bluuebunny/crossref_metadata_2025 huggingface dataset:
The role of sodium dodecyl sulfate (SDS) micelles in inducing skin barrier perturbation in the presence of glycerol
Authors: Ghosh Saswata , Blankschtein Daniel
Published: September 2010

The stratum corneum (SC) serves as the skin barrier between the body and the environment. When the skin is contacted with an aqueous solution of the surfactant sodium dodecyl sulfate (SDS), a well‐known model skin irritant, SDS penetrates into the skin and disrupts this barrier. It is well established, both in vitro and in vivo, that the SDS skin penetration is dose‐dependent, and that it increases with an increase in the total SDS concentration above the critical micelle concentration (CMC) of SDS. However, when we added the humectant glycerol at a concentration of 10 wt% to the aqueous SDS contacting solution, we observed, through in vitro quantitative skin radioactivity assays using 14C‐radiolabeled SDS, that the dose dependence in SDS skin penetration is almost completely eliminated. To rationalize this important observation, which may also be related to the well‐known beneficial effects of glycerol on skin barrier perturbation in vivo, we hypothesize that the addition of 10 wt% glycerol may hinder the ability of the SDS micelles to penetrate into the skin barrier through aqueous pores that exist in the SC. To test this hypothesis, we conducted mannitol skin permeability as well as average skin electrical resistivity measurements in vitro upon exposure of the skin to an aqueous SDS contacting solution and to an aqueous SDS + 10 wt% glycerol contacting solution in the context of a hindered‐transport aqueous porous pathway model of the SC. Our in vitro studies demonstrated that the addition of 10 wt% glycerol: (i) reduces the average aqueous pore radius resulting from exposure of the skin to the aqueous SDS contacting solution from 33 ± 5Å to 20 ± 5Å, such that a SDS micelle of radius 18.5 ± 1Å (as determined using dynamic light‐scattering measurements) experiences significant steric hindrance and cannot penetrate into the SC, and (ii) reduces the number density of aqueous pores in the SC by more than 50%, thereby further reducing the ability of the SDS micelles to penetrate into the SC and perturb the skin barrier.
Multicenter study on measurement of the natural pH of the skin surface
Authors: Segger D. , Aßmus U. , Brock M. , Erasmy J. , Finkel P. , Fitzner A. , Heuss H. , Kortemeier U. , Munke S. , Rheinländer T. , Schmidt‐Lewerkühne H. , Schneider W. , Weser G. ,   [Members of the DGK German Society for Scientific and Applied Cosmetics »Skin Cleansing« Group]
Published: September 2010

Characterization of the skin's natural state is very important for understanding skin functions and describing disturbances of skin function. In the field of cosmetics and dermatologicals the natural pH of the skin surface plays an important role in the development of products with a skin neutral pH. In a multicenter study the natural pH of the skin surface (exception of underarm and genital areas), was to be measured. It was to be determined whether gender‐specific differences in the pH occur. The skin surface pH was measured on the inside of the forearms in 222 volunteers (147 female, 75 male) using the skin pH meters of the respective institutes. The pH was measured in triplicate on adjacent areas 24 h after the last contact of the measuring site with water, topical applications and an intensive washing procedure. The values of the skin surface pH were 4.9 (arithmetic mean). The 95% interval was between 4.1 and 5.8. The pH on the forearm of the male volunteers was slightly lower than that of the females. The difference was statistically significant (p < 0.01; 4.8 to 5.0). The authors suggest that the GDCh recommendations for the claims »skin neutral pH«, »ideal pH« or »skin‐friendly pH« should be revised and propose a pH range of 4.1 to 5.8 for the main body areas excluding the underarm and genital areas.
Effect of microalgal extracts on thioredoxin expression in human skin cells and their protection of skin
Authors: Morvan P‐Y. , Vallee R.
Published: September 2010

Skin is the constant target of active forms of oxygen generated by UV radiation exposure. It needs to reinforce anti‐oxidant defense mechanisms to protect itself against cell damage. Thioredoxin is a protein found extensively in animals, plants and marine bacteria. It protects cells against the cytotoxicity produced by free radicals. An increase in thioredoxin production could be thus an interesting way to improve skin cell protection. We studied thioredoxin expression in human skin cells by minichips, and the results were confirmed by RT‐PCR. Protein expression was quantified by Western blot. Thioredoxin mRNA is expressed by human dermal fibroblasts and epidermal keratinocytes. The thioredoxin protein was detected in both types of human skin cells and visualized in human reconstituted epidermis. Some stress‐resistant micro‐algae also express protective proteins. We tested the effect of two micro‐algal extracts on the level of thioredoxin expression in human skin cells and on the protection against free radicals by measuring the inhibition of superoxide anion, on the protection against polluting agents by measuring cellular vitality and on the protection of Langerhans cells against UV exposure. By stimulating the thioredoxin level, the micro‐algal extracts protect skin cells against several types of free radical generating systems.
Design and development of an innovative hybrid powder based on a computer simulation and its application to foundation makeup products
Authors: Ogawa Katsuki , Yagi Katsuhiko , Hata Hideo , Miura Yoshimasa , Nakamura Koichi , Takata Sadaki , Fujima Kazumi
Published: September 2010

An innovative hybrid powder prepared using computer simulation allowed development of a new foundation having a fine, smooth texture that has never been achieved before. The optical structure/design of the powder was based on the results of measurements and analyses conducted on the optical characteristics of a baby's delicate skin, which is the envy of many women. To obtain the optimal optical characteristics, the finite differential time domain (FDTD) method for solving Maxwell's differential equation by difference and time domain was applied to the computer simulation method. For synthesis of the hybrid powder based on the optical model, a proprietary shape regulation coating technology was used in which flaky substrates were coated with microspherical forms of barium sulfate crystals. The hybrid powder developed exhibited optical characteristics that showed a significant diffusion characteristic in the visible light region. The foundation containing this powder could conceal pores, small wrinkles, freckles, and age spots and owing to its microscopic reflection characteristics provided a fine, smooth texture that has never before been available with a conventional foundation.
Increased carbonyl protein levels in the stratum corneum of the face during winter
Authors: Kobayashi Y. , Iwai I. , Akutsu N. , Hirao T.
Published: September 2010

Synopsis

The stratum corneum (SC) is the interface between the body and the environment, and is continuously exposed to oxidative stress that results in carbonyl modification of proteins. We previously developed a simple and non‐invasive method to assess the stratum corneum carbonyl protein (SCCP) levels. In this study, we used this method to examine the seasonal changes in the SCCP levels and the relationship between the SCCP level and the physiological condition of the SC. SC was collected from the face of healthy Japanese volunteers by adhesive tape stripping and its carbonyl groups were determined by reaction with fluorescein‐5‐thiosemicarbazide. The average fluorescence intensity of the SC was calculated as the SCCP level. The SCCP level in the cheek was higher in winter than summer. The SCCP level was negatively correlated with the water content in the SC measured by the conductance and capacitance, and also negatively correlated with the extensibility of the skin measured by a Cutometer, suggesting that the mechanical properties of the skin can be affected by oxidative modification of the SC. These data suggest the involvement of oxidative modification of SC proteins in the generation of rough skin during winter.
Confocal Raman microspectroscopy of stratum corneum: a pre‐clinical validation study
Authors: Wu J. , Polefka T. G.
Published: September 2010

Synopsis

Skin moisturization is not only important for maintaining skin functional properties but also has great impact on the skin’s aesthetic properties. The top layer of the skin, the stratum corneum (SC), plays a key role in protecting and preventing against external aggressions as well as in regulating water flux in and out. Confocal Raman microspectroscopy is the first commercially available technique that provides a non‐invasive, in vivo method to determine depth profiles of water concentration in the skin, however, in this case it was applied in an in vitro setting. As the first phase of validating the usefulness of confocal Raman microspectroscopy, we used porcine skin as a surrogate for human skin. Water concentration profiles were obtained using confocal Raman microspectroscopy from isolated pigskin SC and compared with that using the Karl Fischer titration method. The two methods correlated very well with a regression coefficient of 1.07 as well as a correlation coefficient, R2 = 0.989, which demonstrated the consistency and accuracy of confocal Raman microspectroscopy for water concentration determination. To evaluate the instrument’s response to different skin care/cleansing products, a wide range of products were tested to compare their skin moisturization ability. Among those tested were a lotion, commercial soap bar, syndet bar, traditional non‐emollient shower gel (water, Sodium Laureth Ether Sulfate (SLES), cocamidopropyl betaine system) and emollient containing shower gel (water, sunflower oil, SLES, cocamidopropyl betaine, glycerin, petrolatum). The results were consistent with what was expected. The water content on skin treated with (A) lotion was significantly higher than the non‐treated control; (B) syndet bar‐treated skin had a significantly higher water content than soap‐based bar‐treated sites; (C) non‐emollient shower gel washed sites were more moisturized than soap‐based bar‐treated samples; and (D) emollient shower gel‐treated skin was significantly more hydrated than non‐emollient shower gel washed skin. The unique and direct quantitative water content information provided by confocal Raman microspectroscopy offers a whole new perspective for fundamental skin moisturization studies and will play an important role in evaluating moisturizing profiles and the hydration potential of products designed for personal care in the cosmetic industry.
Topical granulocyte colony‐stimulating factor for the treatment of oral and genital ulcers of patients with Behçet's disease
Authors: Bacanli A , Yerebakan Dicle O , Parmaksizoglu B , Yilmaz E , Alpsoy E
Published: September 2010

Background  Recurrent and painful ulcers of the oral mucosa and genital skin/mucosa are the most commonly observed manifestations in patients with Behçet's disease (BD). They affect patients’ quality of life. Because of the effectiveness of granulocyte colony‐stimulating factor (G‐CSF) in wound healing, it may also be useful for the treatment of oral ulcers (OU) and genital ulcers (GU) of BD.

Objective  We aimed to determine the efficacy of topically applied G‐CSF in the treatment of OU and GU of BD.

Methods  Seven patients with BD diagnosed according to the criteria of the International Study Group for Behçet's Disease were involved in the study. The patients were observed for 3 months before the study, and all occurrences were recorded during this period. Patients were given topical G‐CSF for OU (4 × 120 µg/day, for 5 days) and/or GU (4 × 30 µg/day, for 5 days) and followed‐up for 3 months after treatment. No concurrent disease‐specific or immunosuppressive topical or systemic drugs were given during the study period.

Results  G‐CSF treatment decreased the healing time and pain of OU and GU in six of seven patients compared with the pretreatment period. However, the effectiveness of the G‐CSF treatment on OU and GU healing time and pain severity did not continue during the post‐treatment period.

Conclusions  G‐CSF has beneficial effects on the healing duration and pain severity of OU and GU of patients with BD. However, given the high cost, impractical preparation and inability to cure the disease, G‐CSF treatment should be chosen only in selected patients.
Contact allergy to corticosteroids and Malassezia furfur in seborrhoeic dermatitis patients
Authors: Ljubojevic S , Lipozencic J , Basta‐Juzbasic A
Published: September 2010

Background  Seborrhoeic dermatitis (SD) is a chronic skin disease, requiring long‐term treatment, which might promote sensitization. Malassezia furfur (Mf) plays an important role in seborrhoeic dermatitis.

Objectives  The aim of this study was to determine the frequency of contact sensitivity in SD patients.

Patients and methods  A total of 100 patients and 20 healthy controls (HC) were investigated: 50 suffering from SD with no previous local corticosteroid treatment (SDN), 50 SD patients treated with local corticosteroids (SDC). Mycological examination for Mf was performed. All patients were patch tested with the baseline standard, corticosteroid series, with 12 commercial corticosteroid preparations frequently used in Croatia; and also with Mf.

Results  Malassezia furfur was found in 44 (88%) SDN, 37 (74%) SDC, and in 4 (20%) HC; patch test reaction to Mf was positive in one SDN and in three SDC. Positive patch tests to standard allergens were observed in 17 (34%) SDN, 33 (66%) SDC and 2 (10%) HC. Patch tests to the corticosteroid series revealed positive reactions in 4 SDC and to commercial corticosteroids in seven patients, i.e. 2 SD and 5 SDC.

Conclusions  Patch tests to the baseline series and to both individual corticosteroid and commercial corticosteroid preparations should be performed in SD patients with persistent dermatitis, as contact‐allergic reactions may complicate their dermatitis. Sensitization to Mf was found to be infrequent.
Cystic fibrosis transmembrane conductance regulator mediates sulphonylurea block of the inwardly rectifying K+ channel Kir6.1
Authors: Ishida‐Takahashi Ayako , Otani Hideo , Takahashi Chiaki , Washizuka Takashi , Tsuji Keiko , Noda Makoto , Horie Minoru , Sasayama Shigetake
Published: September 2010

Recombinant ATP‐sensitive K+ channels (KATP channels) were heterologously expressed in the NIH3T3 mouse cell line, and the electrophysiological properties were studied using patch‐clamp techniques.

The NIH3T3 cell lines transfected with the inwardly rectifying K+ channel Kir6.1 alone or with both Kir6.1 and cystic fibrosis transmembrane conductance regulator (CFTR) exhibited time‐independent K+ currents with weak inward rectification. In contrast, no measurable K+ conductance was observed in mock‐transfected cells or in cells transfected with CFTR alone. Regardless of co‐transfection with Kir6.1, the transfection with CFTR produced a Cl− conductance that was activated by cell dialysis with cAMP (1 mM). The conductance was reversibly suppressed by glibenclamide (30 μM).

Whole‐cell currents at +60 mV were blocked in a concentration‐dependent manner by Ba2+ ions with similar IC50 values: 89.3 ± 23.3 μM (Kir6.1 alone) and 67.3 ± 24.9 μM (Kir6.1‐CFTR).

The currents recorded from Kir6.1‐transfected cells were not affected by glibenclamide, whereas glibenclamide did inhibit the conductance expressed in cells co‐transfected with CFTR (IC50= 35.9 ± 6.6 μM).

In the cell‐attached mode with a 150 mM K+ pipette solution, both Kir6.1‐ and Kir6.1‐CFTR‐transfected cells displayed a class of K+ channels showing weak inward rectification and a slope conductance of 50.7 ± 1.0 and 52.4 ± 4.9 pS, respectively.

In the inside‐out mode, the single‐channel currents recorded from both types of cells were not inhibited by intracellular ATP (1 mM). However, glibenclamide was found to block the single‐channel activities in the co‐transfected cells.
Characterization of 5‐HT‐sensitive potassium conductances in neonatal rat facial motoneurones in vitro
Authors: Larkman P. M. , Kelly J. S.
Published: September 2010

The properties of the 5‐HT‐sensitive K+ conductance of neonatal rat facial motoneurones were examined in brainstem slices using whole‐cell patch‐clamp techniques.

In a small proportion of motoneurones, 5‐hydroxytryptamine (5‐HT) evoked an inward current mediated solely by a decrease in K+ conductance. The reversal potential (V5‐HT) was dependent on the external K+ concentration and the 5‐HT‐evoked current (I5‐HT) displayed a linear current‐voltage (I‐V) relationship.

In the remaining motoneurones, the 5‐HT‐evoked decrease in K+ conductance could only be observed in isolation once a concomitant 5‐HT‐mediated enhancement of the hyperpolarization‐activated current, Ih, had been abolished with the Ih blocker, ZD‐7288.

External Cs+ also abolished the Ih‐mediated component of I5‐HT but, in addition, blocked part of the 5‐HT‐sensitive K+ current. At potentials hyperpolarized to V5‐HT, Cs+ voltage dependently blocked I5‐HT while at potentials depolarized to V5‐HT, I5‐HT was largely unaffected. Ba2+ and Rb+ had identical actions to Cs+ on the 5‐HT‐sensitive K+ current.

The Ba2+‐, Rb+‐ and Cs+‐sensitive component of the 5‐HT‐sensitive K+ current inwardly rectified with a reversal potential that was dependent on the K+ equilibrium potential (EK).

Replacing external Na+ with N‐methyl‐D‐glucamine, blocking Ca2+ entry, or preventing an increase in intracellular [Ca2+] with BAPTA, all failed to alter I5‐HT at potentials depolarized to EK.

I
5‐HT at depolarized potentials was reversibly blocked by 4‐aminopyridine (4 mM) but not tetraethylammonium chloride (30 mM) and did not show inactivation during depolarizing voltage pulses (1.5 s duration).

The results suggest that, in addition to enhancing Ih, 5‐HT modulates two distinct K+ conductances in neonatal rat facial motoneurones. The actions of Cs+, Ba2+ and Rb+ support the involvement of a member of the inwardly rectifying family of K+ channels while the other K+ channel may belong to the voltage‐gated family.
Temperature‐dependent changes in the viscoelasticity of intact resting mammalian (rat) fast‐ and slow‐twitch muscle fibres
Authors: Mutungi G. , Ranatunga K. W.
Published: September 2010

The tension and sarcomere length responses induced by ramp stretches (at amplitudes of 1‐3 % fibre length (Lo) and speeds of 0.01‐12 Lo s−1) were examined at different temperatures (range, 10‐35 °C) in resting intact muscle fibre bundles isolated from the soleus (a slow‐twitch muscle) and extensor digitorum longus (a fast‐twitch muscle) of the rat. Some observations are also presented on the effects of chemical skinning on passive viscoelasticity at 10 °C.

As previously reported, the tension response to a ramp stretch, in different preparations and under various conditions, could be resolved into a viscous (P1), a viscoelastic (P2) and an elastic (P3) component and showed characteristic differences between slow and fast muscle fibres.

Chemical skinning of the muscle fibres led to a decrease in the amplitude of all three tension components. However, the fast‐slow fibre differences remained after skinning. For example, the viscosity coefficient derived from P1 tension data decreased from 0.84 ± 0.06 before skinning to 0.44 ± 0.06 kN s m−2 after skinning in fast fibres; the corresponding values in slow fibres were 2.1 ± 0.08 and 0.87 ± 0.09 kN s m−2, respectively.

Increasing the experimental temperature from 10 to 35 °C led to a decrease in all the tension components in both fast and slow muscle fibre bundles. The decrease of P1 (viscous) tension was such that the viscosity coefficient calculated using P1 data was reduced from 0.84 ± 0.1 to 0.43 ± 0.05 kN s m−2 in fast fibres and from 2.0 ± 0.1 to 1.0 ± 0.1 kN s m−2 in slow fibres (Q10 of ≈1.3 in both).

In both fast and slow muscle fibre preparations, the plateau tension of the viscoelastic component (P2) decreased by 60‐80 % as the temperature was increased from 10 to 35 °C giving P2 tension a Q10 of ≈1.4 in slow fibres and ≈1.7 in the fast fibres. Additionally, the relaxation time of the viscoelasticity decreased from 11.9 ± 1 ms (fast) and 43.1 ± 1 ms (slow) at 10 °C to 3 ± 0.5 ms (fast) at 25 °C and 8.7 ± 0.6 ms (slow) at 35 °C (Q10 of ≈2.0 in slow and ≈2.5 in fast fibres).

The fast‐slow fibre differences in passive viscoelasticity remained at the high physiological temperatures. The physiological significance of such fibre‐type differences and their possible underlying mechanisms are discussed.
Cardiac output distribution in response to hypoxia in the chick embryo in the second half of the incubation time
Authors: Mulder A. L. M. , van Golde J. C. , Prinzen F. W. , Blanco C. E.
Published: September 2010

The fetus develops cardiovascular adaptations to protect vital organs in situations such as hypoxia and asphyxia. These include bradycardia, increased systemic blood pressure and redistribution of the cardiac output. The extent to which they involve maternal or placenta influences is not known. The objective of the present work was to study the cardiac output distribution in response to hypoxia in the chick embryo, which is independent of the mother.

Fertilized eggs were studied at three incubation times (10‐13 days, 14‐16 days and 17‐19 days of a normal incubation time of 21 days). Eggs were placed in a Plexiglass box in which the oxygen concentration could be changed. Eggs were opened at the air cell and a chorioallantoic vein was catheterized. Cardiac output distribution was measured with 15 μm fluorescent microspheres injected during normoxia, during the last minute of a 5 min period of hypoxia and after 5 min of subsequent reoxygenation.

Hypoxia caused a redistribution of the cardiac output in favour of heart (+17 to +160 % of baseline) and brain (+21 to +57 % of baseline) at the expense of liver (‐3 to ‐65 % of baseline), yolk‐sac (‐46 to ‐77 % of baseline) and carcass (‐6 to ‐33 % of baseline).

The magnitude of the changes in cardiac output distribution to the heart, brain, liver and carcass in response to hypoxia increased with advancing incubation time.

The data demonstrate the development of a protective redistribution of the cardiac output in response to hypoxia in the chick embryo from day 10 of incubation.
Activation patterns of mono‐ and bi‐articular arm muscles as a function of force and movement direction of the wrist in humans
Authors: van Bolhuis B. M. , Gielen C. C. A. M. , van Ingen Schenau G. J.
Published: September 2010

In order to explain the task‐dependent activation of muscles, we have investigated the hypothesis that mono‐ and bi‐articular muscles have a different functional role in the control of multijoint movements. According to this hypothesis, bi‐articular muscles are activated in a way to control the direction of external force. The mono‐articular muscles are thought to be activated to contribute to joint torque mainly during shortening movements.

