Effects of vasoactive intestinal polypeptide on the response properties of cells in area 17 of the cat visual cortex

1993 ◽  
Vol 69 (5) ◽  
pp. 1465-1474 ◽  
Author(s):  
P. C. Murphy ◽  
K. L. Grieve ◽  
A. M. Sillito
Keyword(s):  
Visual Cortex ◽  
Spontaneous Activity ◽  
Vasoactive Intestinal Polypeptide ◽  
Signal To Noise Ratio ◽  
Response Magnitude ◽  
Visual Response ◽  
Area 17 ◽  
Signal To Noise ◽  
Cortical Cells ◽  
Cholinergic Agonist

1. Vasoactive intestinal polypeptide (VIP) was iontophoretically applied to a population of 90 single cells in the primary visual cortex (area 17) of the cat. Response magnitude, response selectivity, spontaneous activity, and the ratio between the visual response and spontaneous activity (signal-to-noise ratio) of the cells were assessed quantitatively before and during drug application. 2. VIP had little effect in the absence of visual stimulation, with only 29/90 (32%) of the cells showing a change of even 1 sp/s in their spontaneous activity. In contrast it had a clear effect on the visual responses of the majority (73/90, 81%) of the cells tested. 3. VIP produced a substantial change (i.e., > or = 40%) in optimal response magnitude for 57 of the affected cells. Of these 65% were facilitated, usually with no change or an improvement in signal-to-noise ratio and direction selectivity. The remaining cells were inhibited, with more variable effects on their visual response characteristics, and were found predominantly in the superficial laminae. 4. The effects of VIP bore a remarkable resemblance to those reported previously for the muscarinic action of acetylcholine (ACh). VIP and a muscarinic cholinergic agonist, either ACh or acetyl-beta-methacholine (MeCh), were therefore applied in turn to a group of 40 cells. In 23 cases VIP and the muscarinic agonist were also applied simultaneously. 5. The effects of VIP and the cholinergic agonist matched in 92% of the cases where both drugs were effective. That is to say, cells that were facilitated by VIP were facilitated also by ACh or MeCh, and vice versa. In many instances there was a clear similarity in the pattern as well as the direction of the effects produced by the two substances. The result of simultaneous application was generally additive. 6. These data suggest that VIP and ACh activate very similar postsynaptic mechanisms, and share a closely related function at the level of individual cortical cells. Thus VIP may facilitate the responses of both the excitatory and the inhibitory components of the cortical circuit, leading to an overall increase in responsiveness and selectivity. In contrast to the cholinergic input from the basal forebrain, however, the VIP-positive cortical cells are likely to exert a very localized influence, over a circumscribed region of the cortex, in response to the presence of an effective visual stimulus.

Activation of Group III mGluRs increases the activity of neurons in area 17 of the cat

2002 ◽  
Vol 19 (3) ◽  
pp. 355-364 ◽  
Author(s):  
C.J. BEAVER ◽  
Q-H. JI ◽  
X-T. JIN ◽  
N.W. DAW
Keyword(s):  
Visual Cortex ◽  
Spontaneous Activity ◽  
Metabotropic Glutamate Receptors ◽  
Visual Stimulation ◽  
Visual Response ◽  
Area 17 ◽  
Group Iii ◽  
Metabotropic Glutamate

Activation of Group III metabotropic glutamate receptors (mGluRs) by L(+)-2-amino-4-phosphonobutyric acid (L-AP4) has different effects on in vitro slice preparations of visual cortex (Jin & Daw, 1998) as compared with in vivo recordings from somatosensory cortex (Wan & Cahusac, 1995). To investigate the role of Group III mGluRs in the cat visual cortex, in vivo recordings were made of neurons in area 17 of the visual cortex of kittens and adult cats at different ages and the effect of iontophoretic application of L-AP4 (100 mM) was examined. Application of L-AP4 resulted in an increase of the spontaneous activity and visual response of neurons to visual stimulation, the former more than the latter. The effect of L-AP4 was greatest at 3–5 weeks of age with the effect on the visual response declining more rapidly than the effect on spontaneous activity. Consistent with work in rat cortex (Jin & Daw, 1998), the effect of L-AP4 was significantly greater in upper and lower layers than in middle layers. Whole-cell in vitro recordings from slices of rat visual cortex indicated that L-AP4 (50 mM) did not increase the number of spikes elicited by increasing levels of current injections. These results confirm that L-AP4 increases activity in vivo and reasons for the discrepancy with the in vitro results are discussed.

Effect of longer periods of dark rearing on NMDA receptors in cat visual cortex

1994 ◽  
Vol 72 (3) ◽  
pp. 1220-1226 ◽  
Author(s):  
D. Czepita ◽  
S. N. Reid ◽  
N. W. Daw
Keyword(s):  
Visual Cortex ◽  
Nmda Receptor ◽  
Firing Rate ◽  
Spontaneous Activity ◽  
Visual Response ◽  
Visual Responses ◽  
Level Of Activity ◽  
Direction Of Movement ◽  
Excitatory Drive ◽  
Dark Rearing

1. Cats were reared in the dark to 3, 5, and 11 mo. We studied the N-methyl-D-aspartate (NMDA) receptor contribution to the visual response in the cortex, defined as the percentage reduction in visual response after application of 2-amino-5-phosphonovaleric acid (APV). We also studied the firing rate in response to the optimal visual stimulus and the spontaneous activity. We made comparisons of all these properties between light-reared and dark-reared animals. 2. The NMDA receptor contribution to the visual response in layers IV, V, and VI of dark-reared animals was substantially above that in light-reared animals at all ages tested. 3. The specificity of receptive field properties in dark-reared animals showed some degeneration between 6 wk and 3 mo of age. At > or = 3 mo, almost no cells were specific for orientation and direction of movement. 4. Firing rate was lower in dark-reared animals at all ages, suggesting a decrease in excitatory drive to the visual cortex. 5. Spontaneous activity was equal in dark- and light-reared animals, suggesting that the overall level of activity (including visual responses as well as spontaneous activity) in light-reared animals is higher than in dark-reared animals. This should tend to upregulate glutamate receptors in general in dark-reared animals.

Binocular competition affects the pattern and intensity of ocular activation columns in the visual cortex of cats

1989 ◽  
Vol 2 (4) ◽  
pp. 391-407 ◽  
Author(s):  
N. Tumosa ◽  
S. B. Tieman ◽  
D. G. Tieman
Keyword(s):  
Visual Cortex ◽  
Competitive Advantage ◽  
Monocular Deprivation ◽  
Area 17 ◽  
Large Area ◽  
Cortical Cells ◽  
Areas 17 And 18 ◽  
Binocular Competition ◽  
Video Densitometry ◽  
Average Size

AbstractThe effect of binocular competition on the development of ocular activation columns in areas 17 and 18 of cats was studied using the 14C-2-deoxyglucose (14C-2DG) technique to visualize the regions of cortex activated by one eye in cats reared with equal alternating monocular exposure (equal AME), unequal AME, or monocular deprivation (MD). The average size of the ocular activation columns of the eye stimulated during administration of 2DG was positively correlated with the competitive advantage during rearing. In order of increasing percentage of visual cortex activated, the eyes were (1) deprived eye of MD cats, (2) less experienced eye of unequal AME cats, (3) either eye of equal AME cats, (4) more experienced eye of unequal AME cats, and (5) experienced eye of MD cats. In area 17, the shape of the activation columns also was affected by the relative experience of the eye. The columns of the deprived eye of MD cats were widest in layer IV, where they were about the same width as those of the less experienced eye of the unequal AME cats; in other layers they were narrower, sometimes disappearing altogether. In contrast, the activation columns of the less experienced eye of the unequal AME cats were about the same width in all layers. These results suggest that when one eye is placed at a severe disadvantage and receives no patterned input, as in MD, both geniculocortical connections and intracortical connections may be disrupted, but when the disadvantage is less, as in unequal AME, only the geniculocortical connections are disrupted.Binocular competition also affected the intensity of activation within columns in area 17. We used video densitometry to determine ratios of the amount of label in cortical and thalamic structures. Both the ratio of label in area 17 to that in the lateral geniculate nucleus (LGN) and the ratio of label in the binocular segment of area 17 to that in the monocular segment were significantly less for the deprived eye of MD cats than for any other group. These results suggest that even within the smaller activation columns, deprived geniculocortical afferents are relatively ineffective at driving cortical cells. This finding is consistent with earlier reports that the synapses from the deprived pathway are both morphologically abnormal and reduced in number. The cortical labeling for the less experienced eye of the unequal AME cats and the experienced eye of the MD cats were also significantly less than that in equal AME cats. The decreased labeling for the experienced eye activation columns suggests that, in order to cover an abnormally large area, afferents representing the experienced eye must make fewer synaptic contacts within that area and that there are intrinsic limits on the number of synapses that one axon can make.

