RESUMO
AIM: It is established that intravesical sodium hyaluronate and chondroitin sulfate has high efficacy in patients with bladder pain syndrome/interstitial cystitis (BPS/IC). Currently, an oral form of chondroitin sulfate is also available. The aim of study was to compare the efficacy of intravesical hyaluronic acid monotherapy and long-term oral chondroitin sulfate in combination with intravesical therapy in patients with BPS/IC. MATERIALS AND METHODS: A total of 59 patients with BPS/IC were randomized in two groups. In Group 1, 30 women (mean age 57.1 years) received viscoelastic solution of sodium hyaluronate 50 ml 1 time per week for 12 weeks as intravesical monotherapy. In Group 2 (n=29), patients were prescribed to complex therapy, which included the similar intravesical therapy combined with chondroitin sulfate in a dose 0.39 g, 2 capsules 3 times a day, also for 12 weeks. All patients completed visual analogue scale (VAS), interstitial cystitis symptom index (ISCI), interstitial cystitis problems index (ICPI) and voiding diary before and 1 week after the start of therapy. In all cases a cystoscopy and urodynamic study were performed in order to exclude other bladder pathologies. RESULTS: At baseline, a mean VAS score in both groups was 7 points, a mean ISCI score was 17 points in Group 1 and 18 points in Group 2 (p>0.1). The mean ICPI score in both groups was 15 points. A frequency of urination in Group 1 and 2 was 11.4 and 11.6 per day, respectively (p>0,1). A mean volume of urination was 138+/-24.6 and 131+/-18.6 , respectively. After 12 weeks of therapy there was significant improvement of VAS, ICSI and ICPI scores in both groups, as well as frequency and volume of urination, but in Group 2 an improvement in almost all parameters studied, except for the volume of urination, was more pronounced. CONCLUSION: The combined therapy of BPS/IC with intravesical hyaluronic acid and oral chondroitin sulfate provides significantly better results in comparison with intravesical hyaluronic acid as monotherapy.
Assuntos
Sulfatos de Condroitina , Cistite Intersticial , Ácido Hialurônico , Dor , Administração Intravesical , Sulfatos de Condroitina/uso terapêutico , Cistite Intersticial/complicações , Cistite Intersticial/tratamento farmacológico , Feminino , Humanos , Ácido Hialurônico/uso terapêutico , Pessoa de Meia-Idade , Dor/tratamento farmacológico , Medição da DorRESUMO
This work is focused on the effect of the electrode/electrolyte interface restructuring under the variation of carbon surface topography, as one of the possible factors determining the electrochemical activity of different carbon materials in Li-air batteries. Molecular dynamics simulation was used to investigate an acetonitrile-based electrolyte in contact with the following carbon surfaces: graphene plane, single-layer graphene edge, and multi-layer graphene edge. It was shown that the surface topography strongly influences the electrolyte structure at the interface. Acetonitrile has a layered structure at the plane and the edge of graphene nanoribbons and a qualitatively different chessboard structure at the multi-layer graphene edge. It was found from the potentials of mean force that the variation of the surface topography induces the redistribution of the reactants Li+ and O2 near the surface and influences their adsorption rate. This should affect the kinetics of the oxygen reduction reaction and may explain massive deposition of discharge products on graphene edges in Li-air batteries.
RESUMO
Attentional biases towards affective stimuli reflect an individual balance of appetitive and aversive motivational systems. Vigilance in relation to threatening information reflects emotional imbalance, associated with affective and somatic problems. It is known that meditation practice significantly improves control of attention, which is considered to be a tool for adaptive emotional regulation. In this regard, the main aim of the present study was to evaluate the influence of meditation on attentional bias towards neutral and emotional facial expressions. Eyes were tracked while 21 healthy controls and 23 experienced meditators (all males) viewed displays consisting of four facial expressions (neutral, angry, fearful and happy) for 10 s. Measures of biases in initial orienting and maintenance of attention were assessed. No effects were found for initial orienting biases. Meditators spent significantly less time viewing angry and fearful faces than control subjects. Furthermore, meditators selectively attended to happy faces whereas control subjects showed attentional biases towards both angry and happy faces. In sum we can conclude that long-term meditation practice adaptively affects attentional biases towards motivationally significant stimuli and that these biases reflect positive mood and predominance of appetitive motivation.
Assuntos
Atenção/fisiologia , Emoções , Movimentos Oculares/fisiologia , Expressão Facial , Meditação/psicologia , Adulto , Humanos , MasculinoRESUMO
The main aim was to study effects of long-term meditation practice on event-related brain potentials (ERPs) during affective picture viewing. The meditators' (N = 20), contrary to control (N = 20), did not demonstrate arousal-related increases in the mid-latency (200-400 ms) ERP positivity over the right hemisphere. We also found in the same time window stronger ERP negativity for meditators over central regions, regardless of picture valence. We assume that long-term meditation practice enhances frontal top-down control over fast automatic detection of stimulus salience.
Assuntos
Cérebro/fisiologia , Potenciais Evocados/fisiologia , Meditação/psicologia , Reconhecimento Visual de Modelos/fisiologia , Adulto , Tonsila do Cerebelo/fisiologia , Nível de Alerta , Mapeamento Encefálico , Eletroencefalografia , Emoções/fisiologia , Humanos , Masculino , Estimulação LuminosaRESUMO
The influence of citicoline, phenylpiracetam, pentoxifylline and N-phenylacetyl-L-prolylglycine on cognitive processes and functional state of mitochondria in the neocortex of alloxan-diabetic rats has been studied. The drug effects on cognitive processes were assessed using passive avoidance tests in the dark-light camera. Latent period and the number of animals with amnesia skill on 6th and 20th days of drug administration were recorded. Functional status of mitochondria was assessed by mitochondrial pore opening and mitochondrial transmembrane potential (Y) on 20th day. It has been established that course administration of phenylpiracetam, citicoline and to a lesser extent N-phenylacetyl-L-prolylglycine, but not pentoxifylline, improves the processes of learning and storing conditional skill. At the same time, the nootropic activity of studied drugs was comparable to their effect on the functional state of mitochondria in neocortical neurons in rats with chronic hyperglycemia. According to mitoprotective activity (prevention of opening of mitochondrial cyclosporin-A-sensitive pores and restoration of mitochondrial transmembrane potential), the maximum potential was observed for citicoline and phenylpiracetam, and the minimum--for pentoxifylline. The results point out the importance of mitoprotective properties in nootropic effects of studied drugs.
Assuntos
Córtex Cerebral/efeitos dos fármacos , Citidina Difosfato Colina/farmacologia , Dipeptídeos/farmacologia , Mitocôndrias/efeitos dos fármacos , Nootrópicos/farmacologia , Pentoxifilina/farmacologia , Piracetam/análogos & derivados , Aloxano , Amnésia/complicações , Amnésia/tratamento farmacológico , Amnésia/fisiopatologia , Animais , Aprendizagem da Esquiva/efeitos dos fármacos , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Cognição/efeitos dos fármacos , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/fisiopatologia , Hiperglicemia/complicações , Hiperglicemia/tratamento farmacológico , Hiperglicemia/fisiopatologia , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Proteínas de Transporte da Membrana Mitocondrial/agonistas , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Poro de Transição de Permeabilidade Mitocondrial , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Piracetam/farmacologia , Ratos , Ratos WistarRESUMO
In patients with newly diagnosed untreated grade I-II hypertension, EEG oscillations were recorded under conditions activation of the two basic motivational systems, defensive motivational system and positive reinforcement system, evoked by recall of personally meaningful emotional events. The 64-channel EEG and cardiovascular reactivity (beat-by-beat technology) were simultaneously recorded. At rest, hypertensive patients had significantly reduced platelet serotonin concentrations in comparison with healthy individuals. The patients experiencing emotional activation were characterized by significantly lower intensity of positive emotions associated with more pronounced suppression of EEG activity in the delta (2-4 Hz) and theta (ranges of frequency 4-6 and 6-8 Hz) oscillators in the parieto-occipital cortex (zones P and PO) in both hemispheres of the brain. The findings attest to insufficient function of the brain serotonin system and hypoactivation of the reward/reinforcement system in patients with primary hypertension.
Assuntos
Ritmo Delta , Hipertensão/fisiopatologia , Motivação/fisiologia , Recompensa , Ritmo Teta , Adulto , Plaquetas/química , Plaquetas/metabolismo , Mapeamento Encefálico , Estudos de Casos e Controles , Emoções/fisiologia , Humanos , Hipertensão/diagnóstico , Hipertensão/metabolismo , Masculino , Rememoração Mental/fisiologia , Pessoa de Meia-Idade , Lobo Occipital/fisiopatologia , Lobo Parietal/fisiopatologia , Serotonina/metabolismo , Índice de Gravidade de DoençaRESUMO
AIM: To investigate cardiovascular stress-reactivity in association with individual preconscious affective biases to threatening and appetitive facial stimuli. PATIENTS AND METHODS: Preconscious affective biases were assessed in healthy individuals (n = 38, mean age 28, 10 years, 1SD = 8.64) using a modified (masked) version of a pictorial emotional Stroop task (backward masking of the angry, fearful and joyful faces). RESULTS: It was revealed that individual preconscious bias to speeded up perception of angry faces correlates significantly with heightened anxiety, lowered platelet serotonin (5-HT) levels, sustained central overactivation of at rest (as indexed by lowered delta, theta, and beta-1 EEG power over frontal, central and posterior cortical areas) and exaggerated arterial blood pressure stress-reactivity during re-experiencing of personally relevant anger. CONCLUSIONS: considering uncovered associations, individuals with preconscious bias to speeded up perception of angry faces may be regarded as having enhanced risk to fall sick with essential hypertension, yet this perceptive bias could be seen as a putative neurobehavioral predictor of the risk.
Assuntos
Doenças Cardiovasculares/psicologia , Emoções/fisiologia , Nervo Facial , Mascaramento Perceptivo/fisiologia , Estresse Psicológico/psicologia , Adulto , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/fisiopatologia , Estimulação Elétrica , Eletroencefalografia , Seguimentos , Humanos , Masculino , Prognóstico , Valores de Referência , Estresse Psicológico/complicaçõesRESUMO
Toxicological pharmacological study of the molecular complex of nifedipine and glycyrrhizic acid 1:10 (glycidipine) obtained using mechanochemical technique was carried out. High hypotensive and cardioprotective effects of the agent were demonstrated. Chronic administration (45 days) produced no toxic effects in vital organs and systems of Wistar rats and ISIAH rats.
Assuntos
Anti-Hipertensivos/administração & dosagem , Cardiotônicos/administração & dosagem , Ácido Glicirrízico/administração & dosagem , Nifedipino/administração & dosagem , Animais , Antiarrítmicos/farmacologia , Anti-Hipertensivos/química , Anti-Hipertensivos/toxicidade , Cardiotônicos/química , Cardiotônicos/toxicidade , Combinação de Medicamentos , Avaliação Pré-Clínica de Medicamentos , Metabolismo Energético/efeitos dos fármacos , Feminino , Ácido Glicirrízico/química , Ácido Glicirrízico/toxicidade , Hipertensão/tratamento farmacológico , Masculino , Isquemia Miocárdica/induzido quimicamente , Isquemia Miocárdica/tratamento farmacológico , Nifedipino/química , Nifedipino/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar , Solubilidade , Verapamil/farmacologiaRESUMO
Transurethral stenting of the ureter was made in 130 patients (51 males and 79 females, aged 19-81, mean age 51.3 years) after contact ureterolithotripsy (n=86), endoureterotomy (n=13) and endopyelotomy (n=31). All the patients received internal polyuretanic stents (size N 6 F) made by one company. The patients were randomized into two groups by the shape of the stent. Group 1 (n=65) received a modified mono-pigtail stent made of the standard polyuretanic double-pigtail stent by cutting off 2-4 cm of the distal end and distal (vesical) curl. In group 2 (n=65) stenting was made with standard double-pigtail stent. Questionnaire survey was made 2 weeks after stenting, 1 month before stent removal and 1.5 months after stent removal. In the postoperative period 12 patients of group 2 (18.5%) developed acute pyelonephritis resultant from vesicorenal reflux. In other cases pyelonephritis was managed by draining bladder with urethral catheter. In group 1 vesicoureteral reflux was absent, but in 3 cases (4.6%) there was an attack of acute pyelonephritis because of obstruction of the intramural (not intubated by the stent) part of the ureter with fragments of the crushed concrement. This attack required urgent ureterolithoextraction and removal of the stent in 2 cases, transcutaneous nephrostomy in 1 case. Mean postoperative stay in the hospital was 3.1 +/- 0.6 in group 1 and 6.7 +/- 1.2 (p = 0.001) days in group 2. The comparison of the stent-related symptoms 2 weeks after stenting and before stent removal showed that severity of the symptoms was significantly greater in group 2 vs group 1 (21.3 and 9.6, respectively). Thus, the proposed mono-pigtail stent reduces severity of stent-related symptoms 2.5 times and improves quality of life. Further prospective studies are planned for final assessment of efficacy of the modified stents and their influence on quality of life.
Assuntos
Qualidade de Vida , Stents , Inquéritos e Questionários , Ureter/cirurgia , Doença Aguda , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/terapia , Pielonefrite/etiologia , Pielonefrite/terapia , Refluxo Vesicoureteral/etiologia , Refluxo Vesicoureteral/terapia , Adulto JovemRESUMO
Chronic administration of cerebrocurin and cerebrolysin to Mongolian jirds with acute cerebral stroke model led to a decrease in the mitochondrial dysfunction on the 4th day, which was manifested by their ability to inhibit the mitochondrial permeability transition pore opening, normalize the energy metabolism, and enhance c-fos gene expression. In addition, cerebrocurin restored the morphofunctional state of neurons and favored the cell loss mechanism switching from necrosis to apoptosis. With respect to all characteristics under consideration, the effect of cerebrocurin exceeded with statistical confidence that of cerebrolysin.
Assuntos
Neuropeptídeos/uso terapêutico , Fármacos Neuroprotetores/uso terapêutico , Acidente Vascular Cerebral/prevenção & controle , Doença Aguda , Aminoácidos/uso terapêutico , Animais , Apoptose , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Misturas Complexas , Metabolismo Energético/efeitos dos fármacos , Gerbillinae , Mitocôndrias/fisiologia , Necrose , Neurônios/efeitos dos fármacos , Neurônios/patologia , Proteínas Proto-Oncogênicas c-fos/metabolismo , Acidente Vascular Cerebral/metabolismo , Acidente Vascular Cerebral/patologiaRESUMO
The aim of the present work was to identify possible associations between individual balances in the activity of the positive and negative reinforcement motivation systems using a method based on emotional modulation of the startle reaction (EMSR) by motivationally significant emotionally positive and negative contextual visual stimuli and measures of cardiovascular system activity. Studies were performed using healthy males (mean age 30.29 +/- 9.8 years) with normal and first-episode excessive increases in arterial blood pressure (systolic blood pressure to greater than 140 mmHg, diastolic to greater than 90 mmHg). Cluster analysis of EMSR data identified groups of individuals with different activity profiles for the positive and negative reinforcement systems. Groups of subjects with changes in the balance of activity towards a lower level of positive reinforcement system activity (smaller startle reflexes to positive contextual stimuli) or a higher level of negative reinforcement system activity (larger startle reactions to threatening contextual stimuli) showed significantly greater baseline SBP and DBP. The possible mechanisms of the modulatory influences of the balance of system activities on autonomic vascular regulatory processes are discussed.
