摘要:

ABSTRACTThe lateral scalp distribution of the early negative selective‐attention effect on auditory eventrelated potentials (ERPs) was compared to the distribution of the midline‐negative N1 component inverting in polarity at the scalp area below the Sylvian fissure. No such polarity inversion was observed for the selective‐attention effect at the N1 latency. This result supports the proposal that another component, the processing negativity (PN), overlaps (summates to) the exogenous N1 in the ERPs to attended stimuli. A subsequent experiment demonstrated that the mismatch negativity (MMN: peaking at 150–200 ms), an ERP component automatically elicited by deviant stimuli presented among homogenous repetitive stimuli, had opposite polarities above and below the Sylvian fissure. Thus, the MMN at least partly emanates from a cerebral generator which considerably overlaps that of the N1. The results are discussed in terms of separability of the brain mechanisms involved in the voluntary and involuntary processing of auditory stimuli reflected by the PN and MMN, respe

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1986.tb00680.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

ABSTRACTThis study of the maturation of prestimulation‐induced modulation of startle in 3 to 8 year old children and adults demonstrated significant effects of age on both startle magnitude and onset latency. Startle was evoked by 104dB(SPL) 50‐ms bursts of white noise, and the amplitude and onset latency of the blink reflex were measured after integration of the obicularis oculi EMG. Prestimulation with 75dB 1000 Hz tones resulted in severe inhibition of both amplitude and latency in adults when 20‐ms tones preceded the startling stimuli by 120 ms or 250 ms. Following sustained prestimulation for 2000 ms, the adults showed modest nonsignificant response facilitation. Eight‐year‐old children showed mature inhibitory and facilitatory startle amplitude modulation, but significantly less inhibition and more facilitation of onset latency compared to adults. Preschool children showed significantly less amplitude and latency inhibition and more facilitation than 8‐year‐olds and adults. In response to prestimulation 120 ms before startling stimuli, the preschool children actually showed latency facilitation. Modulation of startle by prestimulation is mediated by brainstem neuronal networks. These findings suggest that brainstem mechanisms which mediate startle response modulation undergo development during early childhood and do not mature until about 8

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1986.tb00681.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

ABSTRACTThe amplitude and probability of periorbital EMG responses were assessed for a variety of stimuli. In Experiment 1, 50‐ms duration broadband noise (20–20K Hz) and tones (1000 Hz), at 95 and 100 dB(A), with rise/fall times of 2.5, 10, and 25 ms, were presented. Noise stimuli were more effective than tones for both response amplitude and probability. Stimulus intensity affected both measures for tones, but only response amplitude for noise. Increasing stimulus rise/fall time had no significant effect for noise, but resulted in lower probability for tones. In Experiment 2, 50‐ms duration 1000 Hz tones, at 98 and 102 dB(A), with rise/fall times of 1, 2.5, 5, and 10 ms were presented. Response amplitude was not affected by rise/fall time changes, but increasing rise/fall time from 5 to 10 ms resulted in lower probability. These data show that the startle response can reflect manipulations of stimulus bandwidth, intensity, and rise/fall time, and that startle amplitude and probability reflect these manipulations in different ways. The two response measures may indicate the activity of partially independent underlying mechanisms, with a startle “trigger’ determining response probability and a startle “amplifier’ determining response amplitude for suprathre

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1986.tb00682.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1986.tb00683.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

ABSTRACTTwo experiments were designed to examine the effects of cognitive set acquired during problem solving upon the orienting skin conductance response (SCR) to a tone and its omission. Forty‐two female college students were instructed to press a key when they had found out the rule set up between the presentation of a tone and a particular digit associated with the tone.In Experiment 1, the tones were presented at every third ‘0’position, at first. After this rule was discovered, in the first group, the tone‐presentation was altered to the every third ‘7’position (Tone 0–7 Group: n=7). In the second group, the tones were not further presented after the rule was discovered (Tone 0‐No Tone Group: n=9). In the third group, the tones were continuously presented even after the subjects had found the rule (Tone 0–0 Group: n=9). Then, in the Tone 0–7 and Tone 0–0 Groups one no‐tone trial was given. The results showed that the change of tone‐rule in the Tone 0–7 Group and the tone‐omission did not evoke an orienting response. In Experiment 2, the instructions were improved so that the subjects would maintain a cognitive set to detect a possible future change in the rule. Two groups, the Tone 0–7 (n=8) and Tone 0–0 (n=9) Groups, underwent the same procedure as in Experiment 1. It was shown that the change of tone‐rule in the Tone 0–7 Group and the tone‐omission in the Tone

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1986.tb00684.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1986.tb00685.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

ABSTRACTThe present study measured somatic muscle, cardiovascular, and endocrine responses to an unsignalled, rewarded reaction time task and examined the relative contributions of heart rate reactivity and Type A behavior in accounting for variability in response to the task. Task responses were characterized by significant changes in muscle tension, heart rate, blood pressure, cardiac output, and plasma norepinephrine concentration. Subjects shown to be high heart rate reactors during an independent cold pressor test were found to produce the greatest changes in heart rate, systolic and diastolic blood pressures, ventricular ejection time, cardiac output, and rate‐pressure product during the reaction time task. In contrast, Type As did not respond differently from Type Bs. The results indicate that heart rate reactivity is a relatively stable trait which generalizes from cold pressor to a nonaversive task and which accounts for much of the between‐subject variability in cardiovascular respo

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1986.tb00686.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1986.tb00687.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

ABSTRACTThe present experiment investigates whether there are sex differences in physiological reactions to real life stress and whether these reactions are differentially related to psychological variables in males and females. In 29 male and 23 female students physiological measurements were taken on the day of an examination and on a normal routine day. Behavioral characteristics were measured using questionnaires. Serum cholesterol level, systolic blood pressure, and heart rate were found to be higher on the examination day. These reactions did not differ between the sexes. Males showed a larger increase of urine‐adrenaline excretion than did females. In males, cholesterol level and response were related to achievement motivation. Ambulatory monitored HR during the exam correlated with state anxiety and state depression in females, but not in males. The analysis of sex specific expression of behavioral traits in physiological parameters, including the CHD risk factors, is of potential value for a better understanding of mechanisms mediating between behavior and CHD ris

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1986.tb00688.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1986.tb00689.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY