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1.
A. A. Cherninskii N. G. Piskorskaya I. G. Zima S. A. Krizhanovskii N. Ye. Makarchouk 《Neurophysiology》2010,42(1):63-69
We studied changes in human EEGs related to presentation of olfactory stimuli (smells of essential oils) and dependence of
such rearrangements on the level of extroversion/introversion typical of the tested subject. It was shown that this feature
of personality noticeably influences the pattern of odorant-induced changes in EEG. Persons with a predominance of introversion
were characterized by higher levels of nonspecific activation of the brain related to perception of olfactory stimuli, which
was manifested in a decrease in the power of low-frequency EEG components in the parietal, occipital, and temporal cerebral
cortices. The pattern of the rise in coherence level of high-frequency spectrum range oscillations directed toward caudal
leads is considered a manifestation of intensification of the intrinsic associative processes. In individuals with a predominance
of extroversion, we observed, on the whole, smaller levels of nonspecific cerebral activation upon the action of olfactory
stimulation. The fronto-parietal pattern of spatial EEG synchronization is indicative of the development of sensory-analytical
processes related to perception of external information. In general, our data agree with the interpretation of such a psychological
parameter as extroversion/introversion. 相似文献
2.
Topographic analysis of dimension estimates of EEG and filtered rhythms in epileptic patients with complex partial seizures 总被引:2,自引:0,他引:2
Nonlinear dynamic properties were analyzed on the EEG and filtered rhythms recorded from healthy subjects and epileptic patients
with complex partial seizures. Estimates of correlation dimensions of control EEG, interictal EEG and ictal EEG were calculated.
The values were demonstrated on topograms. The delta (0.5–4 Hz), theta (4–8 Hz), alpha (8–13 Hz), beta (13–30 Hz) and gamma
(30–40 Hz) components were obtained and considered as signals from the cortex. Corresponding surrogate data was produced.
Firstly, the influence of sampling parameters on the calculation was tested. The dimension estimates of the signals from the
frontal, temporal, parietal and occipital regions were computed and compared with the results of surrogate data. In the control
subjects, the estimates between the EEG and surrogate data did not differ (P > 0.05). The interictal EEG from the frontal region and occipital region, as well as its theta component from the frontal
region, and temporal region, showed obviously low dimensions (P < 0.01). The ictal EEG exhibited significantly low-dimension estimates across the scalp. All filtered rhythms from the temporal
region yielded lower results than those of the surrogate data (P < 0.01). The dimension estimates of the EEG and filtered components markedly changed when the neurological state varied.
For each neurological state, the dimension estimates were not uniform among the EEG and frequency components. The signal with
a different frequency range and in a different neurological state showed a different dimension estimate. Furthermore, the
theta and alpha components demonstrated the same estimates not only within each neurological state, but also among the different
states. These results indicate that the theta and alpha components may be caused by similar dynamic processes. We conclude
that the brain function underlying the ictal EEG has a simple mechanism. Several heterogeneous dynamic systems play important
roles in the generation of EEG.
Received: 10 December 1999 / Accepted in revised form: 8 May 2000 相似文献
3.
Verbal cues modulate hedonic perception of odors in 5-year-old children as well as in adults 总被引:1,自引:0,他引:1
The judgment of pleasantness/unpleasantness is the prominent reaction to the olfactory world. In human adults, the hedonic valence of odor perception is affected by various factors, among which is an individual's lexical knowledge about smells. The present study examined whether such top-down effects of lexical knowledge on hedonic judgment of olfactory input are similar in children (5-6 years) and adults (20-25 years). In both groups, the lexical knowledge was found to influence the perception of the least emotional (or most neutral) odors: the pleasantness of the smells of banana and mint was enhanced when participants were given the corresponding odor label before olfactory sensation. These results lend support to the notion that, during childhood, smells are not only encoded perceptually but that verbal encoding also steers contextual effects that may be prominent factors in the early memorization and categorization of odors. 相似文献
4.
Electroencephalograms (EEGs) were recorded in 19 standard derivations in 88 healthy subjects (students) in the state of rest
with eyes open and during memorization (learning) of verbal bilingual semantic pairs (the Latin and Russian languages) and
retrieval of information from memory (control). The estimates of EEG coherence in these states were compared for the following
frequency bands: θ (4–7 Hz), α1 (7–10 Hz), α2 (10–13 Hz), β1 (13–18 Hz), β2 (18–30 Hz), and γ (30–40 Hz). Compared to the state of rest, the decrease in coherence in the pairs of derivations from the
frontal and central cortical areas in all EEG frequency bands was the most pronounced for memorization, and the increase in
coherence in the interhemispheric derivation pairs of the parietal-occipital region in most of the frequency bands was the
most pronounced for retrieval. In addition, in the pairs formed by derivations from the parietal-occipital region with derivations
from the frontal and central regions, retrieval is also characterized by an increase in coherence in the β2 and γ bands along with its decrease in the low-frequency ranges. The dynamics of EEG coherence, when comparing the states
of memorization and retrieval, is more statistically significant in the interhemispheric and cross-hemispheric pairs of derivations
than in the intrahemispheric pairs. The revealed topographic specificity of the dynamics of EEG coherence owing to the change
of state is considered in terms of the notion on cognitive-specific forms of sustained goal-directed mental attention. 相似文献
5.
Independent component analysis (ICA) of 19-channel background EEG was performed in 111 patients with the early signs of depressive
disorders and in 526 healthy subjects. The power spectra of the independent components were compared in the depressive patients
and in healthy subjects at the eyes closed and eyes opened states. Statistically significant differences between the groups were detected in three frequency bands: θ (4–7.5 Hz), α
(7.5–14 Hz), and β (14–20 Hz). Increased θ and α activities in parietal and occipital derivations of depressive patients may
have been caused by a reduced cortical activity in the projection of these derivation. Diffuse enhancement of the β activity
may be correlated with anxiety symptoms that are pronounced in the clinical picture of depressive disorders at early stages
of the disease. ICA used to compare quantitative EEG parameters in different groups of patients and in healthy persons makes
it possible to localize the differences more accurately than the traditional analysis of EEG spectra. 相似文献
6.
V. A. Ponomarev O. V. Kropotova Yu. D. Kropotov Yu. I. Polyakov 《Human physiology》2000,26(3):251-257
Evoked desynchronization and synchronization of EEG in θ (4–7.5 Hz), α (7.5–14 Hz) and β (14–20 Hz) ranges were recorded by
19 electrodes in healthy volunteer adolescents and those with attention deficit hyperactivity syndrome in the modified GO/NO-GO
test. Two stimuli (high and low tone) were presented in pairs with 1 s intervals inside the pair and 1.5 s intervals between
the pairs. Test subjects had to push the button in response to presentation of a pair of high tones and to ignore other stimulus
combinations. The components of evoked EEG synchronization in α-θ range that were revealed in the frontocentral and temporoparietal
brain regions in connection with inhibition of action (inhibition of movements and making a decision to cancel sensory-motor
task performance) were statistically significantly lower in subjects with attention deficit hyperactivity disorder compared
with that in healthy subjects. 相似文献
7.
We studied correlations between the frequency of background impulse activity (BIA) of dopaminergic (DAergic) neurons of the
ventral tegmentum (VT) and spectral power (SP) of the frequency components of EEG samples recorded in awake cats. The EEG
was recorded monopolarly (electrodes were fixed in the cranial bones) from the frontal, occipital, and right and left temporal
regions of the cortex. In a great majority of the cases, the BIA frequency of VT DA-ergic neurons demonstrated significant
positive correlations with changes in the SPs of the alpha and beta EEG rhythms. The closest correlations of the spiking frequency
of DA-ergic cells with the SP of the alpha rhythm was observed in the occipital region, while those with the beta SP were
found in the frontal area. Correlations of the activity of DA-ergic neurons with the SPs of the alpha and beta rhythms in
the left temporal cortical zone were closer, as compared with those in the symmetrical right zone. Correlations of the SPs
of the delta, theta, and gamma EEG components with the discharge frequency of VT DA neurons were of opposite directions, and
in most cases such correlations did not reach the level of significance. The results of this study show that, in some cases,
specific EEG patterns can be considered indicators of the state of the cerebral VT DA-ergic system.
Neirofiziologiya/Neurophysiology, Vol. 40, No. 4, pp. 359–367, July–August, 2008. 相似文献
8.