Assuntos
Pressão Sanguínea/fisiologia , Emoções/fisiologia , Motivação , Reflexo de Sobressalto/fisiologia , Adulto , Eletromiografia , Resposta Galvânica da Pele/fisiologia , Frequência Cardíaca/fisiologia , Hemodinâmica/fisiologia , Humanos , Masculino , Contração Muscular/fisiologia , Músculos Oculomotores/fisiologia , Estimulação Luminosa , Reforço Psicológico , Fumar/fisiopatologia , Adulto JovemRESUMO
Using an original algorithm of examination, we have selected 26 of 74 patients suffering from urine incontinence after prostatic surgery for sling operation. Endoscopic sling was performed in group 1 (n = 17) patients, standard retropubic bulbourethral sling--in group 2 (n = 9) patients. Injuries of large vessels, prostatic gland or urinary bladder were not observed in group 1 while intraoperative injury of the paraprostatic venous plexus (1 case) and perforation of the bladder wall with a needle-perforator (1 case) took place in group 2. One year after surgery in group 1 there were 9 (53%) good outcomes, 4 (23.5%) satisfactory and 4 (23.5%) unsatisfactory results; in group 2--5 (56%), 1 (11%) and 3 (33%) patients, respectively. Our method of videocontrol over movement of the needles in the retropubic space proved to be a reliable technique of reducing the number of intraoperative complications and blood loss. However, the procedure can be used only in patients subjected to transurethral resection of the prostate and not subjected to open surgical interventions on the lesser pelvic organs.
Assuntos
Algoritmos , Ureteroscópios , Ureteroscopia/métodos , Incontinência Urinária/terapia , Idoso , Idoso de 80 Anos ou mais , Perda Sanguínea Cirúrgica/prevenção & controle , Humanos , Masculino , Pessoa de Meia-Idade , Próstata/cirurgia , Estudos Retrospectivos , Bexiga Urinária/cirurgiaRESUMO
The role of urogenical infection in males in present-day urology is demonstrated with a focus on fluoroquinolones efficacy in combined treatment of urogenital infection. The mechanism of action, pharmacokinetics, the spectrum of antimicrobial activity of a novel fluoroquinolone drug avelox are detailed. Avelox use in combined therapy of mono- and mixed infections caused by ureaplasmas, chlamidias, mycoplasms is illustrated by original experience of the authors. Avelox is well tolerated and safe.
Assuntos
Anti-Infecciosos/uso terapêutico , Compostos Aza/uso terapêutico , Quinolinas/uso terapêutico , Uretrite/tratamento farmacológico , Infecções Urinárias/tratamento farmacológico , Adolescente , Adulto , Idoso , Fluoroquinolonas , Humanos , Masculino , Pessoa de Meia-Idade , Moxifloxacina , Resultado do Tratamento , Uretrite/microbiologia , Uretrite/parasitologiaRESUMO
The 62-channel EEG was recorded in control (CI, n = 21) and high anxiety (HA, n = 18) individuals under emotionally neutral (eyes closed, eyes open, and neutral videoclip) as well as under emotionally positive and aversive arousal conditions elicited by affective videoclips. In the present study the first three experimental conditions (eyes closed--eyes open--viewing emotionally neutral films) modeled increasing non-emotional arousal. Findings from this continuum show that in the HA individuals the lowest level of tonic arousal (eyes closed) was associated with stronger right-sided parietotemporal theta1 and beta1 activity. Group differences during cortical arousal increased by sensory stimulation (eyes open, neutral clips presentation) were marked only by persisting favored right hemisphere beta1 activity in high anxiety individuals. Under aversive arousal condition, attended by high intensity experience of emotions of anger, fear, disgust and anxiety, the HA subjects selectively desynchronized the right parietotemporal beta1 power which was initially higher in the control conditions. The obtained findings allow to suggest that peculiarities of right-sided parietotemporal EEG theta1 and beta1 activity in HA individuals under studied emotionally neutral and aversive arousal conditions point to overactivated withdrawal system in "checking" and "control" modes.
