摘要:

AbstractThe vagus, the 10th cranial nerve, contains pathways that contribute to the regulation of the internal viscera, including the heart. Vagal efferent fibers do not originate in a common brainstem structure. The Polyvagal Theory is introduced to explain the different functions of the two primary medullary source nuclei of the vagus: the nucleus ambiguus (NA) and the dorsal motor nucleus (DMNX). Although vagal pathways from both nuclei terminate on the sinoatrial node, it is argued that the fibers originating in NA are uniquely responsible for respiratory sinus arrhythmia (RSA). Divergent shifts in RSA and heart rate are explained by independent actions of DMNX and NA. The theory emphasizes a phylogenetic perspective and speculates that mammalian, but not reptilian, brainstem organization is characterized by a ventral vagal complex (including NA) related to processes associated with attention, motion, emotion, and communication. Various clinical disorders, such as sudden infant death syndrome and asthma, may be related to the competition between DMNX and NA.

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1995.tb01213.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

AbstractWe examined the attentional sensitivity of the frequency‐change mismatch negativity (MMN). Subjects listened to a binaural mixture of a narrative and a series of tone bursts that included 1200‐Hz standards and two deviants (1000 and 1400 Hz). In the attend‐tones condition, subjects responded to one deviant and ignored the narrative. In the attend‐words condition, subjects responded to target words in the narrative and ignored the tones. Event‐related potentials (ERPs) were recorded for the tones, and differences waves (deviant ERPs minus standard ERPs) were computed. Two negative peaks in the difference waves, DNI (100–180 ms) and DN2 (200–300 ms), overlapped the known scalp distribution and latency of the MMN. Mean DN1 and DN2 amplitudes were greater in the attend‐tones condition than in the attend‐words condition. These data suggest that the frequency‐change MMN is modulated by nonspatial shifts of

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1995.tb01214.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

AbstractIn this study, we examined autonomic influences on pulse transit time measured from the R‐wave of the electrocardiogram (R‐PTT). Six subjects received three doses each of isoproterenol and atropine. Isoproterenol produced a significant linear decrease in R‐PTT, a significant linear increase in heart rate (HR), and a significant linear decrease in diastolic blood pressure (DBP). Atropine produced a significant linear decrease in R‐PTT and significant linear increases in HR and DBP. The R‐PTT shortening effect of isoproterenol may reflect positive inotropic effects of beta‐ sympathetic myocardial stimulation. The R‐PTT shortening effect of atropine may reflect reduction of parasympathetic inhibition of ventricular myocardial activity. However, possible vascular contributions to these effects remain to be determined. Nonetheless, the results encourage further examination of R‐PTT in research concerning autonomic regulation of cardiova

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1995.tb01215.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

AbstractIn the present study, we compared the performance of normal subjects in three age groups and of medicated Parkinson's disease patients on auditory selective attention processes. Two tone sequences were dichotically presented. Subjects responded to deviant tones in the attended location. Event‐related potentials (ERPs) were recorded from nine scalp electrodes. The old group showed significant decline in hit rate, increase in N1 amplitude, and reduction in P3a, P3b, target negativity, and mismatch negativity amplitude. The amplitude and duration of late Nd increased with age, reflecting modulation of both attended and unattended standard ERPs. Although the middle group showed a similar pattern of ERP changes, the effects were generally nonsignificant. The Parkinson's disease group showed little further disruption of behavioral or ERP measures. However, Parkinson's disease affected late Nd in the direction opposite of that of aging, reflecting differential modulation of unattended standard positivit

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1995.tb01216.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

AbstractIn this study, I examined emotional modulation of the eyeblink, skin conductance, and cardiac responses to an acoustic startle (103 dB[A] white noise) probe. Twenty‐five female and 17 male undergraduates imagined pleasant, neutral, and fearful situations in a tone‐cued imagery procedure. Both the eyeblink and skin conductance responses to startle probes were potentiated (larger magnitude, shorter latency) during fear as compared with neutral and pleasant imagery. The amount of emotional modulation in these two response systems was significantly correlated both between and within subjects. The startle probe interrupted ongoing cardiac deceleration during the imagery task, but this interruption was not related to the emotional content of imag

