摘要:

ABSTRACTTwelve subjects were run in a paradigm designed to compare event‐related brain potentials (ERPs) elicited by infrequent pitch‐deviant and time‐deviant tones under different attentional conditions. Tones with a pitch of 500 Hz or 1000 Hz were presented at regular interstimulus intervals of 800 ms. Changes in pitch or a shortening of interstimulus interval to 400 ms each occurred with 10% probability. Three different tasks (reading or reaction time to pitch or to timing deviances) were assigned on separate runs.N150 to deviant tones was not influenced by task. Its amplitude, peak latency, and frontally maximum distribution did not differ between pitch and timing deviance, but to pitch deviance it had an earlier onset. P350 amplitude to both types of deviant tones was larger than to standard tones when subjects pressed to time‐deviant tones; only P350 to pitch‐deviant tones was larger than to standards when subjects pressed to pitch‐deviant tones. P350 latency was longer to timing deviance regardless of task.Our results support the view that negativities generated by mismatches in expected timing and pitch are qualitatively the same. ERP differences between these two types of deviance were probably due to differences in stimulus salience or discr

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1988.tb01238.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

ABSTRACTFourteen subjects were run in paradigms designed to explore event‐related brain potentials (ERPs) elicited by breaks in alternations in pitch or interstimulus interval. In the Pitch paradigm, tones of 500 Hz or 1000 Hz were presented in alternation at regular interstimulus intervals of 800 ms. In the Rhythm paradigm, a single tone, either 500 Hz or 1000 Hz, was presented at interstimulus intervals alternating between 400 ms and 800 ms. Breaks in the Pitch paradigm consisted of a single repetition of a pitch, and in the Rhythm paradigm of a single repetition of the 400‐ms interstimulus interval. Breaks occurred with a 10% probability in both cases. Subjects read while stimuli were being presented.A N210 wave of about 3.5 μV was elicited by breaks in pitch pattern but not by breaks in rhythm. That it was largest (most negative) frontally suggests that it was a type of mismatch negativity. Analysis of waveforms constructed by subtracting ERPs to standards from ERPs to breaks confirmed these results. Thus we conclude that the system triggering mismatch negativity can encode the temporal ordering of pit

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1988.tb01239.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1988.tb01240.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

ABSTRACTThe present study had two objectives: to examine the influence of parental history of hypertension on cardiovascular responses during behavioral stress in middle‐aged men and women; and to study the impact of parental history of myocardial infarction on stress responses. Participants were separated into four groups: no parental history of cardiovascular disease; parental history of hypertension only; parental history of myocardial infarction only; or parental history of both hypertension and myocardial infarction. Heart rate and blood pressure were monitored at rest and during serial subtraction, mirror image tracing, and isometric handgrip. Analyses of residualized difference scores showed that like younger, male offspring of hypertensives, middle‐aged men and women with a parental history of hypertension exhibited exaggerated diastolic blood pressure responses during all stressors. Men with a parental history of myocardial infarction, with or without a parental history of hypertension, exhibited exaggerated systolic blood pressure responses during all stressors. These data are the first to show that family history of hypertension influences middle‐aged men's and women's stress responses, and that family history of myocardial infarction influences men's stress responses. Results suggest the importance of parental history of cardiovascular diseases in understanding acute psychophysiological responses of middle‐aged

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1988.tb01241.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1988.tb01242.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

ABSTRACTHeart rate offset responses to visual stimuli were studied in infants tested cross‐sectionally at 14, 20, and 26 weeks of age. In Experiments 1 and 2, offset responses were measured in each infant following visual stimuli presented with three procedures. The fixed interval method consisted of stimulus presentations of 7 s in duration. The infant control method consisted of stimulus presentations which were terminated when the infant looked away from them. The interrupted stimulus method consisted of stimulus presentations which were terminated when the infant looked away toward an interrupting, secondary stimulus. In Experiment 3 these procedures were compared with two procedures in which stimulus termination occurred at the point of heart rate deceleration or the return of heart rate toward prestimulus level. The stimuli in Experiment 1 were checkerboard patterns, in Experiment 2 were complex and varying stimuli, and in Experiment 3 were either TV stimuli or an overhead light.The offset responses were similar for the fixed interval and infant control methods, and consisted of brief heart rate decelerations. The magnitude of the heart rate response was generally small (1.5 to 2 bpm), with the largest heart rate response being 4 bpm. The pre‐offset heart rate response was similar for the infant control and interrupted stimulus and heart rate acceleration trials, with heart rate showing a return to prestimulus levels immediately preceding subject‐controlled fixation termination. Infants with high levels of respiratory sinus arrhythmia (RSA) measured during a 5‐min baseline showed larger heart rate offset responses than did low RSA infants. These results call into question the interpretation of heart rate offset responses in the context of Sokolov's model of the orienting response. However, the offset paradigm is useful in the study of subject‐controlled attention

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1988.tb01243.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1988.tb01244.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

ABSTRACTThis study investigated the effects of methylphenidate in a memory scanning task with two levels of high cognitive load (memory set sizes 2 and 4 presented in displays of size 4) and two response requirements (simple mapping or rotation). Twenty young adults were tested under placebo and methylphenidate (0.3 mg/Kg) in a double‐blind protocol. As expected, memory load increased misses, false alarms, confusions, and failures to respond by the deadline. In turn, the rotation requirement increased confusions and nonresponses. Reaction time (RT) was slowed by both factors. P3b latency also was increased by memory load and, to some extent, by the rotation requirement. These results are consistent with the proposition that P3b latency reflects largely evaluation, rather than response processes.Misses and reaction time were decreased in response to targets presented in the center vs. the periphery of the display. Confusions, however, showed the opposite trend. The display position did not affect P3b latency. These results can be explained by assuming that the subject was focusing on the center of the display and that accuracy diminished when stimuli were presented toward the periphery of the display.The stimulant challenge speeded up reaction times overall and specifically reduced the slowing effect of rotation. However, P3b latency was not affected by methylphenidate, so that the speeding of reaction time by the stimulant can be attributed to post‐evaluation proces

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1988.tb01245.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1988.tb01246.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

ABSTRACTCardiac responses to non‐signal stimuli and to signal stimuli in a vigilance task were examined in children born with congenital heart defects (CHD), and in normal and attention deficit disordered (ADD) subjects. Overall task performance was lower in subjects with heart defects and in the ADD group. Cardiac measures revealed that normal children displayed significantly larger heart rate deceleration to the target stimuli than did either of the clinical groups. Moreover, although no group differences were observed in the cardiac response to non‐signal auditory stimuli, exaggerated heart rate deceleration was observed to vibrotactile stimuli in both the clinical groups. Regression analyses revealed that the magnitude of the cardiac response to somatosensory stimuli was predictive of task performance (both within and between subject groups), with larger responses associated with higher error rates and lower perceptual sensitivity. Results were suggestive of a predictive relationship between somatosensory reactivity and neuropsychological maturat

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1988.tb01247.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY