scholarly journals Diversity of Feature Selectivity in Macaque Visual Cortex Arising from a Limited Number of Broadly Tuned Input Channels

2019 ◽  
Vol 29 (12) ◽  
pp. 5255-5268
Author(s):  
Yamni S Mohan ◽  
Jaikishan Jayakumar ◽  
Errol K J Lloyd ◽  
Ekaterina Levichkina ◽  
Trichur R Vidyasagar
Keyword(s):  
Visual Cortex ◽  
Full Range ◽  
Cortical Cells ◽  
Intrinsic Signals ◽  
Thalamic Input ◽  
Feature Selectivity ◽  
The One ◽  
Visual Cortical ◽  
Orientation Domain ◽  
Preferred Stimulus

AbstractSpike (action potential) responses of most primary visual cortical cells in the macaque are sharply tuned for the orientation of a line or an edge, and neurons preferring similar orientations are clustered together in cortical columns. The preferred stimulus orientation of these columns span the full range of orientations, as observed in recordings of spikes and in classical optical imaging of intrinsic signals. However, when we imaged the putative thalamic input to striate cortical cells that can be seen in imaging of intrinsic signals when they are analyzed on a larger spatial scale, we found that the orientation domain map of the primary visual cortex did not show the same diversity of orientations. This map was dominated by just the one orientation that is most commonly preferred by neurons in the retina and the lateral geniculate nucleus. This supports cortical feature selectivity and columnar architecture being built upon feed-forward signals transmitted from the thalamus in a very limited number of broadly tuned input channels.

scholarly journals Diversity of feature selectivity in macaque visual cortex arising from limited number of broadly-tuned input channels

2018 ◽  
Author(s):  
Yamni S. Mohan ◽  
Jaikishan Jayakumar ◽  
Errol K.J. Lloyd ◽  
Ekaterina Levichkina ◽  
Trichur R. Vidyasagar
Keyword(s):  
Visual Cortex ◽  
Cortical Neurons ◽  
Full Range ◽  
Cortical Cells ◽  
Thalamic Input ◽  
Feature Selectivity ◽  
The One ◽  
Visual Cortical ◽  
Orientation Domain ◽  
Preferred Stimulus

AbstractSpikes (action potential) responses of most primary visual cortical cells in the macaque are sharply tuned for the orientation of a line or an edge and neurons preferring similar orientations are clustered together in cortical columns. The preferred stimulus orientation of these columns span the full range of orientations, as observed in recordings of spikes, which represent the outputs of cortical neurons. However, when we imaged also the thalamic input to these cells that occur on a larger spatial scale, we found that the orientation domain map of the primary visual cortex did not show the diversity of orientations exhibited by signals representing outputs of the cells. This map was dominated by just the one orientation that is most commonly represented in subcortical responses. This supports cortical feature selectivity and columnar architecture being built upon feed-forward signals transmitted from the thalamus in a very limited number of broadly-tuned input channels.

Postnatal development of functional properties of visual cortical cells in rats with excitotoxic lesions of basal forebrain cholinergic neurons

1997 ◽  
Vol 14 (1) ◽  
pp. 111-123 ◽  
Author(s):  
Rosita Siciliano ◽  
Gigliola Fontanesi ◽  
Fiorella Casamenti ◽  
Nicoletta Berardi ◽  
Paola Bagnoli ◽  
...  
Keyword(s):  
Visual Cortex ◽  
Postnatal Development ◽  
Functional Properties ◽  
Basal Forebrain ◽  
Critical Period ◽  
Ocular Dominance ◽  
Cholinergic Neurons ◽  
Field Size ◽  
Cortical Cells ◽  
Visual Cortical

AbstractIn the rat, visual cortical cells develop their functional properties during a period termed as critical period, which is included between eye opening, i.e.˘postnatal day (PD) 15, and PD40. The present investigation was aimed at studying the influence of cortical cholinergic afferents from the basal forebrain (BF) on the development of functional properties of visual cortical neurons. At PD15, rats were unilaterally deprived of the cholinergic input to the visual cortex by stereotaxic injections of quisqualic acid in BF cholinergic nuclei projecting to the visual cortex. Cortical cell functional properties, such as ocular dominance, orientation selectivity, receptive-field size, and cell responsiveness were then assessed by extracellular recordings in the visual cortex ipsilateral to the lesioned BF both during the critical period (PD30) and after its end (PD45). After the recording session, the rats were sacrificed and the extent of both cholinergic lesion in BF and cholinergic depletion in the visual cortex was determined. Our results show that lesion of BF cholinergic nuclei transiently alters the ocular dominance of visual cortical cells while it does not affect the other functional properties tested. In particular, in lesioned animals recorded during the critical period, a higher percentage of visual cortical cells was driven by the contralateral eye with respect to normal animals. After the end of the critical period, the ocular dominance distribution of animals with cholinergic deafferentation was not significantly different from that of controls. Our results suggest the possibility that lesions of BF cholinergic neurons performed during postnatal development only transiently interfere with cortical competitive processes.

scholarly journals Reorganization of Visual Cortical Maps after Focal Ischemic Lesions

2003 ◽  
Vol 23 (7) ◽  
pp. 811-820 ◽  
Author(s):  
Angelica Zepeda ◽  
Luis Vaca ◽  
Clorinda Arias ◽  
Frank Sengpiel
Keyword(s):  
Visual Cortex ◽  
Visual Space ◽  
Ischemic Lesion ◽  
Orientation Preference ◽  
Intrinsic Signals ◽  
Time Points ◽  
Imaging Results ◽  
Visual Cortical ◽  
Cortical Representations ◽  
Over Time

Plasticity after central lesions may result in the reorganization of cortical representations of the sensory input. Visual cortex reorganization has been extensively studied after peripheral (retinal) lesions, but focal cortical lesions have received less attention. In this study, we investigated the organization of retinotopic and orientation preference maps at different time points after a focal ischemic lesion in the primary visual cortex (V1). We induced a focal photochemical lesion in V1 of kittens and assessed, through optical imaging of intrinsic signals, the functional cortical layout immediately afterwards and at 4, 13, 33, and 40 days after lesion. We analyzed histologic sections and evaluated temporal changes of functional maps. Histological analysis showed a clear lesion at all time points, which shrank over time. Imaging results showed that the retinotopic and orientation preference maps reorganize to some extent after the lesion. Near the lesion, the cortical retinotopic representation of one degree of visual space expands over time, while at the same time the area of some orientation domains also increases. These results show that different cortical representations can reorganize after a lesion process and suggest a mechanism through which filling-in of a cortical scotoma can occur in cortically damaged patients.

Modulatory effects of catecholamines on neurons of the rat visual cortex: single-cell iontophoretic studies

1989 ◽  
Vol 67 (6) ◽  
pp. 615-623 ◽  
Author(s):  
Arlette Kolta ◽  
Tomás A. Reader
Keyword(s):  
Visual Cortex ◽  
Adrenergic Receptors ◽  
Signal To Noise Ratio ◽  
Single Cells ◽  
Firing Frequency ◽  
Adrenergic Agonist ◽  
Cortical Cells ◽  
Hyperpolarizing Response ◽  
Main Component ◽  
Visual Cortical

The catecholamines noradrenaline and dopamine have been proposed as neuromodulators of cortical neuron excitability, and such a regulation could be mediated by specific adrenergic and dopaminergic receptors. We characterized electrophysiologically some of the types of responses to the iontophoretic application of adrenergic and dopaminergic agonists and antagonists on single cells in the rat visual cortex (areas occipital 1 monocular or Oc 1 M and occipital 1 binocular or Oc 1 B). For the majority of spontaneously active and visual cortical cells, noradrenaline and dopamine decreased the firing frequency. In the case of visually driven (synaptically activated) neurons, background firing was the main component of the response to be inhibited by the administration of noradrenaline, clonidine, and oxymetazoline, leading to an enhancement of the signal-to-noise ratio. Since these effects could be reduced or blocked by a previous ejection of the specific α2-antagonist idazoxan, the findings support a role for α2-adrenergic receptors in the transmission of sensory inputs to the visual cortex. These effects were not found with the mixed α-adrenergic agonist phenylephrine nor with the β-agonist isoproterenol. Finally, the use of the inhibitory amino acid GABA rules out a simple hyperpolarizing response as the mechanism underlying noradrenaline modulatory effects in the cerebral cortex.Key words: visual cortex, noradrenaline, dopamine, iontophoresis, neuromodulators.

