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has been and is still [Adrian (1)] dominated by certain concepts which have proved so convenient that they have come to be accepted without serious question by the majority of physiologists and by many psychologists. These concepts are Muller's so-called "law" of specific nervous energies, and von Frey's extrapolation of this law into the theory of punctate representation of primary sensory modalities. In other words, it is commonly accepted that there are mo;phologically specific pai n, warmth, cold, and touch nerve end­ ings, specific nerve fibres, and specific nerve pathways. It is for this reason that so much emphasis has been laid on the analysis of somesthesis and the chemical senses in terms of the activity of single nerve fibres, which has resulted in reviews that consist of collat ions of literature reporting the results of e1ectrophysiolog ical experiments. Recent anatomical and psycho-physio logical work, however, has seri­ ously challenged the validity of Muller's law and von Frey's theory with re­ gard to cutaneous sensibility, and has made it necessary to re-examine all the experimental observations on the sensory nervous system from a wholly different point of view. This revieJ.V will, therefore, take a somewhat unconventional form. In the first place, we shall examine and collate the evidence which seeks to refute the accepted concepts and then, in the light of these new observations, ex­ amine some of the literature in the field of somesthesis which has appeared in the course of the past year. The literature on the chemical senses was ably reviewed in Volume 5 of the Annual Review of Psychology and for this reason has been dealt with less exhaustively on this occasion. The review is intended to be provocative and critical, and necessarily reflects the author's personal opinion of the evidence before him. SOMESTHESIS Recent observations on the mechanism of cutaneous sensibility.- The state­ ments which follow are based on a series of publications by Weddell and his co-workers (2 to 21) , some of which appeared before 1953. Reference should be made to all of these publications if exhau stive examination of the evi­ dence is desired. Neurohistologica l

The treatment of auricular fibrillation and flutter by the administration of quinidin sulphate is attracting much attention. In order to establish the correct status of this drug in the therapy of these arrhythmias, it is essential that publicity be given to untoward effects as well as to successes. A single instance of respiratory paralysis has occurred in the use of quinidin sulphate in the wards of the Boston City Hospital. Many fatalities have been reported following the administration of quinidin. Most of these have been attributed to embolism, and, for a few, the explanation of cardiac standstill, associated with heart block, has been given. Apparently, the occurrence of paralysis of respiration is rare. Von Frey, 1 who introduced quinidin in cardiac therapy, has recorded two cases in his second report, 1 and, more recently, a third was described by him and Hagemann. 2 One of Haass' 3 patients, who had

Summary The question of lateral differences in tactile sensitivity among normal persons has been the subject of a number of recent studies. These studies, in which thresholds for tactile pressure were determined by the von Frey method, have yielded inconsistent results; some have reported higher sensitivity of the left side while others have found no lateral differences. The results of one study has suggested the possibility of an association between handedness and lateral differences in tactile sensitivity. The present study reinvestigated the question through the use of an electromechanical tactile stimulator permitting independent control of the stimulus variables of pressure and area. No right-left differences were found, either with stimulation of the palms of the hands or the backs of the hands. A second experiment, in which thresholds for sharpness were investigated, also failed to disclose right-left differences. Nor were any correlations found between handedness and thresholds for pressure or for sharpness.

Measuring inflammation-induced changes in thresholds of hind paw withdrawal from mechanical pressure is a useful technique to assess changes in pain perception in rodents. Withdrawal thresholds can be measured first at baseline and then following drug, venom, injury, allergen, or otherwise evoked inflammation by applying an accurate force on very specific areas of the skin. An electronic von Frey apparatus allows precise assessment of mouse hind paw withdrawal thresholds that are not limited by the available filament sizes in contrast to classical von Frey measurements. The ease and rapidity of measurements allow for incorporation of assessment of tactile sensitivity outcomes in diverse models of rapid-onset inflammatory and neuropathic pain as multiple measurements can be taken within a short time period. Experimental measurements for individual rodent subjects can be internally controlled against individual baseline responses and exclusion criteria easily established to standardize baseline responses within and across experimental groups. Thus, measurements using an electronic von Frey apparatus represent a useful modification of the well-established classical von Frey filament-based assays for rodent mechanical allodynia that may also be applied to other nonhuman mammalian models.

The purpose of the present study was to examine the contribution of group III and IV metabosensitive afferents at spinal and supraspinal levels in rats subjected to middle cerebral artery occlusion (MCAO) with reperfusion during the acute phase. Animals were randomized in Control (n = 23), SHAM (n = 18), MCAO-D1 (n = 10), and MCAO-D7 (n = 20) groups. Rats performed the Electrical Von Frey and the Adhesive removal tests before the surgery and at day 1 (D1), D3, and D7 after MCAO. Animals were subjected to electrophysiological recordings including the responses of group III/IV metabosensitive afferents to combinations of chemical activators and the triceps brachii somatic reflex activity at D1 or D7. The response of ventral posterolateral (VPL) thalamic nuclei was also recorded after group III/IV afferent activation. Histological measurements were performed to assess the infarct size and to confirm the location of the recording electrodes into the VPL. Behavioral results indicated that MCAO induced disorders of both mechanical sensibility and motor coordination of paretic forepaw during 7 days. Moreover, injured animals exhibited an absence of somatic reflex inhibition from the group III/IV afferents at D1, without affecting the response of both these afferents and the VPL. Finally, the regulation of the central motor drive by group III/IV afferents was modified at spinal level during the acute phase of cerebral ischemia and it might contribute to the observed behavioral disturbances.

The volar V-Y plasty is a well accepted method of management for transverse fingertip amputations. It has been suggested by some authors and assumed by some surgeons that fingertip sensation is nearly normal following the procedure. Sixteen patients with twenty fingertip injuries in our series reported an average estimate of sensitivity of 73% of normal. There was diminished sensation to testing by two-point discrimination and/or von Frey monofilament testing in all fingertips when compared to the contralateral digit. Eight patients (twelve fingertips) reported hypersensitivity, particularly cryalgia. We conclude that sensation is not normal in almost all fingertips treated by V-Y plasty for transverse amputations.

In accordance with the by-law of the American Medical Association the privilege is accorded to me, as Chairman, of opening this annual session of the Section on Pathology and Physiology. Moreover, I am geographically in a position to extend to you, its members, a welcome to the city of Boston and more especially to the laboratories of our medical schools and hospitals, and this I most cordially do. It is the privilege this year of the Section to have as guests Prof. von Frey of Wurzburg and Professor Mills of Montreal. To them, in the name of the Section, I extend a hearty welcome and a cordial invitation to take part in all of the proceedings. We feel honored by their presence and anticipate much pleasure and profit from the addresses with which they are to favor us.On this occasion it has seemed to me fitting briefly to call

In 1931 Pritchard1showed that localization of stimuli is more accurate when the skin is touched with a von Frey hair than when a warm sensation is elicited without involving the contact of a stimulator with the skin. From these experiments he concluded: Accurate localization of cutaneous stimulation is possible when the sensibility to touch is present and is in abeyance when this form of sensibility is absent. As the experiments to be described show, there is a significant difference in the accuracy of localization between experiments involving and those excluding stimulation of sensory endings in the skin by direct contact. In Pritchard's experiments, however, two types of sense organs were involved. In the first group of his experiments, in which von Frey hairs were used, the pressure end-organs which elicit touch sensation were stimulated, and in the second group the end-organs for the warmth sense. Moreover, in none

At present the modality of taste is generally considered to have four primary qualities: sweet, salt, sour, and bitter. Earlier writers have, however, accepted additional categories, one of which was the alkaline taste. The status of alkaline as a primary taste was made doubtful by the work of Oehrwall1 and Von Frey.2 Oehrwall considered the alkaline taste to be a complex excitation of one or more of the four primary tastes with touch. Von Frey suggested that the alkalies excited taste receptors and probably also stimulated olfactory receptors, due to their reactions on the surface of the tongue. More recently Moncrieff has considered the alkaline taste to be a function, not of taste but of the 'common chemical sense, since the alkalies are chemically irritating to other parts of the body as well as the tongue.3 He suggests further that more information on the alkaline taste might be obtained through a comparison of the thresholds of alkaline solutions on the tip of the tongue where there are taste buds and the mid-dorsal surface of the tongue where no taste buds exist. The inference from this suggestion is that a lack of difference in thresholds in the two areas would support his theory. The present experiment is an attempt to determine whether there is a difference between the absolute thresholds for sodium hydroxide at those areas.

St. Louis, June 1, 1903. To the Editor: —In the May 30 issue ofThe Journalappears a most excellent article by Dr. O. Beverly Campbell, under the title "The Single Cuff Method of Circular Enterorraphy. A New Method." My object in writing is to call attention to the fact that the method is not new, although I consider just as much credit due Dr. Campbell for his extensive experiments and for his logical conclusions as though he had been the first to publish the method. Die Beitrœge zur klinischen Chirurgie , Bd. XIV (1895), 1-136, contains an article by R. von Frey, entitled "Ueber Technik der Darmnaht," in which he advances as original the operative procedure which Dr. Campbell has made the basis of such good work. Von Frey operated on ten dogs, of which number nine survived; while his microscopic specimens show the condition of the line of union

When mechanical, thermal or chemical stimuli of sufficient intensity are applied to the skin, they evoke sensations of pain. At one time it was thought that excessive stimulation of any cutaneous receptor was painful, but this view was abandoned when Donaldson, von Frey and others found that there were definite touch, temperature and pain spots on the skin. According to Adrian, 1 "It is now believed that there are special receptors and conductors for pain as there are for touch and temperature, but the specific character of pain, its urgency, massiveness, etc., suggests that the receptors and conductors differ considerably from those of other types of cutaneous sensation." It has been said that there are not enough sensory fibers to supply the entire surface of the body with specific conductors for each of the varieties of cutaneous sensation. Ingbert 2 made careful counts of the myelinated fibers in the dorsal

At present there are four different theories as to the mechanism by which vibratory stimuli are perceived. Early clinical studies made with the vibrating tuning fork as the source of stimulation convinced many investigators that vibration sensibility was nothing more than the perception of repetitive mechanical stimuli delivered to the so-called deep receptors. Among these are included the pressure receptors of the skin and subcutaneous tissues, which are stimulated by mechanical forces that deform the surface of the skin, as well as those sense organs which respond to mechanical stimulation and lie in the fascia, muscles, tendons, joint capsules and periosteum of bones. Later, under the stimulus of work by von Frey,1the opinion arose that vibration was perceived by means of repetitive mechanical stimulation to the tactile receptors located in the skin and not by any other sense organs. Von Frey expressed the belief that the bone to

The frequent appearance of xerosis and keratomalacia in adults in North China, as already reported by Pillat, 1 has given me the opportunity to perform with more accuracy the examination of the generally known changes in the sensibility to touch of the cornea and the conjunctiva in the course of these diseases. On the basis of these observations, I venture to contribute to the explanation of the genesis of these diseases. METHOD OF EXAMINATION As test objects for examining sensibility, irritating hairs prepared after von Frey's 2 specifications were used. At one end of a thin wooden stick about 8 cm. in length a hair is fastened with sealing wax at right angles to the stick. The length of the hair varies according to the effect desired. The hairs used for such a test should be as straight as possible. Irritation is produced by holding the handle so