ABSTRACT
Cognition is involved in almost any aspect of visual perception; there is multiple involvement of cognitive capacities such as attention (working) memory and planning in the detection, discrimination, identification and recognition of visual stimuli, and in the visual-executive guidance of oculomotor and also visually guided social activities (Farah, 2000). Visual identification and visual recognition particularly require cognition but they are also based on more elementary visual functions and capacities such as the visual field, visual acuity and form vision, contrast sensitivity, colour vision, and-as outlined in Chapter 6-also the field of attention. It is well known that functional properties of the extrastriate regions in the ventral visual pathway are involved in the perception and representation of objects and faces (Grill-Spector, 2003). Top-down processes guided by the prefrontal cortex facilitate visual object recognition (Bar, 2003). There exists empirical evidence for category-specific processing of visual stimuli in humans (Ishai et al., 1999; Sigala, 2004; Wierenga et al., 2009). Yet, the main question remains: how does the brain eventually compute and code visual objects for accurate identification and recognition? Intermediate cortical stages selectively process objects in a viewpoint-and size-dependent manner, while higher order areas in lateral occipital and posterior parietal cortex are involved in object processing independent of image transformation. Thus, visual object information is similarly coded and
represented in two parallel and hierarchically organised processing systems in the ventral and dorsal visual pathways (Konen & Kastner, 2008).
