메뉴 건너뛰기




Volumn 121, Issue 1, 1998, Pages 143-157

Human cerebral activity evoked by motion reversal and motion onset. A PET study

Author keywords

Contrast modulation; Functional MRI; Human VEPs; Motion; PET

Indexed keywords

ADULT; ARTICLE; CLAUSTRUM; CONTRAST; CONTROLLED STUDY; ELECTROENCEPHALOGRAM; EVOKED VISUAL RESPONSE; HUMAN; HUMAN EXPERIMENT; INSULA; MALE; MOTION; NORMAL HUMAN; OCCIPITAL LOBE; PARIETAL LOBE; POSITRON EMISSION TOMOGRAPHY; PRIORITY JOURNAL; TEMPORAL LOBE;

EID: 0031963337     PISSN: 00068950     EISSN: None     Source Type: Journal    
DOI: 10.1093/brain/121.1.143     Document Type: Article
Times cited : (36)

References (68)
  • 1
    • 0021682665 scopus 로고
    • Direction and orientation selectivity of neurons in visual area MT of the macaque
    • Albright TD. Direction and orientation selectivity of neurons in visual area MT of the macaque. J Neurophysiol 1984; 52: 1106-30.
    • (1984) J Neurophysiol , vol.52 , pp. 1106-1130
    • Albright, T.D.1
  • 2
    • 0021332025 scopus 로고
    • Columnar organization of directionally selective cells in visual area MT of the macaque
    • Albright TD, Desimone R, Gross CG. Columnar organization of directionally selective cells in visual area MT of the macaque. J Neurophysiol 1984; 51: 16-31.
    • (1984) J Neurophysiol , vol.51 , pp. 16-31
    • Albright, T.D.1    Desimone, R.2    Gross, C.G.3
  • 6
    • 0015526410 scopus 로고
    • Visual evoked potentials to sudden reversal of the motion of a pattern
    • Clarke PGH. Visual evoked potentials to sudden reversal of the motion of a pattern. Brain Res 1972; 36: 453-8.
    • (1972) Brain Res , vol.36 , pp. 453-458
    • Clarke, P.G.H.1
  • 7
    • 0016261625 scopus 로고
    • Are visual evoked potentials to motion-reversal produced by direction-sensitive brain mechanisms?
    • Clarke PGH. Are visual evoked potentials to motion-reversal produced by direction-sensitive brain mechanisms? Vision Res 1974; 14: 1281-4.
    • (1974) Vision Res , vol.14 , pp. 1281-1284
    • Clarke, P.G.H.1
  • 8
    • 0024995866 scopus 로고
    • Occipital cortex in man: Organization of callosal connections, related myelo- And cytoarchitecture, and putative boundaries of functional visual areas
    • Clarke S, Miklossy J. Occipital cortex in man: organization of callosal connections, related myelo-and cytoarchitecture, and putative boundaries of functional visual areas. J Comp Neurol 1990; 298: 188-214.
    • (1990) J Comp Neurol , vol.298 , pp. 188-214
    • Clarke, S.1    Miklossy, J.2
  • 9
    • 0023859091 scopus 로고
    • Topographical organization of cortical afferents to extrastriate visual area PO in the macaque: A dual tracer study
    • Colby CL, Gattass R, Olson CR, Gross CG. Topographical organization of cortical afferents to extrastriate visual area PO in the macaque: a dual tracer study. J Comp Neurol 1988; 269: 392-413.
    • (1988) J Comp Neurol , vol.269 , pp. 392-413
    • Colby, C.L.1    Gattass, R.2    Olson, C.R.3    Gross, C.G.4
  • 14
    • 0029598787 scopus 로고
    • The parallel visual motion inputs into areas V1 and V5 of human cerebral cortex
    • ffytche DH, Guy CN, Zeki S. The parallel visual motion inputs into areas V1 and V5 of human cerebral cortex. Brain 1995; 118: 1375-94.
    • (1995) Brain , vol.118 , pp. 1375-1394
    • Ffytche, D.H.1    Guy, C.N.2    Zeki, S.3
  • 16
    • 0002990752 scopus 로고    scopus 로고
    • Imaging cognitive anatomy
    • Fristen KJ. Imaging cognitive anatomy. Trends Cogn Sci 1997; 1: 21-7.
