Marisa Carrasco

Psychology

Visual Perception and Attention

Go to my homepage in Psychology.

How does attention affect perception? I study the relation between the psychological and physiological mechanisms involved in basic processes of visual perception and attention. I use two main paradigms in the study of visual attention: visual search and spatial cueing.

Visual search experiments assess how efficiently observers locate a target embedded in an array of distracters. We have shown that differences in performance in visual search experiments can often be explained on the basis of elementary physiological characteristics of the visual system and physical properties of the stimuli, without having to invoke the construct of "attention", which has not always been well defined. Exploring the complex interface between perception and attention, we have elucidated the roles of practice, covert attention, and temporal dynamics in visual search.

A central line of my recent research has focused on characterizing the effects of covert attention on early visual processes. Using the spatial cueing paradigm, which enables us to manipulate spatial attention by prompting the observer to attend to a specific location, we have shown that attention interacts with perception in remarkable ways: attending to a location strengthens the representation of the signal by enhancing visual sensitivity. Moreover, by combining reaction time measurements with spatial cueing, we have established that attention not only enhances discriminability but also accelerates information accrual.

By enhancing the signal and accelerating information processing, attention improves discriminability and enables us to extract relevant information efficiently in a dynamic noisy environment.

Email: marisa.carrasco@nyu.edu

Selected Publications

Carrasco, M., Evert, D.L., Chang, I. & Katz, S.M. (1995). The eccentricity effect: Target eccentricity affects performance on conjunction searches. Perception & Psychophysics, 57 (8), 1241-1261. [pdf]

Carrasco, M. & Frieder, K.S. (1997). Cortical magnification neutralizes the eccentricity effect in visual search. Vision Research, 37 (1), 63-82. [pdf]

Carrasco, M., McLean, T.L., Katz, S.M. & Frieder, K.S. (1998). Feature asymmetries in visual search: Effects of display duration, target eccentricity, orientation & spatial frequency. Vision Research, 38 (3) 347-374. [pdf]

Yeshurun, Y. & Carrasco, M. (1998). Attention improves or impairs visual performance by enhancing spatial resolution. Nature, 396, 5 Nov. 72-75. [pdf]

McElree, B. & Carrasco, M. (1999). Temporal dynamics of visual search: A speed-accuracy analysis of feature and conjunction searches. Journal of Experimental Psychology. Human Perception & Performance, 25 (6) 1517-1539. [pdf]

Carrasco, M., Penpeci-Talgar, C. & Eckstein, M. (2000). Spatial attention increases contrast sensitivity across the CSF: Support for signal enhancement. Vision Research, 40(10-12). [pdf]

Yeshurun, Y. & Carrasco, M. (2000) The locus of attentional effects in texture segmentation. Nature Neuroscience, 3 (6) 622-627. [pdf]

Carrasco, M. & McElree, B. (2001). Covert attention accelerates the rate of visual information processing. Proceedings of the National Academy of Sciences. 98: 5363-5367.[pdf]

Carrasco M, Penpeci-Talgar C & Cameron EL (2001) Characterizing visual performance fields: Effects of transient covert attention, spatial frequency, eccentricity, task and set size. Spatial Vision 15: 61-75 [pdf]

Carrasco, M., Williams, P. E., & Yeshurun, Y. (2002). Covert attention increases spatial resolution with or without masks: Support for signal enhancement. Journal of Vision, 2(6), 467-479, [pdf], DOI 10.1167/2.6.4.

Carrasco, M., McElree, B., Denisova, K. & Giordano, A.M. (2003). Speed of visual processing increases with eccentricity. Nature Neuroscience, 6(7): 669-670.

Carrasco, M., Ling, S. & Read, S. (2004). Attention alters appearance. Nature Neuroscience. 7, 308-313.

Liu, T., Pestilli, F., & Carrasco, M. (2005) Transient attention enhances perceptual performance and fMRI response in human visual cortex. Neuron. 45, 469-477.

Ling, S., & Carrasco, M. (2006).Sustained and transient covert attention enhance the signal via different contrast response functions. Vision Research, 46, 1210-1220.

See a complete publications list