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Full-Text Articles in Neuroscience and Neurobiology

Characterizing Tissue Fate After Transient Cerebral Ischemia Of Varying Duration Using Quantitative Diffusion And Perfusion Imaging, Juergen Bardutzky, Qiang Shen, Nils Henninger, Stefan Schwab, Timothy Duong, Marc Fisher Apr 2015

Characterizing Tissue Fate After Transient Cerebral Ischemia Of Varying Duration Using Quantitative Diffusion And Perfusion Imaging, Juergen Bardutzky, Qiang Shen, Nils Henninger, Stefan Schwab, Timothy Duong, Marc Fisher

Nils Henninger

BACKGROUND AND PURPOSE: The purpose of this study was to investigate the effects of reperfusion on ischemic lesion evolution and pixel-by-pixel apparent diffusion coefficient-cerebral blood flow (ADC-CBF) dynamics of core and mismatch tissues after 35, 60, and 95 minutes of transient focal ischemia in rats (n=28). METHODS: Serial diffusion-, perfusion-, and T2-weighted imaging were performed up to 24 hours. The evolution of the magnetic resonance image-derived lesion volume was investigated and ADC-CBF scatterplots were performed to prospectively characterize the ADC and CBF dynamics of core and mismatch tissues with different fates. For comparison, similar analysis was performed on a historical …


Differential Recovery Of Multimodal Mri And Behavior After Transient Focal Cerebral Ischemia In Rats, Kenneth Sicard, Nils Henninger, Marc Fisher, Timothy Duong, Craig Ferris Apr 2015

Differential Recovery Of Multimodal Mri And Behavior After Transient Focal Cerebral Ischemia In Rats, Kenneth Sicard, Nils Henninger, Marc Fisher, Timothy Duong, Craig Ferris

Nils Henninger

The association between recovery of brain function and behavior after transient cerebral ischemia in animals and humans is incompletely characterized. Quantitative diffusion- (DWI), perfusion- (PWI), T(2)-weighted (T(2)WI), and functional magnetic resonance imaging (fMRI) were performed before, during, and up to 1 day after 20-mins transient middle cerebral artery occlusion (tMCAO; n=6) or sham operation (n=6) in male Sprague-Dawley rats. Viability thresholds were employed to calculate diffusion, perfusion, and T(2) lesion volumes. Region of interest analysis was used to evaluate structural and functional MR signal changes within the sensorimotor network, which were then related to corresponding behavioral measures. Post-mortem 2,3,5-triphenyltetrazolium chloride …


Moral Dilemma Judgment Revisited: A Loreta Analysis, Armando F. Rocha, Fábiot T. Rocha, Eduardo Massad Oct 2013

Moral Dilemma Judgment Revisited: A Loreta Analysis, Armando F. Rocha, Fábiot T. Rocha, Eduardo Massad

Armando F Rocha

Recent neuroscience investigations on moral judgment have provided useful information about how brain processes such complex decision making. All these studies so were fMRI investigations and therefore constrained by the poor resolution of this technique. Recent advances in electroencephalography (EEG) analysis provided by Low Resolution Tomogray (Loreta), Principal Component (PCA), Correlation and Regression Analysis improved EEG spatial resolution and make EEG a very useful technique in decision-making studies. Here, we reinvestigate previously fMRI study of personal (PD) and impersonal (ID) moral dilemma judgment, taking profit of these new EEG analysis improvements. Compared to the previous fMRI results, Loreta and PCA …


Brain Activity Of Normal And Low Iq Children: The Neural Efficiency Hypothesi, Fabio T. Rocha, Armando F. Rocha, Sueli Angeloti Dec 2012

Brain Activity Of Normal And Low Iq Children: The Neural Efficiency Hypothesi, Fabio T. Rocha, Armando F. Rocha, Sueli Angeloti

Armando F Rocha

The neural efficiency hypothesis (NEH) of intelligence claims that subjects performing a complex task may well use a limited number of brain circuits and/or fewer neurons while poor performers use more circuits and/or neurons, some of which are inessential or detrimental to task performance. The present paper studies the EEG activity associated with reading and arithmetic calculation by normal and mental retarded children. Correlation analysis of the electrical activity recorded by 10/20 electrode system was used to calculate the amount of information allocated by individuals to solve these tasks. Multiple regression analyses showed that IQ linearly correlates with the amount …


Moral Dilemma Judgment: A Neuroeconomic Approach, Armando F. Rocha, Fábio T. Rocha, Eduardo Massad Dec 2012

Moral Dilemma Judgment: A Neuroeconomic Approach, Armando F. Rocha, Fábio T. Rocha, Eduardo Massad

Armando F Rocha

Morals and ethics are important issues in human societies. Recently, the development of new techniques for studying the human brain has brought moral and ethical discussions to the realm of neuroscience investigations. Controversies still remain regarding the results of studies about morals and ethics and the understanding of the neurodynamics of dilemma judgment, which seems to depend on the nature of the studied dilemma (e.g., personal versus impersonal). Here, we proposed to understand the differences between personal and impersonal dilemmas in the context of losses modeled by neuroeconomic theory. The results show that the dilemma solution correlates nicely with the …


Modeling Moral Dilemma Judgment, Armando F. Rocha, Fábio T. Rocha, Eduardo Massad Dec 2012

Modeling Moral Dilemma Judgment, Armando F. Rocha, Fábio T. Rocha, Eduardo Massad

Armando F Rocha

Moral dilemma judgment has been extensively studied by neurosciences and much is now known about the cerebral dynamics supporting this kind of reasoning. Neuroeconomics has provided some interesting hypothesis for modeling decision making. The present paper aims to test if dilemma judgment may be formalized by this kind of modeling. In addition, fMRI and electroencephalographic (EEG) studies have shown that dilemma judgment involves benefit and risk analysis supported by specific neural systems. Because of this, the EEG was recorded while volunteers were judging moral dilemma in order to provide additional information to test the proposed hypothesis. Present experimental and simulated …