989 resultados para atividade proteolítica
Resumo:
Diabetes Mellitus (DM) affected approximately 171 million people in the world in the year 2000 as described by the World Health Organization (WHO). Because DM is a multisystem disease it can cause several complications especially those related to the cardiovascular system. The Peripheral Arterial Disease (PAD) of the lower limbs and the Diabetic Distal Symmetric Polyneuropathy (DDSP) can affect the DM patient causing consequences as the diabetic foot and eventually amputations. The main objective of this study was to determine the prevalence of PAD and sensorial impairment in 73 type 2 DM (DM2) patients and also assess the impact of PAD on quality of life, level of physical activity and body composition. For clinical assessment it was used: the ankle-brachial index (ABI); quantitative sensorial test for tactile sensibility (ST), pain (SD), vibration (SV); Achilles tendon reflex (RA); quality of life questionnaire (SF-36); modified Baecke physical activity questionnaire and bioelectric impedance. Prevalence of PAD in the studied population was 13.7%. ABI was inversely correlated to age (p=0,03; rhô= -0,26), diabetes duration (p=0,02; rhô= -0,28) and blood pressure (p= 0,0007; rhô= -0,33). There were lower scores for physical health summary on the SF-36 in DM2 patients; however, the presence of PAD predominantly mild did not significantly impact quality of life, body composition or physical activity level assessed by questionnaire. Fourteen patients (19.2%) present bilateral and symmetrical alterations in two or more sensorial tests compatible to DPN diagnosis. Abnormalities in ST, SD and SV were present in 27.3%, 24.6% and 8.2%; respectively. There was association of results from ST abnormalities with RA and mainly with SD, suggesting the importance of 10g monofilament use in DM2 routine assessment. In conclusion, the prevalence of PAD in subclinical DM2 was slightly higher compared to the general population and in agreement to previously published data in DM patients. The PAD severity was predominantly mild and still without repercussion on quality of life and body composition. Our study demonstrated a significant prevalence of both PAD and DPN in DM2 without previous diagnosis of these complications and indicates the necessity of early preventive and therapeutic interventions for this population
Resumo:
The reduction of physiological capacity present in the process of aging causes a marked decline in lung function. The exercise does promote several positive changes in the physical health of people and protect the cardiorespiratory function. The aim of this study was to investigate the effects of a program of Pilates exercices on the strengh and electrical activity of respiratory muscles of elderly. This is a randomized, controlled clinical trial, evaluating 33 elderly aged 65 and 80 (70.88 ± 4.32), healthy, sedentary, without cognitive impairment and able the practice physical activity. The sample was divided into two groups, one experimental group with 16 elderly women who did Pilates exercises and a control group (17) that was not submitted to the exercises, but received educational booklets on aging and health care. The elderly were evaluated initially and after a period of three months, taking into account the Maximal Inspiratory Pressure (MIP) and Maximal Expiratory Pressure (MEP), obtained by Manovacuometry and intensity of EMG activity was measured using the values of Root Mean Square (RMS) for the diaphragm and rectus abdominis muscles, during the course of diaphragmatic breathing and MIP maneuver. Data were analyzed using SPSS version 17.0. For all tests, we used a significance level or p value < 0.05 and confidence interval 95%. RMS in diaphragm and rectus abdominis muscles in both tests increased, but the data were significant for the rectus abdominis during diaphragmatic breathing (p = 0.03) and the diaphragm during the MIP maneuver (p = 0.01). There was no significant variation of the MIP and MEP. Pilates exercises were responsible for increasing the electrical activation of the diaphragm and rectus abdominis muscles in a group of healthy elderly, but had no influence on changes in strength of respiratory muscles
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The cerebral vascular accident is a neurological dysfunction of vascular origin that leds to development of motor sensibility, cognitive, perceptive and language deficits. Despite the fact that the main sleep disorders in stroke patients are well known, it is still necessary to analyze which mechanisms of regulation of sleep and wakefulness are affected. The objective of this study was to evaluate the changes in the circadian and homeostatic control of sleep-wakefulness in stroke patients and the correlations with quality of life and level of physical activity. The study analyzed 22 stroke patients (55± 12 years old) and 24 healthy subjects (57 ±11 years old). The instruments used in this study were questionnaires on sleep quality, daytime sleepiness, quality of life, physical activity level and the actigraphy. The data were analyzed using the Student `t test, Mann-Whitney test, ANOVA and Spearman's correlation tests. The results showed stability in the sleep-wake circadian expression with changes in the amplitude of the rhythm. However, significant changes were found related to the homeostatic component characterized by increased sleep duration, increased latency, fragmented sleep and lower sleep efficiency. Additional data showed decreased quality of sleep and increased daytime sleepiness, as well as decreased quality of life and level of physical activity. The results indicate that the interaction of circadian and homeostatic control of sleep-wake is compromised and the main reason might be because of the homeostatic component and the lower activity level resulting from the brain damage. Thus, further studies may be developed to evaluate whether behavioral interventions such as increased daytime activity and restriction of sleep during the day can influence the homeostatic process and its relation to circadian component, resulting in improved quality of nocturnal sleep in stroke patients
Resumo:
Asthma treatment aims to achieve and maintain the control of the disease for prolonged periods. Inspiratory muscle training (IMT) may be an alternative in the care of patients with asthma, and it is used as a complementary therapy to the pharmacological treatment. Thus, the aim of this study was to investigate the effects of a domiciliary program of IMT on the electromyographic activity of the respiratory muscles in adults with asthma. This is a clinical trial in which ten adults with asthma and ten healthy adults were randomized into two groups (control and training). The electrical activity of inspiratory muscles (sternocleidomastoid (ECM) and diaphragm) was obtained by a surface electromyography. Furthermore, we assessed lung function (spirometry), maximal inspiratory pressure - MIP - (manometer). The functional capacity was evaluated by six minute walk test. Participants were assessed before and after the IMT protocol of 6 weeks with POWERbreathe® device. The training and the control groups underwent IMT with 50% and 15 % of MIP, respectively. The sample data were analyzed using SPSS 20.0, attributing significance of 5 %. Were used t test, ANOVA one way and Pearson correlation. It was observed an increase in MIP, after IMT, in both training groups and in healthy sham group (P < 0.05), which was accompanied by a significant increase in ECM activity during MIP in healthy training group (1488 %) and in asthma training group (ATG) (1186.4%). The ATG also showed a significant increase in diaphragm activity in basal respiration (48.5%). Functional capacity increased significantly in the asthma sham group (26.5 m) and in the asthma training group (45.2 m). These findings suggest that IMT promoted clinical improvements in all groups, especially the ATG, which makes it an important complementary treatment for patients with asthma
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The association of Virtual Reality (VR) to clinical practice has become common in the recent years, showing to be an additional tool on health care, especially for elderly. Its use has been related to higher therapeutic adhesion levels and well being sensation. Such emotional based aspects are often observed by subjective tools of relative validity. This study analyzed the immediate effects of varied VR contexts balance training over emotional behavior, which was observed under peaks of maximum expression of EEG waves. Methodology: 40 individuals, divided in two groups, both gender, 20 young and 20 elderly, were submitted to a 60 minutes intervention, including balance training under VR. The first 25 minutes referred to initial evaluation, general orientation and cognitive assessment by the use of Mini Mental. The next ten minutes were designated to the avatar creation and tutorial video presentation. Through the following 20 minutes, the individuals from both groups were exposed to the exact same sequence of games under virtual contexts, while submitted to electroencephalography by Emotiv EPOC® focusing Adhesion, Frustration and Meditation states. The virtual interface was provided by the Nintendo® game, Wii Fit Plus, with the scenarios Balance Bubble (1), Penguin (2), Soccer (3), Tight Rope (4) and Table Tilt (5). Finally, a questionnaire of personal impressions was applied on the 5 minutes left. Results: data collected showed 64,7% of individuals from both groups presented higher concentration of adhesion peaks on Balance Bubble game. Both groups also presented similar behavior regarding meditation state, with marks close to 40%, each, on the same game, Table Tilt. There was divergence related to the frustration state, being the maximum concentration for the young group on the Soccer game (29,3%), whilst the elderly group referred highest marks to Tight Rope game (35,2%). Conclusion: Findings suggest virtual contexts can be favorable to adhesion and meditation emotional patterns induction, regardless age and for both sexes, whilst frustration seems to be more related to cognitive motor affordance, likely to be influenced by age. This information is relevant and contributes to the orientation for the best choice of games applied in clinical practice, as for other studies regarding this topic
Resumo:
Este artigo é resultado de estudos teóricos e pretende apresentar algumas contribuições ao estudo da psicologia histórico-cultural do desenvolvimento, mais especificamente no que se refere à relação existente entre as categorias de trabalho e atividade. Estudos desta natureza são importantes para psicólogos, pedagogos e demais profissionais envolvidos direta ou indiretamente com a prática educativa, na busca por compreender o problema da periodização do desenvolvimento em uma perspectiva não naturalizante. Nesta direção, a categoria de atividade principal mostra-se central como força motriz do processo de desenvolvimento humano, portanto encontra-se estreitamente ligada ao lugar que cada indivíduo ocupa na sociedade de classes bem como às condições objetivas de sua existência material. O estudo do desenvolvimento coincide com o estudo da pessoa concreta, imersa numa trama de relações sociais e num sistema político e econômico; enfim, outra coisa não é senão o estudo da história objetivada em cada indivíduo particular.
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Shrimp farming in Brazil is a consolidated activity, having brought economical and social gains to several states with the largest production concentrated in the northeast. This fact is also reflected in higher feed intake, necessitating a more efficient feed management. Currently, management techniques already foresee food loss due to molting. In this sense, studies relating shrimp s digestive physiology, molting physiology and behavioral response of shrimp feed can optimize the feed management. Thus, our study aimed to evaluate the behavioral response of the marine shrimp L. vannamei (Crustacea: Penaeidae) in accordance with the stages of moulting cycle and feeding schedules based on higher or lower activity of proteolytic digestive enzymes; also, to investigate the influence of feeding schedule on hepatosomatic index and non-specific and specific protease activity (trypsin). Experiments were carried out at the Laboratory of Shrimp Behavioral Studies at UFRN in partnership with the Laboratory of Enzimology UFPE. Juveniles of L. vannamei weighting 5.25 g (+ 0.25 g) were kept in aquaria at a density of 33 shrimp m -2. In the first experiment, shrimp were fed in the light phase or in the dark phase for 8 days; in the ninth day, the animals were observed for 15 minutes every hour during the 12 hours of each phase of the photoperiod. We recorded the frequency of inactivity, exploration, food intake, burrowing, swimming and crawling behavior. At the end of the 12th observation session, the shrimp were sacrified and classified by the method of setogenesis in the molt cycle stages A, B, C, D0, D1, D2 or D3. We found that the shrimp in A stage show high levels of inactivity. Moreover, the frequency of food intake was very low. The shrimp in D3 stage also had low food intake and high inactivity associated with elevated frequencies of burrowing. In the second experiment, shrimp were kept in physiological acclimation to experimental conditions for 28 days, distributed in 12 treatments in the light phase and 12 treatments in the dark phase. In the end, the animals were sacrified and dissected to assess non-specific and specific protease activity (trypsin) activity. In general, these parameters did not vary among animals fed in the light phase and those fed in the dark phase. However, significant differences were found in the activity of specific and nonspecific proteases in relation to food treatment. In the light phase, the major proteolytic activities converged to 10 hours after the start of the light phase, while the lowest activities converged to 6 hours after the beginning of this phase. In the dark phase, the highest enzyme activity converged to 12 hours after the onset of phase, while the lowest activities converged to 3 hours after the onset of phase. In the third experiment, we sought to evaluate the behavioral responses of shrimp in relation to dietary treatments based on higher or lower activity of proteolytic enzymes, considering the results of the second experiment. The behavioral categories observed were the same as the ones in the first experiment, with observations of 30 minutes (15min before and 15min after food supply). We found variation in behavioral responses as a function of the treatments, with greater intake of food in shrimp fed during the period of greatest activity of proteolytic enzymes, in the light phase. Thus we see that periodic events associated with the shrimp s physiology interfere in their behavioral responses, revealing situations that are more adjustable to the provision of food, and consequently optimizing feeding management
Resumo:
The temporal allocation of the active phase in relation to light and dark cycle (LD) changes during puberty in humans, degus, rats and rhesus. In marmosets, the animal model used in several biomedical researches, there is evidence of a delay at the beginning of the active phase and an increase in total daily activity after onset of puberty. However, as this aspect was evaluated in animals maintained in natural environmental conditions, it was not possible to distinguish between the effects of puberty and of seasonality. Furthermore, as motor activity is the result of different behaviors in this species, it is also important to characterize the diurnal distribution of other behaviors in juvenile stage. With the aim of characterizing the circadian rhythm of motor activity and the diurnal profile of affiliative behavior in marmosets, the motor activity of 5 dyads juveniles between 4 and 12 months of age and their parents was recorded continuously for actímetro. The families were maintained under artificial LD 12:12 h, constant temperature and humidity. The duration of grooming behavior, proximity and social play among juveniles was recorded 2 times a week in sessions of 15 minutes each hour of the active phase. Afetr onset of puberty in juvenile, it was observed that there was no change in the parameters of circadian motor activity rhythm which were common to most animals. Despite the absence of pubertal modulation, it was observed that the circadian activity profiles have stronger synchrony between individuals of the same family than that of different families, which may indicate that the circadian activity rhythm was modulated by the dynamics of social interactions. In relation to age, the total daily activity and the ratio between evening and morning activity (EA/MA) were higher in juveniles than in adults, which may be associated with differences in the circadian timing system between age groups. Furthermore, the onset of the 10 consecutive hours of higher activity (M10) occurred earlier in adult males than in other members of the group, probably as a way to avoid competition for resources in one of the first activities of the day that is foraging. During the juvenile stage, there was an increase in total daily activity that may be associated with increased motor ability of juveniles. In addition to the circadian activity rhythm, the daytime profile of proximity and social play behaviors was similar between the 5th and 12th month of life of juveniles, in which the interval between 7- 10 h in the morning showed the highest values of proximity and lower values of play social. Moreover, the duration of the grooming showed a similar distribution to adults from the 8th month, wherein the higher values occurring at the interval between 11 14 h of day. Considering the results, the parameters of the circadian activity rhythm had a greater influence of social factors than puberty. In relation to age, there were no changes related to the allocation of the active phase in relation to the LD cycle, but total daily activity, the ratio AV/AM and the start of the M10 is possible to observe differences between juveniles and adults
Resumo:
Kerodon rupestris (rock cavy, mocó) is an endemic caviidae of Brazilian northeast that inhabits rocky places in the semi arid region. The aim of this study was to characterize the activity/rest rhythm of the rock cavy under 12:12 h LD cycle and continuous light. In the first stage, seven animals were submitted to two light intensities (LD; 250:0 lux and 400:0 lux; 40 days each intensity). In the second stage four males were kept for 40 days in LD (470:<1 lux), for 18 days in LL 470 lux (LL470) and for 23 days in red dim light below 1 lux (LL<1). In the third stage three males were initially kept in LD 12:12 h (450:<1 lux) and after that in LL with gradual increase in light intensity each 21 days (<1 lux LL<1; 10 lux-LL10; 160 lux LL160; 450 lux LL450). In the fourth stage it was analyzed the motor activity of 16 animals in the first 10 days in LD. Motor activity was continuously recorded by passive infrared movement sensors connected to a computer and totaled in 5 min bins. The activity showed circadian and ultradian rhythms and activity peaks at phase transitions. The activity and the rest occurred in the light as well as in the dark phase, with activity mean greater in the light phase for most of the animals. The light intensity influenced the activity/rest rhythm in the first three stages and in the first stage the activity in 400 lux increased in four animals and decreases in two. In the second stage, the tau for 3 animals in LL470 was greater than 24 h; in LL<1 it was greater than 24 h for one and lower for two. In the third stage the tau decreased with the light intensity increase for animal 8. During the first days in the experimental room, the animals did not synchronize to the LD cycle with activity and rest occurring in both phases. The results indicate that the activity/rest rhythm of Kerodon rupestris can be affected by light intensity and that the synchronization to the LD cycle results from entrainment as well as masking probably as a consequence of the action of two or more oscillators with low coupling strength
Resumo:
Sotalia guianensis is a small cetacean of the Delphinidae family, with coastal habits and whose area of distribution ranges from Florianópolis (27º35'S, 48º34'W), in Brazil, to Honduras (15º58'N, 85º42'W). At Pipa beach, on the south coast of RN state, in Brazil, the species occur throughout the year. The present study was carried out in two bays, which are bordered by cliffs. The animals were monitored from vantage points, using the "Ad libitum" and "all the occurrences" methods; during the years of 1999 and 2004. The study was divided in 4 chapters: Behavioral standards of two populations of gray dolphin, (Sotalia guianensis, Van Benédén, 1864) in the northeast of Brazil; Aerial activity of the gray dolphin: its possible function and the influence of environmental and behavioral factors; The influence of daily and monthly variation of the tides, of the period of the day and group size on the gray dolphin forage activity; kleptoparasitism interactions of frigatebird (Fregata magnificens, Mattheus, 1914) during the gray dolphin forage activity. The results have shown that the gray dolphin has a varied and complex behavioral repertoire. The leap is the most frequent behavior; the aerial activity is diffuse during daylight and is influenced by some factors, such as the level of the tide and social factors. The gray dolphin, when in the bay, most frequently feeds isolate or in small groups. The forage is diffuse during daylight; however, being more frequent in the morning and is influenced by the daily and monthly variation of the tide. At Pipa beach, kleptoparasitarian interactions were registered between the gray dolphin and the frigatebird (Fregata magnificens). The frigatebird forage strategy consists basically of two ways: to fly over great extensions searching for dead fish and to steal food (kleptoparasitism). These interactions were predominantly carried out between immature and female adult birds and adult and immature dolphins, and occurred during daylight. The present study can be considered an initial landmark to a better knowledge on the gray dolphin surface behavior, especially regarding the aerial behavioral repertoire and forage strategy of this species. However, it is necessary to continue these studies, so that we can understand better the complex social life of these animals and thus create effective measures for its conservation
Resumo:
The principal zeitgeber for most of species is the light-dark photocycle (LD), though other environment factors as food availability, temperature and social cues may act. Daily adjustment of the circadian pacemaker may result from integration of environmental photic and non-photic cues with homeostatic cues. Characterization of non-photic effects on circadian timing system in diurnal mammals is scarce in relation to nocturnal, especially for ecologically significant cues. Thus, we analyzed the effect of conspecific vocalizations and darkness on circadian activity rhythm (CAR) in the diurnal primate Callithirx jacchus. With this objective 7 male adults were isolated in a room with controlled illumination, temperature (26,8 ± 0,2°C) and humidity (81,6 ± 3,6%), and partial acoustic isolation. Initially they were under LD 12:12 (~300:2 lux), and subsequently under constant illumination (~2 lux). Two pulses of conspecific vocalizations were applied in total darkness, separated by 22 days, at 7:30 h (external time) during 1 h. They induced phase delays at circadian times (CTs) 1 and 10 and predominantly phase advances at CTs 9 and 15. After that, two dark pulses were applied, separated by 14 days, during 1 h at 7:30 h (external time). These pulses induced phase delays at CTs 2, 3 and 18, predominantly phase advances at CTs 8, 10 and 19, and no change at CT 14. However, marmosets CAR showed oscillations in endogenous period and active phase duration influenced by vocalizations from animals outside the experimental room, which interfered on the phase responses to pulses. Furthermore, social masking and relative coordination with colony were observed. Therefore, phase responses obtained in this work cannot be attributed only to pulses. Afterwards, pulses of conspecific vocalizations were applied in total darkness at 19:00 h (external time), during 1 h for 5 consecutive days, and after 21 days, for 30 consecutive days, on attempt to synchronize the CAR. No animal was synchronized by these daily pulses, although oscillations in endogenous period were observed for all. This result may be due to habituation. Other possibility is the absence of social significance of the vocalizations for the animals due to random reproduction, since each vocalization has a function that could be lost by a mixture of sounds. In conclusion, conspecific vocalizations induce social masking and relative coordination in marmosets CAR, acting as weak zeitgeber
Resumo:
Most of ontogenetic studies on circadian timing system have been developed on infants, adults and elderly. The puberty has not been a stage of life few studied, except for researches in human adolescents, that presents phase delay in sleep-wake cycle. However, few studies have focused on the basis of this circadian change due to methodological difficulties. Thus, an animal model to study the sleep-wake cycle at puberty is essential. In the common marmoset, a social primate, the circadian activity periodicity stabilizes around 4 months (juvenile stage) and the 8h period component has a seasonal variation. Puberty stage of this species begins near the 8th month of age in males and near the 7th month in females with 7 months of duration. With the aim to characterize the circadian motor activity rhythm during puberty in marmosets (Callithrix jacchus) the motor activity was continuous registered by actiwatches in 6 animals between 5-12 months. Since the social factor influence the behavior of this specie, behavioral observations were realized in 30 minutes windows twice/week to a general evaluation of the influence social interactions dynamic across experiment. Determination of puberty onset was done by fecal progesterone and estrogens in females, and androgens in males. From the analysis of the multiple regression test was selected a model that evaluate age and seasonal variables effect on the activity rhythm according to the higher explanation coefficient. The total activity was the only parameter influenced by age. Moreover, the activity onset was the parameter more explained by the model, and the sunrise was the factor that most influenced it. After the puberty onset, 2 dyads advanced the activity onset. The activity total decreased in 1 dyad and increased in 2 dyads. This increase may be related to the birth of infants in these families. The motor activity circadian component stabilized later in 1 dyad, coinciding with the puberty onset of these animals, while bimodality, caused by the 8 h component, was modulated by seasonality. The agonistic behavior was not evaluated due to reduced number of events. There were changes across ages in affiliative behavior of contact in 1 dyad, grooming done in 1 animal and grooming received in 2 animals. Although there is evidence of puberty effect on the activity motor rhythm, the photoperiodic fluctuations influenced the rhythm. Therefore is not possible to affirm if the puberty modulate the activity rhythm in marmosets
