scholarly journals Dark Rearing Promotes the Recovery of Visual Cortical Responses but Not the Morphology of Geniculocortical Axons in Amblyopic Cat

2021 ◽  
Vol 15 ◽  
Author(s):  
Takahiro Gotou ◽  
Katsuro Kameyama ◽  
Ayane Kobayashi ◽  
Kayoko Okamura ◽  
Takahiko Ando ◽  
...  
Keyword(s):  
Visual Cortex ◽  
Cortical Neurons ◽  
Visual Pathway ◽  
Monocular Deprivation ◽  
Postnatal Life ◽  
Visual Neurons ◽  
Cortical Responses ◽  
Soma Size ◽  
Visual Cortical ◽  
Dark Rearing

Monocular deprivation (MD) of vision during early postnatal life induces amblyopia, and most neurons in the primary visual cortex lose their responses to the closed eye. Anatomically, the somata of neurons in the closed-eye recipient layer of the lateral geniculate nucleus (LGN) shrink and their axons projecting to the visual cortex retract. Although it has been difficult to restore visual acuity after maturation, recent studies in rodents and cats showed that a period of exposure to complete darkness could promote recovery from amblyopia induced by prior MD. However, in cats, which have an organization of central visual pathways similar to humans, the effect of dark rearing only improves monocular vision and does not restore binocular depth perception. To determine whether dark rearing can completely restore the visual pathway, we examined its effect on the three major concomitants of MD in individual visual neurons, eye preference of visual cortical neurons and soma size and axon morphology of LGN neurons. Dark rearing improved the recovery of visual cortical responses to the closed eye compared with the recovery under binocular conditions. However, geniculocortical axons serving the closed eye remained retracted after dark rearing, whereas reopening the closed eye restored the soma size of LGN neurons. These results indicate that dark rearing incompletely restores the visual pathway, and thus exerts a limited restorative effect on visual function.

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)

Development of the visual callosal cell distribution in the rat: Mature features are present at birth

1996 ◽  
Vol 13 (5) ◽  
pp. 923-943 ◽  
Author(s):  
Cynthia S. Hernit ◽  
Kathryn M. Murphy ◽  
Richard C. van Sluyters
Keyword(s):  
Visual Cortex ◽  
Cortical Neurons ◽  
Occipital Cortex ◽  
The Body ◽  
Neonatal Rat ◽  
Postnatal Life ◽  
Opposite Hemisphere ◽  
Rat Pups ◽  
Cortical Gray Matter ◽  
Visual Cortical

AbstractIn the present study, the early postnatal distribution and subsequent fate of visual callosal neurons were studied in neonatal rat pups. Previous studies had indicated that the adult pattern of visual callosal neurons was sculpted from an initially uniform distribution in the neonatal cortex. To reexamine this issue, we used a sensitive tracer, latex microspheres conjugated either to rhodamine or fluorescein, that was injected into the occipital cortex of one hemisphere in pups on the day of birth (PND 1), PND 6, or PND 12. Examination of the resulting retrograde labeling of cortical neurons in the opposite hemisphere indicates that features of the mature visual callosal pattern are present as early as PND 1. At all stages of postnatal development, the relative density of callosal projection cells varies consistently across the mediolateral extent of primary visual cortex —it is always highest in the region of the 17/18a border and lowest in the body of area 17. These data strongly suggest that, from the outset, visual cortical neurons in the region of the 17/18a border preferentially make connections with the opposite hemisphere. The results of experiments in which callosal neurons were labeled on the day of birth indicate that only those neurons that have migrated to their final cortical destinations have extended callosal axons into the vicinity of the visual cortex in the opposite hemisphere. The initial pattern of callosal neurons resembles a dense, compact version of the mature one, and the present study suggests that much of the remaining change in the appearance of this pathway may be accounted for by the decrease in the overall density of neurons that is due to expansion of the cortical gray matter during postnatal life. Taken together, these results suggest that the development of the visual callosal pathway in the rat may be more similar to that in the monkey than has been reported previously.

scholarly journals The Development of Active Binocular Vision under Normal and Alternate Rearing Conditions

