Fatima M. Felisberti

Learn More
Face recognition algorithms perform very unreliably when the pose of the probe face is different from the gallery face: typical feature vectors vary more with pose than with identity. We propose a generative model that creates a one-to-many mapping from an idealized "identity" space to the observed data space. In identity space, the representation for each(More)
In previous work, we have shown that sudden image displacements well outside the classical receptive field modulate the visual sensitivity of LGN relay cells. Here we report the effect of image displacements on the response versus contrast function. The stimuli consisted of a central spot of optimal size and polarity (contrast range: 3-98%), flashed alone(More)
Human observers can extract a given motion direction from sets of random dots moving simultaneously in two or more directions in the same region of the visual field, a phenomenon referred to as motion transparency. As a necessary condition for separating transparent motion directions, low level encoding of local motion signals must generate frequency(More)
Visual stimulation of zones extending beyond the classical receptive field can modulate the contrast gain of neurons in the lateral geniculate nucleus (LGN) of cats, but little is known about the effect of extra-classical visual stimulation on the LGN of primates. Hence, we compare the effect of long-range interactions in parvocellular and magnocellular LGN(More)
Crowding, the difficult identification of peripherally viewed targets amidst similar distractors, has been explained as a compulsory pooling of target and distractor features. The tilt illusion, in which the difference between two adjacent gratings' orientations is exaggerated, has also been explained by pooling (of Mexican-hat-shaped population responses).(More)
The sudden displacement of the retinal image during a saccade raises the visual threshold of human observers to foveal stimuli. The fall in visual sensitivity observed during this phenomenon, known as saccadic suppression, seems to occur very early in the visual processing chain. The lateral geniculate nucleus (LGN) is a likely locus for the multiple(More)
BACKGROUND The ability to recognize the faces of potential cooperators and cheaters is fundamental to social exchanges, given that cooperation for mutual benefit is expected. Studies addressing biases in face recognition have so far proved inconclusive, with reports of biases towards faces of cheaters, biases towards faces of cooperators, or no biases at(More)
The effect of the spatial location of faces in the visual field during brief, free-viewing encoding in subsequent face recognition is not known. This study addressed this question by tagging three groups of faces with cheating, cooperating or neutral behaviours and presenting them for encoding in two visual hemifields (upper vs. lower or left vs. right).(More)