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PubMed1988

[Measurement of dose fields using different detectors].

The authors presented and analyzed the results of measurement of dose fields of photon and electron radiation using 3 types of detectors (ionization camera, Si detector and diamond detector), alternately switched on to the CADSCAN dose field analyzer. The results of a study of dose fields of inhibitory radiation at 18 MeV were indicative of the similarity of data obtained with the help of diamond and Si detectors and an ionization camera. Comparison of the results for electron radiation at 4, 17 and 20 MeV showed that data obtained with the diamond detector, coincided with absorbed dose distributions calculated on the basis of ionization measurements whereas dose accumulation values obtained with the help of the Si detector were very high.

Radiation Dosage↗
PubMed1993

[Steroid dominance, enzyme activity and morphological appearance of granulosa cells in the largest follicles in cows].

The cyclic nature of the female reproduction process depends to a considerable degree on the unique capacity of ovarial follicles to change their structure and function. The differentiation process during folliculogenesis takes place in all parts of the follicle. Granulosa cells reflect a high degree of structural changes and play an important role in functional maturation of the inert follicle. Changes in the reaction to endocrine and paracrine effects from a unique environment that is inevitably necessary for oocyte growth and ovulation were reached by changes in the biochemical activity and the internal anatomic mutual relation of the follicle (Linder et al., 1976; Hsueh, 1976). This growth process and differentiation depend on gonadotropic stimulation of the follicles and the quantity of receptor sites able to bind them. The aim of this work was compare estradiol 17-beta and progesterone levels in the follicular fluid of the largest follicles with the morphological structure and enzymatic activity of membrana granulosa cells. Ovaries were obtained from 34 SS x LBS randomly chosen cows at the slaughter-house. Follicular fluid to estradiol 17-beta and progesterone level determination was obtained by aspiration of the largest follicles. Estradiol 17-beta and progesterone levels were determined by RIA sets from the URVJT (Institute of Radioecology and Use of Nuclear Techniques) in Kosice, type RIA-test-ESTRA (SI-125-129) and RIAA-test-Prog (SI-125-6), respectively. With the methods used the variation coefficient of intra- and interassay for the estradiol 17-beta of the RIA set were 10.1 and 13.3%, for progesterone of the RIA set these values were 11.4 and 13.7% respectively. Steroid dominance of follicles was determined by the method described by Căllesen et al. (1986), based on the expression of the index of the mutual relation between progesterone levels and estradiol 17-beta was levels. Excisions from the follicular wall were examined under the scanning electron microscope JEOC 1200 Mx at an acceleration voltage of 20 kV. In granulosa cell smears acid phosphatase and non-specific esterase activity were determined by incubation in the incubation media according to Lojda et al. (1979). Steroid levels are given in nmol/l +/- SEM. Mean estradiol 17-beta levels in estrogen dominant follicles were proved to be 2170.0 +/- 1605.3 nmol/l, whereby individual concentrations ranged from 17.0 nmol/l to 10180.0 nmol/l.(ABSTRACT TRUNCATED AT 400 WORDS)

Acid Phosphatase↗
PubMed2006

First-principles calculation of alloy scattering in Ge(x)Si(1-x).

First-principles electronic structure methods are used to find the rates of intravalley and intervalley n-type carrier scattering due to alloy disorder in Si(1-x)Ge(x) alloys. The required alloy scattering matrix elements are calculated from the energy splitting of nearly degenerate Bloch states which arises when one average host atom is replaced by a Ge or Si atom in supercells containing up to 128 atoms. Scattering parameters for all relevant Delta and L intravalley and intervalley alloy scattering are calculated. Atomic relaxation is found to have a substantial effect on the scattering parameters. f-type intervalley scattering between Delta valleys is found to be comparable to other scattering channels. The n-type carrier mobility, calculated from the scattering rate using the Boltzmann transport equation in the relaxation time approximation, is in excellent agreement with experiments on bulk, unstrained alloys.

Journal Article↗
PubMed2000

Type D personality. A potential risk factor refined.

OBJECTIVE: Acute and chronic psychological distress have been associated with coronary heart disease (CHD) but little is known about the determinants of distress as a coronary risk factor. Broad and stable personality traits may have much explanatory power; this article selectively focuses on negative affectivity (NA; tendency to experience negative emotions) and social inhibition (SI; tendency to inhibit self-expression in social interaction) in the context of CHD. METHODS: The first part of this article reviews research on NA and SI in patients with CHD. The second part presents new findings on NA and SI in 734 patients with hypertension. RESULTS: Accumulating evidence suggests that the combination of high NA and high SI designates a personality subtype ("distressed" type or type D) of coronary patients who are at risk for clustering of psychosocial risk factors and incidence of long-term cardiac events. Type D and its contributing low-order traits (dysphoria/tension and reticence/withdrawal) could also be reliably assessed in a community-based sample of patients with hypertension. This finding was replicated in men and women, and in Dutch- and French-speaking subjects. Type D hypertensives reported more depressive affect than their non type D counterparts. CONCLUSIONS: There is an urgent need to adopt a personality approach in the identification of patients at risk for cardiac events. NA and SI are broad and stable personality traits that may be of special interest not only in CHD, but in other chronic medical conditions as well.

Adaptation, Psychological↗
PubMed1994

Identification of a melanosomal matrix protein encoded by the murine si (silver) locus using "organelle scanning".

To identify a broad spectrum of melanosomal proteins, antisera were raised in rabbits against melanosomal protein fractions separated on the basis of their solubility in the nonionic detergent Triton X-114. Antisera against the different fractions each recognized a distinct set of bands when used for immunoblotting analysis with extracts of melanocytes cultured from wild-type black mice. Immunoblotting with antisera to whole melanosomes or to Triton X-114-soluble melanosomal proteins that segregated with the detergent phase gave identical patterns with protein extracts from melanocytes from wild-type mice and from mice homozygous for the si (silver) coat color mutation. By contrast, an antiserum against Triton X-114 soluble melanosomal proteins that segregated in the aqueous phase recognized an 85-kDa protein that was present in extracts from wild-type melanocytes but was absent from si melanocytes. This suggested that the protein was encoded at the si (silver) locus. This was confirmed by employing an antiserum directed against the carboxyl terminus of the predicted murine silver protein sequence. The detergent solubility, biochemical characteristics, and immunologic properties of the 85-kDa protein and of the authentic si gene product were identical. Further analysis demonstrated that this protein corresponds to a melanosomal matrix glycoprotein that we recently described. Our results suggest that employing polyclonal antisera to fractionated organelles such as melanosomes, to screen tissues from mutant mice, a technique that we call "organelle scanning", can serve as a powerful means of identifying new organellar proteins and their respective genes.

Animals↗
PubMed2001

Pi-donation and stabilizing effects of pnicogens in carbenium and silicenium ions: a theoretical study of [C(XH2)3]+ and [Si(XH2)3]+ (X = N, P, As, Sb, Bi).

Quantum chemical calculations at the MP2 and CCSD(T) levels of theory are reported for cations of the general type [A(XH2)3]+ with A = C, Si and X = N, P, As, Sb, Bi. Population analysis, methyl stabilization energies (MSEs), and structural criteria were used to predict the p(pi)-donor ability of and the pi-stabilization energy exerted by this series of pnicogens. All of the substituents XH2 considered in these studies invariably stabilize the triply substituted carbenium as well as the silicenium ions. The calculated data show that the intrinsic p(pi)-donation of the group 15 atoms follows the order N < P < As < Sb < Bi. However, the trend of the stabilization energies is fully reversed. The intrinsic stabilization energies of the planar carbenium ions decrease monotonically from 161.2 kcal mol(-1) for X = NH2 to 98.0 kcal mol(-1) for X = BiH2. The effective stabilization of the pnicogens in the equilibrium structures, which also includes the energy-demanding pyramidalization of the XH2 substituents, follows the same trend, although the absolute numbers are reduced to 145.6 kcalmol(-1) for X = NH2 and 53.2 kcalmol(-1) for X = BiH2. This seemingly contrasting behavior of increasing p(pi) charge donation and decreasing stabilization has already been found for other substituents. Previous studies have shown that carbenium ions substituted by chalcogens up to the fourth row also stabilize C+ less effectively with respect to heavier substituents. Of the ions investigated in this study, only the silicenium ions that are stabilized by pnicogens from the third to the sixth row of the periodic system yield increased stabilizing energies that follow the corresponding intrinsic p(pi)-donor abilities of the respective substituent.

Journal Article↗
PubMed1983

The effects of stimulation of substantia innominata and sensory receiving areas of the forebrain upon the activity of neurons within the amygdala of the anesthetized cat.

The present study investigated the response characteristics of individual neurons in the amygdala following stimulation of the substantia innominata (SI), and compared these responses with those elicited by stimulation of insular and temporal polar cortices and the lateral olfactory tract (LOT). Recordings were made from single units within the medial, central, basal, and lateral amygdaloid nuclei of anesthetized, male cats. Stimulating electrodes were located in the SI, LOT, and sylvian cortex (SG). Unit responses were classified as either excitation or inhibition. Excitatory responses were further divided into fixed latency excitation (FLE) and variable latency excitation (VLE) based on the variability of the onset latency of the response. The majority of responses to SI stimulation were of the FLE type, implying a direct orthodromic, monosynaptic activation of amygdaloid units. Proportionally more FLE responses were recorded laterally, especially in the magnocellular basal nucleus, compared to VLE responses which were more common in the medial and central nuclei. SI stimulation consistently affected the activity of many more units than did SG or LOT stimulation. The onset latencies of the population of cells exhibiting excitatory responses elicited by SI stimulation were distributed bimodally, and this may reflect a dual projection pathway of amygdaloid afferents from this basal forebrain region. This correlates with anatomical descriptions indicating that SI projections to amygdala pass via the ventral amygdalofugal pathway as well as in the stria terminalis. Excitatory onset latencies of responses to SI stimulation were the shortest in the lateral and magnocellular basal nuclei and the longest in the parvocellular basal nucleus. Amygdaloid units exhibited convergent input from the stimulus sites. A clear topographical distribution of units was not demonstrated. The data suggests that units receiving a convergent input were rarely driven monosynaptically by more than one stimulus site. The basal nucleus contained the smallest fraction of units exhibiting a convergent input. A small population of antidromic responses was recorded and indicates that within the system studied the caudal aspect of the basal nucleus is a major source of amygdaloid efferents. Antidromically driven units did not exhibit transynaptic responses following stimulation of any of the test sites.

Afferent Pathways↗
PubMed2003

T cells and autoantibodies to human HSP70 in type 1 diabetes in children.

We studied T-cell proliferative responses (stimulation index: SI) and autoantibodies to human HSP60, HSP70 and HSP90 proteins in 25 children (mean age 10.1+/-3.8 years) newly diagnosed with Type 1 diabetes. The control group for T cells included 25 adults and three pediatric donors without Type 1 diabetes. Controls for antibodies included 10 pediatric subjects. The T-cell responses to HSP70 of the test group (mean SI=4.5+/-3.1) were significantly greater than those of the control group (meanSI=1.4+/-0.6; p<0.0001); the incidence of HSP70 responders was (85%) compared to 14% in the control group. All but three of the Type 1 children who responded to HSP70 also responded to HSP60 (85%). The T-cell responses of the Type 1 group to HSP90 (mean SI=1.7+/-1.1) were similar to those of the control group (mean SI=1.5+/-0.7). We mapped HSP70 epitopes recognized by T cells in seven subjects using overlapping peptides of the molecule. Among the Type 1 subjects, IgG seropositivity was 45% to HSP60, 30% to HSP70, and 15% to HSP90. Thus, we conclude that children with newly diagnosed Type 1 diabetes manifest heightened T-cell autoimmunity to HSP70 and HSP60, but not to HSP90.

Adolescent↗
PubMed2001

The semantic interference effect in the picture-word paradigm: an event-related fMRI study employing overt responses.

We used event-related functional magnetic resonance imaging (fMRI) to investigate neural responses associated with the semantic interference (SI) effect in the picture-word task. Independent stage models of word production assume that the locus of the SI effect is at the conceptual processing level (Levelt et al. [1999]: Behav Brain Sci 22:1-75), whereas interactive models postulate that it occurs at phonological retrieval (Starreveld and La Heij [1996]: J Exp Psychol Learn Mem Cogn 22:896-918). In both types of model resolution of the SI effect occurs as a result of competitive, spreading activation without the involvement of inhibitory links. These assumptions were tested by randomly presenting participants with trials from semantically-related and lexical control distractor conditions and acquiring image volumes coincident with the estimated peak hemodynamic response for each trial. Overt vocalization of picture names occurred in the absence of scanner noise, allowing reaction time (RT) data to be collected. Analysis of the RT data confirmed the SI effect. Regions showing differential hemodynamic responses during the SI effect included the left mid section of the middle temporal gyrus, left posterior superior temporal gyrus, left anterior cingulate cortex, and bilateral orbitomedial prefrontal cortex. Additional responses were observed in the frontal eye fields, left inferior parietal lobule, and right anterior temporal and occipital cortex. The results are interpreted as indirectly supporting interactive models that allow spreading activation between both conceptual processing and phonological retrieval levels of word production. In addition, the data confirm that selective attention/response suppression has a role in resolving the SI effect similar to the way in which Stroop interference is resolved. We conclude that neuroimaging studies can provide information about the neuroanatomical organization of the lexical system that may prove useful for constraining theoretical models of word production.

Adult↗
PubMed1996

Intraepithelial lymphocytes in colon have similar properties to intraepithelial lymphocytes in small intestine and hepatic intermediate TCR cells.

Recently, properties of intraepithelial lymphocytes (IEL) in the colon (C-IEL) have been analyzed in comparison with those of IEL in the small intestine (SI-IEL). We compared the properties of C-IEL with those of SI-IEL and hepatic intermediate TCR cells, two other types of extrathymic T cells. C-IEL and intermediate TCR cells contain many NK1+T cells, although SI-IEL contain few. V gamma and V delta usage of C-IEL was the same as that SI-IEL, and that of intermediate TCR cells was different. C-IEL responded to Con A while SI-IEL did not. As to adhesion molecules, C-IEL include both extrathymic and thymus-originated type T cells. With age, TCR- alpha beta(+) CD4+ CD8+ cells do not increase among C-IEL but do increase among SI-IEL. IL-2R beta(+) or CD4- CD8- C-IEL increase as observed in the liver. These results indicate that these organ-specific T cells have different roles at their respective sites and that they may be of different lineages.

Animals↗
PubMed2000

Observation of disorder-induced 2D mott-hubbard states of the alkali-earth metal (Mg,Ba)-adsorbed Si(111) surface

We report evidence of a disorder-driven Mott-Hubbard-type localization on the alkali-earth metal (AEM) (Mg,Ba)-adsorbed Si(111)-(7x7) surface. The clean metallic Si(111) surface is found to undergo a two-dimensional (2D) metal-insulator transition as randomly distributed AEM adsorbates cause disorder on the surface. A well-defined electron-energy-loss peak unique to the insulating phase is attributed to an interband excitation between the split Hubbard bands originated from a metallic surface band at Fermi energy. A quantitative analysis of the loss peak reveals that the AEM-induced insulating surfaces are of a Mott-Hubbard type driven essentially by disorder.

Journal Article↗
PubMed1986

Callosal projections from area SII to SI in monkeys: anatomical organization and comparison with association projections.

The present research was aimed at ascertaining in the macaque monkey the reciprocity of the heterotopical callosal connections between SI and SII, with particular regard to the connectivity of the hand representation, and at comparing the topographical and laminar pattern of these callosal connections with those of association connections entertained by these areas. Horseradish peroxidase (HRP) was unilaterally injected into area SI in five monkeys. The sites of HRP delivery included the trunk and the hand zones preliminarily identified by recording multi-unit responses to peripheral stimulation by means of microelectrodes. Anterograde and retrograde labelling was studied in SII of both sides. The results showed the complete reciprocity of the heterotopical callosal connections between SI and SII. In the latter area both callosal axon terminals and neurones were found, which were labelled from either the trunk or the hand zone of contralateral SI. Labelling of callosal axon terminals occurred mainly in layer IV and in the lowermost part of layer III. Labelled callosal neurones were mainly in the lower half of layer III, whereas few occurred in infragranular layers. Topographically, the distribution of callosal terminals and cell bodies duplicated the distribution of association terminals and cell bodies labelled in SII on the side ipsilateral to HRP injection. The laminar pattern of termination of association fibres from SI was similar to that of callosal fibres. However, the distribution of association-projecting neurones in SII showed a striking difference from that of callosal-projecting neurones. Unlike the latter neurones, which were mainly located in supragranular layers, association cell bodies overwhelmingly dwelt in layers V and VI and were less numerous in layers II and III. This laminar pattern of association SII-SI cells corresponds to the "feed-backward" model and fits the laminar pattern of their axon terminations (Friedman: Brain Res. 273: 147-151, '83). The association and callosal inputs and outputs of area SII are discussed in relation to the function of the forward and backward type of reciprocal connections entertained with SI in the ipsilateral hemisphere and to the function of SII in the interhemispheric exchange of somatosensory information.