Assuntos
Ansiedade/fisiopatologia , Ritmo beta , Lateralidade Funcional , Ritmo Teta , Ansiedade/psicologia , Mapeamento Encefálico , Feminino , Humanos , Masculino , Filmes Cinematográficos , Estimulação LuminosaRESUMO
This study examines the effects of meditation on cardiovascular activity during affective image processing. 22 meditators and 20 controls were shown affective images and were asked either to attend to the images or to down-regulate negative affect (for negative images) or to up-regulate positive affect (for positive images) while continuous cardiovascular activity were recorded. During natural viewing meditators manifested identical pre-stimulus total peripheral resistance (TPR) for all images, whereas controls exhibited greatest,pre-stimulus TPR for negative images and reduced it only in the emotion regulation condition. No between-group differences were revealed for natural viewing of positive images, whereas up-regulation was associated with greater cardiac activation in meditators. The results provide a contribution to the understanding of the mechanisms responsible for the beneficial influence of meditation on cardiovascular risk factors.
Assuntos
Doenças Cardiovasculares/psicologia , Sistema Cardiovascular/fisiopatologia , Meditação/psicologia , Estresse Psicológico/psicologia , Adulto , Cognição/fisiologia , Humanos , Masculino , Fatores de Risco , Resistência Vascular , Yoga/psicologiaRESUMO
The study examines the effects of cognitive reappraisal on the event-related potentials (ERPs) to affective stimuli. Participants (n = 53) were asked either to attend affective images, or to down-regulate negative affect, or to up-regulate positive affect. Reappraisal of negative images was associated with attenuation of the P300 and late positive potential (LPP) over parietal regions, whereas reappraisal of positive images had no significant effect on ERP components. The weak P300 reduction correlated with high personality scores of negative affectivity. We assume that only down-regulation of negative emotions is associated with the changes in primary appraisals, and so far reflected in ERP modulation.
Assuntos
Cognição/fisiologia , Emoções/fisiologia , Potenciais Evocados/fisiologia , Percepção Visual/fisiologia , Adulto , Atenção/fisiologia , Humanos , Masculino , Lobo Parietal/fisiologia , Estimulação Luminosa , FotografaçãoRESUMO
Event-related desynchronization (ERD) and synchronization (ERS) in the theta frequency band was measured while subjects viewed stimuli with differing emotional content (from the International Affective Picture System). A significant valence by hemisphere interaction emerged only in the anterior temporal regions, showing relatively greater right hemisphere ERS for negative and left hemisphere ERS for positive stimuli. In turn, in the posterior brain regions affectively valenced vs neutral stimuli prompted larger extent of ERS against the background of the overall right hemisphere dominance in theta synchronization. The findings document that valence discrimination is associated with the early (200-500 ms poststimulus) time-locked synchronized theta activity as well as hemispheric asymmetries in anterior-posterior direction.
Assuntos
Córtex Cerebral/anatomia & histologia , Córtex Cerebral/fisiologia , Sincronização Cortical , Emoções/fisiologia , Potenciais Evocados/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Ritmo Teta , Adolescente , Adulto , Mapeamento Encefálico , Feminino , Lateralidade Funcional/fisiologia , Humanos , Masculino , Testes Neuropsicológicos , Estimulação Luminosa , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Lobo Temporal/anatomia & histologia , Lobo Temporal/fisiologiaRESUMO
The 62-channel EEG was recorded while control non-alexithymic (n=21) and alexithymic (n=20) participants viewed sequentially presented neutral, pleasant and unpleasant pictures and subjectively rated them after each presentation. The event-related synchronization (ERS) to these stimuli was assessed in the theta-1 (4-6 Hz) and theta-2 (6-8 Hz) frequency bands. The obtained findings indicate that alexithymia influences perception of only emotional stimuli. Over anterior cortical regions alexithymia vs. control individuals in response to both pleasant and unpleasant stimuli manifested decreased left hemisphere ERS in the early test period of 0-200 ms along with enhanced ERS in response to negative vs. positive and neutral stimuli in the right hemisphere at 200-600 ms after stimulus onset. The findings provide the first EEG evidence that alexithymia construct, associated with a cognitive deficit in initial evaluation of emotion, is indexed by disrupted early frontal synchronization in the upper theta band that can be best interpreted to reflect disregulation during appraisal of emotional stimuli.
Assuntos
Sintomas Afetivos/fisiopatologia , Sincronização Cortical/métodos , Emoções/fisiologia , Estimulação Luminosa/métodos , Ritmo Teta/métodos , Sintomas Afetivos/psicologia , Análise de Variância , Sincronização Cortical/psicologia , Eletroencefalografia/métodos , Eletroencefalografia/psicologia , Potenciais Evocados/fisiologia , Feminino , Humanos , Masculino , Ritmo Teta/psicologiaRESUMO
Studies in 20 healthy right-handed subjects analyzed evoked EEG synchronization and desynchronization in the delta, theta1, theta2, alpha1, alpha2, beta1, beta2, beta3, and gamma ranges in response to sequential presentation of stimuli from the International Affective Picture System (IAPS) with low, medium, and high emotional activation impact. Each signal presentation was accompanied by subjective scaling of the extent of its emotional impact. EEG traces were recorded in 62 channels as signals were presented. These experiments showed that the degree of emotional impact of the signal was significantly associated with increases in evoked synchronization in the delta, theta1, theta2, beta1, beta3, and gamma ranges and with the effects of combined changes in evoked synchronization and desynchronization in the alpha2 frequency range. The interhemisphere distribution of evoked changes in power provided evidence that not only the posterior areas of the right hemisphere were involved in analyzing the emotional significance of images, as indicated by changes in evoked theta1 and theta2 synchronization and alpha2 desynchronization, but also the anterior areas of the left hemisphere, as indicated by changes in evoked theta2 synchronization. From the standpoint of affective chronometry, the earliest discrimination of the emotional content of stimuli, regardless of the sign of the emotion, occurred in the lower theta range and was seen at 0-600 msec after the start of stimulus presentation. This process was delayed 600-1000 msec in the theta2, alpha2, and gamma ranges.
Assuntos
Mapeamento Encefálico , Eletroencefalografia/métodos , Emoções/fisiologia , Potenciais Evocados Visuais/fisiologia , Adolescente , Adulto , Eletroencefalografia/classificação , Feminino , Lateralidade Funcional/fisiologia , Humanos , Masculino , Estimulação Luminosa/métodosRESUMO
The 62-channel EEG was recorded while low (LA, n = 18) and high (HA, n = 18) trait-anxious subjects viewed sequentially presented neutral, threatening and pleasant IAPS stimuli. Event-related desynchronization (ERD) and synchronization (ERS) were studied in the delta, theta1, theta2, alpha1, alpha2, beta1, beta2, beta3, and gamma frequency bands. Between-group differences, related to stimulus emotionality, were linked to theta1 and theta2 bands. In the low theta at prefrontal sites in the test period of 100-700 ms after stimulus onset HA exhibited relative predominance of the left hemisphere in response to both threatening and pleasant stimuli, whereas LA yielded larger right than left hemisphere activity in response to all the three stimulus categories. In the upper theta band between group differences were associated with posterior cortical regions and the test period of 0-1000 ms after stimulus onset: HA exhibited the largest ERS to threatening, whereas LA prompted the largest ERS to pleasant stimuli. Finally, according to the ERD data, in the alpha1 band HA participants in comparison with LA revealed enhanced left hemisphere activation in response to all the stimulus categories. It is suggested that as it is indexed by theta-ERS relative predominance of the left hemisphere at prefrontal sites along with the largest bilateral activity of posterior cortical regions (i.e., enhanced higher order visual processing) to threatening stimuli could form the basis for general bias towards threatening information in HA at the very early stages of emotional processing.