The development of the resonance EEG responses of the left and right occipital areas was studied in right-handed men during
prolonged (12 or 120 s) rhythmic, photostimulation with the intensity of 0.7 J and frequencies of 6, 10, and 16 Hz. Analysis
of the EEG fine spectral structure was applied to compare the accumulated baseline EEG spectra and EEG spectra during photostimulation,
to observe the dynamics of the short-term spectra and to detect power changes in the EEG narrow spectral band sharply coincident
with the stimulation frequency. The more pronounced EEG responses to photostimulation were observed in subjects with the initially
low EEG baseline, α-rhythm. Two-minute flash trains produced a substantial increase in the EEG power within the stimulation
frequency with superposed oscillatory processes with different periods. These fluctuations are considered a reflection of
intricate interaction between the adaptive and resonance EEG responses to the presented intermittent stimulation. Under 12-s
stimulation the resonance EEG responses are steadily recorded within the first 3 s of stimulation and immediately after the
flash cessation EEG power at the stimulation frequency returns to the initial level. The resonance EEG responses were more
pronounced in the right hemisphere than in the left one, especially, at the stimulation frequencies of 6 and 16 Hz. With increasing
the stimulation frequency, the maximum of resonance EEG responses was reached earlier. Under the stimulation frequency of
6 Hz, the maximal response was recorded 9–12 s after the beginning of flashes, at the frequencies of 10 and 16 Hz, it was
recorded within 3–6 and 3 s, respectively. 相似文献
9.
Baclofen is a selective gamma-aminobutyric acid (GABA) type B agonist that may have important medicinal uses, such as in analgesics
and drug addiction treatment. In addition, evidence is accumulating that suggests GABAergic-mediated neurotransmission is
altered during aging. This study investigated whether baclofen administration (5 mg kg−1) induces differential effects on cortical electrical activity with age. Electroencephalograms (EEGs) were recorded from young
(3–4 months) and aged (15–17 months) rats, and both the absolute and relative powers in five frequency bands (delta: 2–4 Hz;
theta: 4–8 Hz; alpha: 8–12 Hz; beta: 12–20 Hz; gamma: 20–100 Hz) were analyzed. Before administration of baclofen, we found
that the EEG relative power in the beta band was higher in the aged than that in the young rats. After administration of baclofen,
there was a slower increase in the relative power in the delta band in the aged than that in the young rats. Moreover, there
was no significant difference between the two age groups in absolute power in any frequency band. These findings indicate
that baclofen treatment appears to differentially modify cortical EEG activity as a function of age. Our data further elucidate
the relationship between GABAB receptor-mediated neurotransmission and aging. 相似文献
10.
Vilma Kaškonienė Paulius Kaškonas Audrius Maruška Ona Ragažinskienė 《Acta Physiologiae Plantarum》2011,33(6):2377-2385
The variation in the content and composition of essential oils of Bidens tripartita L. grown in Lithuania has been studied using supercritical CO2 extraction followed by GC–MS. Extraction of essential oils was performed at two different pressures (9.1 and 15.1 MPa). Plant
material has been harvested at different phenological stages (from June to September). A total of 26 different compounds were
identified in the essential oils. The highest content and diversity of compounds was determined during the full-flowering
stage. Identified substances were mainly monoterpene hydrocarbons and sesquiterpene hydrocarbons. The main components were
α-pinene, p-cymene, trans-β-ocimene, and β-elemene. Chemometric analysis, including principal component and hierarchical cluster analyses, showed the
dependence of the essential oils qualitative as well as quantitative composition on the phenological stage the plant was collected
at. It also revealed that there was no correlation between age of the plant and quantity of the identified compounds. 相似文献
11.
Electrical activity recorded from the olfactory bulbs and prepyriform cortex of guinea pigs, rats, and mice under conditions
of spontaneous behavior and upon presentation of odor stimuli was analyzed in a comparative aspect. The dynamics of electrographic
phenomena observed in rhinencephalic structures and the spectral composition of these phenomena are discussed considering
the probability that the high-frequency components of this electrical activity are not directly related to realization of
the olfactory function.
Neirofiziologiya/Neurophysiology, Vol. 38, Nos. 5/6, pp. 440–447, September–December, 2006. 相似文献
12.
