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Search Results: 1 - 10 of 57446 matches for " Marisela Hernández-González "
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EEGcorco: a computer program to simultaneously calculate and statistically analyze EEG coherence and correlation  [PDF]
Miguel Angel Guevara, Marisela Hernández-González, Araceli Sanz-Martin, Claudia Amezcua
Journal of Biomedical Science and Engineering (JBiSE) , 2011, DOI: 10.4236/jbise.2011.412096
Abstract: EEGcorco is a computer program designed to analyze the degree of synchronization between two electroencephalographic signals (EEG) by mean the analysis of correlation and coherence index. The correlation and coherence values permit the quantitative determination of the similarity among EEG signals from homologous areas of the cerebral hemispheres (interhemispheric), and among localized areas within one cerebral hemisphere (intrahemispheric). EEG coherence is a function of frequency; thus it is commonly presented in a spectral manner (coherence values in every frequency of the spectrum), in contrast, the correlation function has been employed mainly to search periodic components of bioelectrical signals, and normally appears as punctual values defined in time, hence it is not common calculate correlation spectra. EEGcorco offers an easy and novel way to calculate correlation spectra by mean the application of the Fast Fourier Transformation (FFT) to digitized EEG signals. Both, correlation and coherence spectra are obtained in both independent frequencies and frequencies grouped in wide bands. Moreover, the program applies parametric statistical analyses to those coherence and correlation spectra also, for each individual frequency and for the frequencies grouped in bands. The program functions on any PC-compatible computer equipped with a Pentium or superior processor and a minimum of 512 Mb of RAM memory (though the higher the capacity the better). The space required on the hard disk depends on the signals to be analyzed, as the output takes the form of files in text format that occupy very little space. The program has been elaborated completely in the Delphi environment for the Windows operating system. The efficacy and versatility of EEGcorco allow it to be easily adapted to different experimental and clinical needs.
EEGbands: A Computer Program to Statistically Analyze Parameters of Electroencephalographic Signals  [PDF]
Miguel Angel Guevara, Araceli Sanz-Martin, Marisela Hernández-González
Journal of Behavioral and Brain Science (JBBS) , 2014, DOI: 10.4236/jbbs.2014.47032
Abstract: The quantitative analysis of electroencephalographic activity (EEG) is a useful tool for the study of changes in brain electrical activity during cognitive and behavioral functions in several experimental conditions. Their recording and analysis are currently carried out primarily through the use of computer programs. This paper presents a computerized program (EEGbands) created for Windows operating systems using the Delphi language, and designed to analyze EEG signals and facilitate their quantitative exploration. EEGbands applies Rapid Fourier Transformation to the EEG signals of one or more groups of subjects to obtain absolute and relative power spectra. It also calculates both interhemispheric and intrahemispheric correlation and coherence spectra and, finally, applies parametrical statistical analysis to these spectral parameters calculated for wide frequency EEG bands. Unlike other programs, EEGbands is simple and inexpensive, and rapidly and precisely generates results files with the corresponding statistical significances. The efficacy and versatility of EEGbands allow it to be easily adapted to different experimental and clinical needs.
Differential Effect of Acute Stress on Visuospatial Working Memory and Sexual Motivation in Male Rats  [PDF]
Marisela Hernández-González, Enrique Hernández-Arteaga, Mayra Linné Almanza-Sepúlveda, Miguel ángel Guevara
Journal of Behavioral and Brain Science (JBBS) , 2015, DOI: 10.4236/jbbs.2015.57023
Abstract: Working memory is an executive function that is highly dependent on the functioning of the prefrontal cortex. Several studies using food or drink as rewards have demonstrated that rats are capable of performing tasks that involve working memory. Sexual behavior is another highly-rewarding, motivated behavior that has proven to be an efficient incentive in classical operant tasks. Considering that both sexual behavior and working memory are sensitive to the effects of stress, the aim of this study was to determine the effect of acute stress on visuospatial working memory during a sexually-motivated task (a nonmatching-to-sample task in a T-maze) in male rats. Thirty-two male Wistar rats were trained in the T-maze using sexual interaction (intromission and ejaculation) as a reinforcer during a 4-day training period (training sessions held every 4th day). On the basis of their performance, the rats were classified as good-learners (n = 12) and bad-learners (n = 20), and on the fifth day, 6 good-learners and 10 bad-learners were subjected to stress using the cold water immersion model (CWI, 15°C) for 15 minutes before they were evaluated in the T-maze. The remaining rats made up the control group (i.e., they performed the task without previous stress). Results showed that acute stress by CWI improved working memory in the bad-learners but did not affect the performance of the good-learners, although in both groups (good- and bad-learners) stress decreased the sexual motivation to perform the task. It is probable that the increased levels of corticosterone in the stress situation could activate glutamatergic transmission in the prefrontal cortex, thus facilitating working memory and, simultaneously, decreasing testosterone levels, which exerts a negative effect on sexual motivation in these male rats.
