scholarly journals Neuronal Distribution Across the Cerebral Cortex of the Marmoset Monkey (Callithrix jacchus)

2018 ◽  
Vol 29 (9) ◽  
pp. 3836-3863 ◽  
Author(s):  
Nafiseh Atapour ◽  
Piotr Majka ◽  
Ianina H Wolkowicz ◽  
Daria Malamanova ◽  
Katrina H Worthy ◽  
...  
Keyword(s):  
Cerebral Cortex ◽  
Visual Cortex ◽  
Complex Interaction ◽  
Anterior Cingulate ◽  
Functional Requirements ◽  
Anterior Cortex ◽  
Neuronal Density ◽  
Marmoset Monkey ◽  
Posterior Parietal ◽  
Neuronal Distribution

Abstract Using stereological analysis of NeuN-stained sections, we investigated neuronal density and number of neurons per column throughout the marmoset cortex. Estimates of mean neuronal density encompassed a greater than 3-fold range, from >150 000 neurons/mm3 in the primary visual cortex to ~50 000 neurons/mm3 in the piriform complex. There was a trend for density to decrease from posterior to anterior cortex, but also local gradients, which resulted in a complex pattern; for example, in frontal, auditory, and somatosensory cortex neuronal density tended to increase towards anterior areas. Anterior cingulate, motor, premotor, insular, and ventral temporal areas were characterized by relatively low neuronal densities. Analysis across the depth of the cortex revealed greater laminar variation of neuronal density in occipital, parietal, and inferior temporal areas, in comparison with other regions. Moreover, differences between areas were more pronounced in the supragranular layers than in infragranular layers. Calculations of the number of neurons per unit column revealed a pattern that was distinct from that of neuronal density, including local peaks in the posterior parietal, superior temporal, precuneate, frontopolar, and temporopolar regions. These results suggest that neuronal distribution in adult cortex result from a complex interaction of developmental/ evolutionary determinants and functional requirements.

scholarly journals Neuronal distribution across the cerebral cortex of the marmoset monkey (Callithrix jacchus)

2018 ◽  
Author(s):  
Nafiseh Atapour ◽  
Piotr Majka ◽  
Ianina H. Wolkowicz ◽  
Daria Malamanova ◽  
Katrina H. Worthy ◽  
...  
Keyword(s):  
Cerebral Cortex ◽  
Visual Cortex ◽  
Complex Interaction ◽  
Anterior Cingulate ◽  
Functional Requirements ◽  
Anterior Cortex ◽  
Neuronal Density ◽  
Marmoset Monkey ◽  
Posterior Parietal ◽  
Neuronal Distribution

AbstractUsing stereological analysis of NeuN-stained sections, we investigated neuronal density and number of neurons per column throughout the marmoset cortex. Estimates of mean neuronal density encompassed a greater than threefold range, from >150,000 neurons/ mm3 in the primary visual cortex to ~50,000 neurons/ mm3 in the piriform complex. There was a trend for density to decrease from posterior to anterior cortex, but also local gradients, which resulted in a complex pattern; for example, in frontal, auditory and somatosensory cortex neuronal density tended to increase towards anterior areas. Anterior cingulate, motor, premotor, insular and ventral temporal areas were characterized by relatively low neuronal densities. Analysis across the depth of the cortex revealed greater laminar variation of neuronal density in occipital, parietal and inferior temporal areas, in comparison with other regions. Moreover, differences between areas were more pronounced in the supragranular layers than in infragranular layers. Calculations of the number of neurons per unit column revealed a pattern that was distinct from that of neuronal density, including local peaks in the posterior parietal, superior temporal, precuneate, frontopolar and temporopolar regions. These results suggest that neuronal distribution in adult cortex result from a complex interaction of developmental/ evolutionary determinants and functional requirements.

scholarly journals Attentional bias to threat and gray mater volume morphology in high anxious individuals

2020 ◽  
Author(s):  
Joshua M. Carlson ◽  
Lin Fang
Keyword(s):  
Attentional Bias ◽  
Parietal Cortex ◽  
Gray Matter ◽  
Posterior Parietal Cortex ◽  
Gray Matter Volume ◽  
Anterior Cingulate ◽  
Brain Morphology ◽  
Matter Volume ◽  
Posterior Parietal ◽  
The Right

AbstractIn a sample of highly anxious individuals, the relationship between gray matter volume brain morphology and attentional bias to threat was assessed. Participants performed a dot-probe task of attentional bias to threat and gray matter volume was acquired from whole brain structural T1-weighted MRI scans. The results replicate previous findings in unselected samples that elevated attentional bias to threat is linked to greater gray matter volume in the anterior cingulate cortex, middle frontal gyrus, and striatum. In addition, we provide novel evidence that elevated attentional bias to threat is associated with greater gray matter volume in the right posterior parietal cortex, cerebellum, and other distributed regions. Lastly, exploratory analyses provide initial evidence that distinct sub-regions of the right posterior parietal cortex may contribute to attentional bias in a sex-specific manner. Our results illuminate how differences in gray matter volume morphology relate to attentional bias to threat in anxious individuals. This knowledge could inform neurocognitive models of anxiety-related attentional bias to threat and targets of neuroplasticity in anxiety interventions such as attention bias modification.

scholarly journals Perceptual detection depends on spike count integration

2019 ◽  
Author(s):  
Jackson J. Cone ◽  
Morgan L. Bade ◽  
Nicolas Y. Masse ◽  
Elizabeth A. Page ◽  
David J. Freedman ◽  
...  
Keyword(s):  
Neural Networks ◽  
Cerebral Cortex ◽  
Visual Cortex ◽  
Recurrent Neural Networks ◽  
Neural Circuit ◽  
Visual Detection ◽  
Spike Count ◽  
Neuronal Responses ◽  
Neuronal Populations ◽  
And Behavior

AbstractWhenever the retinal image changes some neurons in visual cortex increase their rate of firing, while others decrease their rate of firing. Linking specific sets of neuronal responses with perception and behavior is essential for understanding mechanisms of neural circuit computation. We trained mice to perform visual detection tasks and used optogenetic perturbations to increase or decrease neuronal spiking primary visual cortex (V1). Perceptual reports were always enhanced by increments in V1 spike counts and impaired by decrements, even when increments and decrements were delivered to the same neuronal populations. Moreover, detecting changes in cortical activity depended on spike count integration rather than instantaneous changes in spiking. Recurrent neural networks trained in the task similarly relied on increments in neuronal activity when activity was costly. This work clarifies neuronal decoding strategies employed by cerebral cortex to translate cortical spiking into percepts that can be used to guide behavior.

scholarly journals Feedback from human posterior parietal cortex enables visuospatial category representations as early as primary visual cortex

2017 ◽  
Vol 8 (1) ◽  
pp. e00886
Author(s):  
Yanyan Li ◽  
Xiaopeng Hu ◽  
Yongqiang Yu ◽  
Ke Zhao ◽  
Yuri B. Saalmann ◽  
...  
Keyword(s):  
Visual Cortex ◽  
Primary Visual Cortex ◽  
Parietal Cortex ◽  
Posterior Parietal Cortex ◽  
Posterior Parietal

Cortex: Topography and Organization

2021 ◽  
pp. 175-178
Author(s):  
Richard J. Caselli ◽  
David T. Jones
Keyword(s):  
Cerebral Cortex ◽  
Visual Cortex ◽  
Gray Matter ◽  
Striate Cortex ◽  
Neuronal Cell ◽  
Area 17 ◽  
Neuronal Cell Bodies ◽  
Brodmann Areas ◽  
Functional Components ◽  
Complex Activities

The cerebral cortex is involved in various simple and complex activities. It consists of layers of neuronal cell bodies (ie, gray matter) that are organized into gyri (convolutions).The cortex can be divided into functional components in several ways. Various schemes are based on function, cytoarchitecture, topography, or Brodmann areas. The terminology can be confusing because the same area of cortex could be designated by several names. For instance, Brodmann area 17 is also called the primary visual cortex, the striate cortex, and the calcarine cortex. Brodmann designated 52 regions of the cerebral cortex according to cytoarchitecture.

scholarly journals The Effect of Attention on Neuronal Responses to High and Low Contrast Stimuli

2010 ◽  
Vol 104 (2) ◽  
pp. 960-971 ◽  
Author(s):  
Joonyeol Lee ◽  
John H. R. Maunsell
Keyword(s):  
Cerebral Cortex ◽  
Visual Cortex ◽  
Rhesus Monkeys ◽  
Receptive Fields ◽  
Visual Area ◽  
Neuronal Responses ◽  
Attentional Modulation ◽  
Low Contrast ◽  
Middle Temporal ◽  
Visual Area Mt

It remains unclear how attention affects the tuning of individual neurons in visual cerebral cortex. Some observations suggest that attention preferentially enhances responses to low contrast stimuli, whereas others suggest that attention proportionally affects responses to all stimuli. Resolving how attention affects responses to different stimuli is essential for understanding the mechanism by which it acts. To explore the effects of attention on stimuli of different contrasts, we recorded from individual neurons in the middle temporal visual area (MT) of rhesus monkeys while shifting their attention between preferred and nonpreferred stimuli within their receptive fields. This configuration results in robust attentional modulation that makes it possible to readily distinguish whether attention acts preferentially on low contrast stimuli. We found no evidence for greater enhancement of low contrast stimuli. Instead, the strong attentional modulations were well explained by a model in which attention proportionally enhances responses to stimuli of all contrasts. These data, together with observations on the effects of attention on responses to other stimulus dimensions, suggest that the primary effect of attention in visual cortex may be to simply increase the strength of responses to all stimuli by the same proportion.

Experience-Dependent Neural Integration of Taste and Smell in the Human Brain

2004 ◽  
Vol 92 (3) ◽  
pp. 1892-1903 ◽  
Author(s):  
Dana M. Small ◽  
Joel Voss ◽  
Y. Erica Mak ◽  
Katharine B. Simmons ◽  
Todd Parrish ◽  
...  
Keyword(s):  
Prefrontal Cortex ◽  
Parietal Cortex ◽  
Posterior Parietal Cortex ◽  
Anterior Cingulate ◽  
Brain Response ◽  
Liquid Form ◽  
Flavor Perception ◽  
Odor Pair ◽  
Frontal Operculum ◽  
Posterior Parietal

Flavor perception arises from the central integration of peripherally distinct sensory inputs (taste, smell, texture, temperature, sight, and even sound of foods). The results from psychophysical and neuroimaging studies in humans are converging with electrophysiological findings in animals and a picture of the neural correlates of flavor processing is beginning to emerge. Here we used event-related fMRI to evaluate brain response during perception of flavors (i.e., taste/odor liquid mixtures not differing in temperature or texture) compared with the sum of the independent presentation of their constituents (taste and/or odor). All stimuli were presented in liquid form so that olfactory stimulation was by the retronasal route. Mode of olfactory delivery is important because neural suppression has been observed in chemosensory regions during congruent taste–odor pairs when the odors are delivered by the orthonasal route and require subjects to sniff. There were 2 flavors. One contained a familiar/congruent taste–odor pair (vanilla/sweet) and the other an unfamiliar/incongruent taste–odor pair (vanilla/salty). Three unimodal stimuli, including 2 tastes (sweet and salty) and one odor (vanilla), as well as a tasteless/odorless liquid (baseline) were presented. Superadditive responses during the perception of the congruent flavor compared with the sum of its constituents were observed in the anterior cingulate cortex (ACC), dorsal insula, anterior ventral insula extending into the caudal orbitofrontal cortex (OFC), frontal operculum, ventral lateral prefrontal cortex, and posterior parietal cortex. These regions were not present in a similar analysis of the incongruent flavor compared with the sum of its constituents. All of these regions except the ventrolateral prefrontal cortex were also isolated in a direct contrast of congruent − incongruent. Additionally, the anterior cingulate, posterior parietal cortex, frontal operculum, and ventral insula/caudal OFC were also more active in vanilla + salty minus incongruent, suggesting that delivery of an unfamiliar taste–odor combination may lead to suppressed neural responses. Taken together with previous findings in the literature, these results suggest that the insula, OFC, and ACC are key components of the network underlying flavor perception and that taste–smell integration within these and other regions is dependent on 1) mode of olfactory delivery and 2) previous experience with taste/smell combinations.

