A Direct Comparison of the Skin Conductance and Skin Resistance Methods

The purpose of the present study was a direct comparison between simultaneous recordings of skin conductance and skin resistance. Sixty male students received a series of 30 white noise stimuli, while measures were taken continuously from four sites on the palmar surfaces of the fingers. Evaluations were made for response amplitudes, recovery, and for an approximate area measure. Magnitude of reactions and reliabilities were compared using ANOVA procedures. Behavioral concordances were estimated as correlations with the subjects' ratings of stimulus intensities. Conductance and resistance measures do not differ in amplitude, in area, or in strength of their reliabilities and behavioral concordances. No differences in any respect are found between sites. Skin conductance yields significantly (p < .01) shorter recovery times than skin resistance, which is discussed in terms of membrane permeability change.     

西酞普兰和文拉法新对抑郁症患者交感皮肤反应的影响

目的探讨不同药理机制的抗抑郁药西酞普兰和文拉法新对抑郁症患者交感皮肤反应（SSR）影响的差异。方法 67例抑郁症患者随机分为西酞普兰和文拉法新组,于治疗前、治疗后4周末测定SSR及汉密尔顿抑郁量表（HAM D 17）,并与35例正常对照组比较。结果①治疗前两患者组SSR潜伏期均高于对照组、波幅均低于对照组（LSD检验,P均=0.000）;治疗后,两患者组潜伏期降低（t=3.616,5.457;P=0.001,0.000）、波幅提高（t=-3.134,-6.067;P=0.004,0.000）,与对照组相比差异均有统计学意义（LSD检验,P均=0.000）;②治疗后文拉法新组SSR潜伏期变化率高于西酞普兰组（F=4.379,P=0.040）;③患者HAM D总分与SSR潜伏期呈正相关（r=0.359,P=0.003）、与波幅呈负相关（r=-0.282,P=0.021）。结论抑郁症患者SSR潜伏期异常增高、波幅异常降低,提示存在自主神经功能异常,抗抑郁药能降低SSR潜伏期、提高波幅,文拉法新的作用优于西酞普兰。     

Stimulus Site Effects on Skin Conductance Responses From the Volar Surfaces

Pulse trains were applied separately to each forefinger and to each hallux of 23 Ss to assess stimulus site effects on the relative amplitudes of skin conductance responses recorded concurrently from each palm and from each plantar surface. A binaurally presented tone was used as a non-lateralized stimulus. Analyses of the ratio of response amplitudes from contralateral recording sites indicated that for both the upper and lower extremities, responses from the volar surface of the stimulated extremity were augmented in amplitude. Responses from the volar surface of the extremity ipsilateral to the stimulus and recording sites involved the same extremity. Analyses of the ratio of response amplitudes from the palmar and plantar surfaces on the same side of the body indicated that the specific effects of stimulation did not cross the body midline. The results were interpreted as indicating a regionally differentiated sympathetic outflow to the volar sweat glands that reflects the locus of cutaneous stimulation.     

急性心肌冬眠时心脏交感神经功能的变化

目的探讨急性心肌冬眠时心脏交感神经功能的变化。方法采用大鼠离体心脏急性心肌冬眠模型,测定急性心肌冬眠时电场刺激引起心脏去甲肾上腺素(NA)的释放,并观察复灌后的酪胺反应。结果电场刺激引起的NA的溢出在心肌冬眠组、对照组和复灌组分别为3.24±1.27、76.89±27.65和80.30±23.86pmol/g.min,复灌30min时,酪胺引起NA的释放和心率明显增加,而在去甲丙咪嗪存在的情况下,酪胺的这种作用消失。结论本研究表明离体鼠心急性冬眠时,电场刺激引起的心脏NA释放明显减少,复灌后这种释放恢复至对照组水平,心脏对酪胺的NA反应证明心脏交感神经末梢功能的完整性。提示在急性心肌冬眠过程中,心脏的交感神经功能可能也经历了一个类似冬眠即神经冬眠的过程,再灌注后交感神经的功能可部分或全部恢复。     

Psychological Correlates of Nonspecific Skin Conductance Responses

Previous research has indicated that the frequency of skin conductance responses without external stimulation or motor activity is a reliable indicator of psychophysiological states and traits. Some authors have suggested that cognitions elicit nonspecific skin conductance responses. These cognitions may resemble the stimuli that evoke a specific skin conductance response. In a within subjects design (n = 31 graduate students) the onset of nonspecific skin conductance responses triggered a signal for the subject to rate cognitions on several indices. These ratings ("absent" to "fully present") were compared with samples in the absence of phasic electrodermal activity. The subjects' current concerns, negative emotion, subjective arousal, and inner speech were rated to be significantly more intense at the time of nonspecific skin conductance responses compared to electrodermal nonresponding periods. Cognitive processes seem to be concomitants of nonspecific skin conductance responses.     

The Effects of Initial Levels of Sweat Duct Filling and Skin Hydration on Electrodermal Response Amplitude

The many problems encountered in efforts to demonstrate conformance of electrodermal responses with the Law of Initial Value have been thought by Lykken and Venables to stem in part from the operation of independent central and peripheral factors. This study was an attempt at separate examination of the peripheral determinants of initial value effects using animal preparations in which the central component was interrupted. Standard electrical stimuli to sympathetic nerves were used to assess the effect of various procedures calculated to change the hydration of the corneum or to change the initial level of sweat in the ducts. Drying of the corneum can cause a marked potentiation in SRR amplitude. Increase in initial degree of duct filling does likewise. These findings are consistent with a circuit model that emphasizes the shunting effect of the corneum on the contribution of ductal resistance changes to total resistance change. Effects on SCR amplitude are more complex. The complicating effect of immediately prior activity on initial value relationships calls for considerable caution in the design and interpretation of behavioral studies that involve electrodermal measurement.     

Greater Resistance to Extinction of Electrodermal Responses Conditioned to Potentially Phobic CSs: A Noncognitive Process?

Previous results have suggested that electrodermal responses classically conditioned to potentially phobic CSs (e.g., pictures of snakes or spiders) are highly resistant to extinction and occur largely independently of cognitive expectancies. In order to test stringently for these possibilities, 144 college student subjects were administered differential classical conditioning acquisition and extinction paradigms while expectancies of the shock UCS were closely monitored. Half the subjects had potentially phobic CSs, whereas the other half had neutral CSs. Regardless of type of CS, during acquisition no evidence of electrodermal conditioning was found among subjects unaware of the CS?UCS contingency, nor was conditioning found on the pre-aware trials of subjects who became aware. During extinction, there was significantly greater resistance to extinction of electrodermal responses conditioned to potentially phobic CSs as well as a similar trend with expectancies of the UCS. However, when expectancies were equated, there was no greater resistance to extinction of electrodermal responses conditioned to potentially phobic CSs. Thus, while electrodermal responses conditioned to potentially phobic CSs did exhibit greater resistance to extinction, this conditioning was no more independent of expectancies than is conditioning with neutral CSs.     

Sympathetic Nerve Activity Underlying Electrodermal and Cardiovascular Reactions in Man

The paper summarizes results of micro-electrode recordings of sympathetic activity in human muscle and skin nerves. The nerve activity was correlated with blood pressure, plasma noradrenaline, electrodermal and/ or plethysmographic activity. Baroreflex and thermoregulatory mechanisms were studied as well as effects of arousal or emotional stimuli.     

Identification of Sites of Sympathetic Outflow During Concurrent Recordings of Sympathetic Nerve Activity and fMRI

The sympathetic division of the nervous system is critical for maintaining both resting arterial pressure and for producing changes in regional perfusion required by behavioral state changes. A primary determinant of arterial pressure is the level of vasoconstriction within skeletal muscle. It is well established that there is a tight relationship between dynamic changes in arterial pressure and muscle sympathetic nerve activity (MSNA) through the workings of the baroreflex. While the central circuitry underlying the baroreflex has been extensively investigated in anesthetized experimental animals, few studies have investigated the central circuitry responsible for the baroreflex in awake human subjects. Recently we were the first to record concurrently MSNA (using microneurography) and brain activity (using functional magnetic resonance imaging) in awake humans in a series of experiments designed to determine the central circuitry underlying the baroreflex in humans. We confirmed that the baroreflex involves activity changes within the nucleus tractus solitarius, caudal ventrolateral, and rostral ventrolateral medulla. Because conditions such as essential hypertension, obesity, and obstructive sleep apnea are all characterized by significant increases in resting MSNA, it is important to understand both brainstem and cortical sites involved in regulating resting levels of MSNA. Future investigations which define cortical sites involved in generating and modulating MSNA are important if we are to understand the underlying mechanisms of many conditions characterized by hypertension. Anat Rec, 2012. © 2012 Wiley Periodicals, Inc.     

阻断交感神经对小鼠胚胎植入和子宫局部免疫的影响

目的探究交感神经对小鼠妊娠早期胚胎发育作用的机制。方法利用组织学、免疫组织化学和酶联免疫吸附（ELISA）方法观察化学阻断剂6．羟多巴胺（6．OHDA）损毁交感神经对小鼠妊娠早期子宫局部免疫水平和早期胚胎发育的影响。结果化学损毁交感神经后，小鼠受孕率下降，胚胎植入数减少约64．4％；妊娠鼠子宫内膜固有层不发达，微血管分布少；子宫CD4^＋T细胞略有增多，而CD8^＋T细胞明显增加，特别在E3和E5，与对照组比较差异极显著（P〈0．01）；细胞因子IL-2含量升高，尤其E5升高最明显，达3．6倍，而IL-4含量仅在E5有明显升高，1L-2，1L-4比值显著升高。结论交感神经对孕小鼠子宫内膜组织学结构和子宫CD4^＋／CD8^＋T细胞与Th1／Th2细胞比值的影响可能是调控胚胎植入和早期发育的机制之一。     

The Application of the Preparatory-Response Hypothesis to Changes in Base Skin Resistance

It is deduced from physical principles that the physical intensity (and presumably the painfulness or rated intensity) of a constant-current shock should decrease with lowered skin resistance whereas that of a constant-voltage shock should increase. In terms of the preparatory-response hypothesis, therefore, base skin resistance should fall as a tonic response to background cues with constant-current shocks and rise with constant-voltage shocks. By the same token, interpolated shocks of the opposite kind in each case should be rated as more intense than those of the same kind. These predictions were confirmed experimentally.     

成人手指皮神经的免疫组织化学研究

采用 SP免疫组化的方法 ,研究 S— 10 0蛋白在人手指皮肤的感觉神经的表达情况 ,结果发现在每个真皮乳头嵴内都有 S— 10 0蛋白性标记物存在 ,标记出的结构是触觉小体。而环层小体则广泛分布在真皮网织层和皮下组织层。皮神经和其他感觉小体分布在血管和汗腺附近。本研究结果为探讨手指损伤后的感觉障碍和认识某些皮肤病的原因提供了实验资料。     

腓肠神经营养动脉皮瓣的应用解剖学研究

目的研究腓肠神经营养动脉的数量、发出位置、血管的直径,小隐静脉与腓肠神经的关系,为确定腓肠神经营养血管皮瓣提供解剖学基础。方法采用红色明胶经股动脉灌注的尸体20具(40侧),在手术显微镜下对腓肠神经营养动脉和小隐静脉进行解剖观察测量。结果腓肠神经营养动脉2～4支,各营养动脉形成血管网相互吻合,其中三支发出较为恒定。腓肠神经的上、中、下三段营养分别由上述三支动脉提供。在小腿下1/3段,小隐静脉与腓肠神经之间距离为1～5mm。腓肠神经旁组织含有与神经伴行的营养血管,其分支与皮下血管网相吻合,供应相应区域的皮瓣。结论手术时带少量神经旁筋膜组织可保证蒂部神经营养血管不被破坏。此皮瓣不损害重要血管和神经,供区比较隐蔽,可用于修复下肢远端皮肤及软组织缺损。     

Significant Differences in Sympathetic Nerve Fiber Density Among the Facial Skin Nerves: A Histologic Study Using Human Cadaveric Specimens

Sympathetic nerve fibers in the skin nerves are connected with vasomotor, thermoregulatory, sensory input modulatory, and immunologic events; however, to our knowledge, no histological information is available for skin nerves in the human face. Using specimens from 17 donated cadavers (mean age, 86 years), we measured a sectional area of tyrosine hydroxylase (TH)‐positive fibers in (1) the frontal nerve (V1), (2) the infraorbital nerve (V2), (3) the mental nerve (V3), (4) the greater auricular nerve (C2), (5) the auriculotemporal nerve (ATN), and (6) the zygomatic branch of the facial nerve (VII). The V1, V2, and V3 were obtained at their entrances to the subcutaneous tissue from the bony canal or notch. The V1, C2, ATN, and/or VII usually contained abundant TH‐positive fibers (almost 3%–8% of the nerve sectional area), whereas the V2 and V3 consistently carried few TH‐positive fibers (<1%). The difference between these two groups was quite significant (P < 0.001). Thus, from the superior cervical ganglion, the sympathetic nerve fibers reached the forehead through the frontal nerve trunk, whereas artery‐bounded fibers came to the cheek, nose, and mouth. The sympathetic palsy caused by trigeminal nerve involvement is mainly characterized by the symptoms seen in the distribution of the ophthalmic division of the trigeminal nerve, such as in Horner's syndrome. It suggests that the forehead and the other facial areas are representative parts of those different sympathetic innervations that could be useful for evaluating the sympathetic function of the face in various diseases. Anat Rec, 299:1054–1059, 2016. © 2016 Wiley Periodicals, Inc.     

腹股沟区神经皮瓣修复手外伤的解剖学基础

目的：为利用原位血管修复手外伤的腹股沟皮瓣提供感觉神经解剖资料。方法：在22侧成尸腹股沟区解剖观测髂腹下神经的走行及其分布范围。结果：髂腹下神经前皮支出现率100％，其穿出点距腹股沟区上界17．1±6.3mm，距腹股沟韧带垂直距离为19．3±3．7mm，距髂前上辫38．0±9．8mm。结论：不吻合血管行腹股沟区髂腹下神经蒂皮瓣转位对重建手的感觉功能是可行的。     

Exaggerated Sympathetic Nervous System Response to Extended Psychological Stress in Offspring of Hypertensives

The cardiovascular responses of 24 healthy young adult males with a parental history of hypertension and 24 males without a parental history of hypertension to an extended active-coping psychological stressor were compared under three drug conditions: placebo, the beta 1-blocking agent metoprolol, and the alpha 1-blocking agent prazosin. In the placebo condition, offspring of hypertensives exhibited significantly greater heart rate, blood volume pulse, and forearm blood flow responses to the task. They also exhibited a significantly greater initial decrease in forearm vascular resistance, which, in contrast to the offspring of normotensives, was no longer significantly different from baseline levels by the end of the session. No group differences in blood pressure response were observed. Metoprolol eliminated the differences in heart rate and forearm vascular resistance responses. Prazosin eliminated the difference in blood volume pulse response and elicited a sustained group difference in forearm vascular resistance. These results implicate the sympathetic nervous system in the exaggerated cardiovascular responsivity to psychological stress in individuals with a family history of essential hypertension. They also suggest that the pattern of increasing vascular resistance in response to this stressor observed in this and other studies in this laboratory reflects alpha-adrenergic activity and not neurohumorally independent autoregulation.     

Orienting and Defensive Responses to Visual Stimuli

Physiological responses were recorded while 10 females who feared spiders (Group SP) and 10 females who did not (Group NP) viewed 24 neutral and 6 spider slides. Group NP responded to the spider stimuli with heart rate (HR) deceleration and cephalic vasodilation (increase in pulse amplitude), while Group SP responded with HR acceleration and cephalic vasoconstriction. Neither group gave appreciable or systematic cardiovascular responses to the neutral stimuli. Palmar and dorsal skin conductance (SC) responses to the spider stimuli were larger than those given to the neutral slides, and tended to be larger and more resistant to habituation in Group SP than in Group NP. When considered along with post-experimental reports, the responses given by Group NP to the spider slides could be considered to be indicative of an orienting response (OR), while those given by Group SP were consistent with recent conceptions of the defensive response (DR). These response patterns, especially the latter one, were evident in both group data and in individual records.     

Active Circuits for Direct Linear Measurement of Skin Resistance and Conductance

Passive voltage-divider circuitries typically used for measuring skin resistance and conductance provide only indirect measures of these variables. Although the resulting errors of nonlinearity may not be critical for some research purposes, there is no reason why they should be tolerated, because it is possible to design simple active circuitry which avoids the errors by measuring skin resistance and conductance directly. Two such circuits are presented: a) a variable-gain voltage amplifier for direct linear measurement of skin resistance; and b) a current-to-voltage transducer for direct linear measurement of skin conductance. A combined working circuit, suitable for practical research applications, is also presented.     

Recording Skin Resistance and Beat-By-Beat Heart Rate From the Same Pair of Dry Electrodes

Changes in skin resistance and beat-by-beat heart rate, derived from the EKG, were obtained from the same pair of dry silver electrodes applied to the finger tips. The electronic criteria to be satisfied for application of this technique are discussed. The recording system was constructed using low-cost, solid-state circuitry. A typical record of changes in skin resistance and beat-by-beat heart rate is presented to demonstrate the performance characteristics of the equipment.     

Electrodermal Activity in Patients With Chronic Pain: Implications for the Specificity of Physiological Indices in Relation to Psychopathology

Abnormalities in skin conductance activity have been described for several psychiatric conditions. To date, few comparable investigations have been undertaken in patients who suffer from chronic pain syndromes in which psychogenic factors are operating. Skin conductance measurements were made using an orienting response paradigm in a sample of 100 such patients with chronic pain. The distribution of skin conductance responding/non-responding was bimodal. Significant relationships were found between orienting response categories or trials to habituation, and several other skin conductance variables, such as spontaneous responses, tonic level, response amplitude, and certain temporal characteristics of the orienting response. It was concluded that anomalies in the distribution of skin conductance responding are diagnostically non-specific and that orienting response categories are likely to be more or less arbitrary divisions on an ‘arousal’ continuum.