BRAIN RESPONSES TO DIGITAL MUSIC: AN FNIRS STUDY

Eun-Ju Lee,Kyeong Cheon Cha,Minah Suh 글로벌지식마케팅경영학회 2018 Global Marketing Conference Vol.2018 No.07

The young generation that was born in the digital age grew up with digital technologies; they listen to music online on web sites like YouTube, which provides access to music by artists from all over the world. We conducted a functional near-infrared spectroscopy (fNIRS) experiment with fifty-six young adults. The human brain generates electrical waves as long as it lives. Since the dynamic nature of brain rhythm is at work in all kinds of human brain function, neuroscientists have used brain rhythm to understand brain function. Since the work of Gerstein and Mandelbrot (1964), many attempts have been made to use random-walk analyses to account for brain responses like the spiking of neurons, cell migration, and motor variability. Like any other biological system, the brain pursues functional efficiency at all levels of operation—in the brain’s case, from the neuronal cell level to the neural network level. Before one can determine the presence of a periodic rhythm versus a random state in brain activation, one must determine whether external stimuli can shape the brain’s modulation pattern. Brain-wave patterns are affected by whether the neural circuit that governs a particular set of brain functions reaches a significant level of activation. The bottom-up processing of external stimuli can be affected by top-down processing; in other words, the execution of higher-order cognitive attention can affect the degree of randomness in the bottom-up processing of external sensory inputs like that of music. Unlike EEG signals, the rhythms of hemodynamic signals are not commonly calculated, possibly because hemodynamic signals are sluggish. The random-walk test on neural time series has been applied only recently to magnetoencephalography (MEG) data (Kipi?ski, K?nig, Sielu?ycki, & Kordecki, 2011), and it has rarely been applied to hemodynamic signals measured with magnetic resonance imaging (MRI) or near-infrared spectroscopy (NIRS). However, since hemodynamic responses are the result of neurovascular coupling—a dynamic event among the brain’s neurons, glias, and vasculatures—it is possible to calculate the degree of randomness of hemodynamic signals as surrogates for neuronal activity. While brain activities are inherently random and noisy in their natural state, when the brain rhythm is modified by music that provides appropriate levels of sensory stimulation, the brain’s signals will begin to reflect the music’s rhythms. This reflection is called “attunement.” The effect of sensori-neural stimulation on hemodynamic responses measured by fNIRS has been reported in neuroscience research that found that auditory stimulation and music elevated the concentrations of oxygenated hemoglobin (HbO2) and total hemoglobin (HbT) in blood flow to certain regions of the brain (Hoshi & Tamura, 1993; Kotilahti et al., 2010; Sakatani, Chen, Lichty, Zuo, & Wang, 1999). However, studies have shown decreases (increases) in children’s (adults’) prefrontal cerebral volume after they play computer games. For example, one study suggested that the level of attention may modulate the directional changes in HbO2 and HbT concentrations (Nagamitsu, Nagano, Yamashita, Takashima, & Matsuishi, 2006). The brains of children who find that a game lacks adequate levels of perceptual stimulation do not require an additional supply of oxygen, but adults who find playing the same game a cognitive challenge require more effort to perform the same task, so they require elevated levels of oxygen in their brains (Ferreri et al., 2014). According to musical theorists, when the brain is entrained, the attention follows the music (London, 2012). When members of the digital generation listen to music, the perceptual stimulation level is likely to related to the degree of randomness in brain responses as well as the quality of the sensory experience. Drawing on the literature review, we predict that TBF is higher for a stimulus that is above OSL than the TBF for a counterpart stimulus that is below OSL. We also predict that the hemodynamic rhythm of related brain regions to music that is above OSL adopts a regular predictable pattern. Hence, we propose the following research hypotheses: H1: Digital music that provides acoustic stimulation near the OSL creates brain responses in the form of higher TBF and lower randomness in HbO2 concentrations than does digital music that provides acoustic stimulation that is below the OSL. Functional Near-infrared Spectroscopy The transparency of biological tissue to light in the near-infrared wavelengths makes NIRS possible. NIRS is non-invasive and portable, and it has a cost advantage. The incident near-infrared light from a transmitting optode (source) is scattered through the tissues, and the reflected light is detected by a receiving optode (detector). The amount of the source light that a tissue absorbs depends on the light’s wave length, and the oxygenation status determines the brain’s absorption of the light. The loss of the intensity that is due to the absorption of the photons can be measured in units of optical density (Zaramella et al., 2001). The changes in [oxy-Hb] and [deoxy-Hb] can be calculated according to the modified Beer-Lambert law (Kocsis, Herman, & Eke, 2006) using two wave lengths of near-infrared light—in our case, 780 and 850nm. We used a 12-channel wireless fNIRS system (Biomedical Optics Lab, Korea University) with sampling rates of 8 ~10 Hz to measure the participants’ hemodynamic response while they watched the videos. The system consists of three light sources and five detectors (a 3×7 grid). The fNIRS probe was attached to each subject’s forehead. The detectors of the lowest line were set along the Fp1 and Fp2 electrode line according to the international 10/20 system. Measurements from channels 1, 2, 11, and 12, which contained noise from movements of the subjects’ heads, hair, and sweat, were excluded from further analysis. Neuroscience research has recorded acoustic stimulation in various regions of the brain, including the temporal brains of newborn babies (Hoshi & Tamura, 1993) and the frontal brains of adults (Sakatani et al., 1999). Since infrared light cannot penetrate hair, brain regions that are not covered by hair, such as the prefrontal cortex, are well-suited to an fNIRS study. When a member of the digital generation listens to music online, the motivation is usually enjoyment, so brain activity changes that are due to popular music should occur in brain areas that are associated with reward-related processing—that is, the medial pre-frontal cortex (mPFC) (Haber & Knutson, 2010). As the mental function of pleasurable experience that is modulated in the medial frontal cortex increases, TBF to this region increases. In particular, the processing of sounds is dominantly modulated by the brain’s right hemisphere (Kaiser, Lutzenberger, Preissl, Ackermann, & Birbaumer, 2000). We analyzed TBF to the right brain area of the mPFC at channel 5 using fNIRS. The research hypothesis predicts that songs that provide strong sensory stimulation above the OSL increase the TBFs of those in the digital generation more than do songs that present a sensory stimulation level that is much under the OSL. TBF can be directly obtained as a product of HbT (Wyatt et al., 1990). After the music began in the experiment, the subjects’ concentrations of HbT increased until HbT reached its peak at around five to eight seconds; then it decreased for the next thirty seconds. There was a divide of hemodynamic responses between the two songs that had more than a million hits per day (A and B) and the remaining three (C, D, and E). We conducted repeated measures of ANOVA on TBF, measured at forty seconds, for the five songs, since TBF at the end of each set of song segments can represent the digital generation’s level of sustained attention. The multivariate test for the model was significant, and the main effect of songs on TBF was significant (Wilk’s Lambda 0.75, F(4,51)=4.249, p=0.005, ???? ). After the forty seconds of each song were over, the TBF levels remained at the highest level for song A, followed in order by Songs B, C, D, and E. Pairwise comparisons after the Bonferroni correction showed that there was a significant divide in the length of time that the TBF levels remained at the highest level between songs A/B and songs C/D/E (p<0.05). Other differences were not significant, possibly because the neural data contained large individual difference variances (between-subject F test: F(1,54) =38.501, .p<0.001,???? ). The results support hypothesis 1. Next, we examined the relationships between TBF and daily hits, and BORP and daily hits. The Pearson correlation coefficient between TBF and daily hits was 0.88 (p<0.05), and the correlation coefficient between BORP and daily hits was -0.96 (p<0.05). Pairwise comparisons after the Bonferroni correction showed that, there was a significant divide in the length of time that the TBF levels remained at the highest level between songs A/B and songs D/E (p<0.05). Other differences were not significant, possibly because neural data contains a large portion of individual variance (between-subject F test: F(1,54) =372.675, p<0.001, ???? ). These results are consistent with our hypothesis 1b that pop music that presents stimulation above OSL can reduce the randomness in hemodynamic signals. The changes in the participants’ hemoglobin concentrations while they listened to popular songs show a mean-reverting tendency with low BORP—a “rhythm” such that a system recovers order and balance in due time. The brain’s response to less popular songs were random-walk processes, which represents a neural drain, a process in which brain fails to recover from oxygen depletion because of boredom. In conclusion, we found that total blood flow to the right medial prefrontal cortex increased less when the young adults were exposed to music that presented acoustic stimulation near the optimal sensory load (OSL) than it did when they were exposed to songs with a level of stimulation much below the OSL. The degrees of hemodynamic randomness decreased significantly while the participants listened to online music that provided near-OSL stimulation. Online popularity, recorded as the number of daily hits, was significantly positively correlated with the total blood flow and negatively correlated with hemodynamic randomness. These findings suggest that a new digital media strategy may be required that provides a sufficient level of sensory stimulation as an essential part of marketing to the digital consumer generation.

Inverted near-infrared organic photodetector with oriented lead (II) phthalocyanine molecules via substrate heating

Choi, Min-Soo,Lee, Siwoo,Kim, Hyo Jung,Kim, Jang-Joo Elsevier 2018 ORGANIC ELECTRONICS Vol.61 No.-

<P><B>Abstract</B></P> <P>We developed a lead (II) phthalocyanine (PbPc)-based inverted organic photodetector (OPD) detecting near-infrared (NIR) wavelength near 940 nm. Such inverted OPDs can be combined with n-channel silicon-based integrated circuits. Operation near 940 nm is crucial in terms of daylight applications because the intensity of sunlight is low near that wavelength. A spectral response to 1000 nm was achieved by depositing PbPc on a heated C<SUB>60</SUB> layer to form a triclinic rather than a monoclinic phase. This exhibited a much higher responsivity (35.8 mA/W at 960 nm) compared to a device fabricated without substrate heating (8.4 mA/W). The external quantum efficiency also increased from 0.9 to 4.4%.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Controlling an initial growth mode to form triclinic phase near the C<SUB>60</SUB>/PbPc interface via substrate heating. </LI> <LI> Triclinic phase near the interface results in external quantum efficiency and responsivity in near-infrared region. </LI> <LI> Higher responsivity (35.8 mA/W at 960 nm) compared to a device fabricated without substrate heating (8.4 mA/W). </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Near-infrared face recognition by fusion of E-GV-LBP and FKNN

( Weisheng Li ),( Lidou Wang ) 한국인터넷정보학회 2015 KSII Transactions on Internet and Information Syst Vol.9 No.1

To solve the problem of face recognition with complex changes and further improve the efficiency, a new near-infrared face recognition algorithm which fuses E-GV-LBP and FKNN algorithm is proposed. Firstly, it transforms near infrared face image by Gabor wavelet. Then, it extracts LBP coding feature that contains space, scale and direction information. Finally, this paper introduces an improved FKNN algorithm which is based on spatial domain. The proposed approach has brought face recognition more quickly and accurately. The experiment results show that the new algorithm has improved the recognition accuracy and computing time under the near-infrared light and other complex changes. In addition, this method can be used for face recognition under visible light as well.

저조도 안개 환경에서 열화상 카메라를 이용한 이미지 가시성 향상에 관한 연구

이창섭 ( Chang Seop Lee ),하동환 ( Dong Hwan Har ) 현대사진영상학회 2017 현대사진영상학회논문집 Vol.20 No.3

This research aimed to improve visibility using Long Wave Infrared by recognizing the limitations of improving the visible, near-infrared images’s visibility through the fog improvement algorithm. First of all, we prepared an imaging system that could acquire visible, near-infrared, long wave infrared images for experiments. also, we demonstrated how improvements in the visible and infrared images through De-hazed algorithm. A numerical analysis was conducted using the CNR(Contrast to Noise Ratio) to analyze the image of before & after. and we demonstrated how differences with long wave infrared under the low light level and aerosol environments. this research is meaningful in terms of providing to obtain and analyze accurate information in a specific environment that does not improve visible and near-infrared images’s visibility.

고굴절 다공성 하이브리드 실리카 입자의 다중 광산란 효과를 이용한 근적외선 차단 소재

박찬범,김상희,이금정,이지현,이준배,권혁회,이준협 한국고분자학회 2023 폴리머 Vol.47 No.1

Since near-infrared rays have long wavelengths, they typically show low light scattering effect and easily penetrate the air. Consequently, when directly irradiated on the skin, they penetrate deep into the skin to raise the skin temperature, accelerate aging, and create wrinkles. Therefore, a new material technology is essential for near-infrared protection. In this study, we intend to propose a new core-shell type hybrid material that exhibits high near-infrared blocking properties through multiple light scattering effect by physically coating high-refractive index TiO2 nanoparticles on the surface of porous silica microparticle in an island form. Highly refractive hybrid silica particles were prepared by introducing TiO2 nanoparticles into the porous silica surface through a simple solution dispersion method. Near-infrared reflectance measurements confirmed that the actual sunscreen formulation as well as the prepared pristine hybrid silica particles exhibited excellent near-infrared blocking performance.

1P-101 Near-infrared responsive monoolein cubic phase containing gold nanoparticles and polyethyleneimine/cinnamic acid conjugate

박단비,김진철 한국공업화학회 2017 한국공업화학회 연구논문 초록집 Vol.2017 No.1

The positively charged polyethyleneimine (PEI) and the negatively charged cinnamic acid (CA) form conjugate by electrostatic interactions. Conjugates can form a self-assembly in aqueous phase because they exhibit amphipathic properties. Gold nanoparticles (GNP) are known to generate heat due to near-infrared surface plasmon resonance. As the temperature increases, the PEI/CA self-assembly loses its amphipathic property and disintegrates as the solubility of CA (the hydrophobic molecule) increases. The near-infrared responsive drug delivery vehicle was prepared by loading GNP and PEI/CA selfassembly on cubic phase. The cubic phase consists of a lipid bilayer and water channel, and this structure was observed through a transmission electron microscope. The release profile of fluorescent dye loaded on cubic phase was observed under near-infrared irradiation.

근적외선 투과 성능 개선을 통한 차량용 나이트 비전 카메라의 화질 향상에 대한 연구

전대홍(Daehong Jeon),김기현(Kihyeon Kim),강호준(Hojoon Kang),변동규(Dongkyu Byeon),손수락(Surak Shon) 한국자동차공학회 2009 한국자동차공학회 부문종합 학술대회 Vol.2009 No.4

One of Advanced Safety Vehicle (ASV) technique, Night Vision Uses near-infreared of far-infrared to assure the sight. This paper only discuss about the Night Vision Camera, which uses the near-infrared. Night Vision, which uses the near-infrared , doesn't give dazzling to the driver of on-coming traffic and can monitor the road status in night time. it's possible to reduce the blooming, which is the one of reason that affects the image quality of the near-infrared camera by the use of WDR(Wide Dynamic Range)Camera. This paper suggests the improvement of an automotive night vision camera through the near-infrared transmission enhancement, and proves the improvement of image quality by the examination.

Clinical Application of Near-Infrared Spectroscopy in Neonates

전가원 대한신생아학회 2019 Neonatal medicine Vol.26 No.3

The incidence of cerebral palsy has not decreased despite advances in neonatal care. Preterm infants are at a high risk of cerebral palsy. Moreover, preterm infants might experience permanent neurological sequelae due to injury in the preterm brain. Although the etiology of preterm brain injury is not fully understood, preterm brain injury is strongly associated with abnormal cerebral perfusion and oxygenation. Monitoring systemic blood pressure or arterial oxygen saturation using pulse oximetry is not enough to guarantee proper cerebral perfusion or oxygenation. Early detection of improper cerebral perfusion can prevent irreversible cerebral damage. To decrease brain injury through the early detection of under-perfusion and deoxygenation, other diagnostic modalities are needed. Near-infrared spectroscopy can continuously and noninvasively monitor regional oxygen saturation (rSO2), which reflects the perfusion and oxygenation status of tissues at bedside. Near-infrared spectroscopy represents a balance between tissue oxygen supply and demand. Cerebral rSO2 monitoring has been used most frequently in neonatal cardiac surgery to monitor cerebral oxygenation and prevent hypoxic damage or shock. Recently, cerebral, renal, or splanchnic rSO2 in neonates is frequently monitored. The progression of a disease, brain injury, and death can be prevented by detecting changes in rSO2 values using near-infrared spectroscopy. In this article, the basic principles, usefulness, and applications of near-infrared spectroscopy in neonates are discussed.

Multi-Layer Inkjet Printing of Ag Nanoparticle Inks and Its Sintering with a Near-Infrared System

성기학,박장훈,강현규 한국정밀공학회 2018 International Journal of Precision Engineering and Vol.19 No.2

This paper proposes process guidelines for inkjet printing with a multi-layer printing and near-infrared sintering. Ag nanoparticles and polymer substrate were used in this experiment. The lowest sheet resistance of 1.38 Ω/□ was achieved with four layers printing and 33-J/cm2 energy density. Meanwhile, the highest percentage of Ag bulk conductivity obtained was 8.97% with a 121-nm thickness and 33-J/cm2 energy density. This study examined the correlation among the operating conditions, thickness, and conductivity of the printed patterns fabricated by the drop-on-demand inkjet printing and near-infrared sintering system. A statistical methodology was conducted to identify the most dominant factor. The number of printing and energy density of near-infrared lamp were found to be significant factors affecting the thickness and conductivity of the printed layers, respectively. The findings of this study confirm the potential of inkjet printing and near-infrared sintering for fabricating thick layers for three-dimensional structure and flexible printed circuits.

근적외선 업컨버전 나노입자를 이용한 광촉매 성능 향상

박용일 ( Yong Il Park ) 한국공업화학회 2021 공업화학 Vol.32 No.2

일반적인 반도체 기반의 광촉매는 물질 고유의 밴드갭 때문에 자외선이나 가시광선에 의해서만 활성화될 수 있고, 태양광 에너지의 약 50%를 차지하는 근적외선 영역의 에너지는 활용할 수 없다. 따라서 기존의 반도체 광촉매의 성능을 향상시키기 위해서는 자외선에서 근적외선에 이르는 넓은 영역에서 더 많은 태양광 에너지를 활용할 수 있어야 한다. 태양광의 근적외선 영역을 활용하기 위해 기존 반도체 광촉매를 업컨버전 나노입자와 결합하는 연구들이 수행되고 있다. 업컨버전 나노입자는 근적외선 광자를 여러 개 흡수하여 자외선이나 가시광선으로 변환하여 광촉매를 활성화할 수 있다. 그리고 반도체 광촉매와 업컨버전 나노입자에 플라즈모닉 금속 나노입자를 함께 결합시키면 태양광에 의한 광촉매 활성을 더욱 향상시킬 수 있다. 본 총설은 업컨버전 나노입자를 이용하여 근적외선 영역의 태양광에너지가 광촉매의 성능 향상에 기여할 수 있도록 하는 최근의 연구결과를 바탕으로 서술하였다. Semiconductor-based photocatalysts can only be activated with ultraviolet or visible light due to their intrinsic bandgap, and they cannot use the energy in the near-infrared region, which accounts for about 50% of solar energy. Therefore, in order to improve the performance of the semiconductor photocatalyst, it is necessary to utilize more solar energy in a broad band ranging from ultraviolet to near-infrared. Combining upconversion nanoparticles with semiconductor photocatalysts for near-infrared absorption have thus been reported. Upconversion nanoparticles can sequentially absorb multiple near-infrared photons and convert them into ultraviolet or visible to activate photocatalysts. In addition, by coupling the semiconductor photocatalyst and the upconversion nanoparticles with the plasmonic metal nanoparticles, the photocatalytic activity can be further improved. This review summarizes the recent studies on improving the photocatalytic performance with near-infrared absorption by using upconversion nanoparticles.