ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1992.tb02013.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1992.tb02014.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1992.tb02015.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1992.tb02016.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

ABSTRACTThe effects of food intake on the P300 (P3) component of the event‐related brain potential (ERP) were assessed in two studies. Experiment 1 compared 24 subjects who had not eaten within 6 hours of testing with 24 subjects who had consumed food within 3 hours of testing. P3 target stimulus amplitude was reduced significantly for the subjects who had not eaten relative to those who had eaten, whereas peak P3 latency was only moderately affected by the recency of food consumption over task conditions. In Experiment 2, P3 measurements, memory performance in a word recall task, and blood glucose levels were obtained from 24 subjects at three different times: 1) after a 14‐hour fast, 2) 5 min after consuming lunch, and 3) 30 min after consuming lunch. P3 target stimulus amplitude increased initially after food intake and decreased slightly at the third measurement time, while peak P3 latency became somewhat shorter immediately after food intake but then returned to baseline. Recall for recently presented items mimicked the P3 amplitude changes, whereas blood glucose levels increased monotonically across food conditions. The results from both studies suggest that: 1) target stimulus P3 amplitude is affected by the recency of food intake; 2) food‐related P3 amplitude changes appear related to memory function; and 3) subjects should eat within several hours before ERPs are acquired to ensure that P3 component measurements reflect values indicative of normal bodily functi

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1992.tb02017.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1992.tb02018.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

ABSTRACTTo determine how individual differences stemming from activity preference, previous food intake, and time‐of‐day affect the P300 or P3 event‐related brain potential (ERP), subject groups who varied orthogonally on these factors were compared using a simple auditory discrimination task to elicit the ERPs. Amplitude of the P3 component for morning‐preferring subjects who had eaten recently was relatively large for both the morning and evening measurement time groups. P3 amplitude for the morning‐preferring subjects who had not eaten recently was large for those measured in the morning and relatively small for those subjects measured in the evening. For evening‐preferring subjects who had eaten recently, P3 amplitude was again relatively large for both the morning and evening measurement time groups. Evening‐preferring subjects who had not eaten recently produced very small P3 components for those measured in the morning compared to the large components produced by those subjects measured in the evening. P3 latency tended to be longer for all subjects who had not eaten recently compared to those who had. The results suggest that the P3 component is sensitive to physiological and psychological changes originating from individual differences related to bodily state, which perhaps stems from individual differences in

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1992.tb02019.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

ABSTRACTHeart rate and respiration rate were recorded with a portable data recording system before and during a parachute jump in 36 male sport parachutists with differing degrees of experience. The recordings were analyzed at 12 psychologically relevant points in time along with the subjective ratings of physical arousal. Novice parachutists showed a higher degree of self‐rated arousal during jumps. However, the two groups displayed nearly parallel curves for heart and respiration rates, differing significantly from each other only in the level of their respective heart rates. Furthermore, experienced jumpers seem to be better informed about their state of physiological arousal during the jump than are novice jumpers. These results do not confirm the proposed anxiety inhibition process, postulated by Epstein (1967

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1992.tb02020.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

ABSTRACTThis study examined the effects of memory search and related processes on both time and frequency domain components of electroencephalographic activity. More specifically, we were interested in the relationship between EEG and event‐related potential (ERP) components as a function of memory load and response type. Subjects performed a semantic memory search task in which they matched word probes to category labels. Consisten with previous studies, reaction time increased and accuracy decreased with increasing memory loads. A negative component of the ERP (N400) was found to reflect semantic mismatch: N400s were larger for the nontargets than for the targets. Two ERP components were found to be reciprocally related to memory load. P300 decreased and Negative Slow Wave increased in amplitude with increases in the size of the memory set. These two ERP components were reflected by different components in a Principal Components Analysis. The power in the theta band (5–7 Hz) also increased as a function of memory load and appears to be functionally and topographically related to the Negative Slow Wave in the ERP. It is argued that both measures are jointly determined and reflect the difficulty of the conceptual operations during memory sea

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1992.tb02021.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

ABSTRACTHeart rate rhythms have been demonstrated to parallel specific psychological processes. Efficient experimental control of the amplitude of these rhythms would allow evaluation of bidirectional psychophysiological hypotheses. This experiment was performed to examine the specificity of the heart rate rhythm response to oscillatory head‐up tilt. Seventy‐one adults (36 male, 35 female) aged 18–30 were positioned on a tilt‐table and oscillated at 0.08 Hz with a maximum tilt angle of +210for a 10‐min period. Heart period, heart period variability at 0.08 Hz (i.e., Traube‐Hering‐Mayer (THM) variance), and respiratory sinus arrhythmia (quantified using vagal tone, V̂) were measured. For a subset of 21 subjects, continuous measures were derived to examine the response to onset of oscillatory tilt. Respiratory activity was also measured in these subjects. There was a significant increase in the amplitude of the THM variance during tilt stimulation. Tilt did not significantly change heart period, V̂, or respiration frequency. Following cessation of tilt, THM variance returned to baseline levels, heart period lengthened for males, and V̂ increased for both sexes. Subjects with higher amplitude baseline V̂ were characterized by more rapid THM variance response to tilt. Results suggest that parasympathetic tone moderates the THM variance increase elicited by low‐frequen

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1992.tb02022.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY