Temporal coding in the visual cortex: new vistas on integration in the nervous system

Engel, Andreas K.; König, Peter; Kreiter, Andreas K.; Schillen, Thomas B.; Singer, Wolf

doi:10.1016/0166-2236(92)90039-b

Cited by 666 publications

(309 citation statements)

References 20 publications

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“…The value of the frequency T is determined by setting the scale of time for the graph; the other parameters, which define the neuron firing pattern, are the average time between bursts T b and the burst duration δT and their values are consistent with the neuron firing pattern observed for the alert cat (Engel et al, 1992;Gray and Singer, 1989;Singer and Gray, 1995) Figure 5 Comparison of the theoretical distribution of dominance duration (solid line) with the data from subjects under the influence of the hallucinogen LSD. The theoretical curve is obtained using T = 2.0sec, T b = 0.25sec and…”

Section: Results and Comparison With Experiments A Probability DImentioning

confidence: 79%

Quantum formalism to describe binocular rivalry

Manousakis

2009

Biosystems

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On the basis of the general character and operation of the process of perception, a formalism is sought to mathematically describe the subjective or abstract/mental process of perception. It is shown that the formalism of orthodox quantum theory of measurement, where the observer plays a key role, is a broader mathematical foundation which can be adopted to describe the dynamics of the subjective experience. The mathematical formalism describes the psychophysical dynamics of the subjective or cognitive experience as communicated to us by the subject. Subsequently, the formalism is used to describe simple perception processes and, in particular, to describe the probability distribution of dominance duration obtained from the testimony of subjects experiencing binocular rivalry. Using this theory and parameters based on known values of neuronal oscillation frequencies and firing rates, the calculated probability distribution of dominance duration of rival states in binocular rivalry under various conditions is found to be in good agreement with available experimental data. This theory naturally explains an observed marked increase in dominance duration in binocular rivalry upon periodic interruption of stimulus and yields testable predictions for the distribution of perceptual alteration in time.

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Section: Results and Comparison With Experiments A Probability DImentioning

confidence: 79%

Quantum formalism to describe binocular rivalry

Manousakis

2009

Biosystems

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“…This synchronization has been observed at the slow time scale of fMRI signals in the form of coherent variations in gamma-band power (48), plus gamma-band activity has been related to cortical integration of information (49,50) and can be closely linked to signals measured in BOLD fMRI (51). However, precise characterization of the underlying mechanisms awaits further research.…”

Section: Discussionmentioning

confidence: 99%

Attentional integration between anatomically distinct stimulus representations in early visual cortex

Haynes

Tregellas

Rees

2005

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

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Vision often requires attending to, and integrating information from, distant parts of the visual field. However, the neural basis for such long-range integration is not clearly understood. Here, we demonstrate a specific neural signature of attentional integration between stimuli in different parts of the visual field. Using functional MRI, we found that a task requiring the integration of information between two attended but spatially separated stimuli actively modulated the degree of functional integration (in terms of effective connectivity) between their retinotopic representations in visual cortical areas V1, V2, and V4. Spatial attention enhanced long-distance coupling between distinct neuronal populations that represented the attended visual stimuli, even at the earliest stages of cortical processing. In contrast, unattended stimulus representations were decoupled both from attended representations and particularly strongly from each other. Furthermore, enhanced functional integration between cortical representations was associated with enhanced behavioral performance. Attention may thus serve to ''bind'' together cortical loci at multiple levels of the visual hierarchy that are commonly involved in processing attended stimuli, promoting integration between otherwise functionally isolated cortical loci.attention ͉ connectivity ͉ dynamic causal modeling ͉ functional MRI ͉ vision V ision often requires integration of information from distant locations within the visual field, but how this integration is achieved is currently not well understood. Receptive field properties of visually responsive cortical neurons suggest that, in early visual cortex, information is analyzed largely (although not entirely) locally, with further processing stages combining information from successively larger portions of the visual field (1-3). In such an anatomically convergent pathway, integration of information from distant positions within the visual field might occur entirely in higher visual areas, which have large receptive fields and corresponding possibilities for interactions between distant regions (1-3). However, response properties of cells in early visual areas are also modulated by remote stimuli presented far beyond their classical receptive fields (4-7). Thus, an alternate possibility is that a neural signature reflecting integration of distant information might already be identifiable in very early visual cortex. Possible anatomical substrates for such interactions include long-range horizontal projections within visual areas (8-10), the dense and reciprocal connections between visual areas (7,(11)(12)(13)(14)(15), and subcortical pathways via pulvinar and superior colliculus (16).Here, we used functional MRI (fMRI) in humans to test whether task-dependent interactions between stimulus representations in distant parts of the visual field could be seen in early retinotopic cortex. We placed stimuli in four well separated locations of the visual field and required participants to attend to and integrate informa...

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“…This observation calls for a neuronal mechanism, often referred to as binding (Treisman, 1999;Treisman and Gelade, 1980;Zimmer et al, 2006), allowing for integration of distributed information in the service of cognitive functions (e.g., Ballard et al, 1983;Barlow, 1972;Von der Malsburg, 1981). Several authors suggested that such a mechanism could be implemented in the brain via temporally synchronized firing patterns of neuronal assemblies (Engel et al, 1992;Fries, 2005;Jensen, 2006;Lisman, 2005;Singer and Gray, 1995;Singer et al, 1996). Although not undisputed (e.g., Palanca and DeAngelis, 2005;Shadlen and Movshon, 1999), the binding theory has received support from studies of intracranial recordings that revealed that groups of activated neurons tend to synchronize in the gamma-frequency band (30-100 Hz).…”

Section: Introductionmentioning

confidence: 99%

“…Although not undisputed (e.g., Palanca and DeAngelis, 2005;Shadlen and Movshon, 1999), the binding theory has received support from studies of intracranial recordings that revealed that groups of activated neurons tend to synchronize in the gamma-frequency band (30-100 Hz). Gamma-band synchronization has been linked to several cognitive functions in a range of studies (see Engel et al, 1992Herrmann et al, 2004;Singer and Gray, 1995;Tallon-Baudry, 2003;Tallon-Baudry and Bertrand, 1999 for reviews). Furthermore, it has been shown that the precise timing of pre-and post-synaptic activation determines long-term changes in synaptic strength (Bi and Poo, 1998;Markram et al, 1997) and that synchronization of synaptic inputs in the gamma band directly enhances their effective synaptic strength (König et al, 1996;Salinas and Sejnowski, 2001).…”

Section: Introductionmentioning

confidence: 99%

EEG gamma-band synchronization in visual coding from childhood to old age: Evidence from evoked power and inter-trial phase locking

Werkle‐Bergner

Shing

Müller

et al. 2009

Clinical Neurophysiology

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a b s t r a c tObjective: To investigate lifespan age differences in neuronal mechanisms of visual coding in the context of perceptual discrimination. Methods: We recorded EEG from 17 children (10-12 years), 16 younger adults (20-26 years), and 17 older adults (70-76 years) during a simple choice-reaction task requiring discrimination of squares and circles of different sizes. We examined age-group differences in the effect of stimulus size on early ERP components, evoked gamma-band power, and inter-trial phase-stability in the gamma band as assessed by the phase-locking index (PLI). Results: In the absence of age differences in discrimination accuracy, we observed reliable age differences in patterns of ERP, evoked gamma power, and PLI. P1 and N1 peak amplitudes were larger and the peak latencies longer in children than in adults. Children also showed lower levels of evoked power and PLI than adults. Older adults showed smaller increments in evoked power with increasing stimulus size than younger adults, but similar amounts of phase locking for small-and medium-sized stimuli as younger adults. Conclusions: The relative importance of different coding mechanisms in early visual areas changes from childhood to old age. Due to synaptic overproduction and immature myelination, the visual system of children is less entrained by incoming information, resulting in less synchronized neuronal responses. Adults primarily rely on sparse representations formed through experience-dependent temporally synchronized neuronal interactions. In old age, senescent decline in neuronal density and neurotransmitter availability further increase the reliance on temporally synchronized processing. Significance: Findings from this study defy the notion that sensory aging consists in a reversal of sensory development in childhood, and point to a high degree of age specificity in mechanisms of visual coding.

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Temporal coding in the visual cortex: new vistas on integration in the nervous system

Cited by 666 publications

References 20 publications

Quantum formalism to describe binocular rivalry

Quantum formalism to describe binocular rivalry

Attentional integration between anatomically distinct stimulus representations in early visual cortex

EEG gamma-band synchronization in visual coding from childhood to old age: Evidence from evoked power and inter-trial phase locking

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