我々は、設計上の有意義な議論とコメントのアルドRustichiniに感謝します。 ILとPWGにNIA助成R01-AG033406から研究助成を受けた。

<ol>
	<li>Glimcher, P. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Understanding+risk:+a+guide+for+the+perplexed.">Understanding risk: a guide for the perplexed.</a> Cogn. Affect Behav. Neurosci. 8, 348-354 (2008).</li><li>Camerer, C., Weber, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recent+Developments+in+Modeling+Preferences+-+Uncertainty+and+Ambiguity.">Recent Developments in Modeling Preferences - Uncertainty and Ambiguity.</a> Journal of Risk and Uncertainty. 5, 325-370 (1992).</li><li>Holt, C. A., Laury, S. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Risk+aversion+and+incentive+effects.">Risk aversion and incentive effects.</a> Am. Econ. Rev. 92, 1644-1655 (2002).</li><li>Levy, I., Snell, J., Nelson, A. J., Rustichini, A., Glimcher, P. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neural+representation+of+subjective+value+under+risk+and+ambiguity.">Neural representation of subjective value under risk and ambiguity.</a> J. Neurophysiol. 103, 1036-1047 (2010).</li><li>Kahneman, D., Tversky, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Prospect+Theory+-+Analysis+of+Decision+under+Risk.">Prospect Theory - Analysis of Decision under Risk.</a> Econometrica. 47, 263-291 (1979).</li><li>Deichmann, R., Gottfried, J. A., Hutton, C., Turner, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Optimized+EPI+for+fMRI+studies+of+the+orbitofrontal+cortex.">Optimized EPI for fMRI studies of the orbitofrontal cortex.</a> Neuroimage. 19, 430-441 (2003).</li><li>Gilboa, I., Schmeidler, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Maxmin+Expected+Utility+with+Non-Unique+Prior.">Maxmin Expected Utility with Non-Unique Prior.</a> J. Math Econ. 18, 141-153 (1989).</li><li>Hsu, M., Bhatt, M., Adolphs, R., Tranel, D., Camerer, C. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neural+systems+responding+to+degrees+of+uncertainty+in+human+decision-making.">Neural systems responding to degrees of uncertainty in human decision-making.</a> Science. 310, 1680-1683 (2005).</li><li>Boynton, G. A., Engel, S. A., Glover, G., Heeger, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> J Neurosci. 16, 4207-4221 (1996).</li><li>Forman, S. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Improved+Assessment+of+Significant+Activation+in+Functional+Magnetic-Resonance-Imaging+(Fmri)+-+Use+of+a+Cluster-Size+Threshold.">Improved Assessment of Significant Activation in Functional Magnetic-Resonance-Imaging (Fmri) - Use of a Cluster-Size Threshold.</a> Magnetic Resonance in Medicine. 33, 636-647 (1995).</li><li>Genovese, C. R., Lazar, N. A., Nichols, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Thresholding+of+statistical+maps+in+functional+neuroimaging+using+the+false+discovery+rate.">Thresholding of statistical maps in functional neuroimaging using the false discovery rate.</a> NeuroImage. 15, 870-878 (2002).</li><li>Huettel, S. A., Stowe, C. J., Gordon, E. M., Warner, B. T., Platt, M. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neural+signatures+of+economic+preferences+for+risk+and+ambiguity.">Neural signatures of economic preferences for risk and ambiguity.</a> Neuron. 49, 765-775 (2006).</li><li>Smith, V. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Papers in experimental economics. , (1991).</li></ol>

特別な利害関係は宣言されません。

我々は、被験者の動作を特徴付けるとリスクと曖昧に向かって個々の姿勢を推定する実験経済学からのメソッドを使用している。次に、神経データを分析するために、これらの推定値を使用していました。 被験者は、リスクと曖昧さの下の選択肢を作る間、fMRIの活性を調べるための他の方法が8,12前に使用されている。我々のアプローチは、しかし、いくつかの?...

