Highly ordered arrangement of single neurons in orientation pinwheels

Ohki, Kenichi; Chung, Shin-Ho; Kara, Prakash; Hübener, Mark; Bonhoeffer, Tobias; Reid, R. Clay

doi:10.1038/nature05019

Cited by 306 publications

(295 citation statements)

References 30 publications

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“…2D; P Ͼ 0.1; Wilcoxon signedrank test). This result further supports the idea that response heterogeneity is not inconsistent with the precision of functional architecture (7,8).…”

Section: Materials and Methods)supporting

confidence: 78%

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Efficient coding in heterogeneous neuronal populations

Chelaru

Dragoi

2008

Proc. Natl. Acad. Sci. U.S.A.

141

148

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A ubiquitous feature of neuronal responses within a cortical area is their high degree of inhomogeneity. Even cells within the same functional column are known to have highly heterogeneous response properties when the same stimulus is presented. Whether the wide diversity of neuronal responses is an epiphenomenon or plays a role for cortical function is unknown. Here, we examined the relationship between the heterogeneity of neuronal responses and population coding. Contrary to our expectation, we found that the high variability of intrinsic response properties of individual cells changes the structure of neuronal correlations to improve the information encoded in the population activity. Thus, the heterogeneity of neuronal responses is in fact beneficial for sensory coding when stimuli are decoded from the population response.computational modeling ͉ information coding ͉ sensory cortex ͉ visual cortex ͉ neuronal populations

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“…2D; P Ͼ 0.1; Wilcoxon signedrank test). This result further supports the idea that response heterogeneity is not inconsistent with the precision of functional architecture (7,8).…”

Section: Materials and Methods)supporting

confidence: 78%

“…Thus, two-photon calcium imaging studies have recently demonstrated that the functional architecture of orientation and direction selectivity in cat visual cortex (7,8) is extraordinarily precise. For instance, in area 18, neurons preferring opposite stimulus directions were segregated by remarkably specific ''fractures'' that were one to two cells wide (7).…”

mentioning

confidence: 99%

Efficient coding in heterogeneous neuronal populations

Chelaru

Dragoi

2008

Proc. Natl. Acad. Sci. U.S.A.

141

148

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“…The situation is less clear, however, for other stimulus parameters, such as orientation. Gradual variation of stimulus orientation produces a gradual shift of orientation preference in numerous v1 subregions 60 , but these regions are separated by singularities (pinwheel centres) in which the orientation preference shifts abruptly [61][62][63] . This pattern is sometimes referred to as a mosaic-like map 64 .…”

Section: Maps and Modules In Primary Sensory Cortexmentioning

confidence: 99%

Interpreting fMRI data: maps, modules and dimensions

2008

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Neuroimaging research over the past decade has revealed a detailed picture of the functional organization of the human brain. Here we focus on two fundamental questions that are raised by the detailed mapping of sensory and cognitive functions and illustrate these questions with findings from the object-vision pathway. First, are functionally specific regions that are located close together best understood as distinct cortical modules or as parts of a larger-scale cortical map? Second, what functional properties define each cortical map or module? We propose a model in which overlapping continuous maps of simple features give rise to discrete modules that are selective for complex stimuli.Advances in brain imaging technology (especially functional MRI (fMRI)) have radically improved our understanding of the functional organization of the human brain (BOX 1). In this Review we describe the organization of the ventral visual pathway, which is characterized by strong selectivity for particular object categories (for example, faces and bodies) at the level of both individual neurons and larger cortical regions. We then consider two central questions: whether this organization reflects maps or modules, and what properties are mapped. In each case we derive clues from the literature on the primary sensory cortex, in which cortical maps have been studied extensively using electrophysiology in animals. We find that apparently modular cortical regions, such as orientation columns and face-selective regions, might be parts of larger maps, and show that it is a substantial challenge to determine the basic properties and dimensions that describe functional organization most parsimoniously. We then propose a new framework that reconciles the existence of graded cortical maps and distinct functional modules. In this framework, the strong category selectivity that exists for faces and other objects might arise from the nonlinear combination of multiple correlated maps for simpler stimulus properties. The ventral visual pathwayThe ventral visual pathway comprises a large cortical region that occupies the ventral and lateral surfaces of the occipital and temporal lobes (FIG. 1). A substantial proportion of fMRI voxels in this pathway are 'object-selective' -that is, they respond more strongly when people view images of objects than when people view scrambled versions of these objects or texture patterns. This object-selective region is often referred to as the lateral occipital complex (LOC) 1 . The LOC has little selectivity for particular stimulus categories 2-4 , but several regions of NIH-PA Author ManuscriptNIH-PA Author Manuscript NIH-PA Author Manuscript cortex near the LOC are selective for particular object categories: they respond at least twice as strongly to their 'preferred' stimuli than to other stimuli. For example, in essentially all humans cortical regions can be found that respond selectively to faces (the fusiform face area (FFA) 5,6 and, in many individuals, the occipital face area (OFA)) 7,8 , to pl...

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“…Here, we use regional imaging of intrinsic optical signals (IOSs) to define macroscopic remapping in somatosensory cortex of mice with targeted ischemic insults (Zhang et al, 2005;Schaffer et al, 2006;Brown et al, 2007;Zhang and Murphy, 2007). We then perform in vivo two-photon calcium imaging at different sites within these regional maps, as previously used in the visual and somatosensory cortex of unlesioned animals (Stosiek et al, 2003;Ohki et al, 2005Ohki et al, , 2006Kerr et al, 2007;Mrsic-Flogel et al, 2007;Sato et al, 2007;Winship et al, 2007). By optically recording neuronal activity using in vivo Ca 2ϩ imaging, we assessed stroke-induced changes in sensory-evoked function and spatial organization of Ͼ10,000 individual, visually identified cells in cortical layers 2/3.…”

Section: Introductionmentioning

confidence: 99%

In Vivo Calcium Imaging Reveals Functional Rewiring of Single Somatosensory Neurons after Stroke

Winship¹,

Murphy²

2008

Journal of Neuroscience

161

182

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Functional mapping and microstimulation studies suggest that recovery after stroke damage can be attributed to surviving brain regions taking on the functional roles of lost tissues. Although this model is well supported by data, it is not clear how activity in single neurons is altered in relation to cortical functional maps. It is conceivable that individual surviving neurons could adopt new roles at the expense of their usual function. Alternatively, neurons that contribute to recovery may take on multiple functions and exhibit a wider repertoire of neuronal processing. In vivo two-photon calcium imaging was used in adult mice within reorganized forelimb and hindlimb somatosensory functional maps to determine how the response properties of individual neurons and glia were altered during recovery from ischemic damage over a period of 2-8 weeks. Single-cell calcium imaging revealed that the limb selectivity of individual neurons was altered during recovery from ischemia, such that neurons normally selective for a single contralateral limb processed information from multiple limbs. Altered limb selectivity was most prominent in border regions between stroke-altered forelimb and hindlimb macroscopic map representations, and peaked 1 month after the targeted insult. Two months after stroke, individual neurons near the center of reorganized functional areas became more selective for a preferred limb. These previously unreported forms of plasticity indicate that in adult animals, seemingly hardwired cortical neurons first adopt wider functional roles as they develop strategies to compensate for loss of specific sensory modalities after forms of brain damage such as stroke.

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Highly ordered arrangement of single neurons in orientation pinwheels

Cited by 306 publications

References 30 publications

Efficient coding in heterogeneous neuronal populations

Efficient coding in heterogeneous neuronal populations

Interpreting fMRI data: maps, modules and dimensions

In Vivo Calcium Imaging Reveals Functional Rewiring of Single Somatosensory Neurons after Stroke

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