Savin C., Berkes P., Chiu C., Fiser J. & Lengyel M. (2012) Similarity between spontaneous and sensory-evoked activity does suggest learning in the cortex. SFN 2012, New Orleans, LA [Abstract]
Over development, spontaneous activity (SA) in primary visual cortex (V1) becomes increasingly similar to stimulus evoked activity (EA) (Berkes et al, Science 2011). This increasing similarity has been taken to reflect a progressive adaptation of the animal’s internal models to the statistics of the environment (Berkes et al, 2011). An alternative interpretation (Okun et al, […]
Fiser J., Savin C., Berkes P., Chiu C. & Lengyel, M. (2012) Visual experience drives the increase in similarity between spontaneous and stimulus evoked activity in V1. SFN 2012, New Orleans, LA [Abstract]
Despite ample behavioral evidence for probabilistic learning in the brain, the neural underpinnings of this process remain unclear. It has been recently hypothesized that spontaneous activity in primary sensory areas could be a marker for this learning process (Fiser et al, 2010). In this view, the increase in similarity between spontaneous and stimulus-evoked activity over […]
Popovic M., Van Hooser S. & Fiser J. (2012) Comparing functional measures of maturity in the developing ferret’s primary visual cortex. SFN 2012, New Orleans, LA [Abstract]
Traditional assessments of the development of the visual system typically use change in selectivity to particular features such as orientation or direction to determine the maturity of visual cortical circuits. Directional selectivity tuning (DS) was shown not only to increase rapidly and significantly in the two weeks after eye opening but also to exhibit clear […]
Haefner RM., Berkes P. & Fiser, J. (2012) Decision-making and attention in a sampling-based neural representations. COSYNE 2012, Frontiers in Neuroscience Conference Abstract: Neural Coding, Decision-Making & Integration in Time. [Abstract]
According to the sampling hypothesis, the activity of sensory cortex can be interpreted as drawing samples from the probability distribution over features that it implicitly represents. Perceptual inference is performed by assuming that the samples are drawn from an internal model that the brain has built of the external world (Fiser et al 2010). We […]
Orbán G., Aslin RN. & Fiser J. (2013) Statistical optimal effects of uncertainty in scene segmentation on human learning. BCCCD 2013, Budapest, Hungary [Abstract]
In contrast with the traditional deterministic view of perception, a number of recent studies have argued that it is best captured by probabilistic computations. A crucial aspect of real-world scenes is that conflicting cues render stimuli ambiguous which results in multiple hypotheses being compatible with the stimuli. Although the effects of perceptual uncertainty have been […]
Haefner RM., Berkes P. & Fiser J. (2013) Perceptual decision-making in a sampling-based neural representation. COSYNE 2013, Salt Lake City, UT [Abstract]
Most computational models of the responses of sensory neurons are based on the information in external stimuli and their feed-forward processing. Extrasensory information and top-down connections are usually incorporated on a post-hoc basis only, e.g. by postulating attentional modulations to account for features of the data that feed-forward models cannot explain. To provide a more […]
Popovic M., Haefner R. M., Lengyel M. & Fiser J. (2013) Psychophysical evidence for a sampling-based representation of uncertainty in low-level vision. COSYNE 2013, Salt Lake City, UT [Abstract]
Human and animal studies suggest that human perception can be interpreted as probabilistic inference that relies on representations of uncertainty about sensory stimuli suitable for statistically optimal decision-making and learning. It has been proposed recently that the way the brain implements probabilistic inference is by drawing samples from the posterior probability distribution, where each sample […]
Savin C., Berkes P., Chiu C., Fiser J. & Lengyel M. (2013) Similarity between spontaneous and sensory-evoked activity does suggest learning in the cortex. COSYNE 2013, Salt Lake City, UT [Abstract]
The developmental increase in similarity between spontaneous (SA) and average stimulus-evoked activity (EA) in the primary visual cortex has been suggested to reflect a progressive adaptation of the animal’s internal model to the statistics of the environment (Berkes et al., Science 2011). However, it is unknown how much of this adaptation is due to learning […]
Popovic M., Lengyel M. & Fiser J. (2013) The role of time in human decision-making. VSS 2013, Journal of Vision 13 (9), 305-305 [Abstract]
The effects of time on human decision-making are well known, yet, the precise mechanisms underlying these effects remain unclear. Under the classic signal processing framework (e.g. integration-to-bound) the passing of time allows for accumulation of evidence, parametric models of probabilistic neural representations (e.g. PPC) hold that time is used for averaging internal noise for a […]
Fiser J., Savin C., Berkes P., Chiu C. & Lengyel M. (2013) Experience-based development of internal probabilistic representations in the primary visual cortex. VSS 2013, Journal of Vision 13 (9), 600-600 [Abstract]
The developmental increase in similarity between spontaneous (SA) and average stimulus-evoked activity (EA) in the primary visual cortex has been suggested to reflect a progressive adaptation of the animal’s internal model to the statistics of the environment, a hallmark of probabilistic computation in the cortex (Berkes et al, 2011). Still, this gradual adaptation could be […]