To investigate this hypothesis, surface electromyographic (EMG) recordings were obtained from several mono‐ and bi‐articular arm muscles during voluntary slow movements of the wrist in a horizontal plane against an external force. The direction of force produced at the wrist and the direction of movement of the wrist were varied independently.

The results revealed distinct differences between the activation patterns of mono‐ and bi‐articular muscles. The activation of the bi‐articular muscles was not affected by movement direction, but appeared to vary exclusively with the direction of force.

The mono‐articular muscles showed significantly more EMG activity for movements in a specific direction, which equalled the movement direction corresponding to the largest shortening velocity of the muscle. The EMG activity decreased gradually for movements in other directions. This direction‐dependent activation appeared to be independent of the direction of the external force.
PERCEPTUAL MODE AND CARDIAC CONDITIONING
Authors: Hein P. L. , Cohen Sanford I. , Shmavonian B. M.
Published: September 2010

Conditional heart rate responses were measured for field‐dependent and field‐independent subjects. The conditional stimulus (CS) was a colored light and the unconditional stimulus (US) was an electric shock delivered to the finger. The CS‐US interval was 10 sec. The field‐independent subjects demonstrated an initial cardiac acceleration followed by a cardiac deceleration, whereas the field‐dependent subjects showed only the cardiac deceleration. When these data are compared with the previously reported galvanic skin response (GSR) data, a model of sympathetic‐parasympathetic reactivity is evolved wherein the field‐independent group shows both conditioned sympathetic and parasympathetic autonomic activity, while the field‐dependent group shows only parasympathetic activity.
COMMENTS REGARDING MULTIPLE RESPONSE PHENOMENA IN LONG INTERSTIMULUS INTERVAL CONDITIONING
Authors: Lockhart Russell A.
Published: September 2010

When the CS‐US interval is longer than the latency of an autonomic response, multiple responses are obtained both during and after the CS‐US interval on acquisition test or extinction trials. Certain terminologic, methodologic and conceptual problems concerning this multiple response phenomenon are outlined. A nontheoretical and, we hope, unambiguous terminology is presented. Methodologic problems concerning multiple‐response measurement, between‐ and within‐ subject designs, trace and delay paradigms, intramodal and intermodal paradigms, and incompleteness of data presentation are discussed. It is felt that empirical analysis of the multiple response phenomenon will have important ramifications for our understanding of autonomic behavior in the classical conditioning situation.
THE ROLE OF THE PREPARATORY INTERVAL IN THE RELATIONSHIP BETWEEN EEG α‐BLOCKINGAND REACTION TIME
Authors: Thompson Larry W. , Botwinick Jack
Published: September 2010

The association between α‐blocking and improved reaction times (RTs) has not been consistently demonstrated in past studies. The possible importance of the preparatory interval (PI) in this relationship has not been totally assessed, and it was felt that further exploration of this variable would help to explain the discrepancies. RTs were measured in two experiments, each using different types of stimuli and different PI durations. In the first, 4 PIs, 0.5‐, 3.0‐, 6.0‐, and 15.0‐sec, were used in a regular and irregular series. The warning signal was a 400‐cps tone; the stimulus, a 1000‐cps tone. In the second. PIs were 0.50‐, 0.75‐, 1.00‐, and 1.50‐sec; the stimulus was a single flash from a photo stimulator. EEGs were recorded simultaneously from the parieto‐occipital region. Both peak‐to‐peak amplitude measures and subjective ratings of α‐activity were made prior to the onset of the warning signal and the stimulus. The results did not support earlier findings of a relationship between α‐blocking and RT. However, RT and α‐blocking were each (independently) a function of the PI.
A COMPARISON OF AC AND DC EYE MOVEMENT RECORDING
Authors: Tursky Bernard , O'Connell Donald N.
Published: September 2010

This study demonstrates the distortions introduced into the electro‐oculographic record as a function of choice of recorder time constant. Controlled waking eye movements were simultaneously recorded on five separate channels from the same pair of nonpolarizable Ag/AgCl electrodes. Time constants for these channels were DC, 3 sec, 1 sec, 0.3 sec, and 0.1 sec. Results indicate that eye movement recorded through short time constants cannot differentiate between rapid eye movement and saccadic components of slow eye movements, cannot follow slow smooth eye movements, and cannot show the position of the eyes when they are not in motion. The use of DC coupling makes it possible to record these three classes of events faithfully.
OPERANT CONDITIONING OF HEART RATE SLOWING
Authors: Engel Bernard T. , Hansen Stephen P.
Published: September 2010

The purpose of this study was to see if heart rate (HR) slowing could be operantly conditioned. Ten experimental Ss and five yoked‐control Ss were studied. Experimental Ss were positively reinforced for slowing their HR on a beat‐by‐beat basis, whereas yoked‐control Ss were reinforced in a pattern based on the performance of paired experimental Ss. The data showed that: some Ss can be taught to slow their HR by means of an operant conditioning procedure; Ss appear to learn better when they do not infer correctly what the response is that they are controlling; the conditioned HR response is apparently not mediated by changes in breathing; and reinforcement, per se, is not adequate to lower HR.
THE USE OF ELECTRO‐OCULOGRAPHY FOR IDENTIFYING PHASES OF COGNITIVE PROCESS
Authors: Rosen Sidney , Czech Donald
Published: September 2010

The present investigators were partly concerned with possible uses of electro‐oculography for studying the cognitive process in decision‐making situations involving nonneutral visual stimuli.

S was faced with receiving an electric shock if on critical trials he correctly reported (manually) the identity of the visual stimulus, or with escaping shock by incorrect reporting. Electrooculogram responses were ascertained to identify eye movements. The first study employed slit geometric figures as critical stimuli and nonslit figures as noncritical stimuli. The second study differed only in using blanks as critical and nonblanks (figures) as noncritical stimuli.

The 80 males in the first study showed longer ocular latency, then greater ocular avoidance (narrower excursions) but longer stimulus viewing, then longer poststimulus viewing on critical compared to noncritical trials. The 25 males in the second study showed relatively greater ocular latency, then greater ocular avoidance and briefer stimulus viewing, then briefer poststimulus viewing on critical trials. Discrepancies between the two studies were discussed.

The results clearly indicate the applicability of electrooculography for identifying phases of cognitive process.
DIFFERENTIAL CARDIAC RESPONSE TO VISUAL AND AUDITORY STIMULATION IN THE YOUNG CHILD
Authors: Lewis Michael , Spaulding Sara Jane
Published: September 2010

In this study, 24 infants, 6 months old, each received a series of visual and auditory stimuli. An analysis of their cardiac response indicates that onset of stimulus presentation results in a monophasic response of cardiac deceleration. Further, their response to onset of presentation was compared to their response to onset of visual orientation, and the data reveal that is it important for E to differentiate the cardiac response to presentation (E operation) from the onset of orientation (S operation). These results were used to explain the discrepancy between the cardiac responses of neonates and 6‐month‐old infants to stimulus presentation. (M. Lewis.)
NOCTURNAL EEG‐GSR PROFILES: THE INFLUENCE OF PRESLEEP STATES
Authors: Lester B. K. , Burch N. R. , Dossett R. C.
Published: September 2010

The number of nocturnal galvanic skin responses‐(GSRs) varied widely between the electroencephalograph (EEG) stages of sleep as well as from night to night and from person to person. As others have found, non‐specific GSRs occurred much more frequently during stage IV than other EEG stages, and were rare in stage REM. However, night‐to‐night variation and individual differences were related to the presleep state of the person. In general, electrodermal activity increased in all EEG stages as daytime stress increased, being especially great on nights preceding important school examinations.

The nocturnal EEG profile was also related to the presleep state, the percentage of stage IV decreasing as daytime stress increased. The percentage of stage REM showed no systematic relation to stress.

The occurrence of GSR “storms” during slow‐wave sleep is consistent with the notion of release of cortical or other inhibitory influences during this state, but another mechanism is needed to explain the fact that presleep stress increases the frequency of GSRs in all stages of sleep, while simultaneously decreasing the percentage of slow‐wave sleep.
RESPIRATORY CHANGES AT AUDITORY AND VISUAL THRESHOLDS
Authors: Rousey Clyde L. , Reitz Willard E.
Published: September 2010

Length of respiratory cycles was monitored while Ss were presented with (1) auditory and (2) visual stimuli varying in intensity. The phenomenon of greatest slowing in respiration occurring at the S's auditory threshold was demonstrated. However, no consistent relationship was demonstrated between length of the respiratory cycle and visual threshold.
ELEMENTARY FUNCTIONAL CORRELATES OF THE TRANSCEPHALIC DC CIRCUIT
Authors: Cowen Murray A.
Published: September 2010

A brief general theory is proposed linking the transcephalic DC potential, which is recorded on the midline surface of the head over the frontal and occipital emissary veins, with a certain functional organization of the brain. From this it is proposed that interoceptive or protopathic afferents—carotid sinus, carotid body, vestibular, and visceral—should produce a positive frontal deflection, while exteroceptive or epicritic afferents—tactile, auditory, proprioceptive, gustatory, visual, and olfactory—should produce a negative frontal DC shift. It is proposed that hunger promotes a negative frontal base line, satiety a positive one, and anxiety increases the base‐line variance of a group. A relationship is proposed between frontal negativity and body metabolic peaks. It is proposed that a noxious exteroceptive stimulus produces a positive frontal shift, despite its cortical projection. The hypotheses were tested using normal adult male Ss and good agreement between results and predictions was found.
PSYCHOPHYSIOLOGICAL ASPECTS OF PAROTID SALIVATION IN MAN: I. STIMULUS INTENSITY AND SALIVARY OUTPUT
Authors: Brown Clinton C. , Katz Ruth a.
Published: September 2010

This study was concerned with the relationship between stimulus intensity (concentration of citric acid) and parotid salivary response in man as reflected in four measures. Although this relationship varied with the measure employed, it was in no case linear. It was concluded that optimum concentration of citric acid for stimulating parotid salivary secretion in man was 1.0% and that the measure which differentiated best between the weakest acid stimulus and water as a control and between the two lowest concentrations of acid was the average quantity of evoked saliva per trial.
DIFFERENTIAL SENSITIVITY OF TWO PALMAR SWEAT MEASURES
Authors: McNair Douglas M. , Droppleman Leo F. , Pillard Richard C.
Published: September 2010

Two techniques for measuring palmar sweating were tested for their sensitivity to a standard anticholinergic agent. The finger sweat‐print and palmar sweatweight methods were compared in a double‐blind, crossover study by determining their relative sensitivity in detecting the antisweating effects of 0.5 mg of atropine sulfate. The sweat‐print method was significantly superior in detecting drug‐induced sweat reduction and hypothesized sex differences.
THE RELATION OF PALMAR SWEAT GLAND ACTIVITY TO LEVEL OF SKIN POTENTIALAND CONDUCTANCE
Authors: Venables P. H. , Martin Irene
Published: September 2010

The role of sweat gland activity in the mediation of skin potential and skin conductance levels was investigated. l‐Hyoscyamine was introduced into the fingertips by iontophoresis to eliminate sweat gland activity, and d‐hyoscyamine, an inert analog of the l‐isomer, was used as a control for ion size. Neostigmine was used to potentiate sweating. l‐Hyoscyamine significantly decreased skin conductance level and the number of active sweat glands and reduced the negativity of skin potential level, but neostigmine, which promoted sweating and skin conductance, did not increase the negativity of skin potential. The lowering of skin potential on the denervated hand of a hemi‐sympathectomized patient was found to be similar in magnitude to the decrease in skin potential due to pharmacological elimination of sweat gland activity. The results are discussed in relation to hypotheses concerning the mechanism of skin potential.
THE ROLE OF “LYING” IN PSYCHOPHYSIOLOGICAL DETECTION
Authors: Kugelmass Sol , Lieblich Israel , Bergman Zeev
Published: September 2010

An experiment was designed to examine the role of lying behavior, per se, as the basis for experimental psychophysiological detection of deception. In addition to the standard card‐test procedure, a second procedure required the S to say “yes” to every question posed relating to the card chosen. This variation involved telling the “truth” in respect to the critical card in contrast to the usual procedure in which he is required to “lie.” With the use of the galvanic skin response (GSR)channel, significant detection rates were obtained for both procedures with nosignificant difference between them. Some theoretical issues related to the findings were explored.
AN INEXPENSIVE LEVEL DETECTOR
Authors: Swinnen Maurice E. T.
Published: September 2010

A solid‐state Schmitt trigger has been designed with the aim of providing reliable triggering at ± 5 v on any input waveform. Input impedance is high; hysteresis, rise and fall times, and circuit delay are extremely short. Power consumption is small. Power supply ripple and instability are eliminated by the use of a battery power pack. Construction time, cost, and technical difficulties are reduced with a solid‐state encapsulated module.
Affective Response to Color‐Slide Stimuli in Subjects with Physical Anhedonia: A Three‐Systems Analysis
Authors: Fitzgibbons Lee , Simons Robert F.
Published: September 2010

Emotion‐provoking visual stimuli were presented to college undergraduates identified as anhe‐donic or normal, based on their scores on the Physical Anhedonia Scale (Chapman, Chapman, & Raulin, 1976). The affective stimuli (35 mm color slides) were chosen to elicit a wide range of both positive and negative emotion, with emotional response assessed through affective judgments, viewing time, and monitoring of a variety of physiological systems (heart rate, skin conductance, and facial musculature). The experiment was successful in demonstrating differential emotional response in the two subject groups; anhedonic subjects reported a less positive response than control subjects to positive and neutral stimuli and showed no association between heart rate and the emotion content of the slides. Paradoxically, activity in the muscles of facial expression was greater in anhedonic than control subjects during the presentation of both positive and negative slides. No between‐group differences were noted in the viewing‐time measure. The results are discussed in the context of Lang's bioinformational theory of human emotion (Lang, 1984, 1985).
Taking Attention to Task: P300, Task Response Probability, and Within‐Category Deviation Detection
Authors: Nasman Victoria Tepe , Rosenfeld J. Peter
Published: September 2010

Previously, we reported enhanced P3 amplitudes to between‐category deviations among high and low probability events. Here, we tested the effects of a within‐category difference. Subjects performed a go/no‐go button press task as they viewed repeated, randomly‐ordered presentations of nine double‐digit numbers. Eight numbers fell within a prescribed range (42–49, standards); prior to testing, subjects selected one standard number for later recall. A ninth, out‐of‐range (91, deviant) number was also included. Subjects were tested under two conditions, in which they responded either to one (low response probability) or to seven (high response probability) standard nonselected numbers, designated as targets. Relatively larger P3s were consistently apparent only when the deviant nontarget was associated with a low probability response to a nontarget. There was a selective effect of nontarget response probability on P3 amplitude to the deviant nontarget. Our results indicate that within‐category deviation detection is facilitated by “controlled”attention to the structure of the stimulus field.
Word Frequency and Multiple Repetition as Determinants of the Modulation of Event‐Related Potentials in a Semantic Classification Task
Authors: Young Malcolm P. , Rugg Michael D.
Published: September 2010

We recorded event‐related potentials while subjects performed a category membership decision task. The stimuli were words of high and low frequency of occurrence in written English, and each was presented four times. The experiment was intended to explore the interaction of word frequency and multiple repetition on the event‐related potential, and thence to investigate the possible loci in time of the effects of these variables. First presentations of low and high frequency words evoked event‐related potentials which differed in the presence, in the low word frequency waveforms, of a right‐hemisphere dominant negativity peaking at 400 ms. This negativity was very similar to the N400 which may be sensitive to the semantic relations among words in a sequence. Initial repetition diminished this midlatency difference, but gave rise to both earlier and later frequency‐related differences. Subsequent multiple repetition abolished the early frequency‐related repetition effect, but did not affect amplitudes in the region of N400, nor did it abolish a late positivity, present only for repeated low frequency words.
Aerobic Fitness and Opioidergic Inhibition of Cardiovascular Stress Reactivity
Authors: McCubbin James A. , Cheung Robyn , Montgomery Thomas B. , Bulbulian Ronald , Wilson John F.
Published: September 2010

The role of endogenous opioids in aerobic fitness‐induced decrements in cardiovascular stress reactivity was examined by comparing the effects of opioid antagonism with naltrexone on responses to stress in young adults with high versus low levels of aerobic fitness. Two hundred forty subjects were given an activity questionnaire and males with the highest (Fit) and lowest (Nonfit) aerobic activity profiles were recruited for maximal oxygen consumption (Vo2max) treadmill testing and psychological stress testing (final sample N=28). Heart rate and blood pressures were measured during performance on a computer‐controlled arithmetic task after pretreatment with either naltrexone (Trexan, DuPont) or a placebo. During placebo challenges, Fit subjects, compared with Nonfit, showed lower heart rate reactivity during stress and lower mean arterial blood pressures immediately before and during recovery from stress. Naltrexone eliminated these reactivity differences by increasing heart rate reactivity and raising mean arterial blood pressure in Fit subjects. These data suggest that aerobic fitness is associated with enhanced opioidergic inhibition of circulatory stress reactivity. Opioidergic modulatory effects on stress reactivity may comprise an important mechanism in fitness‐associated risk reduction for cardiovascular disease.
Alternate Cardiovascular Baseline Assessment Techniques: Vanilla or Resting Baseline
Authors: Jennings J. Richard , Kamarck Thomas , Stewart Christopher , Eddy Michael , Johnson Paul
Published: September 2010

The accurate evaluation of cardiovascular reactions to psychological challenge requires stable baselines against which change can be evaluated. When more than one challenge is employed, the recovery of this baseline becomes important in order to avoid carryover effects. Resting periods, even those of 20 min or more, do not guarantee baseline stability. We compared a 20‐min resting condition and a new form of baseline condition in 48 college men using video tasks as the psychological challenges. The new form was a minimally demanding color detection task, termed the “vanilla”baseline condition. A 10‐min version and a 20‐min version of this condition were tested. Comparisons to 10‐min resting baselines were made using our prior work and values from the literature. Vanilla baseline conditions were shown to be equal to or better than resting baseline conditions using criteria of between‐ and within‐baseline stability, amplitude and significance of responsivity, and generalizability between sessions on separate days. Ten‐minute resting baselines also showed acceptable stability, questioning the value of lengthy baselines. The good performance of the 10‐min vanilla baseline in initial and replication samples supported its utility for estimating baselines for many purposes.
Predicting ambulatory blood pressure during school: Effectiveness of social and nonsocial reactivity tasks in black and white adolescents
Authors: EWART CRAIG K. , KOLODNER KENNETH B.
Published: September 2010

We evaluated a newly developed stress task, the Social Competence Interview, and three nonsocial tasks (video game, mirror drawing, mental arithmetic) for ability to predict ambulatory blood pressure in 237 black and white adolescents. Blood pressure was measured in laboratory, classroom, and transition (between‐class) settings. A resting laboratory baseline explained 10–49% of the variance in ambulatory blood pressure levels; the ability of the stress tasks to explain additional variance was assessed in multiple regression analyses. Only the blood pressure response to the interview enhanced prediction of classroom and transition systolic and diastolic pressures in the total sample and in blacks, whites, females, and males – even when the interview data were entered into a hierarchical regression model after those for the other three tasks were entered. Mirror drawing improved prediction of transition systolic blood pressure in the total sample, and mental arithmetic plus the interview improved prediction of classroom diastolic pressure in black males; however, video game failed to enter any predictive equation. Racial subgroup analyses disclosed that the interview data predicted systolic pressure in whites but predicted diastolic pressure in blacks, indicating biological differences in blood pressure regulation. An interview that elicits characteristic thoughts and social behaviors appears to represent a promising approach to examining environmental influences on blood pressure.
Patterns and stability of cardiovascular responses to variations of the cold pressor test
Authors: DUREL LYNN A. , KUS LISA A. , ANDERSON NORMAN B. , McNEILLY MAYA , LLABRE MARIA M. , SPITZER SUSAN , SAAB PATRICE G. , EFLAND JAY , WILLIAMS REDFORD , SCHNEIDERMAN NEIL
Published: September 2010

Test‐retest reliabilities and patterns of heart rate and blood pressure responses were examined using variations in the cold pressor test in 113 normotensive white college men. Comparisons were made of stimulus site (forehead vs. foot) and bodily posture (seated vs. supine) across four separate groups of men. The stability of cardiovascular responses was examined over a 2‐week test‐retest interval. Different cardiovascular response patterns emerged as a function of stimulation site and posture. Systolic and diastolic blood pressure increases were accompanied by bradycardia in the forehead cold pressor task but by tachycardia in the foot cold pressor task. Systolic blood pressure increases were larger for foot than for forehead stimulation. Heart rate increases were larger for supine than for seated men. Effects on response were independent of postural differences at baseline, and there were no stimulation site by posture interactions. The cardiovascular responses to stimulation did not attenuate across sessions in any experimental condition but were more reliable for foot than for forehead stimulation and for supine than for seated posture. Short‐term stability for changes to the task approached that for baseline and task and was higher than has been reported elsewhere.