Ⅰ．原著論文
(1) Saito, H., Shimahara, T. and Fukada, Y. (1970)
Four types of responses to light and dark spot
stimuli in the cat optic nerve
Tohoku J. exp. Med., 102 (2), 127-133.
Response characteristics of the previously categorized four types of cat retinal ganglion cells (ON-��,OFF-��,ON-� and OFF-�) were investigated using light and dark spot stimuli by recordings of unit discharges from the optic tract, and phasic and tonic nature of these four types of cells were further clarified. ON-�� and OFF-�� are phasic in nature and respond to only a transient increase and decrease in luminance, respectively. ON-� and OFF-�are tonic and continue to respond to a stationary light and dark contrast, respectively. Besides, a difference is also found between ON-�� and ON-� in the firing patterns of the transient response to a bright spot stimulus. ON-�� responds to the onset of a bright spot with an initial burst followed by dispersed discharges. In ON-�’s transient response, initial discharge rate is as high as that of ON-��’s burst, but in contrast with the case of ON-��’s response, the discharge rate gradually decreases toward a mean rate of sustained responses to the spot.
2) Fukada,
Y. and Saito, H. (1971)
The relationship between response characteristics to flicker stimulation and
receptive field organization in the cat's
optic nerve fibers. Vision Res., 11 (3), 227-240.
(1) The
average impulse frequency in Type ��-fibers (phasic type) increases, passes
through a maximum, and finally falls off, as the flicker frequency increases.
On the other hand, the average impulse frequency in Type�-fibers (tonic type)
remains almost unchanged over a wide range of flicker frequencies.
(2) In type��, the highest flicker frequency at which the unit responds faithfully
to individual flashes (CCF), is correlated positively with conduction velocity.
For Type� the CCF is not correlated with conduction velocity. Some Type�-units
change responsiveness during flicker stimulation, and often stop the firing for
several hundred msec.
(3) In all Type ��-fibers there is a definite relation between the CCF and the
maximum impulse frequency, while in Type� the relation between them is not
clear.
(4) The majority of Type��-fibers which had a distinct antagonistic surround in
their receptive field showed repetitive firing at high frequency (about 200 Hz)
when the flicker frequency was adjusted properly around the frequency which
elicited the maximum impulse frequency.
(5) It is concluded that Type�� is suitable for processing temporal information,
while Type� is suitable for processing spatial information.
3) Saito,
H., Shimahara, T. and Fukada, Y. (1971)
Phasic and tonic responses in the cat optic nerve fibers ―
Stimulus-response relations
Tohoku J. exp. Med.,104 (4), 313-323.
4) Fukada,
Y. and Saito, H. (1972)
Phasic and tonic cells in the cat's lateral geniculate nucleus.
Tohoku J. exp. Med., 106 (2), 209-210.
5) Fukada,
Y. and Saito, H. (1972)
Directionally selective units in the cat's lateral geniculate nucleus. In
The Visual System (ed. by Arden, G. B.),
Plenum Press, pp. 125-136.
6) Saito, H.
and Fukada, Y. (1973)
Repetitive firing of the cat's retinal ganglion cell
Vision Res., 13 (2), 263-270.
The induced activity which was previously found to be elicited by flickering lightspots in Type-�歡ells (phasic cells) of the cat’s retina could also be elicited by diffuse flicker and by repetitive antidromic stimulation of the ganglion cell. This activity was elicited when the ganglion cell was activated at high frequency for long period (at 120-250 impulses/sec for about 1min), and lasted for about 1min with regularly-spaced high frequency discharges (initial frequency, 100-200 impulses/sec) and suddenly ceased when the discharge rate reduced monotonically to about a half. For Type-�cells (tonic cells), either the flickering light stimulation or the repetitive antidromic stimulation of the cells failed to elicit induced activity. The above differences could reflect the differences in the receptive field organization between Type-�歛nd Type-�cells.
7) Saito, H.
and Fukada, Y. (1975)
Gain control mechanisms within the receptive field center of cat's retinal
ganglion cells
Vision Res., 15 (12), 1407-1410.
8) 斎藤 秀昭
(1976)
網膜神経節細胞の受容野における抑制機構。
日本生理学雑誌 38 (12), 489-502.
9) Saito, H.
(1981)
The effects of strychnine and bicuculline on the responses of X- and Y-cells
of the isolated eye-cup preparation of the cat
Brain Res., 212 (1), 243-248.
Key words: inhibitory mechanism ― receptive field ― X, Y retinal ganglion cell ― drug effect ― isolated eye-cup―cat
The effects of strychnine and bicuculline, the respective antagonists of glycine and GABA, on the inhibitory responses of X- and Y-type retinal ganglion cells of the cat were investigated using an isolated eye-cup preparation. The surround inhibition of the on-center X-cell was blocked by strychnine, whereas that of the on-center Y-cell was blocked by bicuculline. In the case of the off-center cells, bicuculline indifferently blocked the center and the surround responses of either the X-cell or the Y-cell, but strychnine did not.
10) Saito,
H. (1982)
Pharmacological differences in the surround mechanism between on-center X-
and Y-cells of the excised and perfused eye-cup preparations of the cat
Biomedical Res., 3, Suppl., 79-82.
11) Saito,
H. (1983)
Morphology of physiologically identified X-, Y-, and W-type retinal ganglion
cells of the cat.
J. Comp. Neurol., 221 (3), 279-288.
Retinal ganglion cells of the cat have been classified physiologically into X-,
Y,- and W-cells, on the basis of the receptive field properties, and
morphologically into α-, β-, and γ-cells.
In order to study directly the correspondence between these classifications,
intracellular recordings from the ganglion cells in superfused eye-cup
preparations were made with the aid of microelectrodes filled with Lucifer
yellow CH. The cells were stained after their photic responses were studies
under mesopic adaptation.
X-cells, showing sustained depolarization (on-center cells) or
hyperpolarization (off-center cells) in response to a spot of light had
medium-sized round somata and spread bushy dendrites within a narrow retinal
area. On the other hand, on-center and off-center Y-cells, showing transient
responses to the spot stimulus, had large somata and widely expanded thick
dendrites which were sparsely branched. W-cells which showed weak sustained
responses had widely extended thin and winding dendrites, despite a small somal
size. These morphological features of Y-, X-, and sustained W-cells correspond
well to those ofα-, β-, and δ-cells (a subtype of γ-cells), respectively. The
hypothesis of “morphology reflecting function”is strongly supported.
Key words: X-cell, Y-cell, W-cell, function, intracellular staining
12) Saito, H. (1983)
Pharmacological and morphological differences between X- and Y-type ganglion
cells in the cat's retina.
Vision Res., 23 (11),1299-1308.
13) 小山田 浩 *、田中
啓治、斎藤 秀昭、深田 芳郎 （1985, March） *印 東北大工
図形識別の基礎をなすネコ１９野細胞の受容野特性。
信学技報、BME84 (257), 39-46.
14) 野中 かお美 +、塚田
稔 +、彦坂 和雄 *、靭負 政雄 *、岩井 栄一 *、
田中 啓治、斎藤 秀昭、深田 芳郎 （1985, March） +印 玉川大工、*印（財）東京神経研・医学心理
上側頭溝皮質ニューロンの受容野特性と応答性。
信学技報、MBE84 (257), 33-38.
15) 小山田 浩 *、田中
啓治、斎藤 秀昭、深田 芳郎、 木村 政行 *（1986, March）*印 東北大工
図形識別におけるネコ１７、１９野細胞の果たす役割。
信学技報、MBE85 (331), 165ー174.
16) Saito,
H. and Fukada, Y. (1986)
Gain control mechanisms in X- and Y-type retinal ganglion cells of the cat.
Vision Res., 26 (3), 391-408.
A change in
responsiveness caused by a spot of light (conditioning spot, CS; 3 sec in
duration) presented within a central region of the receptive field of X-and
Y-type retinal ganglion cells of the cat was investigated by measuring the
magnitude of responses to another spot of light (test spot, TS; 50 msec in
duration) which was juxtaposed with the CS within the same receptive field’s central region.
Responses to the TS were suppressed steadily during the on-phase of the CS as
if it were divided by a certain value. This fact indicates that the gain of the
center mechanism was changed by the CS presentation. The setting of the gain to
a new level was rapid (within 100 msec after the onset or the cessation of the
CS), and the magnitude of a gain change was not affected by the surround
antagonism. These characteristics of the gain control were common to X- and
Y-cells under both mesopic and scotopic levels of light adaptation.
Key words: Gain control, Sensitivity, Receptive field, Retina, Ganglion cell ,
X-cell, Y-cell, Cat
17) Tanaka,
K., Hikosaka, K., Saito, H., Yukie, M., Fukada, Y. and Iwai, E. (1986)
Analysis of local and wide-field movements in the superior temporal visual areas
of the macaque monkey.
J. Neurosci., 6 (1), 134-144.
The middle temporal (MT) and medial superior temporal (MST) areas of the
macaque cortex have many cells that respond to straight movements in the
frontoparallel plane with directional selectivity (D cells). We examined their
responses to movements of a bar, of a wide dot pattern, and to combined
movements of the two in anesthetized and immobilized animals. D cells in MT
showed a wide variety in the strength of the inhibitory field surrounding the excitatory
center field. Responses of SI＋-type cells to a bar moving across the excitatory
field were suppressed when a wide dot pattern moved over the surround field in
the same direction and at the same speed as the bar. Inhibition was selective
to the direction and speed of the surround movement, and the effective area for
inhibition occupied a wide area, which expanded in all radial directions.
Responses of SI－-type cells to a center bar movement were changed little by a
conjoint movement over the surround field. Consequently, SI－-type cells
responded to wide-field movement as well as to stimuli confined within the
excitatory field. Although D cells in MST commonly had large excitatory fields,
a proportion of them (Figure type) responded to bar movement much more strongly
than to wide field movement. Their responses to a bar movement were suppressed
direction-selectively by a conjoint movement of a wide dot-pattern background.