2020 ◽  
Author(s):  
Lukas Klimmasch ◽  
Johann Schneider ◽  
Alexander Lelais ◽  
Bertram E. Shi ◽  
Jochen Triesch
Keyword(s):  
Visual Cortex ◽  
Binocular Vision ◽  
Cortical Neurons ◽  
Orientation Tuning ◽  
Active Perception ◽  
Efficient Coding ◽  
Rearing Conditions ◽  
Active Binocular Vision ◽  
Experimental Findings ◽  
Visual Cortical

AbstractThe development of binocular vision is an active learning process comprising the development of disparity tuned neurons in visual cortex and the establishment of precise vergence control of the eyes. We present a computational model for the learning and self-calibration of active binocular vision based on the Active Efficient Coding framework, an extension of classic efficient coding ideas to active perception. Under normal rearing conditions, the model develops disparity tuned neurons and precise vergence control, allowing it to correctly interpret random dot stereogramms. Under altered rearing conditions modeled after neurophysiological experiments, the model qualitatively reproduces key experimental findings on changes in binocularity and disparity tuning. Furthermore, the model makes testable predictions regarding how altered rearing conditions impede the learning of precise vergence control. Finally, the model predicts a surprising new effect that impaired vergence control affects the statistics of orientation tuning in visual cortical neurons.

scholarly journals Critical periods in amblyopia

2018 ◽  
Vol 35 ◽  
Author(s):  
TAKAO K. HENSCH ◽  
ELIZABETH M. QUINLAN
Keyword(s):  
Visual Cortex ◽  
Critical Period ◽  
Molecular Mechanisms ◽  
Ocular Dominance ◽  
Molecular Genetic ◽  
Monocular Deprivation ◽  
Critical Periods ◽  
Developmental Constraints ◽  
Early Postnatal Development ◽  
Visual Cortical

AbstractThe shift in ocular dominance (OD) of binocular neurons induced by monocular deprivation is the canonical model of synaptic plasticity confined to a postnatal critical period. Developmental constraints on this plasticity not only lend stability to the mature visual cortical circuitry but also impede the ability to recover from amblyopia beyond an early window. Advances with mouse models utilizing the power of molecular, genetic, and imaging tools are beginning to unravel the circuit, cellular, and molecular mechanisms controlling the onset and closure of the critical periods of plasticity in the primary visual cortex (V1). Emerging evidence suggests that mechanisms enabling plasticity in juveniles are not simply lost with age but rather that plasticity is actively constrained by the developmental up-regulation of molecular ‘brakes’. Lifting these brakes enhances plasticity in the adult visual cortex, and can be harnessed to promote recovery from amblyopia. The reactivation of plasticity by experimental manipulations has revised the idea that robust OD plasticity is limited to early postnatal development. Here, we discuss recent insights into the neurobiology of the initiation and termination of critical periods and how our increasingly mechanistic understanding of these processes can be leveraged toward improved clinical treatment of adult amblyopia.

scholarly journals Postnatal Development of Onset Transient Responses in Macaque V1 and V2 Neurons

2008 ◽  
Vol 100 (3) ◽  
pp. 1476-1487 ◽  
Author(s):  
Bin Zhang ◽  
Earl L. Smith ◽  
Yuzo M. Chino
Keyword(s):  
Visual Cortex ◽  
Eye Movements ◽  
Primary Visual Cortex ◽  
Cortical Neurons ◽  
Newborn Infants ◽  
Neuronal Firing ◽  
Transient Responses ◽  
Visual Cortical ◽  
Better Than

Vision of newborn infants is limited by immaturities in their visual brain. In adult primates, the transient onset discharges of visual cortical neurons are thought to be intimately involved with capturing the rapid succession of brief images in visual scenes. Here we sought to determine the responsiveness and quality of transient responses in individual neurons of the primary visual cortex (V1) and visual area 2 (V2) of infant monkeys. We show that the transient component of neuronal firing to 640-ms stationary gratings was as robust and as reliable as in adults only 2 wk after birth, whereas the sustained component was more sluggish in infants than in adults. Thus the cortical circuitry supporting onset transient responses is functionally mature near birth, and our findings predict that neonates, known for their “impoverished vision,” are capable of initiating relatively mature fixating eye movements and of performing in detection of simple objects far better than traditionally thought.

scholarly journals Gene Expression Patterns Underlying the Reinstatement of Plasticity in the Adult Visual System

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Ettore Tiraboschi ◽  
Ramon Guirado ◽  
Dario Greco ◽  
Petri Auvinen ◽  
Jose Fernando Maya-Vetencourt ◽  
...  
Keyword(s):  
Gene Expression ◽  
Visual Cortex ◽  
Large Scale ◽  
Molecular Mechanisms ◽  
Expression Patterns ◽  
Monocular Deprivation ◽  
Adult Brain ◽  
Gene Expression Patterns ◽  
Postnatal Life ◽  
Critical Periods

The nervous system is highly sensitive to experience during early postnatal life, but this phase of heightened plasticity decreases with age. Recent studies have demonstrated that developmental-like plasticity can be reactivated in the visual cortex of adult animals through environmental or pharmacological manipulations. These findings provide a unique opportunity to study the cellular and molecular mechanisms of adult plasticity. Here we used the monocular deprivation paradigm to investigate large-scale gene expression patterns underlying the reinstatement of plasticity produced by fluoxetine in the adult rat visual cortex. We found changes, confirmed with RT-PCRs, in gene expression in different biological themes, such as chromatin structure remodelling, transcription factors, molecules involved in synaptic plasticity, extracellular matrix, and excitatory and inhibitory neurotransmission. Our findings reveal a key role for several molecules such as the metalloproteases Mmp2 and Mmp9 or the glycoprotein Reelin and open up new insights into the mechanisms underlying the reopening of the critical periods in the adult brain.

Functional postnatal development of the rat primary visual cortex and the role of visual experience: Dark rearing and monocular deprivation

1994 ◽  
Vol 34 (6) ◽  
pp. 709-720 ◽  
Author(s):  
Michela Fagiolini ◽  
Tommaso Pizzorusso ◽  
Nicoletta Berardi ◽  
Luciano Domenici ◽  
Lamberto Maffei
Keyword(s):  
Visual Cortex ◽  
Postnatal Development ◽  
Primary Visual Cortex ◽  
Visual Experience ◽  
Monocular Deprivation ◽  
Dark Rearing

Excitatory amino acid receptor-mediated transmission in geniculocortical and intracortical pathways within visual cortex

1991 ◽  
Vol 66 (1) ◽  
pp. 293-306 ◽  
Author(s):  
L. J. Larson-Prior ◽  
P. S. Ulinski ◽  
N. T. Slater
Keyword(s):  
Visual Cortex ◽  
Amino Acid ◽  
Cortical Neurons ◽  
Excitatory Amino Acid ◽  
Nmda Antagonist ◽  
Receptor Subtypes ◽  
Excitatory Amino Acid Receptor ◽  
Visual Cortical ◽  
Stimulation Of

1. A preparation of turtle (Chrysemys picta and Pseudemys scripta) brain in which the integrity of the intracortical and geniculocortical pathways in visual cortex are maintained in vitro has been used to differentiate the excitatory amino acid (EAA) receptor subtypes involved in geniculocortical and intracortical synapses. 2. Stimulation of the geniculocortical fibers at subcortical loci produces monosynaptic excitatory postsynaptic potentials (EPSPs) in visual cortical neurons. These EPSPs are blocked by the broad-spectrum EAA receptor antagonist kynurenate (1-2 mM) and the non-N-methyl-D-aspartate (NMDA) antagonist 6, 7-dinitroquinoxaline-2,3-dione (DNQX, 10 microM), but not by the NMDA antagonist D,L-2-amino-5-phosphonovalerate (D,L-AP-5, 100 microM). These results indicate that the geniculocortical EPSP is mediated by EAAs that access principally, if not exclusively, EAA receptors of the non-NMDA subtypes. 3. Stimulation of intracortical fibers evokes compound EPSPs that could be resolved into three components differing in latency to peak. The component with the shortest latency was not affected by any of the EAA-receptor antagonists tested. The second component, of intermediate latency, was blocked by kyurenate and DNQX but not by D,L-AP-5. The component of longest latency was blocked by kynurenate and D,L-AP-5, but not by DNQX. These results indicate that the compound intracortical EPSP is comprised of three pharmacologically distinct components that are mediated by an unknown receptor, by quisqualate/kainate, and by NMDA receptors, respectively. 4. Repetitive stimulation of intracortical pathways at 0.33 Hz produces a dramatic potentiation of the late, D,L-AP-5-sensitive component of the intracortical EPSP. 5. These experiments lead to a hypothesis about the subtypes of EAA receptors that are accessed by the geniculocortical and intracortical pathways within visual cortex.

scholarly journals IGF-1 Restores Visual Cortex Plasticity in Adult Life by Reducing Local GABA Levels

2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
José Fernando Maya-Vetencourt ◽  
Laura Baroncelli ◽  
Alessandro Viegi ◽  
Ettore Tiraboschi ◽  
Eero Castren ◽  
...  
Keyword(s):  
Nervous System ◽  
Visual Cortex ◽  
Neural Plasticity ◽  
Cortical Neurons ◽  
Environmental Enrichment ◽  
Adult Life ◽  
Monocular Deprivation ◽  
Adult Brain ◽  
Environmental Stimulation ◽  
The Central Nervous System

The central nervous system architecture is markedly modified by sensory experience during early life, but a decline of plasticity occurs with age. Recent studies have challenged this dogma providing evidence that both pharmacological treatments and paradigms based on the manipulation of environmental stimulation levels can be successfully employed as strategies for enhancing plasticity in the adult nervous system. Insulin-like growth factor 1 (IGF-1) is a peptide implicated in prenatal and postnatal phases of brain development such as neurogenesis, neuronal differentiation, synaptogenesis, and experience-dependent plasticity. Here, using the visual system as a paradigmatic model, we report that IGF-1 reactivates neural plasticity in the adult brain. Exogenous administration of IGF-1 in the adult visual cortex, indeed, restores the susceptibility of cortical neurons to monocular deprivation and promotes the recovery of normal visual functions in adult amblyopic animals. These effects were accompanied by a marked reduction of intracortical GABA levels. Moreover, we show that a transitory increase of IGF-1 expression is associated to the plasticity reinstatement induced by environmental enrichment (EE) and that blocking IGF-1 action by means of the IGF-1 receptor antagonist JB1 prevents EE effects on plasticity processes.

scholarly journals How the mechanisms of long-term synaptic potentiation and depression serve experience-dependent plasticity in primary visual cortex

2014 ◽  
Vol 369 (1633) ◽  
pp. 20130284 ◽  
Author(s):  
Sam F. Cooke ◽  
Mark F. Bear
Keyword(s):  
Visual Cortex ◽  
Primary Visual Cortex ◽  
Visual Learning ◽  
Excitatory Input ◽  
Monocular Deprivation ◽  
Hebbian Plasticity ◽  
Circuit Components ◽  
Cortical Synapses ◽  
Visual Cortical

Donald Hebb chose visual learning in primary visual cortex (V1) of the rodent to exemplify his theories of how the brain stores information through long-lasting homosynaptic plasticity. Here, we revisit V1 to consider roles for bidirectional ‘Hebbian’ plasticity in the modification of vision through experience. First, we discuss the consequences of monocular deprivation (MD) in the mouse, which have been studied by many laboratories over many years, and the evidence that synaptic depression of excitatory input from the thalamus is a primary contributor to the loss of visual cortical responsiveness to stimuli viewed through the deprived eye. Second, we describe a less studied, but no less interesting form of plasticity in the visual cortex known as stimulus-selective response potentiation (SRP). SRP results in increases in the response of V1 to a visual stimulus through repeated viewing and bears all the hallmarks of perceptual learning. We describe evidence implicating an important role for potentiation of thalamo-cortical synapses in SRP. In addition, we present new data indicating that there are some features of this form of plasticity that cannot be fully accounted for by such feed-forward Hebbian plasticity, suggesting contributions from intra-cortical circuit components.

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