Neuroimaging evidence for object model verification theory: Role of prefrontal control in visual object categorization

Abstract

Although the visual system rapidly categorizes objects seen under optimal viewing conditions, the categorization of objects seen under impoverished viewing conditions not only requires more time but also may depend more on top-down processing, as hypothesized by object model verification theory. Two studies, one with functional magnetic resonance imaging (fMRI) and one behavioral with the same stimuli, tested this hypothesis. FMRI data were acquired while people categorized more impoverished (MI) and less impoverished (LI) line drawings of objects. FMRI results revealed stronger activation during the MI than LI condition in brain regions involved in top-down control (inferior and medial prefrontal cortex, intraparietal sulcus), and in posterior, object-sensitive, brain regions (ventral and dorsal occipitotemporal, and occipitoparietal cortex). The behavioral study indicated that taxing visuospatial working memory, a key component of top-down control processes during visual tasks, interferes more with the categorization of MI stimuli (but not LI stimuli) than does taxing verbal working memory. Together, these findings provide evidence for object model verification theory and implicate greater prefrontal cortex involvement in top-down control of posterior visual processes during the categorization of more impoverished images of objects.

[P3–382]: NEURAL EVIDENCE FOR DEFECTIVE TOP‐DOWN CONTROL OF VISUAL PROCESSING IN PARKINSON's AND ALZHEIMER's DISEASE

“…2 and summarized in Tables S5a-d in Supplementary material. Consistent with previous functional imaging studies (Ganis et al, 2007;Kosslyn et al, 1994;Schendan and Stem, 2007;Schendan and Stern, 2008), an unconventional views effect in HC was observed in object-sensitive visual areas within the ventral (temporo-occipital) and dorsal (occipito-parietal) pathways and in frontoparietal areas implicated in selective attention, working memory, and executive control including anterior cingulate cortex (ACC), anterior insula, inferior frontal gyrus (IFG), middle frontal gyrus (MFG), and superior and inferior parietal lobules (SPL, IPL, respectively) (Fedorenko et al, 2013;Niendam et al, 2012;Spreng et al, 2010;Vincent et al, 2008). Similar brain regions were engaged in the PD-NC group (though the clusters were smaller in size), see Fig.…”

“…In our HC subjects the fMRI contrast of unconventional vs. conventional views tasks demonstrated increased recruitment of both domain-specific temporal-occipital/ventral pathway and occipito-parietal/dorsal pathway visual areas, as well as the engagement of domain-general frontoparietal regions implicated in top-down control of visual processing. These results are consistent with the notion that recognizing objects under impoverished or unfamiliar viewing conditions requires the engagement of an "object model verification process" (OMVP) (Ganis et al, 2007;Kosslyn et al, 1994;Schendan and Stem, 2007;Schendan and Stern, 2008). According to OMVP theory, the greater task difficulty associated with identifying objects from unconventional views is expected to produce increased activation of both domain-general frontoparietal networks involved in selective attention, working memory, and executive control (Ganis et al, 2007;Kosslyn et al, 1994;Lowe, 2000) and domain-specific regions within the dorsal and ventral visual pathways.…”

“…These results are consistent with the notion that recognizing objects under impoverished or unfamiliar viewing conditions requires the engagement of an "object model verification process" (OMVP) (Ganis et al, 2007;Kosslyn et al, 1994;Schendan and Stem, 2007;Schendan and Stern, 2008). According to OMVP theory, the greater task difficulty associated with identifying objects from unconventional views is expected to produce increased activation of both domain-general frontoparietal networks involved in selective attention, working memory, and executive control (Ganis et al, 2007;Kosslyn et al, 1994;Lowe, 2000) and domain-specific regions within the dorsal and ventral visual pathways. The enhanced recruitment of domain-specific regions occurs because the cognitive operations required for identifying objects presented in unconventional views are likely to involve mental rotation mediated by the dorsal pathway (Ganis et al, 2007;Kosslyn et al, 1994;Schendan and Stem, 2007;Schendan and Stern, 2008), as well as extensive search for stored memory representations of objects within the ventral pathway that provide the best match for the visual input.…”

“…Similarly, some fMRI studies in normal subjects have reported selective activation of the ventral vs. dorsal pathways when objects were presented in conventional vs. unconventional orientations (Valyear et al, 2006). By contrast, a number of imaging studies have reported the engagement of both ventral and dorsal pathways during object identity and orientation judgments (Altmann et al, 2005;Ganis et al, 2007;Grill-Spector et al, 2001;Schendan and Stem, 2007;Schendan and Stern, 2008). It has also been shown that, in addition to bottom-up processing of visual information by the ventral and dorsal pathways, presenting objects in unconventional orientations engages frontoparietal cortical networks implicated in top-down attention and executive control functions (Ganis et al, 2007;Kosslyn et al, 1994;Schendan and Stem, 2007;Schendan and Stern, 2008).…”

Neurophysiological Evidence for the Time Course of Activation of Global Shape, Part, and Local Contour Representations during Visual Object Categorization and Memory

“…Later during the N350, this occipito-temporal cortex is active again, but this time performing the higher-order neural computations, involving recurrent and feedback interactions within these areas and with other areas, such as ventrolateral prefrontal cortex (Brincat & Connor, 2006;David, Harrison, & Friston, 2005), that support more sophisticated cognitive abilities with objects (Kosslyn et al, 1994), as well as implicit object memory (Schendan & Kutas, 2003) and perhaps familiarity (Curran et al, 2002). This state enables activation of the detailed visual knowledge required for the object model selection or model verification processes involved in abilities, such as basic level categorization of an object into a known class (e.g., dog, car, cup) or identification of individual objects like your cat or his bat (Ganis, Schendan, & Kosslyn, 2007;Lowe, 2000). This second state of interactive activity also supports phenomenological awareness of this knowledge.…”