The effective area for inhibition coexisted with the excitatory field in these
cells. MST cells of the Nonselective type responded comparably well to the two
stimuli, and those of the Field type responded much more strongly to wide-field
movement than to bar movement. It is thus suggested that MT cells of the SI＋
type and MST cells of the Figure type can detect a difference between movements
of an object and its wide background, whereas MST cells of the Field type can
detect a conjoint movement of a wide field, neglecting the movements of a
single object.
18) Saito,
H., Yukie, M., Tanaka, K., Hikosaka, K., Fukada, Y. and Iwai, E. (1986)
Integration of direction signals of image motion in the superior temporal
sulcus of the macaque monkey.
J. Neurosci., 6 (1), 145-157.
Using anesthetized and paralyzed monkeys, we have studied the visual response properties of neurons in the cortical area surrounding the middle temporal area (MT) in the superior temporal sulcus (STS). Systematic electrode penetrations revealed that there is a functionally distinct region where three classes of directionally selective cells with large receptive fields cluster. This region is anteriorly adjoined to the dorsal two-thirds of MT, has a width of 4-5mm mediolaterally, and therefore may correspond to the dorsal part of the medial superior temporal area (MST), which was previously defined as a MT-recipient zone. One class of cells responded to a straight movement of patterns in the frontoparallel plane with directional selectivity (D cells: 217/422, 51.4%). The second class of cells selectivity responded to an expanding or contracting size change of patterns (S cells: 66/422, 15.7%). These cells responded neither to a change in width of a slit of any orientation or any length, nor to a change in brightness. The third class of cells responded only to a rotation of patterns in one direction (R cells: 58/422, 13.7%). A majority of these cells (41/58) responded to the clockwise or counterclockwise rotation of patterns in the frontoparallel plane (Rf cells), while the rest responded to a rotation of patterns in depth (Rd cells). We will suggest that those cells acquire the ability to discover whole events of visual motion―i.e., unidirectional straight movement, size change (radial movement), and rotation―by integrating elemental motion information extracted by MT cells. The receptive fields of D,S, and Rf cells can be constructed by converging signals of MT cells, the preferred directions of which are arranged in parallel (D cells), radially (S cells), and circularly (Rf cells). The receptive fields of Rd cells can be constructed, in turn, by the convergence of signals of S cells.
19) 斎藤 秀昭、田中
啓治、磯野 春雄、安田 稔、三上 章允 * （1987, March） *印 京大霊長研
視覚中枢ＭＴ野の細胞は等輝度色度パターンの動きを分析できるか。
信学技報、MBE86 (400), 227-232.
20) Saito,
H., Tanaka, K., Fukada, Y. and Oyamada, H. (1988)
Analysis of discontinuity in visual contours in area 19 of the cat
J. Neurosci., 8 (4), 1131-1143.
Previous ablation studies have suggested that area 19 of the cat plays an
important role in pattern discrimination. To clarify the function roles unique
to area 19, we studied the receptive-field properties of cells in area 19 and
compared them with those of cells in area 17.
Recordings were mode of anesthetized and immobilized animals. The majority
(72%) of the cells in area 17 responded maximally to an elongated bar at a
particular orientation, while they responses only weakly or not at all to a
small spot (elongation-requiring cells). In contrast, more than half (63%) of
the cells in area 19 showed a good response to a nonoriented small stimulus
moving in any direction (dot-responsive cells). Two-thirds of the
dot-responsive cells in area 19 failed to respond when the moving slit was
elongated to more than some length in any orientation. These dot-responsive
cells of the “inhibited-by-length” type responded strongly to the end of a long
bar, and many of them also responded strongly to a break point in the middle of
a long bar. We suggest that these dot-responsive cells of the “inhibited-by-length”
type detect discontinuities in contours.
Though they are in the minority, elongation-requiring cells constitute a
considerable population (37%) in area 19, and dot-responsive and
elongation-requiring cells form columnar patches in the same area. We conclude
that, in contrast to area 17, whose main role is the decomposition of patterns
into oriented contours, area 19 analyzes both orientation and discontinuities,
with a strong bias towards the latter.
21)
Hikosaka, K., Iwai, E., Saito, H. and Tanaka, K. (1988)
Polysensory properties of neurons in the anterior bank of the caudal
superior temporal sulcus of the macaque monkey
J. Neurophysiol., 60 (5), 1615-1637
1. We
examined the sensory properties of cells in the anterior bank of the caudal
part of the superior temporal sulcus (caudal STS) in anesthetized, paralyzed
monkeys to visual, auditory, and somesthetic stimuli.
2. In the anterior bank of the caudal STS, there were three regions
distinguishable from each other and also from the middle temporal area (MT) in
the floor of the STS and area Tpt in the superior temporal gyrus. The three
regions were located approximately in the respective inner, middle, and outer
thirds of the anterior bank of the caudal STS. These three regions are referred
to, from the inner to the outer, as the medial superior temporal region (MST),
the mostly unresponsive region, and the caudal
STS polysensory region (cSTS), respectively.
3. The extent of MST and its response properties agreed with previous studies.
Cells in MST responded exclusively to visual stimuli, had large visual
receptive fields (RFs), and nearly all (91%) showed directional selectivity.
4. In the mostly unresponsive region, three quarters of cells were unresponsive
to any stimulus used in this study. A quarter of the cells responded to only
visual stimuli and most did not show directional selectivity for moving
stimuli. Several directionally selective cells responded to movements of
three-dimensional objects, but not of projected stimuli.
5. The response properties of cells in the superficial cortex of the caudal
superior temporal gyrus, a part of area Tpt, external to cSTP were different
from those of cells in the three regions in the anterior bank of the STS. Cells
in Tpt were exclusively auditory, and had much larger auditory RFs (mean=271°)
than those of acoustically-driven cSTP cells (mean = 138°).
6. The cSTP contained unimodal visual, auditory, and somesthetic cells as well
as multimodal cells of two or all three modalities. The sensory properties of
cSTP cells were as follows.
1) Out of 200 cells recorded, 102 (51%) cells were unimodal (59 visual, 33
auditory, and 10 somesthetic), 36 (18%) cells were bimodal (21 visual＋auditory,
7 visual＋somesthetic, and 8 auditory＋somesthetic), and four (2%) cells were
trimodal. Visual and auditory responses were more frequent than somesthetic
responses; the ratio of the population of cells driven by
visual:auditory:somesthetic stimuli was 3:2:1.
2) Visual RFs were large (mean diameter, 59°), but two-thirds were limited to
the contralateral visual hemifield. About half the cells showed directional
selectivity for moving visual stimuli. None showed selectivity for particular
visual shapes.
3) Auditory RFs were large and mostly located in the contralateral hemifield.
Most cells responded similarly to several auditory stimuli, such as pure tones,
white noise, human voices, and hand clapping, although a few cells showed
selectivity for complex sound. Few cells were selective for moving auditory
stimuli.
4) Somesthetic responses were evoked by cutaneous stimuli, such as a light
touch on the skin and bending single hairs. Samesthetuc RFs were large and
mostly located on the dorsal surface of the trunk. Most cells were not
selective for moving somesthetic stimuli
5) For most visual＋auditory cells, the visual RFs were included in the auditory
RFs (overlapping type). For other visual＋auditory cells, the auditory RFs were
juxtaposed to the periphery of the visual RFs (complementary type).
6) The overlapping and complementary organizations of RF positions were also
found in the combination of somatosensory input with visual and/or auditory
inputs. Cells of the overlapping type had the somesthetic RFs on the surface of
the body fronting on the external space where their visual and/ or auditory RFs
were located. By contrast, cells of the complementary type had the somesthetic
RFs on the surface of the body not fronting on their visual and/or auditory
RFs.
7) A small number of multimodal cells showed analogous selectivity across
stimulus modalities. For example, a visual＋somesthetic cell exhibited a matched
directional selectivity for the movements of visual and somesthetic stimuli.
8) The findings suggest that cSTP is involved in global attention, but not in
focal attention nor in object recognition.
22) Saito,
H., Tanaka, K., Isono, H., Yasuda, M. and Mikami, A. (1989)
Directionally selective response of cells in the middle temporal area (MT)
of the macaque monkey to the movement of equiluminous opponent color stimuli
Exp. Brain Res., 75, 1-14.
Based on the
fact that a great majority of cells in the middle temporal (MT) area of the
macaque respond to movement of luminance contours with directional selectivity,
this area has been thought to be concerned with the analysis of visual motion.
However, objects can be discriminated from the background not only by
differences in luminance but also by differences in color. It is possible that
color signals are also used for motion analysis in MT. In the present study, we
examined whether MT cells respond to movement of a pattern composed of pure
color-contours. Using a color TV system, a moving color bar was displayed on a
uniform background whose color was opponent with that of the bar. The main
bar/background color combination we examined was magenta/cyan. Yellow/blue and
cyan/magenta combinations were also examined for some cells. The response of MT
cells to movements of opponent-color stimuli was recorded while the
bar/background luminance ratio was changed from 1/10 to 10/1. In half of 89
cells tested in 3 monkeys, the response decreased considerably (disappeared
completely in some cells) at a luminance ratio close to the human equiluminous
condition. In the other half, a directional response persisted at any
bar/background luminance ratio, though the response decreased to a varied
extent (30-90% of the maximum response) near the ratio 1 (human equiluminous
condition). The average magnitude of the equiluminous response to the
magenta/cyan stimulus for the overall population was about 35% of the maximal
response when the length of the bar (0.5°in width) and the movement amplitude
were set to be optimal for individual cells, i.e. smaller than 15° and 10°of
visual angle, respectively. This fall to 23% when the bar length and movement
amplitude were limited to 2°. The same cell responded to pure color-contours of
yellow/blue as well as of cyan/magenta combinations. Thus, MT can detect the
direction of movement of pure color-contours, although the sensitivity is less
than for luminance contours.
Key words: Middle temporal (MT) area , Visual motion analysis , Directional
selectivity , Color contour ミ Monkey
23) Tanaka,
K. and Saito, H. (1989)
Analysis of motion of the visual field by Direction, Expansion/Contraction,
and Rotation cells clustered in the dorsal part ofthe medial superior temporal
area of the macaque monkey.
J. Neurophysiol., 62 (3), 626-641.
24) Tanaka,
K., Fukada, Y. and Saito, H. (1989)
Underlying mechanisms of the response specificity of Expansion /Contraction
and Rotation cells in the dorsal part of the medial
superior temporal area of the macaque monkey.
J. Neurophysiol., 62 (3), 642-656.
1. The
dorsal part of medial superior temporal area (MST) has two unique types of
visually responsive cells: 1) expansion/contraction cells, which selectively
respond to either an expansion or a contraction; and 2) rotation cells, which
selectively respond to either a clockwise or a counterclockwise rotation. In
addition to selectivity for the mode of motion, both types of cells respond
preferentially to movements over a wide field rather than over a small field.
With the aim of understanding the underlying mechanisms of these selectivities,
we carried out experiments on immobilized monkeys anesthetized with N2O.
2. Expansion/contraction and rotation of a pattern extending over a wide field
contain three stimulus factors: 1) the spatial arrangement of different
directions of movement, 2) the gradient in the speed of regional movement from
the center to the periphery of the stimulus, and 3) the size change of texture
components of the pattern in the expansion/contraction and the acceleration of
movement of texture components toward the center of the stimulus in the
rotation. The contribution of each factor to the activation of the cells was
evaluated by comparing the response before and after removing the factor from
the stimulus. The moving stimuli that lacked one or two of the factors were
produced by the use of a cinematographic animation technique.
3. Withdrawal of the first factor, the spatial arrangement of different
directions of movement, reduced the response of both Expansion/contraction and
Rotation cells much more severely than either of the other two factors. We
conclude that the first factor is far more important for activation than the
other two.
4. These results are consistent with the model that Expansion/contraction and
Rotation cells receive converging inputs from many directional cells with
relatively small receptive fields in different parts of the visual field.
Because MST receives strong fiber projections from MT, MT cells are candidates
for the input cells. According to the model, if the convergence is organized so
that the preferred directions of the input cells are arranged radially, the
target cell will be an Expansion/contraction cell; if the input cells are
arranged circularly, a Rotation cell will result.
25) 中嶋 浩、水野 真、樋田
栄揮、斎藤 秀昭、塚田 稔 （1990, March ）
ランダムチェッカーパターンの統一的動きの確率と広視野運動知覚の関係
信学技報、 NC89 (463), 159-164.
26) Tanaka,
K., Saito, H., Fukada, Y. and Moriya, M. (1991)
Coding visual images of objects in the inferotemporal cortex of the macaque
monkey.
J. Neurophysiol., 66 (1), 170-189.
1. The
inferotemporal cortex (IT) has been thought to play an essential and specific
role in visual object discrimination and recognition, because a lesion of IT in
the monkey results in a specific deficit in learning tasks that require these
visual functions. To understand the cellular basis of the object discrimination
and recognition processes in IT, we determined the optimal stimulus of
individual IT cells in anesthetized, immobilized monkeys.
2. In the posterior one-third or one-fourth of IT, most cells could be
activated maximally by bars or disks just by adjusting the size, orientation,
or color of the stimulus.
3. In the remaining anterior two-thirds or three-quarters of IT, most cells
required more complex features for their maximal activation.
4. The critical feature for the activation of individual anterior IT cells
varied from cell to cell: a complex shape in some cells and a combination of
texture or color with contour-shape in other cells.
5. Cells that showed different types of complexity for the critical feature
were intermingled throughout anterior IT, whereas cells recorded in single
penetrations showed critical features that were related in some respects.
6. Generally speaking, the critical features of anterior IT cells were
moderately complex and can be thought of as partial features common to images
of several different natural objects. The selectivity to the optimal stimulus
was rather sharp, although not absolute. We thus propose that, in anterior IT,
images of objects are coded by combinations of active cells, each of which
represents the presence of a particular partial feature in the image.
27) Saito,
H., Mizuno, M., Nakajima, H. Kaneko, M. Hida, E. and Tsukada, M.(1991)
A high degree of noise tolerance in human visual flow discriminaiton.
Artificial Neural Networks, North-Holland., Vol.2,
1397-1400.
28) Saito,
H., Mizuno, M., Nakajima, H. Kaneko, M. Hida, E. and Tsukada, M.(1991)
Response of directionally selective cells of the macaque dorsal MST area to
visual flow with directional noise and its relation to the noise tolerance in
human visual flow discrimination.
Artificial Neural Networks, North-Holland., Vol.2,
1401-1404.
29) Tanaka,
K., Sugita, Y., Moriya, M. and Saito, H. (1993)
Analysis of object motion in the ventral part of the medial superior
temporal area of the macaque visual cortex.
J. Neurophysiol., 69 (1), 128-142.
1. The
medial superior temporal area (MST) is an extrastriate area of the macaque
visual cortex. Cells in MST have large receptive fields and respond to moving
stimuli with directional selectivity. We previously suggested that the dorsal
part of MST is mainly involved in analysis of field motion caused by movements
of the animal itself, because most cells in the dorsal part preferentially
responded to movements of a wide textured field rather than to movements of a
small stimulus. To determine whether the remaining ventral part of MST differs
in function from the dorsal part, we examined properties of cells in the
ventral part in comparison with those of cells in the dorsal part, using
anesthetized and paralyzed preparation.
2. Most cells in the ventral part preferably responded to movements of a small
stimulus rather than to movements of a wide textured field.
3. Although the cells in the ventral part did not respond to movements of a
textured field over a large window, many of them began to respond when a small
stationary object was introduced in front of the moving field. The direction to
which the cells responded in this stimulus configuration was opposite to the
direction in which they responded to movements of an object on a stationary
background. Activities of these cells thus represented the direction of
relative movement of an object on a background, irrespective of whether the
image of the object or the background moved on the retina.
4. We conclude that the ventral part of MST is distinctive from the dorsal part
of MST and is mainly involved in the analysis of object movements in external
space.
30) 斎藤 秀昭、樋田
栄揮、長尾 秀格、金井 邦光 (1994)
マカクザル視覚野における階層位置による脳内情報表現の安定性の相違。
信学技報、NC94 (129), 63-68.
31) 斎藤 秀昭、樋田
栄揮、塚田 稔、水野 真、森 晃徳 (1995)
広視野運動の認知特性とＭＳＴ野細胞の反応特性の対応。
玉川大学工学部紀要、30, 145-149.
32) 倉地 洋介、大野
裕史、佐藤 祥子、中野 潤、羽田 茂、樋田 栄揮、斎藤秀昭 (1996)
広視野運動認知における２方向重畳刺激の影響。
信学技報、NC95 (599), 239-246.
33) 大野 裕史、赤司
牧子、堤 啓三、中尾 充男、成田 誠、樋田 栄揮、斎藤秀昭 (1996)
運動認知に関わる神経細胞の反応の大きさと運動速度認知との関連。
信学技報、NC95 (599), 247-254.
34) Tsukada,
M., Aihara, T., Saito, H. and Kato, H. (1996)
Hippocampal LTP depends on spatial and temporal correlation of inputs.
Neural Networks, 9 (8), 1357-1365.
We studied
the LTP inducing factors using temporally and spatially modulated stimuli given
to the hippocampal neural network. It was found that when the spatial factors
were maintained to be constant the positive correlation in the successive
inter-stimulus intervals contributes to produce larger LTP. On the other hand,
if the temporal factors are kept constant, the spatial coincidence contributes
to produce larger LTP. We propose a learning rule by which these experimental
results can be consistently interpreted.
Key words: LTP, Hippocampus, Spatio-temporel stimuli, Learning rule, Optical
recording
35) 小田島桂一、入江真太郎、小野田昌弘、平井貴子、玉野井太智、樋田
栄揮、斎藤秀昭 (1997)
２方向重畳 Visual-Flow の心理的認知特性とその基礎となる神経過程。
信学技報、NC97-20, 73-78.
36) 秦奈緒美、二方明、向山重徳、小田島桂一、樋田
栄揮、斎藤秀昭 (1997)
視覚的フィリングインにおける色、形、動きの効果。
信学技報、NC97-21, 79-82.
37) Saito,
H., Hida, E., Ohno, H., Odajima, K. and Tamanoi, D. (1997)
Perception of visual flow composed of texture of different attributes and
its neural representation. In: Progress in
Connectionist-Based Information Systems. (Proc.
ICONIP'97-Dunedin), Springer, Vol.1, 10-13.
38) Nomura,
M., Hida, E., Odajima, K., Tamanoi, D., and Saito, H. (1998)
Area MT cells detect an illusory line motion.
IOVS (Investi. Ophthalmol. Visual Sci.) 39 (4),
S904.
39) Okamoto,
H., Kawakami, S., Saito, H., Hida, E., Odajima, K., Tamanoi, D., and Ohno, H.
(1998)
Physiological validation of bimodal direction tunings predicted by a motion
detection model in area MT of monkey.
Proceed. ICONIP'98, Vol. 3, 1422-1425.
40) Hida,
E., Saito, H., Ohno, H., Odajima, K., and Tamanoi, D. (1998)
Neural correlate for the perception of two-directional transparent visual
flow.
Proceed. ICONIP'98, Vol. 3, 1551-1554.
41) Okamoto,
H., Kawakami, S., Saito, H., Hida, E. (1998)
Macaque MT neurons exhibit two types of bimodality in direction tunings.
Society For Neurosci. Abstract '98, Part 2, 1745.
42) Okamoto,
H., Kawakami, S., Saito, H., Hida, E., Odajima, K., Tamanoi, D., Ohno, H.(1999)
MT neurons in the macaque exhibited two types of bimodal direction tuning as
predicted by a model for visual motion detection
Vision Research., 39. 3465-3479
We previously proposed a model for detecting local image velocity on the
magnocellular visual pathway (Kawakami & Okamoto (1996) Vision Research, 36, 117-147). The model detects visual motion in two stages using
the hierarchical network that includes component and pattern cells in area MT.
To validate the model, we predicted two types of bimodal direction tuning for
MT neurons. The first type is characteristic of component cells. The tuning is
bimodal when stimulated with high-speed spots, but unimodal for low-speed spots
or for bars. The interval between the two peaks widens as the spot’s speed
increases. The second type is characteristic of pattern cells. The tuning is
bimodal when stimulated with low-speed bars, but unimodal for high-speed bars
or for spots. The interval widens as the bar’s speed decreases. To
confirm this prediction, we studied the change of direction tuning curves for moving
spots and bars in area MT of macaque monkeys. Out of 35 neurons measured at
various speeds, six component cells and four pattern cells revealed the
predicted bimodal tunings. This result provided neurophysiological support for
the validity of the model. We believe ours is the first systematic study that
records the two types of bimodality in MT neurons.
Key words: Network model; Local image velocity; Bimodal direction tuning:
Single cell response; Area MT
43) 重原隆一朗、橋本直樹、大野裕史、樋田栄揮、斎藤秀昭
(2000)
二次運動に対するマカクザルのMST細胞の反応
信学技報、NC99-158, 61-68.
44) 橋本直樹、斎藤秀昭、樋田栄揮、大野裕史（2001)
立体的視覚フローに対するマカクザルMST野細胞の反応
信学技報、NC2001-13, 27-31.
45) 斎藤秀昭、樋田栄揮（2001)
Visual flow の認知特性と脳内神経情報表現
玉川大学学術研究所紀要、7, 85-97.
46) 大野裕史，橋本直樹，樋田栄揮，斎藤秀昭
(2002)
MST野細胞集団の活動プロフィルによるvisual flowおよびその運動残効認知の情報表現
日本神経回路学会誌, Vol.9, No.1, 4-15
We propose a hypothesis 'population representation of visual flow by the
activity profile of MST cells', which assumes that the perception of all kinds
of visual flow (uniform translation, rotation, approaching, receding, etc.) and
of motion aftereffects caused by them would be directly related to the
activity-profile of the cells in the dorsal part of the MST area.
In order to test this hypothesis, we investigated properties of both visual
flow perception and the motion aftereffect (by psychophysical experiments on
human subjects), and compared with MST cells' activities measured during and
after giving various flow stimuli (by single cell recordings from anaesthetized
monkeys).
We have confirmed that we perceive characteristic motion aftereffect the
direction of which was opposite to the adapting stimuli; for example,
perception of counter-clockwise rotation against a stationary texture-field
after receiving a flow of clockwise rotation.
MST cells, which responded selectively to the particular mode of visual flow,
reduced their activities after receiving the prolonged flow stimulus moving in
the preferred direction, whereas increased their activities after receiving the
flow moving in the opposite direction. These response properties strongly
support proposed hypothesis.
We can interpret the properties of the perception of a transparent visual flow
(superposition of two translations of different directions) and of its motion
aftereffect with the 'population representation hypothesis', consistently, by
assuming the existence of two sub-types, named 'component type' and
'integration type', in MST cells responding selectively to the translational
flow. The existence of the two sub-types was verified in our present experiments.
47) 大野裕史，橋本直樹，樋田栄揮，斎藤秀昭
(2002)
立体的visual flowに対するマカクザルMST野細胞の反応
日本神経回路学会誌, Vol.9, No.4, 215-223
Three-dimensional visual flow caused by self-movements provides important cues
for the perception of space, and thus for the perception and control of own
movement.
At least 3 depth-cues built up by moving elements are contained in such a
flow. One is purely dynamic signal independent of a visual pattern of a facing
scene, i.e., 'speed-gradient'. The other two are rather static signal called
'perspective', i.e., 'size-gradient' and 'density-gradient' in a texture
pattern.
We investigated relative contribution of the three cues for the perceptual
impression of 3-dimensional space by presenting computer-generated virtual flow
stimuli in which the three cues are controlled independently. As expected, the
contribution of speed-gradient was most strong, a medium was texture
size-gradient, and the weakest was texture density-gradient.
We also investigated response-properties of cells in macaque MST-area using similar
stimuli. MST cells are classified into three groups according to the different
response-behaviors to 2-dimensional and 3-dimensional visual flow. Based on
these results, a psychology-physiology correspondence is suggested.
48) 大野裕史，橋本直樹，樋田栄揮，斎藤秀昭
(2003)
MST野細胞集団の活動分布形によるvisual flowおよびその運動残効認知の情報表現
信学技報,
NC2002-227 (2003-03), 143-148
We propose a hypothesis 'population representation of visual flow by the activity profile of MST cells', which assumes that the perception of all kinds of visual flow and of motion aftereffects caused by them would be directly related to the activity-profile of the cells in the dorsal part of the MST area. In order to test this hypothesis, we investigated properties of both visual flow perception and the motion aftereffect, and compared with MST cells’ activities measured during and after giving various flow stimuli.