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1995.tb01217.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

AbstractThe aim of the present study was to quantitatively investigate the role of information processing in conditioning using stimuli with varying amounts of information content. A letter reproduction task varying in complexity served as the unconditioned stimulus. In the first experiment, we tested the indicator function of electrodermal and car‐diovascular variables. The amount of information processing resources required emerged most clearly in electrodermal reactions (EDRs), showing an increase with increasing stimulus information content. A second experiment was performed using the same design to confirm the role of processing resources allocation during conditioning by means of an independent indicator. A reaction time task was introduced as a measure of information processing resources utilized. The results paralled the dependence of EDRs on stimulus information content, as was found in the first experimen

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1995.tb01218.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

AbstractThe human startle reflex is reliably modulated by the affective valence of foreground pictures, with larger reflexes elicited when viewing unpleasant relative to pleasant scenes. If this modulation is due to priming of the defensive startle reflex by an aversive foreground, a different pattern should occur for a reflex that is not inherently defensive in nature. In the current study, affective modulation was investigated using the spinal tendinous (T) reflex, which is well documented as sensitive to differences in arousal and is involved in actions that are both appetitively and defensively motivated. As such, T reflexes elicited during unpleasant pictures were not expected to be augmented relative to those elicited in the context of pleasant pictures. Results showed that T reflexes were facilitated during processing of arousing stimuli – either pleasant or unpleasant relative to low‐arousal neutral materials. These effects of emotional stimuli on T‐reflex amplitude are consistent with the hypothesis that motivational priming underlies affective reflex modul

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1995.tb01219.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

AbstractBrain event‐related potentials (ERPs) to probe tones in a dichotic complex tone test were recorded from right‐handed depressed patients (n= 44) and normal subjects (n= 19) at homologous sites over left and right hemispheres (F3, F4; C3, C4; P3, P4; O1, O2). There were no differences between groups in N1 or P2 amplitude, but patients had smaller P3 amplitude than did normal subjects. Depressed patients failed to show either the left ear advantage or behavior‐related hemispheric asymmetry of P3 seen for normal subjects. Depressed patients also showed less differences in hemispheric asymmetry betweensameanddifferentjudgments. These findings indicate that the abnormal behavioral asymmetry for dichotic pitch discrimination in depressed patients reflects a reduction in hemispheric asymmetry and is related to relatively late stages of cognitive proce

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1995.tb01220.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

AbstractTo isolate the anatomical locus of the neural activity most important for generating or modulating the scalp‐recorded N400 and P600 components elicited during continuous recognition memory tasks, intracranial event‐related potentials (ERPs) were recorded from medial and lateral aspects of the temporal, frontal, parietal, and occipital lobes in 25 patients undergoing stereoelectroencephalography for seizure localization. Large‐amplitude and polarity‐inverted ERPs were recorded from various temporal, frontal, and parietal structures, whereas the memory‐related ERP modulation assessed by the ERP repetition effect was present only in those brain areas that play the most important role in memory processing. These data suggest that the scalp‐recorded N400 and P600 components may represent the most readily observable aspect of synchronous activity occurring across widely distributed brain structures and neural systems underlying different cognitive mechanisms, which all contribute to some aspect of information processing during recogni

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1995.tb01221.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

AbstarctFifteen subjects participated in an experiment designed to assess the contingent negative variation (CNV) during the labeling of odors and shapes. Odors or shapes were presented (SI) and followed 3 s later by a lexical label (A, B, or C) (S2). In 75% of the trials, the S2 was the correct label for the odor or shape. In the remaining trials, the S2 was an incorrect label. Subjects' olfactory performance was correlated with both the CNV during in the S1/S2 interval and also the P300 following the S2 stimulus. The CNV over the left frontal area was significantly larger in the olfactory phase of the experiment. CNV activity also correlated with olfactory performance such that subjects with the largest odor‐related CNVs had the best olfactory performance. Although P300 differed as a function of label matches versus mismatches, no odor‐specific effects or correlations were fo

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1995.tb01222.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY