Browsing by Issue Date, starting with "2015-07-01"

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Delirium, Subsyndromal Delirium, and Cognitive Changes in Individuals Undergoing Elective Coronary Artery Bypass Graft Surgery
(2015-07-01)
Li, Hsiu-Ching
;
Chen, Yih-Sharng
;
Chiu, Ming-Jang
;
Fu, Mei-Chiung
;
Huang, Guan-Hua
Background: The course of incident delirium and subsyndromal delirium (SSD) after cardiac surgery is not well studied. Objective: The aim of this study was to evaluate the course of incident delirium and SSD, their risk factors, and impact on patients\' cognitive function after elective coronary artery bypass graft (CABG) surgery. Methods: Consecutive patients scheduled for an isolated CABG at a tertiary medical center in Taiwan were enrolled if they had no preoperative delirium symptoms. Delirium was assessed daily for 1 week after surgery using the Confusion Assessment Method. Subsyndromal delirium was defined as presenting with any core symptom below the diagnostic threshold for delirium. Cognitive function was assessed by the Mini-mental State Examination. Results: Of 38 participants, 7 had incident (first-time) delirium (18.4% incidence) and 13 had incident SSD (34.2% incidence). Whereas SSD usually lasted 1 day, delirium changed gradually to SSD to recovery and its symptomatology lasted longer. We identified 6 delirium risk factors: older age, more comorbidities, cardiac pulmonary bypass, blood transfusion, larger transfusion volume, and longer duration of intraoperative blood pressure less than 60 mm Hg. The frequencies of these risk factors for SSD were often intermediate between those of risk factors in groups with and without delirium. By hospital discharge, participants with delirium had the longest hospital stays and lowest cognitive scores, those with SSD had intermediate stays and scores, and those without delirium had the lowest stays and scores. Conclusion: Delirium and SSD after CABG are common. Greater number and severity of risk factors for delirium may predict increasingly poor outcomes, with the dose-response relationship between risk factors and outcomes for SSD intermediate between that for no symptoms and full delirium. Intervention trials are indicated, particularly for patients with a greater number and severity of predisposing and precipitating risk factors.
Investigation of no analogue-equalization and blue filter for 185 Mbps phosphor-LED wireless communication
(2015-07-01)
Yeh, C. H.
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Chow, C. W.
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Liu, Y. L.
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Chen, H. Y.
;
Liu, Y.
In this demonstration, we first propose an optimal analogue front end circuit without employing pre-equalization (series peaking) to increase the modulation bandwidth of phosphor-LED in visible light communication (VLC) transmission. And there is no blue filter and post-equalization in the client side. Here, only using optimal adjustment of resistance (R), inductance (L), and capacitance (C) in bias-tee to compensate the impedance matching of phosphor-LED, nearly 32 MHz modulation bandwidth can be accomplished. Therefore, utilizing orthogonal frequency division multiplexed modulation with bit-loading algorithm in VLC system, 185 Mbps data rate can be achieved under a transmission distance of 80 cm.
An investigation of unsteady flow reversal of natural convection in vertical parallel plates by the modified local one-dimensional inviscid relations method
(2015-07-01)
Fu, Wu-Shung
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Huang, Shang-Hao
;
Li, Chung-Gang
;
機械工程學系
;
Department of Mechanical Engineering
An unsteady flow reversal of natural convection in vertical parallel plates with an asymmetrically heated wall is investigated numerically. For clarifying the occurrence of flow reversal, the width of the plates is regarded as a variable, and the non-reflecting boundary condition is adopted at apertures. The methods of the Roe scheme, preconditioning and dual time stepping matching LUSGS are siinultaneously used to solve governing equations which are available for a low speed compressible flow problem. The flow reversal is observed under broad width situations and absent under narrow width situations. Distributions of the pressure differences at the apertures are revealed to indicate the occurrence of flow reversal. The present Nusselt numbers, which mean time and area-averaged ones, display relatively good agreement with those of the existing works. (C) 2015 Elsevier Ltd. All rights reserved.
具容忍變異字元線驅動抑制機制之隨機存取記憶體
(2015-07-01)
莊景德
;
林宜緯
;
陳家政
;
石維強
一種隨機存取記憶體，包含：複數個列，每一該列包含複數個記憶單元及一對應的字元線；各該記憶單元包含一個用於儲存資料的閂鎖器以及至少一閘通電晶體，耦接於該閂鎖器、該對應字元線與一對應位元線之間；複數個字元線驅動器，每一該字元線驅動器包含一電源端、一驅動端、一輸入端及一驅動電晶體；該電源端接收一工作電壓，該驅動端耦接該些列的該些字元線的其中之一，該輸入端接收一解碼訊號，該驅動電晶體包含一控制端與兩通道端，分別耦接該輸入端、該驅動端與該電源端；至少一第一追隨電晶體，各該第一追隨電晶體對應該些字元線驅動器的其中之一，包含兩通道端；其中一通道端耦接該對應字元線驅動器的該電源端及該驅動端的其中之一；該第一追隨電晶體的電子特性追隨該對應字元線驅動器中該驅動電晶體的電子特性；以及至少一第二追隨電晶體，包含一通道端，耦接該第一追隨電晶體的該兩通道端的其中之一；該第二追隨電晶體的電子特性追隨該些記憶單元中該些閘通電晶體的電子特性。
ACE2 associated with pulmonary inflammation and MMPs activities in acute lung injury by bleomycin treatment
(2015-07-01)
Hsieh, W. -Y.
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Chuang, W. -H.
;
Liu, F. -C.
;
Lin, C. -S.
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生物科技學系
Reconfigurable Custom Functional Unit Generation and Exploitation for Multiple-Issue Processors
(2015-07-01)
Wu, I-Wei
;
Shann, Jean Jyh-Jiun
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Chung, Chung-Ping
;
資訊工程學系
;
Department of Computer Science
Next-generation digital entertainment and mobile communication devices are anticipated to require greater processor performance. To meet these demands, several researchers have attached a reconfigurable hardware accelerator to the base processor core. The reconfigurable hardware accelerator, termed a reconfigurable customized functional unit (RCFU), is usually realized by multiple processing elements (PE) organized in matrix form. The structure of the RCFU is generated from hot operation patterns of specific applications. Other than the RCFU, \'multiple-issue\' is another microarchitectural technique to increase the performance. However, the impact of combining both of these approaches in the same design is not yet well understood. This problem motivates us to design RCFU generation and exploitation algorithms for a multiple-issue processor. To allow more operations to execute on the RCFU simultaneously, the proposed generation algorithm merges several data-independent operation patterns to construct the RCFU architecture. To schedule operations on both the RCFU and functional units (FU) of the base processor core simultaneously, the proposed exploitation algorithm presents a model to represent all available computing resources from both the FUs of the base processor and the PEs in the RCFU. Using this model, the RCFU exploitation problem can be considered as an instruction-scheduling problem. Our experiment achieves an average improvement in execution performance of 50% compared with previous efforts [2, 5].
60-GHz Polarization-Adjustable Antenna Arrays
(2015-07-01)
Chi, Yu-Jen
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Chen, Fu-Chiarng
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電機工程學系
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Department of Electrical and Computer Engineering
This paper proposes 2 x 2 and 4 x 4 polarization-adjustable millimeter-wave antenna arrays. The antennas were designed to function at 60 GHz and are planar and vialess. The proposed antenna designs contain two input ports; if the input phases and magnitudes of the two input ports can be controlled, enabling the proposed antenna to generate six types of polarization: right-handed circular polarization, left-handed circular polarization, and linear polarization along the phi = 0 degrees, phi = 45 degrees, phi = 90 degrees, and phi = 135 degrees axes. The achieved antenna gain of the 2 x 2 polarization diversity array was approximately 12 dBi, whereas that of the 4 x 4 array was 16 dBi. Prototypes of both the 2 x 2 and 4 x 4 arrays were fabricated and tested. The operating mechanism and design steps are described in detail in this paper.
A Miniature Magnetic-Piezoelectric Thermal Energy Harvester
(2015-07-01)
Chen, Chin-Chung
;
Chung, Tien-Kan
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Tseng, Chia-Yuan
;
Hung, Chiao-Fang
;
Yeh, Po-Chen
In this paper, we report a miniature thermal energy harvester with a novel magnetic-piezoelectric design. The harvester consists of a soft magnetic Gd cantilever beam, a piezoelectric lead zirconate titanate sheet, an NdFeB hard magnet, silicon clamps, and a silicon frame. In this design, the harvester is driven by a temperature difference between a cold side and room temperature ambient air, unlike other magnetic-piezoelectric thermal energy harvesters that are driven by a temperature difference between a cold side and a hot side or between two hot sides. Experimental results show that with a temperature difference of 20 degrees C (cold side: 6.7 degrees C, hot side: 26.7 degrees C), the harvester produces a maximum peak-to-peak voltage of 37 mV and a root mean square voltage of 1.98 mV. The estimated maximum instantaneous power density and average power density is 21.7 nW/cm(3) and 62.9 pW/cm(3), respectively. Moreover, the total volume of our harvester (length x width x height: 6 x 3.5 x 3 mm) is 217 times lower than that of previous experimental harvesters and 38 times smaller than that of previous theoretical-modeled harvesters. Therefore, our harvester is the smallest machined magnetic-piezoelectric thermal energy harvester designed to date. These features enable our harvester to be more easily implemented and integrated with micro wireless sensors and thereby increase more self-powered wireless-sensing applications.
Prioritized Optimal Channel Allocation Schemes for Multi-Channel Vehicular Networks
(2015-07-01)
Chu, Jui-Hung
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Feng, Kai-Ten
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Lin, Jia-Shi
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電機資訊學士班
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Undergraduate Honors Program of Electrical Engineering and Computer Science
The IEEE 1609.4 standard has been proposed to provide multi-channel operations in wireless access for vehicular environments (WAVE), where all channels are periodically synchronized into control and service intervals. Communication device in each vehicle will stay at the control channel for negotiation and contention during the control interval, and thereafter switch to one of the service channels for data transmission in the service interval. In this paper, based on the concept of cognitive radio (CR), the vehicles are categorized into primary providers (PPs) that intend to transmit safety-related messages and secondary providers (SPs) with non-safety information to be delivered. The prioritized optimal channel allocation (POCA) approaches are proposed to improve channel utilization of IEEE 1609.4 standard for multi-channel vehicular networks. Prioritized channel access is analyzed in the POCA schemes in order to increase the transmission opportunity of PPs. Moreover, depending on whether the CR network is distributed or centralized, the optimal channel-hopping sequence and optimal channel allocation is assigned for SPs based on dynamic programming and linear programming technique, respectively. These schemes are designed to consider optimal load balance between both channel availability and channel utilization within the throughput constraints of PPs. With the adoption of proposed POCA schemes, simulation results show that maximum throughput of SPs can be achieved with guaranteed quality-of-service requirement for PPs.
The impact of customer experience and perceived value on sustainable social relationship in blogs: An empirical study
(2015-07-01)
Chen, Shih-Chih
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Lin, Chieh-Peng
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經營管理研究所
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Institute of Business and Management
Blogs are currently powerful instrument and their proliferation has attracted substantial attention from marketing practitioners and academics. The aim of this study is to propose a model to understand and examine during the formation of sustainable social relationships and the continued usage of blogs in marketing contexts. Two exogenous constructs - customer experience and perceived value - have not only directly influenced satisfaction and intention to continue to use blogs, but also indirectly affected customers\'/citizens\' sustainable social relationship with blogs through the mediation of satisfaction and continuance intention. The analysis results herein demonstrate that sustainable social relationship is determined significantly by continuance intention and satisfaction toward blogs, while the influences of customer experience and perceived value on continuance intention are both respectively significant. However, the direct influence of customer experience on continuance intention is insignificant In addition, this study examined and empirically confirmed the mediating role of continuance intention and satisfaction on blogs between customer experience and perceived value. Finally, the findings of this research propose the detailed theoretical and managerial implications for academicians, blog operators and government agencies. (C) 2014 Elsevier Inc. All rights reserved.
Sparsity Enhanced Mismatch Model for Robust Intercell Interference Management in Heterogeneous Networks With Doubly-Selective Fading Channels
(2015-07-01)
Chang, Chieh-Yao
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Fung, Carrson C.
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電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
Transmission over doubly-selective fading (DSF) interference channel often relies on the use of robust precoder due to a lack of accurate channel state information, with performance often depending on the conservativeness of the mismatch model. Previously proposed mismatch models either have been deemed too conservative (deterministic models) or are prone to error due to inaccuracy in the probability density function (pdf) and corresponding parameters (stochastic models). A deterministic mismatch model called Sparsity Enhanced Mismatch Model-Reverse discrete prolate spheroidal sequence, or SEMMR, is proposed herein in an attempt to alleviate this problem. Different from all previously deterministic models, the proposed model exploits the inherent sparse characteristics of DSF interference channels which lead to a two-stage robust transceiver design that outperforms precoding only strategy incorporating conventional norm ball mismatch model (NBMM). The inherent sparsity in the channel is brought forth by modeling the channel using a basis expansion model (BEM) where discrete prolate spheroidal sequence (DPSS) is used as a basis. Analytical and simulation results are provided to validate the performance gains of the SEMMR transceiver over the NBMM precoder.
Innovative Fabrication of Wafer-Level InGaN-Based Thin-Film Flip-Chip Light-Emitting Diodes
(2015-07-01)
Chiang, Yen-Chih
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Lin, Bing-Cheng
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Chen, Kuo-Ju
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Lin, Chien-Chung
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Lee, Po-Tsung
In this letter, an innovative fabrication method for InGaN-based light-emitting diode (LED) was proposed, and the produced optical device was called the wafer-level InGaN-based thin-film flip-chip LEDs (wTFFC-LEDs). Packaging technologies, such as wafer-to-wafer bonding, laser lift-off, textured surface, and interconnection techniques, were applied to complete the device. Through this architecture, the absorption caused by electrodes in traditional vertical injection LEDs (V-LEDs) can be minimized, as well as the light extraction efficiency can be improved. Light-output power of wTFFC-LEDs (350 mA) was increased by 36.5% and 17.2% compared with the V-LEDs and flip-chip LEDs. Furthermore, the external quantum efficiency was also relatively enhanced by 36.3% and 15.5% higher than those of reference devices.
Angiotensin converting enzyme II deficiency accelerates the progression of COPD via irregular signaling STAT3 phosphorylation
(2015-07-01)
Hung, Y. -H.
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Hsieh, W. -Y.
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Hsieh, J. -S.
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Wu, C. -L.
;
Lin, C. -S.
Sequence Conservation, Radial Distance and Packing Density in Spherical Viral Capsids
(2015-07-01)
Chang, Chih-Min
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Huang, Yu-Wen
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Lee, Chi-Wen
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Huang, Tsun-Tsao
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Shih, Chung-Shiuan
The conservation level of a residue is a useful measure about the importance of that residue in protein structure and function. Much information about sequence conservation comes from aligning homologous sequences. Profiles showing the variation of the conservation level along the sequence are usually interpreted in evolutionary terms and dictated by site similarities of a proper set of homologous sequences. Here, we report that, of the viral icosahedral capsids, the sequence conservation profile can be determined by variations in the distances between residues and the centroid of the capsid - with a direct inverse proportionality between the conservation level and the centroid distance - as well as by the spatial variations in local packing density. Examining both the centroid and the packing density models against a dataset of 51 crystal structures of nonhomologous icosahedral capsids, we found that many global patterns and minor features derived from the viral structures are consistent with those present in the sequence conservation profiles. The quantitative link between the level of conservation and structural features like centroid-distance or packing density allows us to look at residue conservation from a structural viewpoint as well as from an evolutionary viewpoint.
電性連接結構及其製備方法
(2015-07-01)
陳智
;
劉道奇
;
黃以撒
;
劉健民
一種用以電性連接一第一基板及一第二基板之電性連接結構之製備方法，包括下列步驟：(A)提供一第一基板及一第二基板，其中該第一基板上係設有一第一銅膜，該第二基板上係設有一第一金屬膜，該第一銅膜之一第一接合面係為一含(111)面之接合面，且該第一金屬膜具有一第二接合面；以及(B)將該第一銅膜及該第一金屬膜相互接合以形成一接點，其中該第一銅膜之該第一接合面係與該第一金屬膜之該第二接合面相互對應。
Divergent Alanyl-tRNA Synthetase Genes of Vanderwaltozyma polyspora Descended from a Common Ancestor through Whole-Genome Duplication Followed by Asymmetric Evolution
(2015-07-01)
Chang, Chia-Pei
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Chang, Chih-Yao
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Lee, Yi-Hsueh
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Lin, Yeong-Shin
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Wang, Chien-Chia
Cytoplasmic and mitochondrial forms of a eukaryotic aminoacyl-tRNA synthetase (aaRS) are generally encoded by two distinct nuclear genes, one of eukaryotic origin and the other of mitochondrial origin. However, in most known yeasts, only the mitochondrial-origin alanyl-tRNA synthetase (AlaRS) gene is retained and plays a dual-functional role. Here, we present a novel scenario of AlaRS evolution in the yeast Vanderwaltozyma polyspora. Vanderwaltozyma polyspora possesses two significantly diverged AlaRS gene homologues, one encoding the cytoplasmic form and the other its mitochondrial counterpart. Clever selection of transcription and translation initiation sites enables the two isoforms to be localized and thus functional in their respective cellular compartments. However, the two isoforms can also be stably expressed and function in the reciprocal compartments by insertion or removal of a mitochondrial targeting signal. Synteny and phylogeny analyses revealed that the AlaRS homologues of Vanderwaltozyma polyspora arose from a dual-functional common ancestor through whole-genome duplication (WGD). Moreover, the mitochondrial form had higher synonymous (1.6-fold) and nonsynonymous (2.8-fold) substitution rates than did its cytoplasmic counterpart, presumably due to a lesser constraint imposed on components of the mitochondrial translational apparatus. Our study suggests that asymmetric evolution confers the divergence between the AlaRS paralogues of Vanderwaltozyma polyspora.
Hybrid Effect of Crossed Alignment and Multi-Stacking Structure on the Percolation Behavior of Silver Nanowire Networks
(2015-07-01)
Yang, Bo-Ru
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Liu, Gui-Shi
;
Han, Song-Jia
;
Cao, Wu
;
Chen, Hui-Jiuan
Owing to the superiority of being flexible, highly conductive, and extremely transparent, silver nanowire (AgNW) has been regarded as a possible candidate to replace indium-tin-oxide (ITO) for flexible transparent conductive films (TCFs), flexible electronics, and flexible display applications. To make TCFs with lower sheet resistance (R-s), but without sacrificing the optical transmittance, the deployment of AgNWs is very critical. A crossed-alignment method along with multi-stacking structure was proposed to lower the percolative threshold, which thus can decrease the R-s by a factor of more than two, in the premise of not affecting the optical transmittance.
Game-based image semantic CAPTCHA on handset devices
(2015-07-01)
Yang, Tzu-I
;
Koong, Chorng-Shiuh
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Tseng, Chien-Chao
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資訊工程學系
;
Department of Computer Science
A completely automated public turing test to tell computer and human apart (CAPTCHA) is based on the Turing test, which aims to protect Internet services from automatic script attacks and spams. However, most proposed or deployed CAPTCHAs have been breached. It is possible to enhance the security of an existing CAPTCHA by adding noises systematically adding noises, but distortions would make characters recognition difficult for humans. On the other hand, most of the traditional CPATCHAs require complicated operations using keyboards and mice which may become limitations of modern handset devices. In this study, we propose a novel GISCHA using game-based image semantics with the contributions that 1) use simple keys, mouse, gesture, and accelerometer instead of complex alphabet inputs; 2) is language independent; 3) enhances the security level without annoying users; 4) is based on more advanced human cognitive abilities; and 5) make CAPTCHAs more interesting. The experiment results show that a single GISCHA challenge was completed in 9.06 s on average with a virtual keyboard and 10.25 s on average with accelerometers build in handset devices, and the pass rate of first time use is 94.8 %, which means that it is sufficiently easy for practical use.
Resistive Switching Characteristics of WO3/ZrO2 Structure With Forming-Free, Self-Compliance, and Submicroampere Current Operation
(2015-07-01)
Tsai, Tsung-Ling
;
Lin, Yu-Hsuan
;
Tseng, Tseung-Yuen
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
The homogeneous switching of Ti/WO3/ZrO2/W resistive switching memory devices with stable resistive switching, forming-free, self-compliance, and multilevel operation characteristics are demonstrated. The area dependence of current at the low resistance and high resistance states confirms that the switching mechanisms of the devices are homogeneous conduction. The devices exhibit the stable bipolar resistive switching behavior with a low operating current (<10(-6) A) by inserting the WO3 layer with high electron affinity between the Ti top electrode and the ZrO2 layer and modulating the potential profiles at the WO3/ZrO2 interface. In addition, multilevel operation can be achieved by adjusting the magnitudes of set/reset voltages.
Relaxation and Executive Control Processes in Listeners: An Exploratory Study of Music-Induced Transient Suppression of Skin Conductance Responses
(2015-07-01)
Tsai, Chen-Gia
;
Yang, Chien-Ming
;
Chen, Chien-Chung
;
Chen, I-Ping
;
Liang, Keng-Cheng
As music unfolds over time, fluctuations in listeners\' arousal level can be assessed by physiological measures. Strong emotional feelings induced by music are usually accompanied by heightened physiological arousal as reflected by increased skin conductance responses (SCRs). The aim of this study was to demonstrate that SCRs can be suppressed by musical events; cognitive-emotional processing of music in the central nervous system may lead to decreases in sympathetic activity and transient inhibition of sweat gland innervation. We recruited nonmusicians and recorded their real-time SCRs during the presentation of musical excerpts. Among 48 musical excerpts, seven excerpts were found to transiently reduce SCR amplitude to a level below the resting control value. Music analysis revealed that anticipation of sudden accents, music-evoked feelings of tenderness, and habituation or cancellation of an alarm in listeners may be associated with significant antipeaks on the average curve of SCR amplitude. In light of the neural mechanisms underlying SCR regulation, we suggest that an antipeak of average SCR amplitude represents a physiological signature of transient relaxation or executive control. With regard to music cognition, our findings shed new light on the perception of musical-tension/relaxation contrasts, major-minor ambiguity, and musical repetitions.