Armando F Rocha - Academia.edu (original) (raw)

Papers by Armando F Rocha

ABSTRACT: Financial market crises are frequent events that trigger large financial losses that re... more ABSTRACT: Financial market crises are frequent events that trigger large financial losses that represent an important global systemic risk (GSR). GSR forecasting is, therefore, a necessity to avoid the collapse of the global financial system or market. Understanding GSR dynamics is imperative if it is to be forecasted and controlled. Traditional finance theories have developed many tools for risk management that proved to be unreliable in the case of the 2008 Crisis. Recent results on financial decision-making provided by Neurosciences have being used to model the stock market dynamics. This approach is used, here, to model stock price evolution in 20 bourses during the period between January, 3, 2007 and September, 9, 2011. The results of this study show that the market humor, calculated as a function of the conflict associated with the stock benefit and risk evaluations and with the stock volatility, provides an adequate measure of a systematic global systemic risk, and humor thre...

Recent studies on language processing indicate that language cognition is better understood if as... more Recent studies on language processing indicate that language cognition is better understood if assumed to be supported by a distributed intelligent processing system enrolling neurons located all over the cortex, in contrast to reductionism that propose to localize cognitive functions to specific cortical structures. Here, brain activity was recorded using electroencephalogram while volunteers were listening or reading small texts and had to select pictures that translate meaning of these texts. Several techniques for EEG analysis were used to show this distributed character of neuronal enrollment associated with the comprehension of oral and written descriptive texts. Low Resolution Tomography identified the many different sets ( ) of neurons activated in several distinct cortical areas by text understanding. Linear correlation was used to calculate the information provided by each electrode of the 10/20 system about the identified . Principal Component Analysis (PCA) was used to study the temporal and spatial activation of these sources . This analysis evidenced 4 different patterns of covariation that are generated by neurons located at different cortical locations. These results clearly show that the distributed character of language processing is clearly evidenced by combining available EEG technologies.

Literature in finance and neurosciences shows that male and female differ on many relevant issues... more Literature in finance and neurosciences shows that male and female differ on many relevant issues concerning financial decision investment. Here, we studied the EEG activity recorded while volunteers were playing a stock trading game to investigate these gender differences. 20 males and 20 females made 100 trading decisions using a portfolio of 200 shares of 7 different companies. Males and females were equally successful in earning above the market. sLORETA was used to identify sources of EEG recorded 2 seconds before trading decision. Results showed that male and female use different sets of neuron to make equally successful financial decisions.

Present paper investigates brain activity associated with reasoning required to identify necessit... more Present paper investigates brain activity associated with reasoning required to identify necessities for achieving and maintaining desired goals and with motivation to act with such an intention. We used a 12 second video composed by 6 scenes of 2 seconds each shows a sleeping baby and a flying mosquito that may hurt the baby, creating the necessity to kill it and motivating a mother to think about possible ways of killing the mosquito. EEG was recorded while volunteers were seeing this video. We used LORETA analysis to identify the set of neurons enrolled in video analysis and comprehension, and correlation analysis to calculate the amount of information provided by each electrode about these . Principal Component Analysis of covariation was used to disclose how these neurons enroll themselves to solve each necessary task of treat recognition, motivation triggering and analysis of alternative choices of action. This analysis showed that 3 different components brain activity that provide distinct neural signatures for each scene analysis and comprehension and show that motivation is a very complex psychological concept supported by a widely distributed neural processing.

Brazil has introduced a referendum regarding the prohibition of firearm commerce and propaganda a... more Brazil has introduced a referendum regarding the prohibition of firearm commerce and propaganda arguments has invoked socially and personally driven issues in the promotion of voting in favor of and against firearm control, respectively. Here, we used different techniques to study the brain activity associated with a voter’s perception of the truthfulness of these arguments and their influence on voting decisions. Low Resolution Tomography was used to identify the possible different sets of neurons activated in the analysis of the different types of propaganda. Linear correlation was used to calculate the amount information provided by different electrodes about how these sets of neurons enroll themselves to carry out this cognitive analysis. The results clearly showed that vote decision was not influenced by arguments that were introduced by propaganda, which were typically driven by specific social or self-interest motives. However, different neural circuits were identified in the analysis of each type of propaganda argument, independently of the declared vote (for or against the control) intention.

Cognitive Neuroscience ejounal, Sep 2013

Moral and ethics are important issues in human societies. Recently, the development of new techni... more Moral 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 expected losses and is associated with three different patterns of brain activity that are clearly different for accepting or rejecting the proposed dilemma solution what may explain the neurodynamic differences in solving personal vs impersonal dilemma observed in the present investigation and also described in the literature.

Cognitive Neurosciences ejournal, Nov 2013

Moral dilemma judgment has been extensively studied by neurosciences and much is now known about ... more 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 results seem to validate the theoretical model described in this paper. EEG results shows that dilemma solution requires a complex enrollment of neurons in different parts of the brain in order to assess the benefits and risks of proposed solutions. Finally, the probability of each possible dilemma solution is shown to be adequately calculated from the proposed model

J. Brain Behavioral Sciences, Dec 24, 2013

Background Recent neuroscience investigations on moral judgment have provided useful information... more Background
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.
Methods
Here, we reinvestigate previously fMRI study of personal (PD) and impersonal (ID) moral dilemma judgment, taking profit of these new EEG analysis improvements. Results
PCA analysis disclosed three different patterns of brain activity associated with Dilemma judgment. These patterns are proposed to disclose the neural circuits involved in benefit and risk evaluation; calculating intention to act and controlling decision-making. Regression analysis showed that activity at some cortical areas favor action implementation by increasing intention to act, while activity at some other areas oppose it by decreasing intention to act.
Comparison with Existing Methods
Compared to the previous fMRI results, Loreta and PCA revealed a much greater number of cortical areas involved in dilemma judgment, whose temporal and spatial distribution were different for ID compared to PD.
The present paper suggests that whenever final temporal details of the decision making process is desired, EEG becomes the tool of choice as compared with fMRI.
Conclusions
The presented results are discussed from the utilitarian point of view that proposes adequacy of human action being dependent upon how much pleasure and fear/pain they are associated.

Progress in Neurobiology

Research on Blindsight, Neglect/Extinction and Phantom limb syndromes, as well as electrical meas... more Research on Blindsight, Neglect/Extinction and Phantom limb syndromes, as well as electrical measurements of mammalian brain activity, have suggested the dependence of vivid perception on both incoming sensory information at primary sensory cortex and reentrant information from associative cortex. Coherence between incoming and reentrant signals seems to be a necessary condition for (conscious) perception. General reticular activating system and local electrical synchronization are some of the tools used by the brain to establish coarse coherence at the sensory cortex, upon which biochemical processes are coordinated. Besides electrical synchrony and chemical modulation at the synapse, a central mechanism supporting such a coherence is the N-methyl-d-aspartate channel, working as a ‘coincidence detector’ for an incoming signal causing the depolarization necessary to remove Mg2+, and reentrant information releasing the glutamate that finally prompts Ca2+ entry. We propose that a signal transduction pathway activated by Ca2+ entry into cortical neurons is in charge of triggering a quantum computational process that accelerates inter-neuronal communication, thus solving systemic conflict and supporting the unity of consciousness.

Pediatric Neurology

Reasoning is the result of the computations made by intelligent systems, for instance those in th... more Reasoning is the result of the computations made by intelligent systems, for instance those in the brain. It is not an abstract concept because calculations performed by computations are very concrete transactions among the different central processing unit components. Entropy measurements are proposed here to disclose the plasticity of the cerebral processing associated with language comprehension in video game playing. It is also assumed that entropy may be evaluated from the correlation coefficients obtained for the game event-related activity calculated for the different electroencephalogram derivations in the 10/20 system. The brain mapping derived from these entropy measurements clearly demonstrates the reallocation of speech functions to right brain areas when the classic left language circuits are damaged during prenatal life.

Medical Hypothesis

The electrical membrane properties have been the key issues in the understanding of the cerebral ... more The electrical membrane properties have been the key issues in the understanding of the cerebral physiology for more than almost two centuries. But, molecular neurobiology has now discovered that biochemical transactions play an important role in neuronal computations. Quantum computing (QC) is becoming a reality both from the theoretical point of view as well as from practical applications. Quantum mechanics is the most accurate description at atomic level and it lies behind all chemistry that provides the basis for biology ... maybe the magic of entanglement is also crucial for life. The purpose of the present paper is to discuss the dendrite spine as a quantum computing device, taking into account what is known about the physiology of the glutamate receptors and the cascade of biochemical transactions triggered by the glutamate binding to these receptors.

Cognitive Brain Research

Despite the increasing number of experimental mapping showing that human arithmetic cognition is ... more Despite the increasing number of experimental mapping showing that human arithmetic cognition is supported by widely spread neural circuits; the theoretical reasoning about these data remains mostly metaphorical and guided by a connectionist approach. Although neurons at distinct areas in the brain are assumed to take charge of different duties in the solution of the experimental task, the results are always discussed by hypothesizing some association between the different areas without questioning any difference of behavior at the level of the neurons at each of these areas. Here, the brain is assumed as Distributed Intelligent Processing System (DIPS) formed by collections of loosely interacting specialized agents (neurons), each agent specializing, for example, in data collection (sensors), problem solving (associative neurons), data communication (interneuronal systems) and in acting upon the surrounding environment (motorneurons). A new technique for EEG brain mapping is proposed and used to study arithmetic cognition in elementary school aged children and adults. Factor analysis showed three distinct patterns of neuronal recruitment for arithmetic calculations in all experimental groups which varied according to the type of calculation, age and sex.

The relationship between education and cognitive neuroscience is an old issue from which the idea... more The relationship between education and cognitive neuroscience is an old issue from which the idea of the ‘neuroeducators’ was proposed 25 years ago. The premise of this idea is that the knowledge about how the brain operates our learning could help teachers in the classrootm. Despite of being an old issue, there are yet some unsolved matters. Firstly, how neuroscience and education could integrate biological understanding about learning cerebral process has not been yet clearly discussed. The present paper presents the results from Enscer–Teaching the Brain Project – that has been developed in Brazil for five years. During that time educators attended to neuroscience courses conducted by researches involved in the project, and were taught about brain learning mechanisms, language and arithmetic neural circuits and how this knowledge may be used for teaching the brain. On the other side neuroscientists were informed by educators about social and cultural demands for optimized learning. Good results came from this mutual relationship making us to believe that neuroeducation is atwo-way traffic.

Human cognition in evolution & development ejournal

The neural efficiency hypothesis (NEH) of intelligence claims that subjects performing a complex ... more 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 of information provided by each electrode about task solution. This analysis also shows that normal children allocate an amount of computational resources greater than that allocated by mental retarded children to solve both reading and calculation task. Most important, it is shown that what means that mental retarded children allocate less and normal children allocate more computational resources than the task uncertainty . This shows that neural efficiency is bound by task uncertainty, such that intelligence increases as approaches 1 and decreases otherwise. Although the different genders were shown to use different neural circuits to solve the same task, these differences are equally effective and did not resulted in IQ differences.

Marketing Science ejournal

The interest of marketing science in using neuroscience techniques to understand the consumer’s t... more The interest of marketing science in using neuroscience techniques to understand the consumer’s thought processes, dates back to the 1970s, when EEG data were recorded while subjects were watching TV commercials. Recently, fMRI was used to study the neural correlates of culturally based brands and neural predictors of purchases. These studies have discovered important properties of the neural circuits that are associated with consumer decision-making process and satisfaction. Here, EEG brain mapping was used to study the dynamics of the brain activity associated with these processes. The present study validated the EEG technology as an adequate neuromarketing tool and shows that consumer’s satisfaction evaluation with the aesthetical dermatological treatment involved the activation of neural circuits involved with facial beauty evaluation.

Metaphysics ejournal

There is still a controversy if human volitions and actions are governed by causal laws or obeys ... more There is still a controversy if human volitions and actions are governed by causal laws or obeys free will. Neurosciences start to study the neural correlates of free will by investigating how brains make decisions. Here, some of questions about free will are discussed from the neurosciences point of view taking into consideration a neuroeconomic model of decision making. This model is used here with the purpose of providing very formal definitions of key concepts raised in any free will discussion such as goals, necessity, motivation, etc., and to provide a formal background for discussing decision making. One of the conclusions of this discussion is that free will is computable but unpredictable, therefore not submitted to causal laws. In addition, the electroencephalogram was recorded in an experiment about choice selection of alternative actions and it presented here as an example of how neurosciences may study the neural correlates of free will.

Cognitive Neuroscience ejournal

Arguments for and against gun control are polarized at two opposite ends of a broad spectrum: per... more Arguments for and against gun control are polarized at two opposite ends of a broad spectrum: personal liberties and social benefits. Brazil has introduced a referendum regarding the prohibition of firearm commerce and propaganda arguments, similar to the present ongoing discussion in the U.S. It has invoked socially and personally driven issues in the promotion of voting in favor of and against firearm control, respectively. Here, we used electroencephalography (EEG) technology to study the brain activity associated with a voter’s perception one week prior to Election Day, of the truthfulness of these arguments and their influence on voting decisions. The present results clearly showed that this decision was not influenced by arguments that were introduced by propaganda, which were typically driven by specific social and self-interest motives. In addition, different neural circuits were identified in the analysis of arguments for and against gun control.

Neuroeconomics ejounal

Efficiency Market hypothesis assume that all investors reason in the same way to make their finan... more Efficiency Market hypothesis assume that all investors reason in the same way to make their financial decisions. In contrast, Neurosciences have provided strong evidences that cognitive diversity is the hallmark of human intelligence. Neurofinances has shown that volunteers learned different profitable financial decision-making strategies depending on the kind of market they begun to trade. Here, we decide to further explore this hypothesis by studying a possible correlation between brain activity and the financial variables in a stock market game and to test if this correlation differ between experimental groups that trade in different market conditions. Present results show that volunteers had different perceptions of the studied financial variables depending if they initially traded in a bear or a bull market. Our findings are consistent with the hypothesis that different neural circuits were learned to monitor the different financial variables studied here, depending on market conditions.

Financial Crisis ejournal

Financial market crises are frequent events that trigger large financial losses and represent imp... more Financial market crises are frequent events that trigger large financial losses and represent important global systemic risk (GSR). GSR forecasting is, therefore, a necessity to avoid the collapse of the global financial market. Understanding GSR dynamics is imperative if GSR is to be forecasted and controlled. Traditional finance theories have developed many tools for risk management that proved to be unreliable in the case of the 2008 Crisis. Recent results on financial decision-making provided by Neurosciences have being used to model the stock market dynamics. This approach is used, here, to model stock price evolution in 20 bourses during the period between January, 3, 2007 and September, 9, 2011. Present results show that: a) the market humor, calculated as a function of the conflict associated with the stock benefit and risk evaluations and with the stock volatility, provides an adequate measure of a systematic global systemic risk, and b) humor threshold variation reflect unsystematic global systemic risks.