scholarly journals Inhibition of Cdk5 in PV Neurons Reactivates Experience-Dependent Plasticity in Adult Visual Cortex

2021 ◽  
Vol 23 (1) ◽  
pp. 186
Author(s):  
Xinxin Zhang ◽  
Huiping Tang ◽  
Sitong Li ◽  
Yueqin Liu ◽  
Wei Wu ◽  
...  
Keyword(s):  
Visual Cortex ◽  
Cortical Plasticity ◽  
Ocular Dominance ◽  
Critical Role ◽  
Threshold Current ◽  
Inhibitory Neurons ◽  
Resting Membrane Potential ◽  
Intrinsic Signals ◽  
Single Action ◽  
Visual Cortical

Cyclin-dependent kinase 5 (Cdk5) has been shown to play a critical role in brain development, learning, memory and neural processing in general. Cdk5 is widely distributed in many neuron types in the central nervous system, while its cell-specific role is largely unknown. Our previous study showed that Cdk5 inhibition restored ocular dominance (OD) plasticity in adulthood. In this study, we specifically knocked down Cdk5 in different types of neurons in the visual cortex and examined OD plasticity by optical imaging of intrinsic signals. Downregulation of Cdk5 in parvalbumin-expressing (PV) inhibitory neurons, but not other neurons, reactivated adult mouse visual cortical plasticity. Cdk5 knockdown in PV neurons reduced the evoked firing rate, which was accompanied by an increment in the threshold current for the generation of a single action potential (AP) and hyperpolarization of the resting membrane potential. Moreover, chemogenetic activation of PV neurons in the visual cortex can attenuate the restoration of OD plasticity by Cdk5 inhibition. Taken together, our results suggest that Cdk5 in PV interneurons may play a role in modulating the excitation and inhibition balance to control the plasticity of the visual cortex.

Role of visual experience in activating critical period in cat visual cortex

1985 ◽  
Vol 53 (2) ◽  
pp. 572-589 ◽  
Author(s):  
G. D. Mower ◽  
W. G. Christen
Keyword(s):  
Visual Cortex ◽  
Visual Experience ◽  
Ocular Dominance ◽  
Orientation Selectivity ◽  
Monocular Deprivation ◽  
Total Darkness ◽  
Cortical Cells ◽  
Visual Cortical ◽  
Dark Rearing ◽  
Made In

Cats were reared in total darkness from birth until 4-5 mo of age (DR cats, n = 7) or with very brief visual experience (1 or 2 days) during an otherwise similar period of dark rearing [DR(1) cats, n = 3; DR(2) cats, n = 7]. Single-cell recordings were made in area 17 of visual cortex at the end of this rearing period and/or after a subsequent prolonged period of monocular deprivation. Control observations were made in normal cats (n = 3), cats reared with monocular deprivation from birth (n = 4), and cats monocularly deprived after being reared normally until 4 mo of age (n = 2). After rearing cats in total darkness, the majority of visual cortical cells were binocularly driven and the overall distribution of ocular dominance was not different from that of normal cats. Orientation-selective cells were very rare in dark-reared cats. Monocular deprivation imposed after dark rearing resulted in selective development of connections from the open eye. Most cells were responsive only to the open eye and the majority of these were orientation selective. These results were similar to, though less severe than, those found in cats reared with monocular deprivation from birth. Monocular deprivation imposed after 4 mo of normal rearing did not produce selective development of connections from the open eye in terms of either ocular dominance or orientation selectivity. In DR(1) cats visual cortical physiology was degraded in comparison to dark-reared cats after the rearing period. Most cells were binocularly driven but there was a higher frequency of unresponsive cells and a reduced frequency of orientation-selective cells. Subsequent monocular deprivation resulted in a further decrease in the number of binocularly driven cells and an increase in unresponsive cells. However, it did not produce a bias in favor of the open eye in terms of either ocular dominance or orientation selectivity. In DR(2) cats there was a high incidence of unresponsive cells and a marked loss of binocularly driven cells after the rearing period. Subsequent monocular deprivation failed to produce any significant changes.(ABSTRACT TRUNCATED AT 400 WORDS)