A collicular visual cortex: Neocortical space for an ancient midbrain visual structure

Science ◽  
2019 ◽  
Vol 363 (6422) ◽  
pp. 64-69 ◽  
Author(s):  
Riccardo Beltramo ◽  
Massimo Scanziani
Keyword(s):  
Cerebral Cortex ◽  
Visual Cortex ◽  
Primary Visual Cortex ◽  
Visual Information ◽  
Cortical Area ◽  
Moving Objects ◽  
Visual Responses ◽  
Visual Cortical Area ◽  
Postrhinal Cortex ◽  
Visual Cortical

Visual responses in the cerebral cortex are believed to rely on the geniculate input to the primary visual cortex (V1). Indeed, V1 lesions substantially reduce visual responses throughout the cortex. Visual information enters the cortex also through the superior colliculus (SC), but the function of this input on visual responses in the cortex is less clear. SC lesions affect cortical visual responses less than V1 lesions, and no visual cortical area appears to entirely rely on SC inputs. We show that visual responses in a mouse lateral visual cortical area called the postrhinal cortex are independent of V1 and are abolished upon silencing of the SC. This area outperforms V1 in discriminating moving objects. We thus identify a collicular primary visual cortex that is independent of the geniculo-cortical pathway and is capable of motion discrimination.

Hierarchical Equivalence of Somatosensory Areas I and II for Tactile Processing in the Cerebral Cortex of the Marmoset Monkey

2001 ◽  
Vol 85 (5) ◽  
pp. 1823-1835 ◽  
Author(s):  
H. Q. Zhang ◽  
M. K. Zachariah ◽  
G. T. Coleman ◽  
M. J. Rowe
Keyword(s):  
Cerebral Cortex ◽  
Evoked Potentials ◽  
Phase Locking ◽  
Simultaneous Recording ◽  
Vibrotactile Stimulation ◽  
Reversible Inactivation ◽  
Somatosensory Area ◽  
Marmoset Monkey ◽  
Tactile Stimuli ◽  
Functional Classes

Responsiveness of the first somatosensory area (SI) of the cerebral cortex was investigated in the marmoset monkey ( Callithrix jacchus) in association with cooling-induced, reversible inactivation of the second somatosensory area, SII. The aim was to determine whether SI responsiveness to peripheral tactile stimulation depends on SII and therefore whether SI and SII in the marmoset occupy hierarchically equivalent positions in a parallel organizational scheme for thalamocortical tactile processing as appears to be the case in nonprimate mammals. Inactivation of SII was achieved when the temperature over SII was lowered to ≤12°C, as indicated by abolition of the SII-evoked potentials generated by brief tap stimuli to the hand or foot, and by abolition of tactile responses in single SII neurons located at the margin beneath the block. The effect of SII inactivation on SI-evoked potentials was examined in 16 experiments by simultaneous recording of the SI- and SII-evoked potentials. SI-evoked potentials were never abolished and remained unaffected in 11 cases. In three experiments there was a small reduction in amplitude and inconsistent effects in the remaining two. Responsiveness to controlled tactile stimuli was examined quantitatively in 31 individual SI neurons of different functional classes before, during, and after the inactivation of SII. Tactile responsiveness in individual SI neurons was never abolished by SII inactivation, remaining unchanged in 20 neurons (65%) while undergoing some reduction in the remaining 11 SI neurons (35%). This reduction of tactile responsiveness in one-third of SI neurons is most likely attributable to a removal of a facilitatory influence emanating from SII, based on the observation that background activity of the affected neurons was also reduced. Furthermore, phase locking of SI responses to vibrotactile stimulation was unchanged when SII was inactivated. The retention of responsiveness in SI neurons when SII was inactivated by cooling in the marmoset demonstrates that tactile inputs can reach SI without traversing an indirect, serially organized path through SII. The present results, together with our previous observations that responsiveness in the majority of SII neurons survived SI inactivation, demonstrate that there is a parallel organization of the SI and SII areas for tactile processing in the marmoset monkey and that SI and SII occupy hierarchically equivalent positions in a parallel processing network. There is therefore no longer justification for the view that there are fundamental differences in the organization of thalamocortical tactile processing for SI and SII between simian primates, in general, and other mammals.

Changing patterns of synaptic input to subplate and cortical plate during development of visual cortex

1991 ◽  
Vol 66 (6) ◽  
pp. 2059-2071 ◽  
Author(s):  
E. Friauf ◽  
C. J. Shatz
Keyword(s):  
Cerebral Cortex ◽  
Visual Cortex ◽  
Synaptic Input ◽  
Field Potential ◽  
Short Latency ◽  
Cortical Plate ◽  
Synaptic Activation ◽  
Cortical Layers ◽  
Subplate Neurons ◽  
Monosynaptic Excitation

1. The development of excitatory activation in the visual cortex was studied in fetal and neonatal cats. During fetal and neonatal life, the immature cerebral cortex (the cortical plate) is sandwiched between two synaptic zones: the marginal zone above, and an area just below the cortical plate, the subplate. The subplate is transient and disappears by approximately 2 mo postnatal. Here we have investigated whether the subplate and the cortical plate receive functional synaptic inputs in the fetus, and when the adultlike pattern of excitatory synaptic input to the cortical plate appears during development. 2. Extracellular field potential recording to electrical stimulation of the optic radiation was performed in slices of cerebral cortex maintained in vitro. Laminar profiles of field potentials were converted by the current-source density (CSD) method to identify the spatial and temporal distribution of neuronal excitation within the subplate and the cortical plate. 3. Between embryonic day 47 (E47) and postnatal day 28 (P28; birth, E65), age-related changes occur in the pattern of synaptic activation of neurons in the cortical plate and the subplate. Early in development, at E47, E57, and P0, short-latency (probably monosynaptic) excitation is most obvious in the subplate, and longer latency (presumably polysynaptic) excitation can be seen in the cortical plate. Synaptic excitation in the subplate is no longer apparent at P21 and P28, a time when cell migration is finally complete and the cortical layers have formed. By contrast, excitation in the cortical plate is prominent in postnatal animals, and the temporal and spatial pattern has changed. 4. The adultlike sequence of synaptic activation in the different cortical layers can be seen by P28. It differs from earlier ages in several respects. First, short-latency (probably monosynaptic) excitation can be detected in cortical layer 4. Second, multisynaptic, long-lasting activation is present in layers 2/3 and 5. 5. Our results show that the subplate zone, known from anatomic studies to be a synaptic neurophil during development, receives functional excitatory inputs from axons that course in the developing white matter. Because the only mature neurons present in this zone are the subplate neurons, we conclude that subplate neurons are the principal, if not the exclusive, recipients of this input. The results suggest further that the excitation in the subplate in turn is relayed to neurons of the cortical plate via axon collaterals of subplate neurons.(ABSTRACT TRUNCATED AT 400 WORDS)

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