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Slow potential changes were recorded from the scalp of ten adult subjects during performance of a disjunctive reaction task. Tones separated by a constant 1.0 sec interval were employed for the conditional and imperative stimuli. The subject was instructed to execute or withhold a digital response, depending upon the frequency of the imperative stimulus. Motivational state was manipulated by two different sets of instructions. 1. 1. Contingent negative variations (CNVs) were obtained in all subjects under conditions of both high and low motivation. 2. 2. In a majority of subjects performing with closed eyes, potentials originating from the eyes were seen to contaminate activity recorded from the vertex. This problem was not encountered in subjects who had their eyes open and fixated. 3. 3. Within subjects, the fastest reaction times were preceded by CNVs of significantly larger amplitude than were the slowest responses. A comparable relationship was not found between subjects. 4. 4. Reaction times were shorter, and the negative evoked potential to the warning stimulus had a significantly greater amplitude when the subjects were in a state of high motivation than when they were urged to relax. Other potentials, including the CNV, did not show this difference between motivational conditions. 5. 5. Trials in which subjects were required to respond were followed by a broad positive wave of moderate amplitude, whereas trials in which they withheld a response were followed by a short positive wave of much greater amplitude. The height of both potentials was significantly correlated with mean reaction time across subjects.

In six persons with spontaneous vertical nystagmus behind closed eyes, concurrent horizontal nystagmus was induced by caloric irrigation of the horizontal semicircular canals in the vertical position. This procedure caused no change in the vertical nystagmus pattern. When the horizontal nystagmus subsided, the number of eye movements decreased, whereas the vertical nystagmus continued unchanged. The rapid phases of horizontal and vertical nystagmus invariably coincided even if the two types otherwise differed in frequency.The mechanism eliciting nystagmus is discussed, the following conclusions being drawn: (1) the slow phase of horizontal and vertical nystagmus is controlled from separate independent centers; (2) the rate of the slow phase is influenced by both peripheral and central factors; (3) the rapid phase is elicited from a center common to horizontal and vertical nystagmus; (4) the mechanism of nystagmus is controlled from the extraocular muscle nuclei but may be affected by various centers.

Aim: This study aims to evaluate and identify the influence of age, sex, and visual information on postural control in children. Methods: Participants were 62 children (30 boys and 32 girls) divided into the following age groups (G): G1, aged 5-6 years (n = 23); G2, aged 7-8 years (n = 21); and G3, aged 9-10 years (n = 18). The analyzed variables were the center of pressure (COP) and anteroposterior (AP) and mid-lateral (ML) oscillation velocity (OV) obtained in the biped posture force platform with their open eyes (OE) and closed eyes (CE). Results: G3 COP, OV_AP, and OV_ML are smaller than those in G1 and G2 in OE (p < 0.00) and CE (p < 0.05). Girls demonstrated worse postural control than boys for COP, OV_AP, and OV_ML (p < 0.00) in G1. Conclusion: Age was the most influential factor of COP (21%), OV_AP (24%), and OV_ML (39%). Older children perform better, because of the positive contribution of visual information. Girls initially had worse postural control responses, but at age 7-8, they tend to outgrow boys. Advanced age provides more influence on postural control than visual information and sex.

The relative roles of different receptor systems in compensating for vestibular loss were studied in 18 children (12 to 16 years of age) with congenital or early acquired bilateral vestibular loss (BVL) and impaired hearing, and compared to that in 33 normal children (9 to 16 years of age). Postural stability was studied with posturography evaluating the velocity of anterior-posterior body sway. With closed eyes the increase of sway velocity did not differ between the groups, either with or without simultaneous proprioceptive disturbances when the subjects were standing on a bare surface. Body sway velocities were found to increase more in subjects with a BVL than in normal children when subjects were standing on foam rubber. When proprioceptive cues were disturbed, body sway velocities increased in both groups, but significantly more in children with BVL when subjects stood on foam rubber. This occurred both with and without open eyes.

Objective: Primary orthostatic tremor is a rare neurologic condition of unknown origin characterized by a 10- to 20-Hz tremor in the legs while standing. Patients with primary orthostatic tremor usually complain of dizziness and unsteadiness that is relieved if they sit down or start to walk around. These patients might be referred to neurotology clinics. Previously, the only way to make the diagnosis has been by means of surface electromyographic recordings from the lower limbs during standing. The authors wanted to study whether posturography can be used to screen for primary orthostatic tremor. Study Design: Retrospective case review. Setting: Balance clinic at a tertiary referral center. Patients: From September 2000 to August 2002, 701 patients were investigated at the authors' balance clinic. Intervention: Static posturography on a force platform with 50-Hz sampling frequency. Recordings were made during 120 seconds of quiescent stance with open or closed eyes. Main Outcome Measure: Fast-Fourier transformation (FFT) analysis of recorded torque in the fore-to-aft direction to quantify the spectral power distribution in the range of 0 to 25 Hz. Visual inspection of power spectrum plots was performed. Results: Five patients (0.7%) were identified (1 man and 4 women; mean age, 56 yr; age range, 36-73 yr) with narrow peaks at 8.5 to 18 Hz in the power spectra of their posturographic recordings. Surface electromyographic recordings during standing confirmed their diagnosis of primary orthostatic tremor. Conclusion: Analysis of power spectra from posturographic recordings is a simple, quick method to screen for primary orthostatic tremor. The condition might be more common than previously assumed. It is important to identify patients with primary orthostatic tremor because they might be misdiagnosed and left without treatment.

Although adolescent spinal pain increases the risk for chronic back pain in adulthood, most adolescents can be regarded as healthy. The aim of the present study was to provide data on localization, intensity and frequency of adolescent spinal pain and to investigate which physical and psycho-social parameters predict these pain characteristics. On the occasion of Spine Day, an annual event where children and adolescents are examined by chiropractors on a voluntary basis for back problems, 412 adolescents (10 to 16 years) were tested (by questionnaire and physical examination). Pain characteristics (localization, intensity, and frequency) were identified and evaluated using descriptive statistics. Regression analyses were performed to investigate possible influencing psycho-social and physical influence factors. Adolescents who suffered from pain in more than one spinal area reported higher pain intensity and frequency than those with pain in only one spinal area. Sleep disorders were a significant predictor for pain in more than one spinal area (p

IntroductionArithmetic reportedly involves left parietal areas.ObjectivesTo test this in independent groups of healthy persons.AimsWhich brain regions are activated / inhibited during mental arithmetic compared to task-free resting?MethodsWe examined four independent groups of healthy adults (N = 15, 14, 14, 23, respectively) during simple arithmetic (continuous subtraction of 7) and task-free resting before and after arithmetic, all with closed eyes. Multichannel head surface EEG (19–58 channels) was continually recorded, then recomputed (using sLORETA functional tomography) into current density for 6239 cortical voxels, for each of the eight EEG frequency bands (delta through gamma, 1.5–44 Hz). Pre- and post-arithmetic resting was averaged. Using paired t-tests, frequency band-wise normalized and log-transformed current density was compared between arithmetic and resting for each group. The resulting p-values were combined across groups using Fisher’s combination procedure. For each frequency band, sLORETA voxels differing between conditions at Fisher’s (across groups) p < 0.05 were computed into centers of gravity separately for increased and decreased activation.ResultsActivity that was stronger during arithmetic compared to resting had gravity centers in midline anterior regions for slow frequency bands (delta, theta, alpha-1) and in right posterior regions for fast frequency bands (alpha-2 through gamma). Activity that was weaker during arithmetic compared to resting was centered around left parietal areas for all eight frequency bands.ConclusionsThe results suggest that arithmetic compared to resting involves frontal inhibition coupled with increased right parietal activation, and left parietal reduced facilitatory and reduced inhibitory activity.

The Drowsiness is the risk to fall asleep for one moment with the closed eyes, it is an intermediate state between the awake and the sleep. This state is involuntary and it is accompanied by a fall of vigilance. Consequently, the development of a system for the automatic control of driver tiredness, to prevent the driver in advance of the accidents, received an interest growing of research mediums. In this work, we propose an approache of drowsiness detection which makes it possible to determine the 3D head orientation to capture the lack of concentration states. This approach is based on the estimate of the head rotation angles in the three directions Y aw, Pitch and Roll by exploiting only three interest points of the face. The approache suggested are evaluated by the MiraclHB database. The evaluation show many promising results and show the effectiveness of the approache suggested.

A simple and effective method of recognizing eye blinking in industrial conditions is presented. The developed method uses a camera built into safety glasses. The presented algorithm can be applied to recognize whether glasses are correctly put on – to check if employees use personal protective equipment. Recognition of open or closed eyes allows control by intentional winking. The algorithm uses only light sources present in the workplace and does not require infrared radiation (IR). The solution was tested on a set of 1797 eye photos recorded in a group of 10 participants. An analysis of the correctness of blink recognition and the correctness of the algorithm's operation in various lighting conditions was carried out. Experiments showed that the proposed algorithm met required project assumptions. The averaged results of blink recognition obtained using the developed method are: accuracy 96.5%, precision 93.8%, specificity 98.9% and sensitivity 84.9%. Additionally the algorithm is insensitive to changes in lighting and allows the use of one type of glasses for different employees.

The effects of subanesthetic (21%) nitrous oxide (N2O) narcosis on postural control, as measured by posturography were studied in 12 subjects. Vibration induced body sway, with open and closed eyes, and body sway induced by a visual stimulus were evaluated. Adaptation was measured as the quotient of body sway variance between the second and first halves of each trial. Change in postural strategy was evaluated as change in the variance of shear forces relative to change in body sway. Subjective evaluation of narcosis was recorded. Body sway variance increased significantly during exposure to N2O, and equally for all body sway inducing stimuli. With tbe eyes open, adaptation to vibratory perturbation was significantly reduced by N2O. Postural strategy was unaffected by N2O, but differed significantly between stimuli, with relatively less involvement of shear forces during vibratory perturbation in the eyes open condition than during the other body sway inducing stimuli. Subjective evaluation of narcosis correlated with body sway variance during the visual stimulus. The present findings indicate that subanesthetic N2O narcosis reduces postural control. Adaptation to a balance disturbing stimulus, with undisturbed vision, is decreased by N2O. Visual clues are shown to be crucial to the postural strategy adopted to maintain balance. The effects of N2O are assumed to be due to impairment of sensorimotor integration in the CNS.

Standing ability seems to be one of the functions which show the most distinct decline in the process of aging. Yamamoto (1979) suggested that postural sway in natural standing increases after the age of fifties especially when eyes are closed. A steep decline by age is shown of the ability to sustain standing on one foot and with eyes closed (Meshizuka et al. 1975). There is thus possibility that such severe condition reveals some changes with age in the postural control system which do not appear in normal conditions. Many studies have been made on postural sway by means of spectral analysis (Taguchi, 1978, Chiwata, 1976, Sato, 1977). Frequency components of postural sway in normal subjects may give some information about changes in postural mechanisms by aging especially for one foot and closed eyes condition. This report deals with technical aspects of spectral analysis of postural sway in such conditions.

One hundred and twenty subjects were selected from a large number of healthy persons on the grounds of their medical history and preexaminations including audiogram, which excluded the possibility of a previous cochleo-vestibular illness. These 120 healthy persons were examined by means of electronystagmography. We were searching for spontaneous and positional nystagmus in 5 positions with open eyes in darkness and with closed eyes.

Thirty-four male Ss made size and distance estimates of an after-image observed with closed eyes. Size estimates showed small variability, but distance estimates were highly inconsistent. To account for the consistent size estimates it is tentatively proposed that although the subjective impression is of boundless space, with eyes closed the sensory system acts as if the eyes are fixated at a finite rather than infinite distance.

THE use of the cross as a sacred symbol dates from the earliest times, and is almost universal. It occurs upon the monuments and utensils of every primitive people from China to Yucatan. In many, perhaps in a majority of, instances it is used as a symbol of the sun. One of the oldest and most widely occurring forms is the cross with crampons turned to the right or left, the svastika and sauvastika of India, the “Thor's hammer” of Western Europe. Prof. Max Muller thinks that the svastika represents the vernal sun, and is hence an emblem of life, health, and creative energy (Schliemann's “Ilios,” p. 348). Mr. Edward Thomas (ibid.) believes it to have arisen from the conception of the sun as a rolling wheel. The Chaldean sun symbol was first a circle, then a circle with an inscribed cross. The symbol of the sun-god at Sippara is a small circle with four triangular rays, the four angles between being occupied by radiating lines, and the whole circumscribed by a larger circle. The same symbol occurs repeatedly upon the shell gorgets of the mound-builders (Second Annual Report of the U. S. Bureau of Ethnology, plates liii., lviii., and lix.). The peculiar figure repeated upon the facade of the “House of the Nuns” at Uxmal seems to be a conventionalised circle and cross with rays. The Moqui symbol for the sun is a Greek cross with a small circle at the centre, in which are three marks to indicate the eyes and mouth of a face (First Annual Report of the U. S. Bureau of Ethnology, p. 371). It is needless to multiply examples: the important question is, How has the cross come to be a symbol of the sun? If anyone will observe carefully a lamp, or other bright light, with partially closed eyes, the answer will be obvious. The rays which appear to proceed from the luminous point always form a cross of some kind. A little experimenting will show that this appearance is due to reflection from the eyelashes and edges of the eyelids. The same experiment may be tried with the sun itself: if observed when considerably above the horizon, squinting will be unavoidable. If the head is erect, the downward arm of the cross will be much the strongest, and the upward arm may be obsolete; but if the head is thrown back, the arms will be nearly equal. The evolution of the sun symbol seems to have been as follows: He was first represented by a circle or disk as he appears when near the horizon; observations made when he was shining brightly revealed the crossed rays. This led to a combination of the circle and cross. If this hypothesis be correct, the svastika was originally neither a rolling wheel, nor, as Burnouf supposes, the crossed sticks from which our ancestors elicited fire; but it is a modification of the circle and inscribed cross.

SEVERAL of the pioneer workers in rontgenology—Rontgen included—recorded the fact that X-rays are perceived by the dark-adapted eye. Similar observations were made on radium rays, which were even held to surpass ordinary light as a source of illumination to the partially blind: radium rays were in fact used by one observer1 for teaching at a blind school. Conflicting reports rapidly led to loss of all interest in the matter, until Taft2 in 1932 clearly established the visibility of X-rays, and Pirie3 simultaneously and independently directed attention to the possibility of 'reading with closed eyes' by means of X-ray light.

On 4 April 1981, five Geomys bursarius were livetrapped in Ellis County, Kansas (1? mi E Ellis, T.13S, R.20W, NE?4 Sec. 10), for use in breeding experiments under laboratory conditions. Three of these pocket gophers became debilitated and died after being kept in the laboratory for periods ranging from two to five days. Symptoms included restricted movement, loss of coordination, gasping for breath, and closed eyes. One gopher that was near death was sacrificed and autopsied aseptically. Heart, lung, liver, and intestinal tissues were placed in sterile petri dishes and sampled with Culturettes (Marion Scientific Collection System). Selective and differential media were inoculated and incubated at 35?C for approximately 24 hours. Klebsiella pneumoniae was recovered in all samples, indicating a bacteremia, and cause of death was attributed to pneumonia. Klebsiella pneumoniae can be a normal constituent of the flora of the respiratory system and intestinal tract and can become pathogenic after stress. Gophers collected subsequent to the diagnosis were orally administered 1cc sodium sulfathiazol (Isolite) in a solution of 0.26 gram per ounce of water. All cages were cleaned thoroughly and soil that was placed into the cages was baked for 2 hours at 176'C. No further losses of animals occurred as a result of pneumonia. We know of no published statements regarding the occurrence of pneumonia in fossorial mammals in general or in pocket gophers in particular. The plains pocket gopher appears to be extremely susceptible to pneumonia. Accordingly, pocket gophers no longer needed in captivity and having symptoms similar to ones previously mentioned probably should not be released into natural populations.

In the preceding numbers of this JOURNAL, the writer together with one of his students set forth the results of an investigation on the apparent distance of the negative after-image in the field of the closed eyes. Up to the time of printing, the writers had found no material bearing on the topic save casual references by Fechner and Hering. The fated article which, of course, had a Teutonic existence somewhere, has turned up in v. Graefe's Archiv for 1885 with Dr. G. Mayerhausen as sponsor and as title "Ueber die Gr6ssenverhdiltnisse der Nachbilder bei geschlossenen Lidern" (Abteilung 2 S. 23-24). The results differ so widely from those published in the JOURNAL as to call either for explanation or discussion or both. Experimenting on himself, Mayerhausen finds that the negative afterimage in the darkened field appears as large as the inducing object when the latter is set at a distance of two meters. In the case of the Stanford observers, three in number, unacquainted with each other's findings, the region of equality lay inside of eighteen centimeters from the cyclopean eye. Mayerhausen's method was as follows: As inducing objects he used four white discs, 1, 2, 4, and 8 cm. in diameter respectively, and developed after-images from them at ten different distances from the eye, beginning with five meters and running down to io cm. When the after-image was at its maximum clearness, he opened his eyes and compared its diameter with the readings of a centimeter scale held in his hand. In this way, he made eighty readings, viz., two for each size after-image at each of the ten distances. The writer humbly submits that this is a less trustworthy procedure than that described in the JOURNAL where the after-image with closed eyes was compared with the image projected on an adjustable screen until a region was found where the two images showed no appreciable difference. Within this region, after-images were induced and their size measured by projecting them on a ruled screen. The equating of the two forms of after-image was almost as accurate as if the images had been actual cardboard disks, successively compared. The estimation of the projected image was harder but nevertheless the size of the mean variation of the readings (from 4% to 10%) for the three observers showed that the judgments were based on actual if rough measurement.

IN a letter in NATURE of March 17, 1923, Mr. Gheury de Bray described some observations on time relations in a dream. He mentioned that hypnopompic (or hypnostrophic) images “are generally landscapes passing slowly before one's closed eyes, when in an almost awake condition … and having one's full reasoning powers while the illusion proceeds”. It seemed “that the speed of succession of the images is an inverse function of the degree of wakefulness”. A recent experience would tend to confirm these observations. A succession of faintly coloured landscape images was followed by a less ephemeral and apparently more vivid landscape, while there intruded, at first faintly, then more distinctly, sounds which became identified as knocking on the door. In the dream, the image (a well-known landscape) appeared as if the observer were in a vertical position. But after (? during) the disturbing sounds, an awareness of the actual (i.e. horizontal) position of the observer resulted in a conformable orientation of the image. As the observer was lying on his right side, the image seemed to have rotated 90° to the right, and thus the same relative position of observer and image, and also the continuity of the dream, were apparently preserved until completion of the wakening process.

To the Editor: —A perusal of Dr. Tieken's article in Hygeia on poison ivy and its treatment causes me to give my experience with the poisonous sumacs and their treatment. I have found melted wax to afford instant relief from pain, burning and itching in young and old, even with severe involvement of the rectal and vaginal mucosa. The course of the dermatitis is much shortened. A simple and easy method is to use a small swab with cotton and paint the parts with the melted wax. There is no danger, of course, from burning. With closed eyes the whole face may be painted. The least entrance of air beneath the mask or cast of wax necessitates sealing in the weakened part. I know from personal experience the instant relief from pain, burning and itching and the return of sleep which is so grateful to the patient, to say nothing

I. Its Etiology. We have read that a child's education ought to be started before its birth; and, in our opinion, the consideration of strabismus is incomplete unless we remember that the ancestral history of these cases often contains an account of one or more persons where the visual line of one eye deviated from the object looked at with the other eye. Such predisposition undoubtedly tends to the production of squint in the offspring. The young of all animals remain with closed eyes for a variable period after birth. The human offspring is no exception. Whether this is due to a sudden change from darkness to light, or because the retinal functional development is inadequate for useful purposes, or because the brain itself is dormant, or because of all these several conditions combined, is unknown. The baby automaton has not yet awoke to the necessities of vision. Its functions

The drug mescaline 1 has a peculiar influence on the central nervous system of man. 2 Within a brief time after its introduction into the organism it causes a clearcut disorder. The most characteristic symptoms are visual phenomena. The subject sees, with closed eyes, with open eyes in a dark room or against the background of a screen, a wealth of visons characterized by lavish colors and more or less geometric forms, all of which are in perpetual movement. Among other symptoms, some of which are remarkably constant and occur in practically every case, are: a general passive attitude; a surprising disorientation as to the time that elapses during the experiment; a tendency to observe tiny details in the immediate environment, such as beginning fine cracks in the wall; an increased sensitiveness and attention to all colors in the environment; a feeling that the whole body is "lighter"; a pleasant

Kleitman (4) has suggested that the frequency of the alpha EEG partern is related to level of consciousness. He presented studies which showed a decrease in alpha frequency during sensory isolation, an increase in alpha frequency in hyperthermia, a decrease in alpha frequency associated with hypothyroidism, and an association of alpha frequency and body temperature within the individual. Other evidence has suggested that the level of consciousness is related to the variability of the amplitude of the EEG (1, 2, 3, 5, 6). To investigate possible association of alpha frequency and amplitude variation of the normal EEG in a wakeful state was the aim of this study. The EEGs of 50 paid normal males (ages 17 to 62, inclusive), about high school educational level, were individually recorded. Each recording session was of 15 min. duration and held in a sound attenuated room with S in a supine position with closed eyes. A solidstate integrator and a Beckman-Offner Type R Polygraph were used to record the EEG from