scholarly journals Neuronal adaptation reveals a suboptimal decoding of orientation tuned populations in the mouse visual cortex

2018 ◽  
Author(s):  
Miaomiao Jin ◽  
Jeffrey M. Beck ◽  
Lindsey L. Glickfeld
Keyword(s):  
Visual Cortex ◽  
Visual System ◽  
Cortical Neurons ◽  
Signal To Noise Ratio ◽  
Sensory Information ◽  
Orientation Discrimination ◽  
Signal To Noise ◽  
Neuronal Adaptation ◽  
Related Information ◽  
Mouse Visual Cortex

AbstractSensory information is encoded by populations of cortical neurons. Yet, it is unknown how this information is used for even simple perceptual choices such as discriminating orientation. To determine the computation underlying this perceptual choice, we took advantage of the robust adaptation in the mouse visual system. We find that adaptation increases animals’ thresholds for orientation discrimination. This was unexpected since optimal computations that take advantage of all available sensory information predict that the shift in tuning and increase in signal-to-noise ratio in the adapted condition should improve discrimination. Instead, we find that the effects of adaptation on behavior can be explained by the appropriate reliance of the perceptual choice circuits on target preferring neurons, but the failure to discount neurons that prefer the distractor. This suggests that to solve this task the circuit has adopted a suboptimal strategy that discards important task-related information to implement a feed-forward visual computation.

scholarly journals The influence of evidence volatility on choice, reaction time and confidence in a perceptual decision

eLife ◽  
2016 ◽  
Vol 5 ◽  
Author(s):  
Ariel Zylberberg ◽  
Christopher R Fetsch ◽  
Michael N Shadlen
Keyword(s):  
Visual Cortex ◽  
Reaction Time ◽  
Choice Reaction Time ◽  
Signal To Noise Ratio ◽  
Stimulus Strength ◽  
Signal To Noise ◽  
Perceptual Decision ◽  
Evidence Accumulation ◽  
Decision Speed ◽  
Speed Accuracy

Many decisions are thought to arise via the accumulation of noisy evidence to a threshold or bound. In perception, the mechanism explains the effect of stimulus strength, characterized by signal-to-noise ratio, on decision speed, accuracy and confidence. It also makes intriguing predictions about the noise itself. An increase in noise should lead to faster decisions, reduced accuracy and, paradoxically, higher confidence. To test these predictions, we introduce a novel sensory manipulation that mimics the addition of unbiased noise to motion-selective regions of visual cortex, which we verified with neuronal recordings from macaque areas MT/MST. For both humans and monkeys, increasing the noise induced faster decisions and greater confidence over a range of stimuli for which accuracy was minimally impaired. The magnitude of the effects was in agreement with predictions of a bounded evidence accumulation model.

Activation of metabotropic glutamate receptors has different effects in different layers of cat visual cortex

1997 ◽  
Vol 14 (1) ◽  
pp. 83-88 ◽  
Author(s):  
Silvia N.M. Reid ◽  
Nigel W. Daw
Keyword(s):  
Visual Cortex ◽  
Dicarboxylic Acid ◽  
Glutamate Receptors ◽  
Spontaneous Activity ◽  
Primary Visual Cortex ◽  
Metabotropic Glutamate Receptors ◽  
Visual Response ◽  
Single Neurons ◽  
Metabotropic Glutamate ◽  
Cat Visual Cortex

AbstractSingle neurons were recorded in cat primary visual cortex, and the effect of iontophoresis of the metabotropic glutamate agonist 1S,3R-aminocyclopentane-1.3-dicarboxylic acid (ACPD) was observed. In nearly all cases (41/43), ACPD reduced the visual response. In some cases ACPD also reduced spontaneous activity (24/43), and in other cases ACPD increased spontaneous activity (18/43). Increases were generally seen in infragranular layers (V and VI), and decreases in supragranular layers (II and III). The reduction in the visual response was also largest in supragranular layers. We conclude that activation of metabotropic glutamate receptors has both facilitatory and depressive effects in visual cortex, and the effect depends on the layer of the cell recorded.

