摘要:

ABSTRACTSrain‐gauge plethysmography was used to study phasic forearm blood flow (FBF) responding, which has been presumed to occur in human subjects prior to voluntary muscular contraction. In a two‐group design, 10 subjects performed a 7‐s, fixed‐foreperiod, reaction‐time (RT) task in which static handgrip was the required RT response; 10 additional subjects in a High Incentive (HI) condition performed a more stressful delayed avoidance task. Bilateral FBF and HR were computer‐sampled over the preparatory interval (PI) and transformed into second‐by‐second measures. Mean FBF estimates were also obtained by averaging over the entire PI. HI subjects were found to manifest significantly greater mean FBF prior tro motor responding than did subjects performing the nonstressful RT taks. Such preparatory FBF responding was task‐specific, occurring only in the Arm to be performing the signalled RT response. Furthermore, this task‐specific, phasic increase in averaged mean FBF was observed to occur in subjects' left and right arms. Trend analysis and visual inspection of second‐by‐second FBF waveforms demonstrated a gradual decline in flow rate over the course of the preparatory interval under all experimental conditions. HR responding manifested the characteristic triphasic waveforms, with higher heart rate and augmentation of acceleratory and terminal deceleratory components exhibited by the HI group. the findings suggest that human phasic FBF responding can be influenced by motoric and motivational factors as well as by demands for

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1984.tb00213.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1984.tb00214.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

ABSTRACTBilateral electrodermal recordings are often used in psychophysiological research as a measure of functional hemispheric asymmetry. Although significant differences between left and right hand recordings are reported in the literature, the obtained differences are often in different directions. The purpose of the present paper was to review empirical evidence related to the issue of bilateral electrodermal recordings in research on hemispheric asymmetry. Special reference is made to the current controversy concerning contralateral inhibition vs. excitation or facilitation as the underlying mechanism for reported differences in performance of typical hemisphere‐specific tasks. After reviewing the evidence, which is contradictory concerning several of the more critical parameters, the conclusion is that bilateral electrodermal recordings have not been unambiguously related to hemispheric asymmetry. However, when asymmetry between the hands is clearly demonstrated, this reflects an asymmetry in the functioning of the cerebral hemisphere

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1984.tb00215.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

ABSTRACTAuditory event‐related potentials (ERPs) were recorded from subjects who attended selectively to a sequence of tones of one frequency and ignored a comparable sequence of tones having a different frequency and spatial origin. In one condition the tones consisted of randomized sequences of brief tone pips while in a second condition the tones were brief increments in intensity (pedestals) of continuous tones at the two frequencies. The tone pips and pedestals were delivered at comparable interstimulus intervals (ISIs), which were short (250–550 ms) in some runs and long (1250–2750 ms) in others. For both classes of stimuli, the subject's task was to detect occasional “target” tones of a slightly shorter duration than the more frequent “standard” tones. Stimuli of the attended frequency elicited a broad negative ERP component (Nd) relative to the unattended tone ERPs. The Nd wave had a considerably shorter onset latency and was smaller in overall amplitude at the faster rate of stimulation. However, the Nd wave did not differ in latency or amplitude between the tone pip and pedestal conditions at corresponding ISIs, suggesting that a high rate of information delivery is a more important factor in accelerating Nd onset than is the continuous reinforcement of the sensory cues that define the two cla

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1984.tb00216.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

ABSTRACTThis study examined the effects of restricting sleep to the first or second half of the night on the composition of sleep and on performance. Eight young women who regularly slept for 8–8.5 hrs a night had their sleep restricted to the first or second half of the night for two consecutive nights. Performance of a 20‐min unprepared simple reaction time task was measured at fixed times of day for the two restricted sleep conditions and for a full night sleep control condition. Restricting sleep to the second half of the night produced higher amounts of REM sleep and Stage 4 sleep and lower amounts of Stage 2 sleep compared to restricting sleep to the first half of the night. Both restricted sleep conditions impaired performance relative to the full night sleep control, and performance was worse after two nights of restricted sleep than after one night of restricted sleep. The results show that the effects of a restricted sleep regime on the composition of sleep are partly a function of the time of night to which sleep is restricted. It is suggested that the performance deficits are due to loss of sleep per se rather than due to any change in the composition of sl

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1984.tb00217.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

ABSTRACTRichards and Rader (1983) argue in their recentPsychophysiologypaper that crawling experience plays no significant role in the development of visual cliff performance, and also that “fear” is not related to the development of the avoidance of heights. It is our contention that these conclusions rest upon oversimplified assumptions about the nature of fear and its determinants on the visual cliff. A very different set of inferences emerge from an alternative conceptualization of the problem. In contrast to Richards and Rader, we argue that heart rate cannot be simply equated with fear but rather represents one of many loosely correlated indices. Evidence is presented to show that behavioral and cardiac responses converge to demonstrate fear of heights by locomotor infants. It is further argued that the role of crawling experience is not given an adequate test by Richards and Rader. The theoretically important test involves a comparison between locomotor and prelocomotor infants. Data from such comparisons are reviewed and found to support self‐produced locomotion as an important predictor of visual cliff perfor

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1984.tb00218.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

ABSTRACTSeveral authors have advanced the hypothesis that the right cerebral hemisphere predominates during REM sleep. This hypothesis was tested by giving a newly‐devised unilateral tactile recognition test to 16 right‐handed male subjects during waking and upon awakenings from REM and NREM sleep.A two‐way analysis of variance revealed both a main effect for hand (the left hand being superior to the right) and a condition (waking‐REM‐NREM) X hand interaction. Consistent with the hypothesis of right‐hemisphere activation during REM, left‐hand superiority upon awakenings from REM was greater than that during waking; in the NREM condition, no between‐hand difference was observed. The latter result, as well as previous findings by Gordon, Frooman, and Lavie (1982), seems to point to the presence of left‐hemisphere activation during NREM and, more generally, to the link between hemispheric functional alternation and t

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1984.tb00219.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1984.tb00220.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

ABSTRACTMost studies which have tested the hypothesis of autonomic hyporeactivity in antisocial groups using skin conductance orienting response (SCOR) amplitudes have failed to confirm this prediction. However, frequency measures may represent more stable and complete indices of responsivity than amplitude measures and, therefore, provide a better test of an antisociality‐hyporeactive relationship. This possibility was tested by relating electrodermal responding‐nonresponding to a series of 65dB tones in 101 15‐yr‐old males to measures of antisocial behaviour and undersocialization. While SCOR amplitudes were unrelated to antisociality, frequency of response and incidence of nonre‐sponding were significantly related in the predicted direction. A second analysis demonstrated antisocial nonresponders to be characterised by schizoid tendencies, but not by sensation‐seeking. These data indicate that equating nonresponding with antisociality and interpreting such a relationship in motivational/arousal terms may be over‐simplistic, and that it may be specifically a schizoid subsection of antisocials who are characterised by nonresponding. It is hypothesised that the frequently cited link between antisociality and psychosis‐proneness may be underpinned by a disturbance of sustained attention as indexed b

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1984.tb00221.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1984.tb00222.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY