41 resultados para Trigeminal main sensory nucleus


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It is well known that the Neolithic transition spread across Europe at a speed of about 1 km/yr. This result has been previously interpreted as a range expansion of the Neolithic driven mainly by demic diffusion (whereas cultural diffusion played a secondary role). However, a long-standing problem is whether this value (1 km/yr) and its interpretation (mainly demic diffusion) are characteristic only of Europe or universal (i.e. intrinsic features of Neolithic transitions all over the world). So far Neolithic spread rates outside Europe have been barely measured, and Neolithic spread rates substantially faster than 1 km/yr have not been previously reported. Here we show that the transition from hunting and gathering into herding in southern Africa spread at a rate of about 2.4 km/yr, i.e. about twice faster than the European Neolithic transition. Thus the value 1 km/yr is not a universal feature of Neolithic transitions in the world. Resorting to a recent demic-cultural wave-of-advance model, we also find that the main mechanism at work in the southern African Neolithic spread was cultural diffusion (whereas demic diffusion played a secondary role). This is in sharp contrast to the European Neolithic. Our results further suggest that Neolithic spread rates could be mainly driven by cultural diffusion in cases where the final state of this transition is herding/pastoralism (such as in southern Africa) rather than farming and stockbreeding (as in Europe)

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We analyze the timing of photons observed by the MAGIC telescope during a flare of the active galactic nucleus Mkn 501 for a possible correlation with energy, as suggested by some models of quantum gravity (QG), which predict a vacuum refractive index similar or equal to 1 + (E/M-QGn)(n), n = 1, 2. Parametrizing the delay between gamma-rays of different energies as Delta t = +/-tau E-1 or Delta t = +/-tau E-q(2), we find tau(1) = (0.030 +/- 0.012) s/GeV at the 2.5-sigma level, and tau(q) = (3.71 +/- 2.57) x 10(-6) s/GeV2, respectively. We use these results to establish lower limits M-QG1 > 0.21 X 10(18) GeV and M-QG2 > 0.26 x 10(11) GeV at the 95% C.L. Monte Carlo studies confirm the MAGIC sensitivity to propagation effects at these levels. Thermal plasma effects in the source are negligible, but we cannot exclude the importance of some other source effect.

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The Nucleus accumbens (Nacc) has been proposed to act as a limbic-motor interface. Here, using invasive intraoperative recordings in an awake patient suffering from obsessive-compulsive disease (OCD), we demonstrate that its activity is modulated by the quality of performance of the subject in a choice reaction time task designed to tap action monitoring processes. Action monitoring, that is, error detection and correction, is thought to be supported by a system involving the dopaminergic midbrain, the basal ganglia, and the medial prefrontal cortex. In surface electrophysiological recordings, action monitoring is indexed by an error-related negativity (ERN) appearing time-locked to the erroneous responses and emanating from the medial frontal cortex. In preoperative scalp recordings the patient's ERN was found to be signifi cantly increased compared to a large (n = 83) normal sample, suggesting enhanced action monitoring processes. Intraoperatively, error-related modulations were obtained from the Nacc but not from a site 5 mm above. Importantly, crosscorrelation analysis showed that error-related activity in the Nacc preceded surface activity by 40 ms. We propose that the Nacc is involved in action monitoring, possibly by using error signals from the dopaminergic midbrain to adjust the relative impact of limbic and prefrontal inputs on frontal control systems in order to optimize goal-directed behavior.

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The ventral striatum / nucleus accumbens has been implicated in the craving for drugs and alcohol which is a major reason for relapse of addicted people. Craving might be induced by drug-related cues. This suggests that disruption of craving-related neural activity in the nucleus accumbens may significantly reduce craving in alcohol-dependent patients. Here we report on preliminary clinical and neurophysiological evidence in three male patients who were treated with high frequency deep brain stimulation of the nucleus accumbens bilaterally. All three had been alcohol dependent for many years, unable to abstain from drinking, and had experienced repeated relapses prior to the stimulation. After the operation, craving was greatly reduced and all three patients were able to abstain from drinking for extended periods of time. Immediately after the operation but prior to connection of the stimulation electrodes to the stimulator, local field potentials were obtained from the externalized cables in two patients while they performed cognitive tasks addressing action monitoring and incentive salience of drug related cues. LFPs in the action monitoring task provided further evidence for a role of the nucleus accumbens in goal-directed behaviors. Importantly, alcohol related cue stimuli in the incentive salience task modulated LFPs even though these cues were presented outside of the attentional focus. This implies that cue-related craving involves the nucleus accumbens and is highly automatic.

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The effect of pork fat reduction (from 44% to 20% final fat content) and its partial substitution by sunflower oil (3% addition) on the physicochemical, instrumental and sensory properties throughout storage time of small caliber non-acid fermented sausages (fuet type) with reduced sodium content (with partial substitution of NaCl by KCl and K-lactate) and without direct addition of nitrate and nitrite (natural nitrate source used instead), was studied. Results showed that sausages with reduced fat (10% initial fat content) and with acceptable sensory characteristics can be obtained by adding to the shoulder lean (8% fat content) during the grinding, either 3.3% backfat (3% fat content) or 3% sunflower oil, both previously finely comminuted with lean. Furthermore, sunflower oil showed to be suitable for partial pork backfat substitution in very lean fermented sausages, conferring desirable sensory properties similar to those of sausages with standard fat content. The sensory quality of the sausages was maintained after three-month cold storage in modified atmosphere.

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Educators who are currently beginning their professional career at any level of the educationalsystem and who will likely have to work during the next thirty to forty years will be takingpart in the education of individuals who, with the permission of prophets and doomsayers,will live part of their lives in the 22nd century. That long but simple statement causes a bit ofvertigo as well as a good amount of reflection on the part of we educators who were trainedin the 20th century, are working in the 21st century, and are responsible for preparing peopleto build a tomorrow that is already today (Millán and Sancho, 1995). This is the starting pointof our research groups’ interest in exploring how men and women who have graduated fromteacher education programs with specializations in infant and primary education learn to beteachers, and how they establish and position themselves as teachers during their university studies and the first years of their professional life...

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Educators who are currently beginning their professional career at any level of the educationalsystem and who will likely have to work during the next thirty to forty years will be takingpart in the education of individuals who, with the permission of prophets and doomsayers,will live part of their lives in the 22nd century. That long but simple statement causes a bit ofvertigo as well as a good amount of reflection on the part of we educators who were trainedin the 20th century, are working in the 21st century, and are responsible for preparing peopleto build a tomorrow that is already today (Millán and Sancho, 1995). This is the starting pointof our research groups’ interest in exploring how men and women who have graduated fromteacher education programs with specializations in infant and primary education learn to beteachers, and how they establish and position themselves as teachers during their university studies and the first years of their professional life...

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Educators who are currently beginning their professional career at any level of the educationalsystem and who will likely have to work during the next thirty to forty years will be takingpart in the education of individuals who, with the permission of prophets and doomsayers,will live part of their lives in the 22nd century. That long but simple statement causes a bit ofvertigo as well as a good amount of reflection on the part of we educators who were trainedin the 20th century, are working in the 21st century, and are responsible for preparing peopleto build a tomorrow that is already today (Millán and Sancho, 1995). This is the starting pointof our research groups’ interest in exploring how men and women who have graduated fromteacher education programs with specializations in infant and primary education learn to beteachers, and how they establish and position themselves as teachers during their university studies and the first years of their professional life...

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Educators who are currently beginning their professional career at any level of the educationalsystem and who will likely have to work during the next thirty to forty years will be takingpart in the education of individuals who, with the permission of prophets and doomsayers,will live part of their lives in the 22nd century. That long but simple statement causes a bit ofvertigo as well as a good amount of reflection on the part of we educators who were trainedin the 20th century, are working in the 21st century, and are responsible for preparing peopleto build a tomorrow that is already today (Millán and Sancho, 1995). This is the starting pointof our research groups’ interest in exploring how men and women who have graduated fromteacher education programs with specializations in infant and primary education learn to beteachers, and how they establish and position themselves as teachers during their university studies and the first years of their professional life...

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Music is one of the most pleasant human experiences, even though it has no direct biological advantage. However little is known about individual differences in how people experience reward in music-related activities. The goal of the present study was to describe the main facets of music experience that could explain the variance observed in how people experience reward associated with music. To this end we developed the Barcelona Music Reward Questionnaire (BMRQ), which was administrated to three large samples. Our results showed that the musical reward experience can be decomposed into five reliable factors: Musical Seeking, Emotion Evocation, Mood Regulation, Social Reward, and Sensory-Motor. These factors were correlated with socio-demographic factors and measures of general sensitivity to reward and hedonic experience. We propose that the five-factor structure of musical reward experience might be very relevant in the study of psychological and neural bases of emotion and pleasure associated to music.