Cholinergic and noradrenergic afferents influence the functional properties of the postnatal visual cortex in rats

1999 ◽  
Vol 16 (6) ◽  
pp. 1015-1028 ◽  
Author(s):  
ROSITA SICILIANO ◽  
FRANCESCO FORNAI ◽  
IRENE BONACCORSI ◽  
LUCIANO DOMENICI ◽  
PAOLA BAGNOLI
Keyword(s):  
Visual Cortex ◽  
Functional Properties ◽  
Cortical Neurons ◽  
Developmental Plasticity ◽  
Signal To Noise Ratio ◽  
Ocular Dominance ◽  
Field Size ◽  
Cortical Cells ◽  
Visual Cortical ◽  
Na Depletion

Based on previous evidence that acetylcholine (ACh) and noradrenaline (NA) play a permissive role in developmental plasticity in the kitten visual cortex, we reinvestigated this topic in the postnatal visual cortex of rats with normal vision. In rats, the functional properties of visual cortical cells develop gradually between the second and the sixth postnatal week (Fagiolini et al., 1994). Cortical cholinergic depletion, by basal forebrain (BF) lesions at postnatal day (PD) 15 (eye opening), leads to a transient disturbance in the distribution of ocular dominance (Siciliano et al., 1997). In the present study, we investigated the development of visual cortical response properties following cytotoxic lesions of the locus coeruleus (LC) alone or in combination with lesions of cholinergic BF. The main result is that early NA depletion impairs the orientation selectivity of cortical neurons, causes a slight increase of their receptive-field size, and reduces the signal-to-noise ratio of cell responses. Similar effects are obtained following NA depletion in adult animals, although the effects of adult noradrenergic deafferentation are significantly more severe than those obtained after early NA depletion. Additional cholinergic depletion causes an additional transient change in ocular-dominance distribution similarly to that obtained after cholinergic deafferentation alone. Comparisons between depletion of NA on the one hand and depletion of both NA and ACh on the other suggest that the effects of combined deafferentation on the functional properties studied result from simple linear addition of the effects of depleting each afferent system alone.

Effect of dark rearing on the volume of visual cortex (areas 17 and 18) and number of visual cortical cells in young kittens

1992 ◽  
Vol 32 (3) ◽  
pp. 449-459 ◽  
Author(s):  
József Takács ◽  
P. Saillour ◽  
M. Imbert ◽  
M. Bogner ◽  
J. Hámori
Keyword(s):  
Visual Cortex ◽  
Cortical Cells ◽  
Areas 17 And 18 ◽  
Visual Cortical ◽  
Dark Rearing

scholarly journals No on-off Maps in Supragranular Layers of Ferret Visual Cortex

2002 ◽  
Vol 88 (4) ◽  
pp. 2163-2166 ◽  
Author(s):  
Barbara Chapman ◽  
Imke Gödecke
Keyword(s):  
Visual Cortex ◽  
Ocular Dominance ◽  
Receptive Fields ◽  
Visual Space ◽  
Cortical Layer ◽  
Cortical Function ◽  
Cortical Cells ◽  
Cortical Inputs ◽  
Cortical Receptive Fields ◽  
Visual Cortical

Primary visual cortex contains functional maps of a number of stimulus properties including ocular dominance, orientation, direction, color, and spatial frequency. These maps must be organized with respect to each other and to a single continuous retinotopic map of visual space such that each stimulus parameter is represented at each point in space. In the ferret, geniculo-cortical inputs to cortical layer IV are segregated into on- andoff-center patches, suggesting the possibility that there might be an additional cortical map in this species. We have used optical imaging of intrinsic signals to search for on-offmaps in ferret visual cortical cells and have found none. This suggests that the high degree of on-off segregation seen subcortically in the ferret may play a role in the development of visual cortical receptive fields rather than in adult cortical function.

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