Early top-down influences on bistable perception revealed by event-related potentials

Early visual brain areas reflect the percept of an ambiguous scene

“…In monkey V4 and MT, the percentage of neurons following the dominant percept in binocular rivalry is approximately twice as large as that in V1/V2 (3), suggesting that those areas either directly influence the V1/V2 activity via the recurrent connections or share with V1/V2 some, possibly non-visual, information that alters the perceptual bias (11,12). Such steering of perception could come from brain regions involved in planning and selection of goal-directed behavior (13)(14)(15).…”

Implicit Perceptual Memory Modulates Early Visual Processing of Ambiguous Images

“…Conversely, activity in the frontal and parietal brain regions has also been associated with presentation-to-presentation perceptual alternations (Pitts et al, 2009;Sterzer et al, 2009;Pitts and Britz, 2011) and attention/mnemonic processing of sensory information (Desimone, 1996;Pasternak and Greenlee, 2005). Interestingly, ERPs derived from scalp EEGs measured during ambiguous perception are also modulated at anterior and posterior electrodes (Kornmeier and Bach, 2004Pitts et al, 2007Pitts et al, , 2008Pitts et al, , 2009Khoe et al, 2008). This is in line with the involvement of posterior and anterior regions in perceptual processing, although the inverse problem makes it hard to justify conclusions about which brain regions from which these scalp ERP modulations originate.…”

“…Therefore, we selected a posterior region and an anterior region of interest for additional analysis of the ERPs ( Fig. 1D; choice of electrodes based on Kornmeier and Bach, 2004Pitts et al, 2007Pitts et al, , 2008Pitts et al, , 2009Khoe et al, 2008). For the posterior region of interest, we averaged the signals of electrodes O1, O2, Oz, P5, P6, PO3, PO4, PO7, PO8, and POz, and for the anterior region of interest, we averaged the signals of electrodes AFz, F1, F2, FC1, FC2, FCz, and Fz.…”

“…We equated the immediate perceptual history (from one presentation to the next) by analyzing only perceptual repetitions. Previous studies have compared presentation-to-presentation alternations with repetitions and reported modulations starting from 130 ms after stimulus onset or much later (O'Donnell et al, 1988;Kornmeier and Bach, 2004Pitts et al, 2007Pitts et al, , 2008Pitts et al, , 2009). Some reported a P120 modulation, potentially related to changes in spatial attention (Pitts et al, 2007), but none reported a modulation of the N50 peak.…”

La reconfiguración perceptual de imágenes aplicada al desarrollo del pensamiento divergente en el aula de clase

“…Si se quiere obtener una revaloración perceptual, muy posiblemente corresponda aislar los referentes conceptuales que comúnmente se relacionan con el estímulo captado, para permitirse llegar a nuevas relaciones, amparadas justamente en la reorganización perceptiva. Fundamentalmente, los procesos de arriba a abajo (bottom-up) extraen, primeramente, información sensitiva que tuvo su procedencia en el entorno físico, para luego guiar procesos perceptuales mediados por el conocimiento, las creencias, expectativas y objetivos; estos últimos remiten al esquema perceptual top-down (Smith & Kosslyn, 2008;Intaité, Noreika, Soliunas & Falter, 2013;Pitts, Gavin & Nerger, 2008). Dicho de otra manera, el procesamiento bottom-up se fundamenta en la forma básica en que los receptores sensoriales hacen registro de los estímulos; procesamientos posteriores de tipo top-down producirán impacto en la percepción, incluyendo efectos como el de reversibilidad y organización perceptual, fácilmente observables en la percepción de figuras biestables o ambiguas (Borisyuk, Chik & Kazanovich, 2009;Bruce & Green, 1994;Foley & Matlin;1996;Hsiao, Chen, Spence & Yeh, 2012;Long & Toppino, 2004;Munar, Roselló, Maiche, Travieso & Nadal, 2007;Yamamoto & Yamamoto, 2006).…”