Basolateral Amygdala Inactivation Reduces Sexual Motivation in Male Rats during Performance of a T-Maze Task with a Sexual Reward  [PDF]
Marisela Hernández-González, Francisco Abelardo Robles Aguirre, Miguel ángel Guevara, Gina Lorena Quirarte, Paulina Haro Magallanes
Journal of Behavioral and Brain Science (JBBS) , 2014, DOI: 10.4236/jbbs.2014.45024
Abstract: This study was aimed to determine the effect of amygdaline inactivation on the sexual motivation of male rats during a T-maze task with a sexual reward. Subjects were chronically implanted with two stainless-steel cannulae that enabled the infusion of tetrodotoxin, a sodium channel blocker, into the left and right basolateral amygdala (BLA). Animals were divided into 3 groups: saline (SS); TTX1 (tetrodotoxin at 2.5 ng); and TTX2 (tetrodotoxin at 5.0 ng). To induce a sexually-motivated state, all male rats were allowed to have an intromission with a receptive female before performing the T-maze task, after which their sexual motivation was evaluated during seven trials in which a receptive female was placed in one goal-box of the T-maze, and a non-receptive one in the other. Subjects were allowed an intromission as a sexual reward whenever they reached the goal-box containing the receptive female, but were returned to the start-box if they did not. At the end of the experiment, copulation until ejaculation was permitted. Both doses of TTX increased the time rats required to cross the maze stem during the final trials. In terms of sexual interaction, the high dose of TTX increased more markedly mount, intromission and ejaculation latencies and the number of mounts and intromissions. Overall, these results indicate that the BLA may play an important role in modulating sexual behavior, particularly in maintaining sexual motivation in successive trials in a T-maze task and during sexual interaction per se.
Alcohol Suppresses the Electroencephalographic Response to Visual Erotic Stimuli in Young Men  [PDF]
Marisela Hernández-González, Araceli Sanz-Martin, Miguel ángel Guevara, Claudia Amezcua-Gutiérrez, Marina Ruiz Díaz
Journal of Behavioral and Brain Science (JBBS) , 2012, DOI: 10.4236/jbbs.2012.23041
Abstract: Although the combination of alcohol and sex is frequently observed in human social interaction, many questions concerning alcohol’s effects on the processing of sexual stimuli and brain functionality remain unanswered. Erotic films eliciting sexual arousal in humans and affect electroencephalographic (EEG) activity. This study examines the effects of alcohol on cortical EEG activity in young men while viewing an erotic film. Heterosexual males participated in an independent alcohol/placebo group protocol. Thirty-five minutes after beverage ingestion, EEGs were recorded at prefrontal, temporal and parietal derivations in three conditions: baseline, and while watching erotic and neutral films. During the observation of erotic films, only the participants who drank the placebo beverage showed a decrease in alpha1 and an increase in the fast frequencies of the prefrontal regions, as well as a decrease in inter-prefrontal synchronization in the alpha and beta bands. Alcohol suppressed the prefrontal EEG changes associated with watching erotic visual stimuli without affect the sexual arousal. EEG data show that alcohol affecting the functioning of the prefrontal cortex, which could interfere with the adequate processing of visual erotic stimuli. These findings may contribute to improving our understanding of the brain mechanisms that underlie alcohol’s effects on the processing of sexual stimuli.
Prefrontal and Accumbal Electric Activity during Auditory Stimulation in Virgin Female Rats: Changes Related to the Estrous Cycle  [PDF]
Marisela Hernández-González, Diego Radberto Chapa García Abascal, Miguel ángel Guevara, Ricardo Alonso Romero Orozco, Mayra Linné Almanza Sepúlveda, Leopoldo Eduardo Flores Mancilla
Journal of Behavioral and Brain Science (JBBS) , 2013, DOI: 10.4236/jbbs.2013.36047
Abstract: The estrous cycle is a physiological process modulated by hormonal changes associated, in turn, with alterations of the attraction or sensitivity with which females perceive different sensory stimuli. Auditory stimuli play an important role in the social interaction of several mammals, including their sexual behavior and the mother-young relationship. Since the prefrontal cortex (PFC) and nucleus accumbens (Acc) had been associated with the processing and assignation of the incentive value of stimuli, this study was designed to analyze whether electroencephalographic (EEG) activity in the PFC and Acc was modified during the two antagonist phases of the estrous cycle (proestrus-estrus and diestrus) when female rats heard sound recordings with different types of cries emitted by other rats. EEGs were recorded in eight female virgin Wistar rats, 80-100 days old, bilaterally implanted in the PFC and Acc during an awake-quiet state, in three conditions: when hearing 1) cries of pups; 2) cries of adult male rats; and, 3) cries of adult female rats. The cries were recorded from pups (2-10 days old) and male and female adult rats after gentle prodding by a human hand. Each auditory stimulus (which included vocalizations up to 22 kHz) was randomly played back through a speaker placed near the female rats. Only upon perceiving the cries of male rats did the females in the proestrus-estrous phase show a lower relative power in the 14-30 Hz band in the Acc and an increased inter-prefrontal correlation in the 8-13 Hz band. It is probable that these EEG changes are associated with the lower activation or non-anxious state that the female rat presents specifically during the proestrus-estrous phase in response to the alarm cries of adult male rats.

EEG Correlations during WCST Performance in Female Adolescents with Sexual Abuse-Related Post-Traumatic Stress Disorder  [PDF]
Lucía Ester Rizo-Martínez, Araceli Sanz-Martin, Miguel ángel Guevara, Marisela Hernández-González, Olga Inozemtseva, Francisco Abelardo Robles-Aguirre
Journal of Behavioral and Brain Science (JBBS) , 2015, DOI: 10.4236/jbbs.2015.57025
Abstract: Child sexual abuse (CSA) survivors can present post-traumatic stress disorder (PTSD) and alterations in EEG activity and cognition. The aim of this study was to evaluate EEG correlations in female adolescents with CSA-related PTSD during performance of the Wisconsin Card-Sorting Test (WSCT). Inter- and intrahemispheric EEG correlations (INTERr and INTRAr) of those subjects were calculated at rest and during performance of WCST. On this task, the PTSD group obtained higher scores than the control group for the number of correct responses and failure to maintain set. In the between-groups comparisons, the PTSD group presented a higher INTERr between frontal areas in the gamma and slow bands, as well as a higher correlation in the delta band at Fp1-F3; however, this group presented a lower INTRAr between Fp1-P3 and Fp2-P4 in the theta and alpha1 bands. In the comparison between conditions, the PTSD group presented an increased correlation during execution of the WCST, mainly in the gamma band, while the control group showed a decrease of INTRAr in the slow bands. Results are discussed with respect to the influence of CSA- related PTSD on the development of cognition and functional connectivity in the brain.
Electroencephalographic Correlates of Sexual Arousal Induced by Sexually-Explicit Reading in Human Females  [PDF]
Miguel Angel Guevara, Carolina Gómez-Navarro, Claudia Amezcua-Gutiérrez, Marisela Hernández-González, Anders ?gmo
Journal of Behavioral and Brain Science (JBBS) , 2018, DOI: 10.4236/jbbs.2018.811037
Abstract: This study explored the cortical functionality in young women while reading a sexually-explicit text. Electroencephalographic activity (EEG) was recorded in heterosexual women while reading either a sexually-explicit text or one with neutral content. Absolute power (AP) and the degree of EEG synchronization among the prefrontal, temporal and parietal cortices were analyzed for the different EEG bands. To evaluate sexual arousal, valence and general activation, Likert-type and Manikin scales were applied. Subjects scored the sexually-explicit text as more pleasurable, and reported greater general activation and sexual arousal than while reading the neutral one. During reading of the sexually-explicit text only, they showed a higher AP in the beta and gamma bands in temporal areas in both hemispheres, and in the theta band in parietal ones, with a lower degree of EEG synchronization between prefronto-temporal areas in the fast bands. Results show that both hemispheres were activated in these sexually-aroused women. The low bilateral synchronization between prefrontal and temporal regions indicates the independent functionality of these cortices, which could be a requirement for inducing and maintaining sexual arousal during reading of sexually-explicit texts in women. These data should broaden our knowledge of the cortical mechanisms that underlie sexual arousal in women.
Neuropsychological and Electrophysiological Evaluation after Rape: A Case Study of a Teenage Girl  [PDF]
Lucía Ester Rizo-Martínez, Miguel ángel Guevara, Luis Francisco Cerdán, Francisco Abelardo Robles-Aguirre, Araceli Sanz-Martin, Marisela Hernández-González
Journal of Behavioral and Brain Science (JBBS) , 2014, DOI: 10.4236/jbbs.2014.46027
Abstract: Although rape is an event with a high incidence worldwide, there is currently no single consensus about both the general effects and the diagnosis and treatment of this. To evaluate the consequences of rape, a teenage girl was evaluated at two moments: a month-and-a-half and then a year-and-a-half after being raped. Clinical measurements, neuropsychological testing and electroencephalographic recording (EEG) were conducted in four conditions: eyes closed, eyes open, and during performance of two tasks: Towers of Hanoi and Wisconsin. Observations showed subsyndromal symptoms of post-traumatic stress on the first evaluation, and close-to-normal scores on the neuropsychological and cognitive tests in both assessments. Decreased cortical EEG synchronization, mainly in the fast frequencies and in almost all conditions, was obtained in the second evaluation. The results obtained in this study may indicate an early development in the brain, which is discussed in light of current literature on this topic.
Ethanol Effects on Cortical EEG Correlation and Sexual Behavior in Male Rats  [PDF]
Miguel Angel Guevara, Marisela Hernández-González, Mayra Linné Almanza-Sepúlveda, Diego Radberto Chapa García Abascal, Pilar Durán, Carolina Sotelo Tapia, Fabricio Luna Torres
Journal of Behavioral and Brain Science (JBBS) , 2014, DOI: 10.4236/jbbs.2014.42012
Abstract: Ethanol affects sexual behavior drastically, as much as its execution as well as its motivation. Ethanol is a central nervous system depressant and the prefrontal cortex (PFC) is one of the cortical areas most sensitive to its effects. This prefrontal area participates in the modulation of the cognitive control, and furthermore, by mean of connections with the parietal cortex (PC) plays an important role in the processing of sexually relevant stimuli. Considering that it has been reported that the ethanol affects the proper functioning of these cortical areas, particularly decreasing the degree of electroencephalographic (EEG) coupling or correlation between them, the aim of this study was to characterize the effect of a low dose of ethanol on EEG correlation, as well determining if this effect is associated with impaired sexual behavior in male rats. Nine male rats unilaterally implanted were simultaneously recorded the EEG from the PFC and PC to calculate the degree of EEG synchronization (correlation, r) between both cortices during the first 40 minutes post administration of 0.75 g/kg of ethanol. At the end of the EEG recording, the males were submitted to copulatory behavior with a receptive female rat. The ethanol administration was associated with a decreased intrahemispheric correlation of the fast bands between PFC and PC, as well as with an increased mount and intromission latency. This data showed that ethanol in moderate doses decreased the coupling degree between cortices. It is likely that this functional disconnection between the PFC and PC after the ethanol administration could be associated with the difficulty in discriminating incentive value of the sexual stimuli so that decreased the sexual motivation but not the performance of the copulatory parameters in the male rat.
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