Animals↗
PubMed2006

Reactivity of free thiol groups in type-I inositol trisphosphate receptors.

The IP3R (inositol 1,4,5-trisphosphate receptor) Ca2+-release channel is known to be sensitive to thiol redox state. The present study was undertaken to characterize the number and location of reactive thiol groups in the type-I IP3R. Using the fluorescent thiol-reactive compound monobromobimane we found that approx. 70% of the 60 cysteine residues in the type-I IP3R are maintained in the reduced state. The accessibility of these residues was assessed by covalently tagging the IP3R in membranes with a 5 kDa or 20 kDa MPEG [methoxypoly(ethylene glycol) maleimide]. MPEG reaction caused a shift in the mobility of IP3R on SDS/PAGE that was blocked by pretreatment of the membranes with dithiothreitol, N-ethylmaleimide, mersalyl or thimerosal, indicating that MPEG reactivity was specific to thiol groups on the IP3R. Trypsin cleavage of the type-I IP3R generates five defined domains. In cerebellum membranes, MPEG reacted over a 5 min interval with tryptic fragment I and fragment III, but not fragments II, IV or V. Fragment I appears as a doublet in cerebellum membranes, corresponding to the presence and absence of the SI splice site in this region (SI is a spliced domain corresponding to amino acids 318-332). Only the fragment I band corresponding to the SI(+) splice form shifted after reaction with MPEG. Expression of SI(+) and SI(-) spliced forms in COS cell microsomes confirmed this result. The MPEG-induced shift was not prevented when the cysteine residue present in the SI splice domain (C326A) or the remaining seven cysteine residues in fragment I were individually mutated. Of the combination mutations screened, only the mutation of C206/214/326A blocked MPEG reactivity in fragment I. We conclude that a set of highly reactive cysteine residues in fragment I are differentially accessible in the SI(+) and SI(-) splice variants of the type-I IP3R.

Alternative Splicing↗
PubMed1990

[Characterization of the neurons of the basal forebrain complex in the rat: A Nissl- and Golgi impregnation study].

Nissl stained neurons were classified in some nuclei of the basal forebrain complex of the rat (Nc. septi medialis, MS; vertical limb of the nucleus of the diagonal band, vDB; horizontal limb of the nucleus of the diagonal band, hDB; Nc. preopticus magnocellularis, NPM; Substantia innominata, SI; Nc. basalis Meynert, NB). Several types of neurons are coexistent in each of these nuclei. They differ in soma size and shape, but also in their cytoplasmic and nuclear texture. We found three classes of neurons as well in the MS-vDB, as in the hDB and NPM, but five classes in the SI-NB complex. On the basis of these findings some conclusions were drawn regarding the cytoarchitecture of this region, as the demarcation of vDB and hDB and of hDB and NPM. The borderline between vDB and hDB was found to be undefinable in Nissl stained preparations, whereas the NPM is characterized by its high content of giant neurons in cotontrast the adjacent hDB. Additionally, we tried to identify the Nissl stained neurons on the basis of soma features with Golgi impregnated neurons. The daimpregnations of Golgi impregnated neurons enabled us to compare the width of the cytoplasm and the nuclear position of neurons stained after these methods. From the thirteen classes of neurons described in Golgi investigations, 8 were identified in Nissl stained sections through this region of the rat's forebrain.

Animals↗
PubMed1990

Transformation of animal cells with human T-cell leukemia virus type II.

Human T-cell leukemia virus type II (HTLV-II) was tested for its ability to transform normal animal cells. The HTLV-II-infected human T-cell line, HTLV-IIA was lethally X-irradiated and cocultivated with normal leukocytes of rabbit and crab-eating monkey and spleen cells of hamster. The transformed cell lines, designated Ra-IIA, Si-IIA and Ham-IIA, were established. These cell lines were shown to be infected with HTLV-II by the polymerase chain reaction method combined with the digoxigenin-enzyme-linked immunosorbent assay method. These cell lines were examined for viral antigens by the indirect immunofluorescence method. Although the cytoplasma of over 90% of the cells of Si-IIA cell line was brilliantly stained, Ra-IIA and Ham-IIA cells were not stained. Electron microscopy of cells of the Si-IIA line revealed C-type virus particles in the extracellular spaces.