I. N. Konareva 《Neurophysiology》2009,41(1):54-62
In a group of 70 adult subjects of both sexes, we estimated the levels of the need for achievement and its motivation (interpreted
as generalized characteristics of the state of the motivational sphere of a personality and diagnosed using questionnaires
of Orlov and Mehrabian) and examined the correlations of these estimates with spectral powers (SPs) of the frequency components
(rhythms) of the current background EEG (С3 and С4 leads according to the 10–20 system). Despite the fact that naturally high
interindividual variability exists, high estimates of the need for achievement correlated with medium values of the SPs of
most EEG frequency components (δ, θ, α, and β1 rhythms), low SPs of the β2 and γ rhythms, and higher values of the coefficient of reactivity (CR) of the α rhythm. A high level of the need for achievement
corresponded to higher SPs of the θ and γ rhythms and high CR of the α rhythm, a medium SP of this EEG component, and lower
SPs of the δ and β rhythms. The coefficient of interhemisphere asymmetry of the α rhythm was the highest at low values of
the studied psychological indices. Interrelations that we found in our study can be explained as follows: both the characteristics
of the need for achievement and motivation typical of a certain personality and the amplitude parameters of the EEG rhythms
observed in this individual depend significantly on genetically determined factors (in particular, on neurochemical ones).
These peculiarities of neurodynamic constitution of the individual are, to a considerable extent, due to the specificity of
organization and functioning of a few neurotransmitter (aminergic, in particular) and neurohumoral systems.
Neirofiziologiya/Neurophysiology, Vol. 41, No. 1, pp. 61–69, January–February, 2009. 相似文献
13.
Nesrine Zahed Karim Hosni Nadia Ben Brahim Monem Kallel Houcine Sebei 《Acta Physiologiae Plantarum》2010,32(6):1221-1227
Gas chromatography-flame ionisation detection (GC-FID) and gas chromatography–mass spectrometry (GC–MS) analyses of the essential
oils of leaves and fruits of the ornamental Shinus molle L. were reported and their allelopathic effect on wheat (Triticum aestivum L.) was evaluated. Qualitative and quantitative differences between fruit and leaf oils were observed. Both oils were rich
in monoterpene hydrocarbons and the major constituents were limonene and β-phellendrene (35.9–65.4%), α-phellendrene (24.3–20.1%),
myrcene (12.8–7.7%) and α-pinene (5.9–1.7%) for fruits and leaves, respectively. Both essential oils showed a dose-dependent
allelopathic activity on wheat germination and radicle elongation with leaf oil being the more phytotoxic. 相似文献
14.
Ozaki TJ Sato N Kitajo K Someya Y Anami K Mizuhara H Ogawa S Yamaguchi Y 《Cognitive neurodynamics》2012,6(2):185-198
An ambiguous figure such as the Necker cube causes spontaneous perceptual switching (SPS). The mechanism of SPS in multistable
perception has not yet been determined. Although early psychological studies suggested that SPS may be caused by fatigue or
satiation of orientation, the neural mechanism of SPS is still unknown. Functional magnetic resonance imaging (fMRI) has shown
that the dorsal attention network (DAN), which mainly controls voluntary attention, is involved in bistable perception of
the Necker cube. To determine whether neural dynamics along the DAN cause SPS, we performed simultaneous electroencephalography
(EEG) and fMRI during an SPS task with the Necker cube, with every SPS reported by pressing a button. This EEG–fMRI integrated
analysis showed that (a) 3–4 Hz spectral EEG power modulation at fronto-central, parietal, and centro-parietal electrode sites
sequentially appeared from 750 to 350 ms prior to the button press; and (b) activations correlating with the EEG modulation
traveled along the DAN from the frontal to the parietal regions. These findings suggest that slow oscillation initiates SPS
through global dynamics along the attentional system such as the DAN. 相似文献
15.
Heart rate, EEG, and motor responses were recorded following presentation of a series of 6–10 sound stimuli (2.5-s tones of
1000, 4000, and 250 Hz, 70 dB, interstimulus intervals 18–25 s) in neonates aged 9 to 22 weeks during stage 2–3 sleep. The
infants (17 of 19) revealed heart rate (HR) changes in response to tone stimuli that consisted in an expanded form of three
phases: (1) short-latency (at 1 s after tone presentation) HR deceleration, (2) HR acceleration with a maximum at 3–5 s, and
(3) late HR deceleration at 6–9 s of the poststimulus interval. The occurrence rate of the first two phases of cardiac response
is relatively constant during a series of stimuli, whereas the likelihood of late HR deceleration is the highest following
the first tone presentation and decreases significantly when the stimulus is repeated. Differences in the dynamics and statistical
analysis allow a relative independence of all the three response phases to be suggested. The HR acceleration phase is dramatically
enhanced in association with the motor response elicited by the sound stimulus. The late HR deceleration phase occurs not
only after the first presentation of stimuli, but also when they are repeated if they evoke EEG reaction (vertex potentials)
in response to both the beginning and end of the tone sound. Possible mechanisms of the three phases of poststimulus HR changes
are: the vagal cardiac reflex associated with the acoustic (adaptive) reflex, activation of sympathetic efferents in combination
with the startle reflex, and secondary vagal deceleration of sinus rhythm likely to be associated with the processes of perception
(detection) of a “novel” stimulus and to serve as an indirect sign of an orienting reaction. 相似文献
16.