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.

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.

scholarly journals Variation in Spontaneous Activity and Visual Evoked Response in Primary Visual Cortex of the S334ter-3 Rats

2020 ◽  
Vol 185 ◽  
pp. 03034
Author(s):  
Bojun Hou ◽  
Ke Chen ◽  
Yilei Zhao ◽  
Leanne Lai Hang Chan
Keyword(s):  
Visual Cortex ◽  
Spontaneous Activity ◽  
Primary Visual Cortex ◽  
Dynamic Range ◽  
Signal To Noise Ratio ◽  
Evoked Responses ◽  
Visual Evoked Response ◽  
Classical Receptive Field ◽  
Narrow Dynamic Range ◽  
Visual Evoked

S334ter-3 retinal degeneration (RD) rats have been widely used to investigate degenerative diseases of the retina. In this model, morphological and electrophysiological changes have been observed in the retina, superior colliculus and primary visual cortex (V1). In this study, experimental rats (S334ter-3) carried one copy of the mutant transgene. We measured the extracellular responses in the primary visual cortex to three stimulus contrast levels (spontaneous activity, medium contrast, and high contrast) at the preferred parameters of each recorded cell under classical receptive field (CRF) stimulation. Then we compared the responses (spontaneous activity and the visual evoked responses) in RD rats with those in wildtype rats. Our results show that V1 cells in the RD group exhibit stronger spontaneous activity but weaker stimulus-evoked responses at medium and high contrasts. At the same time, compared with WT group, RD group also showed a narrow dynamic range. These results indicate the decrease in discriminating the stimuli contrast and loss in responses and lower signal to noise ratio after retina degeneration.

Effects of cholinergic depletion on neuron activities in the cat visual cortex

1987 ◽  
Vol 58 (4) ◽  
pp. 781-794 ◽  
Author(s):  
H. Sato ◽  
Y. Hata ◽  
K. Hagihara ◽  
T. Tsumoto
Keyword(s):  
Visual Cortex ◽  
Cortical Neurons ◽  
Response Magnitude ◽  
Nucleus Basalis ◽  
Visual Responses ◽  
Cortical Cells ◽  
Contralateral Cortex ◽  
Almost All ◽  
Mean Current ◽  
Cholinergic Projection

1. Unilateral lesions of the nucleus basalis magnocellularis (nBM), a source of cholinergic projection to the cerebral cortex, were produced by injection of kainic acid in the cat. The lesions caused a significant reduction in density of choline acetyltransferase-immunoreactive terminals in the visual cortex ipsilateral to the lesions. 2. In the primary visual cortex ipsilateral to the lesions [acetylcholine (ACh)-depleted cortex], about half of the cells had weak or undetectable visual responses, whereas in the contralateral visual cortex almost all the cells had normal responsivity. The response selectivity, such as orientation and direction selectivities, of cortical cells was not affected by the depletion of ACh. 3. The microionophoretic application of ACh to cells under observation facilitated visual responses in 83% of the cells recorded from the ACh-depleted cortex, whereas it suppressed the responses in only 9%. The application of a muscarinic antagonist, atropine, to cells in the ACh-depleted cortex was ineffective, suggesting no residual ACh activity. 4. The mean current required to induce facilitation in the cortex ipsilateral to the lesion was significantly smaller than that required in the contralateral cortex and the visual cortex of the normal cat, suggesting a supersensitivity of receptors mediating the effect or a reduction in catabolism of exogenous ACh in the ACh-depleted cortex. 5. More than half of the cells that had been unresponsive to visual stimuli became clearly responsive during the ACh application. The response magnitude of cortical cells, as a whole, increased to the same degree as that observed during the ACh application in the normal cat. 6. In addition to the decrease in the average response magnitude, there was a remarkable variability in responses of cells to motion of the slit from sweep to sweep in the ACh-depleted cortex. The application of ACh to cortical cells decreased the variability of responses and consequently made the responses much more consistent. 7. These results suggest that without ACh supplied from the nBM, most of the cortical neurons could not respond briskly and consistently to excitatory inputs and that exogenously applied ACh could reverse such an impairment of cortical neurons through intact or even supersensitive postsynaptic receptors.

Sign in / Sign up

Export Citation Format

Share Document