    • (1997) Trends Cogn Sci , vol.1 , pp. 21-27
    • Fristen, K.J.1
  • 21
    • 0025855125 scopus 로고
    • Functional properties of neurons in the anterior bank of the parieto-occipital sulcus of the macaque monkey
    • Galletti C, Battaglini PP, Fattori P. Functional properties of neurons in the anterior bank of the parieto-occipital sulcus of the macaque monkey. Eur J Neurosci 1991; 3: 452-61.
    • (1991) Eur J Neurosci , vol.3 , pp. 452-461
    • Galletti, C.1    Battaglini, P.P.2    Fattori, P.3
  • 22
    • 0030069880 scopus 로고    scopus 로고
    • Functional demarcation of a border between areas V6 and V6a in the superior parietal gyrus of the macaque monkey
    • Galletti C, Fattori P, Battaglini PP, Shipp S, Zeki S. Functional demarcation of a border between areas V6 and V6A in the superior parietal gyrus of the macaque monkey. Eur J Neurosci 1996; 8: 30-52.
    • (1996) Eur J Neurosci , vol.8 , pp. 30-52
    • Galletti, C.1    Fattori, P.2    Battaglini, P.P.3    Shipp, S.4    Zeki, S.5
  • 23
    • 0025054414 scopus 로고
    • Localization and responses of neurones in the parieto-insular vestibular cortex of awake monkeys (Macaca fascicularis)
    • Lond
    • Grüsser OJ, Pause M, Schreiter U. Localization and responses of neurones in the parieto-insular vestibular cortex of awake monkeys (Macaca fascicularis). J Physiol (Lond) 1990; 430: 537-57.
    • (1990) J Physiol , vol.430 , pp. 537-557
    • Grüsser, O.J.1    Pause, M.2    Schreiter, U.3
  • 24
    • 85039724885 scopus 로고    scopus 로고
    • Cross-modal transfer of information between the tactile and the visual systems in the human brain-a PET study [abstract]
    • Hadjikhani N, Roland PE. Cross-modal transfer of information between the tactile and the visual systems in the human brain-a PET study [abstract]. Neuroimage 1996; 3 (3 Pt 2): S363.
    • (1996) Neuroimage , vol.3 , Issue.2-3 PART
    • Hadjikhani, N.1    Roland, P.E.2
  • 25
    • 0031060037 scopus 로고    scopus 로고
    • Human cortical oscillations: A neuromagnetic view through the skull
    • Hari R, Salmelin R. Human cortical oscillations: a neuromagnetic view through the skull. [Review]. Trends Neurosci 1997; 20: 44-9.
    • (1997) Trends Neurosci , vol.20 , pp. 44-49
    • Hari, R.1    Salmelin, R.2
  • 27
    • 0026455807 scopus 로고
    • Visual evoked potentials specific for motion onset
    • Kuba M, Kubova Z. Visual evoked potentials specific for motion onset. Doc Ophthalmol 1992; 80: 83-9.
    • (1992) Doc Ophthalmol , vol.80 , pp. 83-89
    • Kuba, M.1    Kubova, Z.2
  • 28
    • 0028800806 scopus 로고
    • Contrast dependence of motion-onset and pattern-reversal evoked potentials
    • Kubova Z, Kuba M, Spekreijse H, Blakemore C. Contrast dependence of motion-onset and pattern-reversal evoked potentials. Vision Res 1995; 35: 197-205.
    • (1995) Vision Res , vol.35 , pp. 197-205
    • Kubova, Z.1    Kuba, M.2    Spekreijse, H.3    Blakemore, C.4
  • 29
    • 0027413120 scopus 로고
    • Speed and direction selectivity of macaque middle temporal neurons
    • Lagae L, Raiguel S, Orban GA. Speed and direction selectivity of macaque middle temporal neurons. J Neurophysiol 1993; 69: 19-39.
    • (1993) J Neurophysiol , vol.69 , pp. 19-39
    • Lagae, L.1    Raiguel, S.2    Orban, G.A.3
  • 31
    • 0029997609 scopus 로고    scopus 로고
    • Interactions between electrical activity and cortical microcirculation revealed by imaging spectroscopy: Implications for functional brain mapping
    • Malonek D, Grinvald A. Interactions between electrical activity and cortical microcirculation revealed by imaging spectroscopy: implications for functional brain mapping. Science 1996; 272: 551-4.
    • (1996) Science , vol.272 , pp. 551-554
    • Malonek, D.1    Grinvald, A.2
  • 32
    • 0029078687 scopus 로고
    • Processing of kinetically defined boundaries in the cortical motion area MT of the macaque monkey
    • Marcar VL, Xiao DK, Raiguel SE, Maes H, Orban GA. Processing of kinetically defined boundaries in the cortical motion area MT of the macaque monkey. J Neurophysiol 1995; 74: 1258-70.
    • (1995) J Neurophysiol , vol.74 , pp. 1258-1270
    • Marcar, V.L.1    Xiao, D.K.2    Raiguel, S.E.3    Maes, H.4    Orban, G.A.5
  • 33
    • 0020541361 scopus 로고
    • Functional properties of neurons in middle temporal visual area of the macaque monkey. I. Selectivity for stimulus direction, speed, and orientation
    • Maunsell JHR, Van Essen DC. Functional properties of neurons in middle temporal visual area of the macaque monkey. I. Selectivity for stimulus direction, speed, and orientation. J Neurophysiol 1983; 49: 1127-47.
    • (1983) J Neurophysiol , vol.49 , pp. 1127-1147
    • Maunsell, J.H.R.1    Van Essen, D.C.2
  • 34
    • 0031004314 scopus 로고    scopus 로고
    • Infrequent events transiently activate human prefrontal and parietal cortex as measured by functional MRI
    • McCarthy G, Luby M, Gore J, Goldman-Rakic P. Infrequent events transiently activate human prefrontal and parietal cortex as measured by functional MRI. J Neurophysiol 1997; 77: 1630-4.
    • (1997) J Neurophysiol , vol.77 , pp. 1630-1634
    • McCarthy, G.1    Luby, M.2    Gore, J.3    Goldman-Rakic, P.4
  • 35
    • 0028798105 scopus 로고
    • Brain activation associated with visual motion studied by functional magnetic resonance imaging in humans
    • McCarthy G, Spicer M, Adrignolo A, Luby M, Gore J, Allison T. Brain activation associated with visual motion studied by functional magnetic resonance imaging in humans. Hum Brain Mapp 1995; 2: 234-43.
    • (1995) Hum Brain Mapp , vol.2 , pp. 234-243
    • McCarthy, G.1    Spicer, M.2    Adrignolo, A.3    Luby, M.4    Gore, J.5    Allison, T.6
  • 36
    • 0022548773 scopus 로고
    • Motion selectivity in macaque visual cortex. I. Mechanisms of direction and speed selectivity in extrastriate area MT
    • Mikami A, Newsome WT, Wurtz RH. Motion selectivity in macaque visual cortex. I. Mechanisms of direction and speed selectivity in extrastriate area MT. J Neurophysiol 1986; 55: 1308-27.
    • (1986) J Neurophysiol , vol.55 , pp. 1308-1327
    • Mikami, A.1    Newsome, W.T.2    Wurtz, R.H.3
  • 37
    • 0025034429 scopus 로고
    • Three-dimensional magnetization-prepared rapid-gradient-echo imaging (3D MP RAGE)
    • Mugler JP, Brookeman JR. Three-dimensional magnetization-prepared rapid-gradient-echo imaging (3D MP RAGE). Magn Reson Med 1990; 15: 152-7.
    • (1990) Magn Reson Med , vol.15 , pp. 152-157
    • Mugler, J.P.1    Brookeman, J.R.2
  • 38
    • 0026952545 scopus 로고
    • Posterior cingulate cortex: Sensory and oculomotor properties of single neurons in behaving cat
    • Olson CR, Musil SY. Posterior cingulate cortex: sensory and oculomotor properties of single neurons in behaving cat. Cereb Cortex 1992; 2: 458-502.
    • (1992) Cereb Cortex , vol.2 , pp. 458-502
    • Olson, C.R.1    Musil, S.Y.2
  • 39
    • 0029910041 scopus 로고    scopus 로고
    • Single neurons in posterior cingulate cortex of behaving macaque: Eye movement signals
    • Olson CR, Musil SY, Goldberg ME. Single neurons in posterior cingulate cortex of behaving macaque: eye movement signals. J Neurophysiol 1996; 76: 3285-300.
    • (1996) J Neurophysiol , vol.76 , pp. 3285-3300
    • Olson, C.R.1    Musil, S.Y.2    Goldberg, M.E.3
  • 40
    • 0002987298 scopus 로고
    • Quantitative electrophysiology of visual cortical neurones
    • Leventhal AG, editor. Basingstoke (UK): Macmillan Press
    • Orban GA. Quantitative electrophysiology of visual cortical neurones. [Review]. In: Leventhal AG, editor. The neural basis of visual function. Vision and visual dysfunction. Basingstoke (UK): Macmillan Press, 1991; 4: 173-222.
    • (1991) The Neural Basis of Visual Function. Vision and Visual Dysfunction , vol.4 , pp. 173-222
    • Orban, G.A.1
  • 41
    • 0000404915 scopus 로고    scopus 로고
    • Visual processing in macaque area MT/V5 and its satellites (MSTd and MSTv)
    • Kaas JH, Rockland KS, Peters A, editors. New York: Plenum Press, In press
    • Orban GA. Visual processing in macaque area MT/V5 and its satellites (MSTd and MSTv). [Review]. In: Kaas JH, Rockland KS, Peters A, editors. Cereb Cortex. New York: Plenum Press, 1997. In press.
    • (1997) Cereb Cortex
    • Orban, G.A.1
  • 42
    • 0022482933 scopus 로고
    • Velocity sensitivity and direction selectivity of neurons in areas V1 and V2 of the monkey: Influence of eccentricity
    • Orban GA, Kennedy H, Bullier J. Velocity sensitivity and direction selectivity of neurons in areas V1 and V2 of the monkey: influence of eccentricity. J Neurophysiol 1986; 56: 462-80.
    • (1986) J Neurophysiol , vol.56 , pp. 462-480
    • Orban, G.A.1    Kennedy, H.2    Bullier, J.3
  • 43
    • 0028535376 scopus 로고
    • Cortical potentials reflecting motion processing in humans
    • Patzwahl DR, Zanker JM, Altenmüller EO. Cortical potentials reflecting motion processing in humans. Vis Neurosci 1994; 11: 1135-47.
    • (1994) Vis Neurosci , vol.11 , pp. 1135-1147
    • Patzwahl, D.R.1    Zanker, J.M.2    Altenmüller, E.O.3
  • 44
    • 0027314774 scopus 로고
    • Identification of the visual motion area (area V5) in the human brain by dipole source analysis
    • Probst T, Plendl H, Paulus W, Wist ER, Scherg M. Identification of the visual motion area (area V5) in the human brain by dipole source analysis. Exp Brain Res 1993; 93: 345-51.
    • (1993) Exp Brain Res , vol.93 , pp. 345-351
    • Probst, T.1    Plendl, H.2    Paulus, W.3    Wist, E.R.4    Scherg, M.5
  • 45
    • 0029080930 scopus 로고
    • Shape and spatial distribution of receptive fields and antagonistic motion surrounds in the middle temporal area (V5) of the macaque
    • Raiguel S, Van Hulle MM, Xiao DK, Marcar VL, Orban GA. Shape and spatial distribution of receptive fields and antagonistic motion surrounds in the middle temporal area (V5) of the macaque. Eur J Neurosci 1995; 7: 2064-82.
    • (1995) Eur J Neurosci , vol.7 , pp. 2064-2082
    • Raiguel, S.1    Van Hulle, M.M.2    Xiao, D.K.3    Marcar, V.L.4    Orban, G.A.5
  • 46
    • 0029003587 scopus 로고
    • Topography of visual cortex connections with frontal eye field in macaque: Convergence and segregation of processing streams
    • Schall JD, Morel A, King DJ, Bullier J. Topography of visual cortex connections with frontal eye field in macaque: convergence and segregation of processing streams. J Neurosci 1995; 15: 4464-87.
    • (1995) J Neurosci , vol.15 , pp. 4464-4487
    • Schall, J.D.1    Morel, A.2    King, D.J.3    Bullier, J.4
  • 47
    • 0019505899 scopus 로고
    • Visual claustrum: Topography and receptive field properties in the cat
    • Sherk H, LeVay S. Visual claustrum: topography and receptive field properties in the cat. Science 1981; 212: 87-9.
    • (1981) Science , vol.212 , pp. 87-89
    • Sherk, H.1    LeVay, S.2
  • 48
    • 85039725907 scopus 로고    scopus 로고
    • Probing the human visual motion system by multichannel visual evoked potential (VEP) and PET scan recordings [abstract]
    • Spileers W, Cornette L, Dupont P, Joniau I, Mortelmans L, Orban GA, et al. Probing the human visual motion system by multichannel visual evoked potential (VEP) and PET scan recordings [abstract]. Vision Res 1996a; 36: S70.
    • (1996) Vision Res , vol.36
    • Spileers, W.1    Cornette, L.2    Dupont, P.3    Joniau, I.4    Mortelmans, L.5    Orban, G.A.6
  • 50
    • 33748251685 scopus 로고
    • Physical performance of the latest generation of commercial positron scanner
    • Spinks TJ, Jones T, Gilardi MC, Heather JD. Physical performance of the latest generation of commercial positron scanner. IEEE Trans Nucl Sci 1988; 35: 721-5.
    • (1988) IEEE Trans Nucl Sci , vol.35 , pp. 721-725
    • Spinks, T.J.1    Jones, T.2    Gilardi, M.C.3    Heather, J.D.4
  • 51
    • 2642603508 scopus 로고    scopus 로고
    • Many human dorsal stream regions process motion of random textured patterns [abstract]
    • Sunaert S, Van Oostende S, Van Hecke P, Marchal G, Orban GA. Many human dorsal stream regions process motion of random textured patterns [abstract]. Neuroimage 1996; 3 (3 Pt 2): S296.
    • (1996) Neuroimage , vol.3 , Issue.2-3 PART
    • Sunaert, S.1    Van Oostende, S.2    Van Hecke, P.3    Marchal, G.4    Orban, G.A.5
  • 52
    • 0030067842 scopus 로고    scopus 로고
    • Positron emission tomography study of voluntary saccadic eye movements and spatial working memory
    • Sweeney JA, Mintun MA, Kwee S, Wiseman MB, Brown DL, Rosenberg DR, et al. Positron emission tomography study of voluntary saccadic eye movements and spatial working memory. J Neurophysiol 1996; 75: 454-68.
    • (1996) J Neurophysiol , vol.75 , pp. 454-468
    • Sweeney, J.A.1    Mintun, M.A.2    Kwee, S.3    Wiseman, M.B.4    Brown, D.L.5    Rosenberg, D.R.6
  • 54
    • 0030023111 scopus 로고    scopus 로고
    • Language comprehension in language-learning impaired children improved with acoustically modified speech
    • Tallal P, Miller SL, Bedi G, Byma G, Wang X, Nagarajan SS, et al. Language comprehension in language-learning impaired children improved with acoustically modified speech [see comments]. Science 1996; 271: 81-4. Comment in: Science 1996; 271: 27-8.
    • (1996) Science , vol.271 , pp. 81-84
    • Tallal, P.1    Miller, S.L.2    Bedi, G.3    Byma, G.4    Wang, X.5    Nagarajan, S.S.6
  • 55
    • 0030023111 scopus 로고    scopus 로고
    • Tallal P, Miller SL, Bedi G, Byma G, Wang X, Nagarajan SS, et al. Language comprehension in language-learning impaired children improved with acoustically modified speech [see comments]. Science 1996; 271: 81-4. Comment in: Science 1996; 271: 27-8.
    • (1996) Science , vol.271 , pp. 27-28
  • 56
    • 0028891224 scopus 로고
    • Anatomical evidence for MT and additional cortical visual areas in humans
    • Tootell RBH, Taylor JB. Anatomical evidence for MT and additional cortical visual areas in humans. Cereb Cortex 1995; 1: 39-55.
    • (1995) Cereb Cortex , vol.1 , pp. 39-55
    • Tootell, R.B.H.1    Taylor, J.B.2
  • 57
    • 0028923891 scopus 로고
    • Functional analysis of human MT and related visual cortical areas using magnetic resonance imaging
    • Tootell RBH, Reppas JB, Kwong KK, Malach R, Born RT, Brady TJ, et al. Functional analysis of human MT and related visual cortical areas using magnetic resonance imaging. J Neurosci 1995a; 15: 3215-30.
    • (1995) J Neurosci , vol.15 , pp. 3215-3230
    • Tootell, R.B.H.1    Reppas, J.B.2    Kwong, K.K.3    Malach, R.4    Born, R.T.5    Brady, T.J.6
  • 58
    • 2642688523 scopus 로고
    • Functional analysis of human visual cortical areas V3, VP and V3A using magnetic resonance imaging [abstract]
    • Tootell RBH, Reppas JB, Rosen BR. Functional analysis of human visual cortical areas V3, VP and V3A using magnetic resonance imaging [abstract]. Hum Brain Mapp 1995b; Suppl 1: 62.
    • (1995) Hum Brain Mapp , Issue.1 SUPPL. , pp. 62
    • Tootell, R.B.H.1    Reppas, J.B.2    Rosen, B.R.3
  • 59
    • 0002651020 scopus 로고
    • Two cortical visual systems
    • Ingle DJ, Goodale MA, Mansfield RJW, editors. Cambridge (MA): MIT Press
    • Ungerleider LG, Mishkin M. Two cortical visual systems. In: Ingle DJ, Goodale MA, Mansfield RJW, editors. The analysis of visual behavior. Cambridge (MA): MIT Press, 1982: 549-86.
    • (1982) The Analysis of Visual Behavior , pp. 549-586
    • Ungerleider, L.G.1    Mishkin, M.2
  • 60
    • 0029740386 scopus 로고    scopus 로고
    • The influence of stimulus location on the brain activation pattern in detection and orientation discrimination. A PET study of visual attention
    • Vandenberghe R, Dupont P, De Bruyn B, Bormans G, Michiels J, Mortelmans L, et al. The influence of stimulus location on the brain activation pattern in detection and orientation discrimination. A PET study of visual attention. Brain 1996a; 119: 1263-76.
    • (1996) Brain , vol.119 , pp. 1263-1276
    • Vandenberghe, R.1    Dupont, P.2    De Bruyn, B.3    Bormans, G.4    Michiels, J.5    Mortelmans, L.6
  • 61
    • 0029825864 scopus 로고    scopus 로고
    • Functional anatomy of a common semantic system for words and pictures
    • Vandenberghe R, Price C, Wise R, Josephs O, Frackowiak RSJ. Functional anatomy of a common semantic system for words and pictures. Nature 1996b; 383: 254-6.
    • (1996) Nature , vol.383 , pp. 254-256
    • Vandenberghe, R.1    Price, C.2    Wise, R.3    Josephs, O.4    Frackowiak, R.S.J.5
  • 64
    • 0027460558 scopus 로고
    • Area V5 of the human brain: Evidence from a combined study using positron emission tomography and magnetic resonance imaging
    • Watson JDG, Myers R, Frackowiak RSJ, Hajnal JV, Woods RP, Mazziotta JC, et al. Area V5 of the human brain: evidence from a combined study using positron emission tomography and magnetic resonance imaging. Cereb Cortex 1993; 3: 79-94.
    • (1993) Cereb Cortex , vol.3 , pp. 79-94
    • Watson, J.D.G.1    Myers, R.2    Frackowiak, R.S.J.3    Hajnal, J.V.4    Woods, R.P.5    Mazziotta, J.C.6
  • 65
    • 0026781154 scopus 로고
    • A three-dimensional statistical analysis for rCBF activation studies in human brain
    • Worsley KJ, Evans AC, Marrett S, Neelin P. A three-dimensional statistical analysis for rCBF activation studies in human brain [see comments]. J Cereb Blood Flow Metab 1992; 12: 900-18. Comment in: J Cereb Blood Flow Metab 1993; 13: 1040-2.
    • (1992) J Cereb Blood Flow Metab , vol.12 , pp. 900-918
    • Worsley, K.J.1    Evans, A.C.2    Marrett, S.3    Neelin, P.4
  • 66
    • 0027386170 scopus 로고
    • Worsley KJ, Evans AC, Marrett S, Neelin P. A three-dimensional statistical analysis for rCBF activation studies in human brain [see comments]. J Cereb Blood Flow Metab 1992; 12: 900-18. Comment in: J Cereb Blood Flow Metab 1993; 13: 1040-2.
    • (1993) J Cereb Blood Flow Metab , vol.13 , pp. 1040-1042


* 이 정보는 Elsevier사의 SCOPUS DB에서 KISTI가 분석하여 추출한 것입니다.