1,721,073 research outputs found
Medial prefrontal cortex early lesion effects on classical conditioned bradycardia
No full textThe effects of medial prefrontal cortex early lesion (mPFl) on classical conditioned bradycardia (CB) were studied in adult rabbits. In lesioned rabbits, baseline HR, orienting and conditioned HR responses were similar to controls. Since mPFl alone does not affect CB, while it is known to prevent the HR increments produced by a concomitant early cerebellar vermal ablation, medial prefrontal cortex must be involved in the reorganization of the CB control mechanisms following early cerebellar vermal ablation
Manipulation of attention in highly and low hypnotizable individuals: a study on verbal priming
No full textThis study investigated the effects of manipulation of attention on verbal priming in highly (Highs) and low (Lows) hypnotizable individuals. Priming was evaluated via the word-stem completion task (WSCT). The experimental paradigm consisted of one condition in full-attention and in two conditions with colored words in which attention was directed, respectively, only to the color and to both color and word. No significant differences between Highs and Lows were found in none of the three attentional conditions. However, during encoding in full-attention, Highs showed shorter reaction times (RTs) than Lows. This is in accord with previous evidence of faster simple and choice RTs in Highs than in Lows, and suggests hypnotizability-related differences in arousal, likely driven by a different cognitive control activity. Also, Highs' self-report of interference of color-naming on word-reading suggests possible differences between Highs and Lows in cognitive activity related to mental effort
Role of the medial prefrontal cortex in the development of the conditioned bradycardia in rabbits with lesions of the cerebellar vermis.
No full textThe effects on the expression of conditioned bradycardia of pairing an early (fourth postnatal day) cerebellar vermal lesion with a lesion of the medial prefrontal cortex (mPFC) were studied in adult New Zealand rabbits. In the conditioning procedure, an auditory stimulus (5 s, 1000 Hz) served as a conditioning stimulus (CS) and a train of electrical impulses applied to the ear (500 ms, 100 Hz, 1.5 mA) was used as the unconditioned stimulus (US). Heart rate (HR) responses exhibited by rabbits with the early double lesion (PFCBs) during orientation (CS-alone) and conditioning (CS-US paired) were analyzed and compared with those shown by unoperated controls as well as by a group of animals in which a cerebellar lesion alone had been performed on the fourth postnatal day (CBs). In all the experimental groups vermal lesions were localized in the cortex of lobules V-VII and the underlying white matter. As for mPFC ablation, the lesioned area involved the agranular precentral region (Brodmann's area 8), the anterior cingulate cortex (Brodmann's area 24) and the prelimbic area (Brodmann's area 32). All the experimental animals had a normal baseline HR as well as a marked orientation response, both comparable with those exhibited by controls. In contrast, while CB rabbits showed an increase in the amplitude of the conditioned bradycardic response when compared with controls, the HR conditioned response of PFCB animals was comparable to that exhibited by controls. These results suggest that, since the double lesion produces a conditioned bradycardia similar to that of the controls, the increase in the amplitude of this response observed after early cerebellar removal may depend on the mPFC which, in the absence of specific cerebellar circuits, is unable to produce a properly calibrated HR conditioned response
Long lasting musical training modifies language processing: a Dichotic Fused Word Test study
Full text linkMusical training modifies neural areas associated with both music and language and enhances speech perception and discrimination by engaging the right hemisphere regions classically associated with music processing. On these bases we hypothesized that participants with extended musical training could have reduced left-hemisphere dominance for speech. In order to verify this hypothesis, two groups of right-handed individuals, one with long-term musical training and one with no musical training, participated to a Dichotic Fused Word Test consisting in the simultaneous presentation of different pairs of rhyming words and pseudo-words, one to the left ear and one to the right one. Participants typically show a greater number of reports of the right ear input than of the left one. This effect, called right ear advantage (REA), reflects left-hemisphere dominance for speech processing. In our study, we expected that musicians had a reduced dichotic listening REA for linguistic stimuli. The main result of this study was the attenuation, and in some cases the complete suppression, of the dichotic effect in musicians, since most of them perceived both words, simultaneously. This finding suggests that both hemispheres may have similar verbal competence and contribute to speech processing in parallel. This contrasts with the normal brain organization in which hemispheres cooperate but are engaged in different analysis of speech. The "two words" perception also extended to pseudo-words. Thus, musical training, by shaping the language circuits, could produce the enhancement of bilateral processing of stimuli with linguistic characteristics (i.e. phonetics) independently of semantics
Classical heart rate conditioning and affective behavior: the role of cerebellar vermis.
No full textThe involvement of the cerebellar vermis in the control of affective behaviors and in the coordination of fear-related somatic and autonomic conditioned responses is reviewed in this paper. In particular, the review focuses on the role of the midline cerebellum (vermis) on the acquisition and/or expression of classically conditioned bradycardia in the rabbit. The results of both lesioning and electrophysiological experiments indicate that the cortex of lobule III through VII is important, although not essential, in the acquisition and retention of this response, but it is not the site of its memory trace. The time course of the development of the conditioned bradycardia in neonatal rabbits is also described. The results obtained are consistent with the possibility that the expression of conditioned bradycardia may depend on the complete maturation of cerebellum. Moreover, preliminary data on the effects of the ablation of cerebellar vermis, performed at early stages of development, on the characteristics of conditioned bradycardia showed by adult rabbits are presented. These results indicate that cerebellar vermis is essential for the correct maturation of the response and that the timing of the lesion is critical for determining the characteristics of conditioned bradycardia in the adult
Role of the medial prefrontal cortex in the development of the conditioned bradycardia in cerebellar vermis lesioned rabbits
No full textQuestionnaires do not discriminate motor imagery ability of people with different motor expertise
Full text linkQuestionnaires are presented as reliable measure of motor imagery (MI), i.e. the ability to mentally simulate a movement in an internal perspective. Although there is some evidence that MI is domain-specific (i.e., i.e., higher scores for motor imagery may be generated by people with extensive real-world experience and practice), MI studies have typically employed fixed and generic movements as items. Thus, we investigated the content validity of the movement items of the Vividness of Movement Imagery Questionnaire-2 (VMIQ-2). Sixty participants were divided in groups of athletes (competitive and not-competitive, with an extensive motor experience) and not-athletes (with a reduced motor experience) and analysed by means of a mixed factorial MANOVA. The three MI modalities, external visual, internal visual and kinesthetic imagery, did not result in significantly different scores between the groups. We recommend caution in using MI generic questionnaires in studies that compare people with different motor experiences. Moreover, we suggest that the structure of the questionnaires should be redesigned, in order to make them adaptable to the specific needs of professionals and researchers.Los cuestionarios han sido considerados como medidas fiables y válidas de imaginación motora (IM), entendida como la habilidad de un sujeto de simular mentalmente un movimiento desde su perspectiva interna. Aunque hay evidencia que la IM es específica de dominio (e.g. puntuaciones más altas de IM se generan en aquello sujetos con mayor práctica y experiencia en el mundo real). En este estudio, hemos investigado la validez de contenido para los items de movimientos de la escala VMIQ-2 ("Vividness of Movement Imagery Questionnaire-2"). Sesenta participantes fueron divididos en 2 grupos mediante MANOVA factorial mixto: un grupo de "atletas" (con mayor experiencia motora, participación competitiva y no competitiva) y un grupo de "no-atletas" (con una experiencia motora reducida). Como esperábamos, los grupos no difirieron en ninguna de las puntuaciones de las tres modalidades de la IM (visual externa, visual interna y cinestésico). Por ello, recomendamos ser cuidadosos en la utilización e interpretación de los cuestionarios de IM en estudios que comparan personas con distintas habilidades motoras. Además, la estructura de los cuestionarios probablemente deba volve a diseñarse para hacerlos adaptables a las necesidades específicas de los profesionales e investigadores
Hypnotizability as an adaptive trait
No full textThis paper reviews our studies on the hypnotizability/hypnosis-related modulation of the mind-body connection during relaxation and mental stress, considered as the extremes of the wakefulness cognitive-autonomic arousal. The concept of relaxation is discussed according to the observation that similar self-reports of relaxation and autonomic states may correspond to different EEG patterns in low (Lows) and highly hypnotizable subjects (Highs). Results obtained during mental stress are discussed in the light of a possible adaptive role of hypnotic susceptibility as a natural protection against cardiovascular hazard; in fact, only Highs can actively suppress the cardiovascular responses evoked by a moderate mental stress. All together, findings show that the body can differentially act to similarly experienced relaxation and mental stress and suggest for hypnotizable individuals an evolutionary advantage
Hypnotizability as an adaptive trait
No full textThis paper reviews our studies on the hypnotizability/hypnosis-related modulation of the mind-body connection during relaxation and mental stress, considered as the extremes of the wakefulness cognitive-autonomic arousal. The concept of relaxation is discussed according to the observation that similar self-reports of relaxation and autonomic states may correspond to different EEG patterns in low (Lows) and highly hypnotizable subjects (Highs). Results obtained during mental stress are discussed in the light of a possible adaptive role of hypnotic susceptibility as a natural protection against cardiovascular hazard; in fact, only Highs can actively suppress the cardiovascular responses evoked by a moderate mental stress. All together, findings show that the body can differentially act similarly experienced relaxation and mental stress and suggest for hypnotizable individuals an evolutionary advantage
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