17.
We asked whether the large variability in odor imaging ability is underlain by interindividual differences in the processing of smells and emotion. Olfactory imaging ability, anhedonia level, and odor perception were measured in 40 subjects, using the Vividness of Olfactory Imagery Questionnaire (VOIQ), the Physical Anhedonia Scale, and the European Test of Olfactory Capabilities. "Good" olfactory imagers, defined primarily on the basis of the VOIQ, rated pleasant smells as more familiar and had lower anhedonia scores than "bad" olfactory imagers. Based on self-reported measures, these results suggest that, like olfactory perception, the mental imagery of smells is related to emotion and that, beyond their differences in vividness, good and bad olfactory imagers differ in their experience of emotion and long-term memory of smells. 相似文献
18.
The subjects were divided into two groups according to the α1 and α2 spectral powers in the occipital derivations of the EEG recorded in the initial state with their eyes closed. Group I included
subjects whose α1-rhythm spectral power (7–10 Hz) was more than 70% of the total α-rhythm band power. Group II included subjects whose α2-rhythm spectral power (10–13 Hz) was more than 70% of the total α-rhythm band power. It was established that, in the tasks
requiring prediction of the subsequent result (memorizing a certain sequence of signals and its subsequent reproduction on
the monitor screen), group I subjects differed from group II subjects in fewer sequence errors and a greater number of accurate
predictions. In group II subjects, a decrease in the ϑ-band spectral power in the EEG of the central and frontal cortical
areas was observed compared to the baseline. Therefore, the EEG ϑ-rhythm power at the memorizing stage was lower in them than
in group II subjects. The results suggest that the baseline characteristics of ϑ-activity can be regarded as prognostic criteria
of similar types of activity. 相似文献
19.
M. L. Ashkinazi 《Human physiology》2010,36(6):678-690
The spectral powers (SPs) of the θ and α EEG rhythms were studied at different stages of visual set in children from five
to seven years of age. Children with a plastic set had a greater α band SP than those with a rigid set. At the set formation
stage, children with a rigid set displayed an increase in the SP of the θ band, which is a manifestation of an “immature”
activation reaction. Children with a plastic set exhibited an increase in the α band SP in the occipital lobes of both hemispheres.
The dynamics of the SP of the EEG rhythms differed in children younger and older than six years. At the set formation stage,
children from five to six years of age exhibited the above-mentioned “immature” activation reaction, while those from six
to seven years of age showed an increase in the α band SP in the occipital lobes. At the set actualization stage, an increase
in the α band SP was observed in the right caudal areas, while the set extinction stage was marked by a bilateral depression
of the α band in the frontal lobes. The importance of the involvement of specific cortical areas in visual perception and
the formation of a plastic set is discussed. 相似文献
20.
Marrakchi M Vidic J Jaffrezic-Renault N Martelet C Pajot-Augy E 《European biophysics journal : EBJ》2007,36(8):1015-1018
This work shows the feasibility of an olfactory biosensor based on the immobilization of Saccharomyces cerevisiae yeast cells genetically modified to express the human olfactory receptor OR17-40 onto interdigitated microconductometric
electrodes. This olfactory biosensor has been applied to the detection of its specific odorant (helional) with a high sensitivity
(threshold 10−14 M). In contrast, no significant response was observed using a non-specific odorant (heptanal), which suggests a good selectivity.
Thus, this work may represent a first step towards a new kind of bioelectronic noses based on whole yeast cells and allowing
a real time monitoring of olfactory receptor activation.
Presented at the joint biannual meeting of the SFB-GEIMM-GRIP, Anglet, France, 14–19 October, 2006. 相似文献