Animals↗
PubMed1999

Varicella immunity: persistent serologic non-response to immunization.

OBJECTIVE: Varicella-zoster (VZV) infection is an occupational hazard for health care workers. The "gold standard" for assessing protection is a positive antibody titer. We present a case of persistent serologic non-responsiveness following VZV immunization and discuss a management strategy. METHODS: A 29-year-old woman, immunocompetent pediatric resident was repeatedly removed from her clinical duties because of a negative history of chicken pox and the absence of a VZV antibody titer. She received a total of three doses of the VZV vaccine and continued to have a negative antibody titer as measured by a commercial ELISA assay (Wampole). Subsequently, she had three direct contacts with infectious children and did not develop clinical chicken pox. RESULTS: A lymphocyte proliferation assay was performed using inactivated varicella vaccine and tetanus antigens. The patient's varicella and tetanus stimulation index (SI) were 46.5 and 42, respectively. The SI for the positive control (a patient recently recovered from a wild type infection) were 144 (varicella specific), and 114 (tetanus). The SI secondary to VZV antigens reported in the literature is 30.5 +/- 9.1. We reassessed the varicella antibody titer using more sensitive assays: fluorescent antibody to membrane antigen and latex agglutination. Both tests verified the presence of VZV specific IgG at a titer of 1:8 in our patient. CONCLUSION: This case illustrates that in a subgroup of individuals the antibody response to VZV vaccine may be low despite an adequate cell-mediated response. Commercial VZV ELISA assays were designed to measure higher titers associated with natural infection rather than the lower titer induced by the vaccine. Repeated immunizations plus more sensitive measures of VZV-specific IgG should be used to validate protection rather than the current commonly utilized ELISA screening. Clinicians should be aware of the variability in VZV-specific antibody assays when assessing post VZV vaccine titers prior to determining protection in health care workers.

Adult↗
PubMedDate not supplied

The differential diagnosis of pancreatic cysts by MR imaging.

BACKGROUND/AIM: The usefulness of magnetic resonance imaging (MR imaging) in the differential diagnosis of cystic lesions of the pancreas was assessed. METHODS AND MATERIALS: Pseudocyst was present in 9 patients, retention cyst in 4, simple cyst in 2, serous cystadenoma in 1, mucinous cystadenoma in 6, mucinous cystadenocarcinoma in 6. The relative signal intensity (SI) of each cystic lesion on MR imaging was assessed in comparison with that of the liver. RESULTS: It was difficult to distinguish the cystic types from each other based on the SI on MR images. Insofar as mucinous cystic tumors, those containing gelatinous mucin showed higher SI on T1-weighted images than those containing mucinous but watery fluid. five of the 6 mucinous cystic tumors containing gelatinous mucin were histologically malignant, whereas all except one those containing watery fluid were benign. CONCLUSIONS: Our results suggest that the SI on T1-weighted images may be useful in distinguishing malignant from benign mucinous cystic tumors.

Adult↗
PubMed2001

Differential coding of pain intensity in the human primary and secondary somatosensory cortex.

The primary (SI) and secondary (SII) somatosensory cortices have been shown to participate in human pain processing. However, in humans it is unclear how SI and SII contribute to the encoding of nociceptive stimulus intensity. Using magnetoencephalography (MEG) we recorded responses in SI and SII in eight healthy humans to four different intensities of selectively nociceptive laser stimuli delivered to the dorsum of the right hand. Subjects' pain ratings correlated highly with the applied stimulus intensity. Activation of contralateral SI and bilateral SII showed a significant positive correlation with stimulus intensity. However, the type of dependence on stimulus intensity was different for SI and SII. The relation between SI activity and stimulus intensity resembled an exponential function and matched closely the subjects' pain ratings. In contrast, SII activity showed an S-shaped function with a sharp increase in amplitude only at a stimulus intensity well above pain threshold. The activation pattern of SI suggests participation of SI in the discriminative perception of pain intensity. In contrast, the all-or-none-like activation pattern of SII points against a significant contribution of SII to the sensory-discriminative aspects of pain perception. Instead, SII may subserve recognition of the noxious nature and attention toward painful stimuli.

Adult↗