Resumo:
In rodents, the suprachiasmatic nucleus (SCN) and the intergeniculate leaflet (IGL) are the main components of the circadian system. The SCN is considerate the site of an endogenous biological clock because can to generate rhythm and to synchronize to the environmental cues (zeitgebers) and IGL has been related as one of the main areas that modulate the action of SCN. Both receive projections of ganglion cells of retina and this projection to SCN is called retinohypothalamic tract (RHT). Moreover, the IGL is connected with SCN through of geniculohypothalamic tract (GHT). In primates (include humans) was not still demonstrated the presence of a homologous structure to the IGL. It is believed that the pregeniculate nucleus (PGN) can be the answer, but nothing it was still proven. Trying to answer that question, the objective of our study is to do a comparative analysis among PGN and IGL through of techniques immunohystochemicals, neural tracers and FOS expression after dark pulses. For this, we used as experimental model a primate of the new world, the common marmoset (Callithrix jacchus). Ours results may contribute to the elucidation of this lacuna in the circadian system once that the IGL is responsible for the transmission of nonphotic information to SCN and participate in the integration between photic and nonphotic stimulus to adjust the function of the SCN. In this way to find a same structure in primates represent an important achieve in the understanding of the biological rhythms in those animals
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In most cultures, dreams are believed to predict the future on occasion. Several neurophysiological studies indicate that the function of sleep and dreams is to consolidate and transform memories, in a cyclical process of creation, selection and generalization of conjectures about the reality. The aim of the research presented here was to investigate the possible adaptative role of anticipatory dreams. We sought to determine the relationship between dream and waking in a context in which the adaptive success of the individual was really at risk, in order to mobilize more strongly the oneiric activity. We used the entrance examination of the Federal University of Rio Grande do Norte (UFRN) as a significant waking event in which performance could be independently quantified. Through a partnership with UFRN, we contacted by e-mail 3000 candidates to the 2009 examination. In addition, 150 candidates were approached personally. Candidates who agreed to participate in the study (n = 94) completed questionnaires specific to the examination and were asked to describe their dreams during the examinaton period. The examination performance of each candidate in the entrance examination was provided by the UFRN to the researcher. A total of 45 participants reported dreams related to the examination. Our results show a positive correlation between performance on the examination and anticipatory dreams with the event, both in the comparison of performance on objective and discursive, and in final approval (in the group that not dreamed with the exam the rate of general approval, 22,45%, was similar to that found in the selection process as a whole, 22.19%, while for the group that dreamed with the examination that rate was 35.56%). The occurrence of anticipatory dreams reflectes increased concern during waking (psychobiological mobilization) related to the future event, as indicated by higher scores of fear and apprehension, and major changes in daily life, in patterns of mood and sleep, in the group that reported testrelated dreams. Furthermore, the data suggest a role of dreams in the determination of environmentally relevant behavior of the vigil, simulating possible scenarios of success (dream with approval) and failure (nightmares) to maximize the adaptive success of the individual
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The currently accepted model of sensory processing states that different senses are processed in parallel, and that the activity of specific cortical regions define the sensorial modality perceived by the subject. In this work we used chronic multielectrode extracellular recordings to investigate to which extent neurons in the visual and tactile primary cortices (V1 and S1) of anesthetized rats would respond to sensory modalities not traditionaly associated with these cortices. Visual stimulation yielded 87% of responsive neurons in V1, while 82% of S1 neurons responded to tactile stimulation. In the same stimulation sessions, we found 23% of V1 neurons responding to tactile stimuli and 22% of S1 neurons responding to visual stimuli. Our data supports an increasing body of evidence that indicates the existence multimodal processing in primary sensory cortices. Our data challenge the unimodal sensory processing paradigm, and suggest the need of a reinterpretation of the currently accepted model of cortical hierarchy.