Ⅱ．解説
1) 斎藤 秀昭
(1969)
生体の視覚情報処理機構をさぐる。 ＮＨＫ技研月報、12 (5), 223-228.
2) 斎藤 秀昭 (1977)
視覚。 TOKICO REVIEW、21 (2), 6-10.
3) 斎藤 秀昭 (1983)
網膜における情報処理のメカニズム。 ＮＨＫ技研月報、24 (4), 140-148.
4) 斎藤 秀昭 (1984)
網膜神経節細胞における機能と形態の対応。 神経眼科、 1 (1), 31-33.
5) 斎藤 秀昭、田子島一郎 (1984)
網膜の構造と機能 ― ３次元個体イメージセンサ実現への示唆 ―
信学誌、67 (8), 881-885.
6) 斎藤 秀昭 (1985)
視覚系の神経ネットワークと情報処理。 応用物理、54 (4), 331-337.
7) 斎藤 秀昭、深田 芳郎 (1985)
パターン認識の基礎となる神経過程の解明 ― 網膜の神経回路と並列情報処理 ―
ＮＨＫ技術研究、 37 (2), 81-98.
8) 斎藤 秀昭 (1986)
網膜における情報処理 ― 神経節細胞の機能的・形態的分類と軸索の中枢投射 ―
神経進歩、30 (1), 184-198.
9) 斎藤 秀昭 (1986)
パターン知覚の神経機構。 テレビ誌、40 (4), 256-265.
10) 斎藤 秀昭 (1986)
網膜・インテリジェント光センサー。 Trigger, 86 (10), 29-32.
11) 斎藤 秀昭 (1987)
視覚。 日本臨牀、45 (9), 28-39.
12) 斎藤 秀昭 (1988)
視覚情報処理に関する生理学的知見と展望。 テレビ学技報、12 (14), 19-24.
13) 斎藤 秀昭
(1989)
視覚神経系の構造とその情報処理。 情報処理、30 (2), 114-128.
14) 斎藤 秀昭
(1992)
脳における視覚的運動の階層処理。 医学のあゆみ、161 (11), 847-850.
15) 斎藤 秀昭
(1994)
知覚・認知と脳の細胞活動はどう対応するか。 実験医学、12 (15),2553-2560.
16) 斎藤 秀昭、 樋田
栄揮 (1997)
視覚的空間認知の脳内機構。 玉川大学学術研究所紀要、第３号、111-115.
Ⅲ．著書
1) 斎藤 秀昭 (1987)
「視聴覚系の神経機構」 樋渡 涓二 編著、視聴覚情報概論、編、151-238. （昭晃堂）
2) 斎藤 秀昭 (1989)
「脳での視覚情報処理」 日本物理学会 編、生物物理のフロンティア、
第部６章、 274-286. （培風館）
3) 斎藤 秀昭
(1989)
「脳における視覚・聴覚の情報処理 ―その基本思想―」
松本 元 編、バイオエレクトロニクス、Maruzen Advanced Technology、
電子・情報・通信編、３章、103-145. （丸善）
4) Hide-aki
Saito (1993)
Hierarchical Neural Analysis of Optical Flow in the Macaque Visual Pathway.
In Brain Mechanisms of Perception and Memory.
Ed. by T. Ono, L.R.Squire, M.E. Raichle, D.I. Perrett & M. Fukuda,
(Oxford University Press)
5) 斎藤 秀昭
(1996, March)
「視覚・聴覚情報の認知過程」
松本 元 編、脳・心・コンピュータ、２章２節、123-137. （丸善）
6) 斎藤秀昭、森 晃徳 編 （1999,
Feb.）
「視覚認知と聴覚認知」 （オーム社）
7) 斎藤秀昭（2001)
「視覚の心理現象と神経活動」
福島邦彦、大串健吾、斎藤秀昭 共著 「視聴覚情報処理」３章、14-63. (森北出版)
Ⅳ．訳本
1) 斎藤 秀昭
(1989)
「大脳皮質の構造と機能」（F. Crick and C. Asanuma 著）
D. E. Rumelhart, J. L. McClelland, and PDP Research Group 著、
甘利 俊一 監訳、ＰＤＰモデル 認知科学とニューロン回路網の探索、
第１０章、421-464. （産業図書）
Ⅴ．その他
1) 斎藤 秀昭 (1988)
ＮＨＫ放送技術研究所・視覚情報研究部 神経生理学部門 小史
日生誌
2) 斎藤 秀昭
(1988)
「視覚神経系の構造と機能」
電子情報通信ハンドブック、第１２編、第１部門、1075-1081.
（オーム社）
3) 斎藤 秀昭
(1994)
「脳の構造と機能」
ニューロ・ファジィ・ＡＩハンドブック、１編、３章、10-14.
計測自動制御学会編、（オーム社）
Cognitive Engineering Laboratory,Tamagawa University
hohno@lab.tamagawa.ac.jp