

Psychological Medicine ◽

10.1017/s0033291797006405 ◽

1998 ◽

Vol 28 (3) ◽

pp. 645-653 ◽

Cited By ~ 12

Author(s):

G. N. SMITH ◽

L. C. KOPALA ◽

J. S. LAPOINTE ◽

G. W. MacEWAN ◽

S. ALTMAN ◽

...

Keyword(s):

Treatment Response ◽

Early Onset ◽

Age At Onset ◽

Obstetric Complications ◽

Brain Morphology ◽

Brain Anatomy ◽

Adult Onset ◽

Course Of Illness ◽

Illness Onset ◽

Duration Of Illness

Background. Substantial variability in age at onset of illness and course of illness exists between patients with schizophrenia. Recent studies suggest that age at illness onset may be useful in defining biologically and clinically distinct subgroups of patients.Methods. Two hundred and ten males with schizophrenia were classified as early-onset or adult-onset according to their age at first hospitalization. Birth history, clinical functioning and treatment response was assessed in a subgroup of patients. Brain anatomy was assessed from CT scans in all patients and in 32 non-psychiatric control subjects.Results. Patients with an early-onset were likely to have a history of obstetric complications, a poor response to neuroleptic treatment, and showed no relationship between ventricle size and duration of illness. Adult-onset patients were less likely to have obstetric complications, more likely to respond to treatment in the first years of illness, and showed an association between brain structure and duration of illness.Conclusions. The distinction between early- and adult-onset patients may have important aetiological and treatment implications.

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Environmentally induced changes to brain morphology predict cognitive performance

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2017.0287 ◽

2018 ◽

Vol 373 (1756) ◽

pp. 20170287 ◽

Cited By ~ 10

Author(s):

Thomas W. Pike ◽

Michael Ramsey ◽

Anna Wilkinson

Keyword(s):

Cognitive Performance ◽

Optic Tectum ◽

Relative Size ◽

Brain Regions ◽

Cognitive Capacity ◽

Brain Morphology ◽

Chemical Information ◽

Brain Anatomy ◽

Short Term ◽

Olfactory Bulbs

The relationship between the size and structure of a species' brain and its cognitive capacity has long interested scientists. Generally, this work relates interspecific variation in brain anatomy with performance on a variety of cognitive tasks. However, brains are known to show considerable short-term plasticity in response to a range of social, ecological and environmental factors. Despite this, we have a remarkably poor understanding of how this impacts on an animal's cognitive performance. Here, we non-invasively manipulated the relative size of brain regions associated with processing visual and chemical information in fish (the optic tectum and olfactory bulbs, respectively). We then tested performance in a cognitive task in which information from the two sensory modalities was in conflict. Although the fish could effectively use both visual and chemical information if presented in isolation, when they received cues from both modalities simultaneously, those with a relatively better developed optic tectum showed a greater reliance on visual information, while individuals with relatively better developed olfactory bulbs showed a greater reliance on chemical information. These results suggest that short-term changes in brain structure, possibly resulting from an attempt to minimize the costs of developing unnecessary but energetically expensive brain regions, may have marked effects on cognitive performance. This article is part of the theme issue ‘Causes and consequences of individual differences in cognitive abilities’.

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Audiovisual stimulus-driven contributions to spatial orienting in ecologically valid situations: An fMRI study

Seeing and Perceiving ◽

10.1163/187847612x646389 ◽

2012 ◽

Vol 25 (0) ◽

pp. 16

Author(s):

Davide Nardo ◽

Valerio Santangelo ◽

Emiliano Macaluso

Keyword(s):

Eye Movements ◽

Parietal Cortex ◽

Posterior Parietal Cortex ◽

Computational Models ◽

Spatial Relationship ◽

Visual Saliency ◽

Occipital Cortex ◽

Audiovisual Stimulus ◽

Spatial Orienting ◽

Posterior Parietal

Mechanisms of audiovisual attention have been extensively investigated, yet little is known about their functioning in ecologically-valid situations. Here, we investigated brain activity associated with audiovisual stimulus-driven attention using naturalistic stimuli. We created 120 short videos (2.5 s) showing scenes of everyday life. Each video included a visual event comprising a lateralized (left/right) increase in visual saliency (e.g., an actor moving an object), plus a co-occurring sound either on the same or the opposite side of space. Subjects viewed the videos with/without the associated sounds, and either in covert (central fixation) or overt (eye-movements allowed) viewing conditions. For each stimulus, we used computational models (‘saliency maps’) to characterize auditory and visual stimulus-driven signals, and eye-movements (recorded in free viewing) as a measure of the efficacy of these signals for spatial orienting. Results showed that visual saliency modulated activity in the occipital cortex contralateral to the visual event; while auditory saliency modulated activity in the superior temporal gyrus bilaterally. In the posterior parietal cortex activity increased with increasing auditory saliency, but only when the auditory stimulus was on the same side as the visual event. The efficacy of the stimulus-driven signals modulated activity in the visual cortex. We conclude that: (1) audiovisual attention can be successfully investigated in real-like situations; (2) activity in sensory areas reflects a combination of stimulus-driven signals (saliency) and their efficacy for spatial orienting; (3) posterior parietal cortex processes auditory input as a function of its spatial relationship with the visual input.

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Gender Differences in Brain Serotonin Synthesis in Individuals with Major Depressive Disorder: A A-[11C]MT Pet Imaging Study

European Psychiatry ◽

10.1016/s0924-9338(09)70914-9 ◽

2009 ◽

Vol 24 (S1) ◽

pp. 1-1 ◽

Cited By ~ 1

Author(s):

B.N. Frey ◽

I. Skelin ◽

Y. Sakai ◽

M. Nishikawa ◽

M. Diksic

Keyword(s):

Gender Differences ◽

Major Depressive Disorder ◽

Depressive Disorder ◽

Inferior Frontal Gyrus ◽

Anterior Cingulate ◽

Brain Morphology ◽

Brain Serotonin ◽

Serotonin Synthesis ◽

Major Depressive ◽

Men And Women

Objective:Women are at higher risk than men to develop major depressive disorder (MDD), but the mechanisms underlying the higher risk for MDD in women are unknown. There is a wealth of data showing gender differences in brain morphology and function. In addition, preclinical studies have demonstrated reciprocal relationships between ovarian hormones and serotonin neurotransmission. Thus, gender differences in brain serotonin neurotransmission are potential underlying mechanisms. In the present study, we compared normalized α-[11C]methyl-L-tryptophan brain trapping constant (α-[11C]MTrp K*; ml/g/min), an index of serotonin synthesis, between men and women with MDD.Method:α-[11C]MTrp K* was measured in 25 medication-free individuals with MDD (13 females and 12 males) using positron emission tomography. Comparisons of normalized α-[11C]MTrp K* values between men and women were conducted at the voxel level using Statistical Parametric Mapping 2 (SPM2) analysis.Results:Women with MDD displayed significantly higher (p< 0.005) normalized α-[11C]MTrp K* than men in the inferior frontal gyrus, anterior cingulate cortex (ACC), parahippocampal gyrus, precuneus and superior parietal lobule, and occipital lingual gyrus.Conclusions:This finding suggests that depressive women have higher serotonin synthesis in multiple regions of the prefrontal cortex and limbic system involved with mood regulation. Gender differences in brain serotonin synthesis may be associated with higher risk for MDD in women because extra levels of tissue 5-HT could create non-physiological connections influencing changes in mood.

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Working Memory Retrieval: Contributions of the Left Prefrontal Cortex, the Left Posterior Parietal Cortex, and the Hippocampus

Journal of Cognitive Neuroscience ◽

10.1162/jocn.2008.21016 ◽

2009 ◽

Vol 21 (3) ◽

pp. 581-593 ◽

Cited By ~ 90

Author(s):

Ilke Öztekin ◽

Brian McElree ◽

Bernhard P. Staresina ◽

Lila Davachi

Keyword(s):

Working Memory ◽

Parietal Cortex ◽

Posterior Parietal Cortex ◽

Inferior Frontal Gyrus ◽

Long Term Memory ◽

Term Memory ◽

Focal Attention ◽

Left Posterior ◽

Posterior Parietal

Functional magnetic resonance imaging was used to identify regions involved in working memory (WM) retrieval. Neural activation was examined in two WM tasks: an item recognition task, which can be mediated by a direct-access retrieval process, and a judgment of recency task that requires a serial search. Dissociations were found in the activation patterns in the hippocampus and in the left inferior frontal gyrus (LIFG) when the probe contained the most recently studied serial position (where a test probe can be matched to the contents of focal attention) compared to when it contained all other positions (where retrieval is required). The data implicate the hippocampus and the LIFG in retrieval from WM, complementing their established role in long-term memory. Results further suggest that the left posterior parietal cortex (LPPC) supports serial retrieval processes that are often required to recover temporal order information. Together, these data suggest that the LPPC, the LIFG, and the hippocampus collectively support WM retrieval. Critically, the reported findings support accounts that posit a distinction between representations maintained in and outside of focal attention, but are at odds with traditional dual-store models that assume distinct mechanisms for short- and long-term memory representations.

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