<table border="1"><tbody><tr><td> 名前 </td><td> 会社 </td><td> 注釈 </td></tr><tr><td>アレグラヘッドのみ3.0 T MRI装置</td><td>ジーメンス</td><td>全身スキャナーを使用することもできます</td></tr><tr><td> NM-011の送信ヘッドコイル</td><td>ノバメディカル</td><td></td></tr><tr><td>電子素数</td><td>心理学のソフトウェアツール</td><td>刺激のプレゼンテーションソフト</td></tr><tr><td> MathWorks社のMATLAB </td><td> MathWorks社</td><td></td></tr></tbody></table>

measuring the subjective value of risky and ambiguous options using experimental economics and functional mri methods

我々が行った選択のほとんどは、不確実な結果をもたらす。いくつかのケースでは異なる可能性のある結果の確率は正確には、 &quot;危険&quot;と呼ばれる状態を知られている。確率を推定することができない他のケースでは、これは &quot;あいまい&quot;として記述されている条件である。ほとんどの人がリスクと曖昧さの1,2の両方を嫌っているが、それらの嫌悪の度合いが同じ危険なまたはあいまいなオプションの主観的な値が異なる個体が非常に異なることができるような、個人、全体で大幅に異なります。我々は、実験経済学ベースの方法3で、機能的MRI（fMRI）は危険とあいまいなオプション4の主観的な価値観の神経表現を評価するために組み合わせる。この技術は現在、さまざまな年齢層と異なる患者集団などの異なる集団で、これらの神経表現を研究するために使用することができます。 我々の実験では、被験者は必然の選択肢bを作るその神経活性化がfMRIを用いて追跡している間の2つの選択肢をetween。各試行で被験者は合計金額に、その金額の勝利の確率や勝利に関連付けられた曖昧さのレベルのいずれかで変わる宝くじのどちらかを選択します。私たちのパラメトリック·デザインは、私たちはリスクと曖昧に向かって自分の姿勢を推定するために、各個人の選択行動を使用することができ、したがって、各オプションがそれらのために開催されたことを主観的な値を推定する。デザインのもう一つの重要な特徴は、学習が行われないことができるように、選択された宝くじの結果は実験の間に明らかにされていないことであり、したがって、あいまいなオプションが曖昧とリスク態度が安定している残る。その代わりに、スキャンセッションの終わりに1つまたは少数の試験は無作為に選択されており、実質のお金のために遊んだ。被験者は試験が選択されている事前に知っていないのでそれだけで、それは彼らが支払われている一つの試験であったかのように、彼らはそれぞれ、すべての試験を扱わなければなりません。この設計エン我々は、各被験者には、各オプションの真の主観的な価値を見積もることができることsures。次に、活性化危険なオプションの主観的な値とし、その活性化あいまいなオプションの主観的な値と相関している領域の相関している脳の領域を探します。

Watch this Scientific Journal Video about Measuring the Subjective Value of Risky and Ambiguous Options using Experimental Economics and Functional MRI Methods at JoVE.com

Measuring the Subjective Value of Risky and Ambiguous Options using Experimental Economics and Functional MRI Methods

人間の脳では危険とあいまいなオプションの主観的価値の神経表現を決定するために、機能的MRIや行動の方法を使用して。

実験経済学と機能的MRI法を用いたリスキーかつ曖昧なオプションの主観的な値を測定する

Most of the choices we make have uncertain consequences. In some cases the probabilities for different possible outcomes are precisely known, a condition ...

measuring-subjective-value-risky-ambiguous-options-using-experimental

Research

JoVE Journal

Neuroscience

12.0K ビュー.  Yale School of Medicine. 人間の脳では危険とあいまいなオプションの主観的価値の神経表現を決定するために、機能的MRIや行動の方法を使用して。

ビデオ: Measuring the Subjective Value of Risky and Ambiguous Options using Experimental Economics and Functional MRI Methods

Combining Behavioral Endocrinology and Experimental Economics: Testosterone and Social Decision Making

Behavioral endocrinological research in humans as well as in animals suggests that testosterone plays a key role in social interactions. Studies in rodents have shown a direct link between testosterone and aggressive behavior1 and folk wisdom adapts these findings to humans, suggesting that testosterone induces antisocial, egoistic or even aggressive behavior2. However, many researchers doubt a direct testosterone-aggression link in humans, arguing instead that testosterone is primarily involved in status-related behavior3,4. As a high status can also be achieved by aggressive and antisocial means it can be difficult to distinguish between anti-social and status seeking behavior.
We therefore set up an experimental environment, in which status can only be achieved by prosocial means. In a double-blind and placebo-controlled experiment, we administered a single sublingual dose of 0.5 mg of testosterone (with a hydroxypropyl-&beta;-cyclodextrin carrier) to 121 women and investigated their social interaction behavior in an economic bargaining paradigm. Real monetary incentives are at stake in this paradigm; every player A receives a certain amount of money and has to make an offer to another player B on how to share the money. If B accepts, she gets what was offered and player A keeps the rest. If B refuses the offer, nobody gets anything. A status seeking player A is expected to avoid being rejected by behaving in a prosocial way, i.e. by making higher offers.
The results show that if expectations about the hormone are controlled for, testosterone administration leads to a significant increase in fair bargaining offers compared to placebo. The role of expectations is reflected in the fact that subjects who report that they believe to have received testosterone make lower offers than those who say they believe that they were treated with a placebo. These findings suggest that the experimental economics approach is sensitive for detecting neurobiological effects as subtle as those achieved by administration of hormones. Moreover, the findings point towards the importance of both psychosocial as well as neuroendocrine factors in determining the influence of testosterone on human social behavior.

The procedure described in this protocol shows that testosterone administration and folk beliefs about testosterone may be associated with directly opposed social behaviors.

行動内分泌学と実験経済学を組み合わせること：テストステロンと社会的意思決定

Behavioral endocrinological research in humans as well as in animals suggests that testosterone plays a key role in social interactions. Studies in ...

神経科学

Assessment of Cerebral Lateralization in Children using Functional Transcranial Doppler Ultrasound (fTCD)

There are many unanswered questions about cerebral lateralization. In particular, it remains unclear which aspects of language and nonverbal ability are lateralized, whether there are any disadvantages associated with atypical patterns of cerebral lateralization, and whether cerebral lateralization develops with age. In the past, researchers interested in these questions tended to use handedness as a proxy measure for cerebral lateralization, but this is unsatisfactory because handedness is only a weak and indirect indicator of laterality of cognitive functions1. Other methods, such as fMRI, are expensive for large-scale studies, and not always feasible with children2.
Here we will describe the use of functional transcranial Doppler ultrasound (fTCD) as a cost-effective, non-invasive and reliable method for assessing cerebral lateralization. The procedure involves measuring blood flow in the middle cerebral artery via an ultrasound probe placed just in front of the ear. Our work builds on work by Rune Aaslid, who co-introduced TCD in 1982, and Stefan Knecht, Michael Deppe and their colleagues at the University of M&uuml;nster, who pioneered the use of simultaneous measurements of left- and right middle cerebral artery blood flow, and devised a method of correcting for heart beat activity. This made it possible to see a clear increase in left-sided blood flow during language generation, with lateralization agreeing well with that obtained using other methods3.
The middle cerebral artery has a very wide vascular territory (see Figure 1) and the method does not provide useful information about localization within a hemisphere. Our experience suggests it is particularly sensitive to tasks that involve explicit or implicit speech production. The 'gold standard' task is a word generation task (e.g. think of as many words as you can that begin with the letter 'B') 4, but this is not suitable for young children and others with limited literacy skills. Compared with other brain imaging methods, fTCD is relatively unaffected by movement artefacts from speaking, and so we are able to get a reliable result from tasks that involve describing pictures aloud5,6. Accordingly, we have developed a child-friendly task that involves looking at video-clips that tell a story, and then describing what was seen.

Assessment of Cerebral Lateralization in Children using Functional Transcranial Doppler Ultrasound fTCD

Functional transcranial Doppler sonography (fTCD) is a simple and non-invasive ultrasound technique which can be used to assess the lateralization of cognitive functions, especially language, and is suitable for use with children.

機能性経頭蓋ドップラー超音波を使って子供の脳の側性化の評価（fTCD）

There are many unanswered questions about cerebral lateralization.  In particular, it remains unclear which aspects of language and nonverbal ability are ...

High-resolution Functional Magnetic Resonance Imaging Methods for Human Midbrain

Functional MRI (fMRI) is a widely used tool for non-invasively measuring correlates of human brain activity. However, its use has mostly been focused upon measuring activity on the surface of cerebral cortex rather than in subcortical regions such as midbrain and brainstem. Subcortical fMRI must overcome two challenges: spatial resolution and physiological noise. Here we describe an optimized set of techniques developed to perform high-resolution fMRI in human SC, a structure on the dorsal surface of the midbrain; the methods can also be used to image other brainstem and subcortical structures.
High-resolution (1.2 mm voxels) fMRI of the SC requires a non-conventional approach. The desired spatial sampling is obtained using a multi-shot (interleaved) spiral acquisition1. Since, T2* of SC tissue is longer than in cortex, a correspondingly longer echo time (TE ~ 40 msec) is used to maximize functional contrast. To cover the full extent of the SC, 8-10 slices are obtained. For each session a structural anatomy with the same slice prescription as the fMRI is also obtained, which is used to align the functional data to a high-resolution reference volume.
In a separate session, for each subject, we create a high-resolution (0.7 mm sampling) reference volume using a T1-weighted sequence that gives good tissue contrast. In the reference volume, the midbrain region is segmented using the ITK-SNAP software application2. This segmentation is used to create a 3D surface representation of the midbrain that is both smooth and accurate3. The surface vertices and normals are used to create a map of depth from the midbrain surface within the tissue4.
Functional data is transformed into the coordinate system of the segmented reference volume. Depth associations of the voxels enable the averaging of fMRI time series data within specified depth ranges to improve signal quality. Data is rendered on the 3D surface for visualization.
In our lab we use this technique for measuring topographic maps of visual stimulation and covert and overt visual attention within the SC1. As an example, we demonstrate the topographic representation of polar angle to visual stimulation in SC.

This article describes techniques to perform high-resolution functional magnetic resonance imaging with 1.2 mm sampling in human midbrain and subcortical structures using a 3T scanner. Use of these techniques to resolve topographic maps of visual stimulation in the human superior colliculus (SC) is given as an example.

人間の中脳の高解像度機能的磁気共鳴画像法

Functional MRI (fMRI) is a widely used tool for non-invasively measuring correlates of human brain activity. However, its use has mostly been focused upon ...

Functional Neuroimaging Using Ultrasonic Blood-brain Barrier Disruption and Manganese-enhanced MRI

Although mice are the dominant model system for studying the genetic and molecular underpinnings of neuroscience, functional neuroimaging in mice remains technically challenging. One approach, Activation-Induced Manganese-enhanced MRI (AIM MRI), has been used successfully to map neuronal activity in rodents 1-5. In AIM MRI, Mn2+ acts a calcium analog and accumulates in depolarized neurons 6,7. Because Mn2+ shortens the T1 tissue property, regions of elevated neuronal activity will enhance in MRI. Furthermore, Mn2+ clears slowly from the activated regions; therefore, stimulation can be performed outside the magnet prior to imaging, enabling greater experimental flexibility. However, because Mn2+ does not readily cross the blood-brain barrier (BBB), the need to open the BBB has limited the use of AIM MRI, especially in mice.
One tool for opening the BBB is ultrasound. Though potentially damaging, if ultrasound is administered in combination with gas-filled microbubbles (i.e., ultrasound contrast agents), the acoustic pressure required for BBB opening is considerably lower. This combination of ultrasound and microbubbles can be used to reliably open the BBB without causing tissue damage 8-11.
Here, a method is presented for performing AIM MRI by using microbubbles and ultrasound to open the BBB. After an intravenous injection of perflutren microbubbles, an unfocused pulsed ultrasound beam is applied to the shaved mouse head for 3 minutes. For simplicity, we refer to this technique of BBB Opening with Microbubbles and UltraSound as BOMUS 12. Using BOMUS to open the BBB throughout both cerebral hemispheres, manganese is administered to the whole mouse brain. After experimental stimulation of the lightly sedated mice, AIM MRI is used to map the neuronal response.
To demonstrate this approach, herein BOMUS and AIM MRI are used to map unilateral mechanical stimulation of the vibrissae in lightly sedated mice 13. Because BOMUS can open the BBB throughout both hemispheres, the unstimulated side of the brain is used to control for nonspecific background stimulation. The resultant 3D activation map agrees well with published representations of the vibrissae regions of the barrel field cortex 14. The ultrasonic opening of the BBB is fast, noninvasive, and reversible; and thus this approach is suitable for high-throughput and/or longitudinal studies in awake mice.

A technique is described for broadly opening the blood-brain barrier in the mouse using microbubbles and ultrasound. Using this technique, manganese can be administered to the mouse brain. Because manganese is an MRI contrast agent that accumulates in depolarized neurons, this approach enables imaging of neuronal activity.

超音波血液脳関門の破壊とマンガン増強MRIを用いた脳機能イメージングの試み

Although mice are the dominant model system for studying the genetic and molecular underpinnings of neuroscience, functional neuroimaging in mice remains ...

Optogenetic Functional MRI

The investigation of the functional connectivity of precise neural circuits across the entire intact brain can be achieved through optogenetic functional magnetic resonance imaging (ofMRI), which is a novel technique that combines the relatively high spatial resolution of high-field fMRI with the precision of optogenetic stimulation. Fiber optics that enable delivery of specific wavelengths of light deep into the brain in vivo are implanted into regions of interest in order to specifically stimulate targeted cell types that have been genetically induced to express light-sensitive trans-membrane conductance channels, called opsins. fMRI is used to provide a non-invasive method of determining the brain's global dynamic response to optogenetic stimulation of specific neural circuits through measurement of the blood-oxygen-level-dependent (BOLD) signal, which provides an indirect measurement of neuronal activity. This protocol describes the construction of fiber optic implants, the implantation surgeries, the imaging with photostimulation and the data analysis required to successfully perform ofMRI. In summary, the precise stimulation and whole-brain monitoring ability of ofMRI are crucial factors in making ofMRI a powerful tool for the study of the connectomics of the brain in both healthy and diseased states.

This protocol describes the steps and data analysis required to successfully perform optogenetic functional magnetic resonance imaging (ofMRI). ofMRI is a novel technique that combines high-field fMRI readout with optogenetic stimulation, allowing for cell type-specific mapping of functional neural circuits and their dynamics across the whole living brain.

光遺伝学機能MRI

The investigation of the functional connectivity of precise neural circuits across the entire intact brain can be achieved through optogenetic functional ...

Effects of Transcranial Alternating Current Stimulation on the Primary Motor Cortex by Online Combined Approach with Transcranial Magnetic Stimulation

Transcranial Alternating Current Stimulation (tACS) is a neuromodulatory technique able to act through sinusoidal electrical waveforms in a specific frequency and in turn modulate ongoing cortical oscillatory activity. This neurotool allows the establishment of a causal link between endogenous oscillatory activity and behavior. Most of the tACS studies have shown online effects of tACS. However, little is known about the underlying action mechanisms of this technique because of the AC-induced artifacts on Electroencephalography (EEG) signals. Here we show a unique approach to investigate online physiological frequency-specific effects of tACS of the primary motor cortex (M1) by using single pulse Transcranial Magnetic Stimulation (TMS) to probe cortical excitability changes. In our setup, the TMS coil is placed over the tACS electrode while Motor Evoked Potentials (MEPs) are collected to test the effects of the ongoing M1-tACS. So far, this approach has mainly been used to study the visual and motor systems. However, the current tACS-TMS setup can pave the way for future investigations of cognitive functions. Therefore, we provide a step-by-step manual and video guidelines for the procedure.

Transcranial Alternating Current Stimulation (tACS) allows the modulation of cortical excitability in a frequency-specific fashion. Here we show a unique approach which combines online tACS with single pulse Transcranial Magnetic Stimulation (TMS) in order to "probe" cortical excitability by means of Motor Evoked Potentials.

経頭蓋交流電流刺激オンライン結合による一次運動野の経頭蓋磁気刺激の効果

Transcranial Alternating Current Stimulation (tACS) is a neuromodulatory technique able to act through sinusoidal electrical waveforms in a specific ...

A Simple Approach to Induce Experimental Autoimmune Neuritis in C57BL/6 Mice for Functional and Neuropathological Assessments

Experimental autoimmune neuritis (EAN) is a well-appreciated experimental model of autoimmune peripheral demyelinating diseases. EAN disease is induced by immunizing mice with neurogenic peptides to direct an inflammatory attack toward components of the peripheral nervous system (PNS). Recent advances have enabled the induction of EAN in the relatively resistant C57BL/6 mouse line using myelin protein zero (P0)106-125 or P0180-199 peptides delivered in adjuvant combined with the injection of pertussis toxin. The ability to induce EAN in the C57BL/6 strain allows for the use of the numerous genetic tools that exist on this mouse background, and thus allows the sophisticated study of disease pathogenesis and interrogation of the mechanistic action of novel therapeutics in combination with transgenic approaches. In this study, we demonstrate a simple approach to successfully induce EAN using the P0180-199 peptide in C57BL/6 mice. We also outline a protocol for the assessment of functional deficits that occur in this model, accompanied by an array of neuropathological features. Thus, this model is a powerful experimental model to study the pathogenesis of human peripheral demyelinating neuropathies, and to determine the efficacy of potential therapies that aim to promote myelin repair and protect against nerve damage in autoimmune neuritis.

This report outlines a simple approach to successfully induce experimental autoimmune neuritis (EAN) using the myelin protein zero (P0)180-199 peptide in combination with Freund&#39;s complete adjuvant and pertussis toxin. We present a sophisticated paradigm capable of accurately assessing the extent of functional deficits and neuropathology that occur in this EAN.

機能と神経病理学的評価の c57bl/6 マウスの実験的自己免疫性視神経炎を誘導するための単純なアプローチ

Experimental autoimmune neuritis (EAN) is a well-appreciated experimental model of autoimmune peripheral demyelinating diseases. EAN disease is induced by ...

Role of Diffusion MRI Tractography in Endoscopic Endonasal Skull Base Surgery

Endoscopic endonasal surgery has gained a prominent role in the management of complex skull base tumors. It allows the resection of a large group of benign and malignant lesions through a natural anatomical extra-cranial pathway, represented by the nasal cavities, avoiding brain retraction and neurovascular manipulation. This is reflected by the patients' prompt clinical recovery and the low risk of permanent neurological sequelae, representing the main caveat of conventional skull base surgery. This surgery must be tailored to each specific case, considering its features and relationship with surrounding neural structures, mostly based on preoperative neuroimaging. Advanced MRI techniques, such as tractography, have been rarely adopted in skull base surgery due to technical issues: lengthy and complicated processes to generate reliable reconstructions for inclusion in the neuronavigation system. 
This paper aims to present the protocol implemented in the institution and highlights the synergistic collaboration and teamwork between neurosurgeons and the neuroimaging team (neurologists, neuroradiologists, neuropsychologists, physicists, and bioengineers) with the final goal of selecting the optimal treatment for each patient, improving the surgical results and pursuing the advancement of personalized medicine in this field.

We present a protocol to integrate diffusion MRI tractography in patient work-up to endoscopic endonasal surgery for a skull base tumor. The methods for adopting these neuroimaging studies in the pre- and intra-operative phases are described.

内視鏡内視鏡頭蓋基外科における拡散MRIトラクトグラフィーの役割

Endoscopic endonasal surgery has gained a prominent role in the management of complex skull base tumors. It allows the resection of a large group of ...

Reliable Acquisition of Electroencephalography Data during Simultaneous Electroencephalography and Functional MRI

Simultaneous electroencephalography (EEG) and functional magnetic resonance imaging (fMRI), EEG-fMRI, combines the complementary properties of scalp EEG (good temporal resolution) and fMRI (good spatial resolution) to measure neuronal activity during an electrographic event, through hemodynamic responses known as blood-oxygen-level-dependent (BOLD) changes. It is a non-invasive research tool that is utilized in neuroscience research and is highly beneficial to the clinical community, especially for the management of neurological diseases, provided that proper equipment and protocols are administered during data acquisition. Although recording EEG-fMRI is apparently straightforward, the correct preparation, especially in placing and securing the electrodes, is not only important for safety but is also critical in ensuring the reliability and analyzability of the EEG data obtained. This is also the most experience-demanding part of the preparation. To address these issues, a straightforward protocol that ensures data quality was developed. This article provides a step-by-step guide for acquiring reliable EEG data during EEG-fMRI using this protocol that utilizes readily available medical products. The presented protocol can be adapted to different applications of EEG-fMRI in research and clinical settings, and may be beneficial to both inexperienced and expert operators.

This article provides a straightforward protocol for acquiring good quality electroencephalography (EEG) data during simultaneous EEG and functional magnetic resonance imaging by utilizing readily available medical products.

同時脳波と機能MRIにおける脳波データの確実な取得

Simultaneous electroencephalography (EEG) and functional magnetic resonance imaging (fMRI), EEG-fMRI, combines the complementary properties of scalp EEG ...

Electrophysiological Methods for Measuring Photopigment Levels in Drosophila Photoreceptors

The Drosophila G-protein-coupled photopigment rhodopsin (R) is composed of a protein (opsin) and a chromophore. The activation process of rhodopsin is initiated by photon absorption-inducing isomerization of the chromophore, promoting conformational changes of the opsin and resulting in a second dark-stable photopigment state (metarhodopsin, M). Investigation of this bi-stable photopigment using random mutagenesis requires simple and robust methods for screening mutant flies. Therefore, several methods for measuring reductions in functional photopigment levels have been designed. One such method exploits the charge displacements within the photopigment following photon absorption and the huge amounts of photopigment molecules expressed in the photoreceptors. This electrical signal, named the early receptor potential (or early receptor current), is measured by a variety of electrophysiological methods (e.g., electroretinogram and whole-cell recordings) and is linearly proportional to functional photopigment levels. The advantages of this method are the high signal-to-noise ratio, direct linear measurement of photopigment levels, and independence of phototransduction mechanisms downstream to rhodopsin or metarhodopsin activation. An additional electrophysiological method called prolonged depolarizing afterpotential (PDA) exploits the bi-stability of Drosophila photopigment and the absorption-spectral differences of fly R and M pigment states. The PDA is induced by intense blue light, converting saturating amounts of rhodopsin to metarhodopsin, resulting in the failure of light-response termination for an extended time in darkness, but it can be terminated by metarhodopsin to rhodopsin conversion using intense orange light. Since the PDA is a robust signal that requires massive photopigment conversion, even small defects in the biogenesis of the photopigment lead to readily detected abnormal PDA. Indeed, defective PDA mutants led to the identification of novel signaling proteins important for phototransduction.

Electrophysiological Methods for Measuring Photopigment Levels in Drosophila Photoreceptors

We present a protocol to electrophysiologically characterize bi-stable photopigments: (i) exploiting the charge displacements within the photopigment molecules following photon-absorption and their huge amount in the photoreceptors, and (ii) exploiting the absorption-spectra differences of rhodopsin and metarhodopsin photopigment states. These protocols are useful to screen for mutations affecting bi-stable photopigment systems.&#160;

ショウジョウバエ光受容体の光色素レベルを測定するための電気生理学的方法

The Drosophila G-protein-coupled photopigment rhodopsin (R) is composed of a protein (opsin) and a chromophore. The activation process of rhodopsin is ...