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144
Distributed hierarchical processing in the primate cerebral cortex
- Cereb Cortex
, 1991
"... In recent years, many new cortical areas have been identified in the macaque monkey. The number of identified connections between areas has increased even more dramatically. We report here on (1) a summary of the layout of cortical areas associated with vision and with other modalities, (2) a comput ..."
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Cited by 928 (6 self)
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In recent years, many new cortical areas have been identified in the macaque monkey. The number of identified connections between areas has increased even more dramatically. We report here on (1) a summary of the layout of cortical areas associated with vision and with other modalities, (2) a computerized database for storing and representing large amounts of information on connectivity patterns, and (3) the application of these data to the analysis of hierarchical organization of the cerebral cortex. Our analysis concentrates on the visual system, which includes 25 neocortical areas that are predominantly or exclusively visual in function, plus an additional 7 areas that we regard as visual-association areas on the basis of their extensive visual inputs. A total of 305 connections among these 32 visual and
The ‘‘shared manifold’’ hypothesis: from mirror neurons to empathy
- Journal of Consciousness Studies
, 2001
"... We are social animals. We share this feature with many other species. A complexity and sophistication that we do not observe among ants, bees or wolves, however, characteristically define the social life of primates. This complexity and sophistication is epitomized at its highest level by the social ..."
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Cited by 129 (16 self)
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We are social animals. We share this feature with many other species. A complexity and sophistication that we do not observe among ants, bees or wolves, however, characteristically define the social life of primates. This complexity and sophistication is epitomized at its highest level by the social rules our conduct in everyday life is supposed
Retinotopy and functional subdivision of human areas MT and MST
- JOURNAL OF NEUROSCIENCE
, 2002
"... We performed a series of functional magnetic resonance imaging experiments to divide the human MT � complex into subregions that may be identified as homologs to a pair of macaque motion-responsive visual areas: the middle temporal area (MT) and the medial superior temporal area (MST). Using stimuli ..."
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Cited by 70 (2 self)
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We performed a series of functional magnetic resonance imaging experiments to divide the human MT � complex into subregions that may be identified as homologs to a pair of macaque motion-responsive visual areas: the middle temporal area (MT) and the medial superior temporal area (MST). Using stimuli designed to tease apart differences in retinotopic organization and receptive field size, we established a double dissociation between two distinct MT � subregions in 8 of the 10 hemispheres studied. The first subregion exhibited retinotopic organization but did not respond to peripheral ipsilateral stimulation, indicative of smaller receptive fields. Conversely, the second subregion within MT � did not demonstrate retinotopic organization but did respond to peripheral stimuli in both the ipsilateral and contralateral visual hemifields, indicative of larger receptive fields. We tentatively identify these subregions as the
The functional anatomy of attention to visual motion - A functional MRI study
, 1998
"... this paper we have used functional MRI (fMRI) to identify the neural systems implicated in attending to visual motion ..."
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Cited by 65 (3 self)
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this paper we have used functional MRI (fMRI) to identify the neural systems implicated in attending to visual motion
Integration of visual and auditory information by superior temporal sulcus neurons responsive to the sight of actions
- J Cogn Neurosci
, 2005
"... & Processing of complex visual stimuli comprising facial movements, hand actions, and body movements is known to occur in the superior temporal sulcus (STS) of humans and nonhuman primates. The STS is also thought to play a role in the integration of multimodal sensory input. We investigated whe ..."
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Cited by 64 (5 self)
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& Processing of complex visual stimuli comprising facial movements, hand actions, and body movements is known to occur in the superior temporal sulcus (STS) of humans and nonhuman primates. The STS is also thought to play a role in the integration of multimodal sensory input. We investigated whether STS neurons coding the sight of actions also integrated the sound of those actions. For 23 % of neurons responsive to the sight of an action, the sound of that action significantly modulated the visual response. The sound of the action increased or decreased the visually evoked response for an equal number of neurons. In the neurons whose visual response was increased by the addition of sound (but not those neurons whose responses were decreased), the audiovisual integration was dependent upon the sound of the action matching the sight of the action. These results suggest that neurons in the STS form multisensory representations of observed actions. &
Organization of visual input to the inferior temporal and posterior parietal cortex in macaques
- Journal of Neuroscience
, 1991
"... It has been proposed that visual information in the extrastriate cortex is conveyed along 2 major processing pathways, a “dorsal ” pathway directed to the posterior parietal cortex, underlying spatial vision, and a “ventral ” pathway directed to the inferior temporal cortex, underlying object vision ..."
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Cited by 63 (0 self)
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It has been proposed that visual information in the extrastriate cortex is conveyed along 2 major processing pathways, a “dorsal ” pathway directed to the posterior parietal cortex, underlying spatial vision, and a “ventral ” pathway directed to the inferior temporal cortex, underlying object vision. To determine the relative distributions of cells projecting to the 2 pathways, we injected the posterior parietal and inferior temporal cortex with different fluorescent tracers in 5 rhesus monkeys. The parietal injections included the ventral intraparietal (VIP) and lateral intraparietal (LIP) areas, and the temporal injections included the lateral portions of cytoarchitectonic areas TE and TEO. There was a remarkable segregation of cells projecting to the 2 systems. Inputs to the parietal cortex tended to arise either from areas that have been implicated in spatial or motion analysis or from peripheral
The neural basis of the blood-oxygen-level-dependent functional magnetic resonance imaging signal
- Philos Trans R Soc Lond B Biol Sci
, 2002
"... Magnetic resonance imaging (MRI) has rapidly become an important tool in clinical medicine and biological research. Its functional variant (functional magnetic resonance imaging; fMRI) is currently the most widely used method for brain mapping and studying the neural basis of human cognition. While ..."
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Cited by 61 (2 self)
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Magnetic resonance imaging (MRI) has rapidly become an important tool in clinical medicine and biological research. Its functional variant (functional magnetic resonance imaging; fMRI) is currently the most widely used method for brain mapping and studying the neural basis of human cognition. While the method is widespread, there is insuf � cient knowledge of the physiological basis of the fMRI signal to interpret the data con � dently with respect to neural activity. This paper reviews the basic principles of MRI and fMRI, and subsequently discusses in some detail the relationship between the blood-oxygenlevel-dependent (BOLD) fMRI signal and the neural activity elicited during sensory stimulation. To examine this relationship, we conducted the � rst simultaneous intracortical recordings of neural signals and BOLD responses. Depending on the temporal characteristics of the stimulus, a moderate to strong correlation was found between the neural activity measured with microelectrodes and the BOLD signal averaged over a small area around the microelectrode tips. However, the BOLD signal had signi � cantly higher variability than the neural activity, indicating that human fMRI combined with traditional statistical methods underestimates the reliability of the neuronal activity. To understand the relative contribution of several types of neuronal signals to the haemodynamic response, we compared local � eld potentials (LFPs), single- and multi-unit activity (MUA) with high spatio-temporal fMRI responses recorded simultaneously in monkey visual cortex. At recording sites characterized by transient responses, only the LFP signal was signi � cantly correlated with the haemodynamic response. Furthermore, the LFPs had the largest magnitude signal and linear systems analysis showed that the LFPs were better than the MUAs at predicting the fMRI responses. These � ndings, together with an analysis of the neural signals, indicate that the BOLD signal primarily measures the input and processing of neuronal information within a region and not the output signal transmitted to other brain regions.
Neural dynamics of motion integration and segmentation within and across apertures
- Vision Research
, 2001
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Perceptually bistable threedimensional figures evoke high choice probabilities in cortical area MT
- J Neurosci
, 2001
"... The role of the primate middle temporal area (MT) in depth perception was examined by considering the trial-to-trial correlations between neuronal activity and reported depth sensations. A set of moving random dots portrayed a cylinder rotating about its principal axis. In this structure-from-motio ..."
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Cited by 48 (2 self)
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The role of the primate middle temporal area (MT) in depth perception was examined by considering the trial-to-trial correlations between neuronal activity and reported depth sensations. A set of moving random dots portrayed a cylinder rotating about its principal axis. In this structure-from-motion stimulus, the direction of rotation is ambiguous and the resulting percept undergoes spontaneous fluctuations. The stimulus can be rendered unambiguous by the addition of binocular disparities. We trained monkeys to report the direction of rotation in a set of these stimuli, one of which had zero disparity. Many disparityselective neurons in area MT are selective for the direction of rotation defined by disparity. Across repeated presentations of the ambiguous (zero-disparity) stimulus, there was a correlation between neuronal firing and the reported direction of rotation, as found by Key words: depth perception; kinetic depth effect; choice probability; cortical area MT; awake macaque; electrophysiology; stereopsis Cortical area MT (V5) in the macaque plays an important role in the perception of visual motion and recent evidence suggests a role in the perception of stereo depth. MT contains an ordered map of binocular disparity (DeAngelis and Newsome, 1999) and electrical microstimulation in MT influences the perceptual reports of monkeys in a stereo task Pursuing the link between activity and perception at the level of single neurons is more difficult. One approach is to measure simultaneous neuronal and perceptual responses to stimuli that support more than one interpretation. Trial-by-trial correlations between neuronal activity and perceptual reports provide critical evidence that neurons contribute to a visual percept More recently, a qualitatively similar correlation was demonstrated in a depth order task The stimulus can be rendered unambiguous by adding binocular disparities that define the depth order of the dots. Many MT neurons are selective for depth order in binocular stimuli The exact magnitude of the correlation between neuronal firing and perceptual reports is of critical importance for several reasons. First, it allows comparison with the data of
Superior temporal sulcus—It’s my area: or is it?
- Journal of Cognitive Neuroscience,
, 2008
"... Abstract & The superior temporal sulcus (STS) is the chameleon of the human brain. Several research areas claim the STS as the host brain region for their particular behavior of interest. Some see it as one of the core structures for theory of mind. For others, it is the main region for audiovi ..."
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Cited by 45 (0 self)
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Abstract & The superior temporal sulcus (STS) is the chameleon of the human brain. Several research areas claim the STS as the host brain region for their particular behavior of interest. Some see it as one of the core structures for theory of mind. For others, it is the main region for audiovisual integration. It plays an important role in biological motion perception, but is also claimed to be essential for speech processing and processing of faces. We review the foci of activations in the STS from multiple functional magnetic resonance imaging studies, focusing on theory of mind, audiovisual integration, motion processing, speech processing, and face processing. The results indicate a differentiation of the STS region in an anterior portion, mainly involved in speech processing, and a posterior portion recruited by cognitive demands of all these different research areas. The latter finding argues against a strict functional subdivision of the STS. In line with anatomical evidence from tracer studies, we propose that the function of the STS varies depending on the nature of network coactivations with different regions in the frontal cortex and medialtemporal lobe. This view is more in keeping with the notion that the same brain region can support different cognitive operations depending on task-dependent network connections, emphasizing the role of network connectivity analysis in neuroimaging. &
