‘What’ and ‘where’ in the human brain

“Two broad pathways with fairly distinct anatomical organization and functional properties are generally referred to as the ventral and dorsal visual streams (Macko et al., 1982; Ungerleider and Mishkin, 1982; Ungerleider and Haxby, 1994).”

“Activation of the ITG and prefrontal areas (BA10) are also consistent with previous studies that found these areas to be implicated in semantic processing, object recognition, and working memory, respectively.(22,34,46,50,53,54) Examination of the mean asymmetry indices per region showed all regions to be lateralized…”

“The ventral cortical pathway, in our model (V1-color →V2/4- color→IT), contained neuronal units in successive areas having progressively larger receptive fields until, in inferotemporal cortex (IT), receptive fields cover nearly the entire visual field (Ungerleider and Haxby, 1994).”

“Key brain regions associated with bottom- up attention include the insula, anterior cingulate cortex, and dorsolateral prefrontal cortex (Felleman & Van Essen, 1991; Ungerleider & Haxby, 1994).”

“The effects of brain lesions on eye movements may be influenced by the ‘‘confounding influence of compensatory responses to brain injury” (Ungerleider & Haxby, 1994).”

“…portions of the ventral visual processing stream — the left temporal--occipital junction and the left posterior temporal lobe, as well as the left inferior parietal region of the dorsal visual processing stream (Ungerleider and Mishkin, 1982; Ungerleider and Haxby, 1994; Yantis and Serences, 2003).”

“levels of the human visual system (Ungerleider and Haxby, 1994).”

“These higher order visual association areas are generally divided into 2 interlinked streams: (1) the ventral stream for the recognition of objects, colours and people, which extends to the inferior temporal cortex; (2) the dorsal stream for motion and overview vision [”

“DOT regions have also been suggested to be part of a “where is it” pathway for object recognition [Hasson et al., 2002; Ungerleider and Haxby, 1994 ].”

“…occipitotemporal pathway is responsible for processing object information, and a dorsal occipitoparietal pathway has been demonstrated for spatial information, both pathways eventually converging upon the MTL (e.g., Ungerleider and Mishkin, 1982; Ungerleider and Haxby, 1994; Köhler et al., 1998b).”

“…Mishkin, 1982 ), leading to the popular, but highly schematic, two visual systems theory ( Milner and Goodale, 2008; Ungerlei-der and Mishkin, 1982; Ungerleider and Haxby, 1994 ), in which a dorsal stream is specialised in motion perception and the analysis of the spatial structure of the visual…”

“A variety of neuropsychological, neurophysiological, and neuroimaging data in humans and animals identify this region as part of the ventral visual pathway used in the processing of visual stimuli as objects (Ungerleider and Mishkin, 1982; Ungerleider and Haxby, 1994; Farah, 1995).”

“PRc receives the majority of its input from temporal lobe structures in the ''ventral visual stream'' known to be critical for object recognition (Mishkin et al., 1983: Ungerleider and Haxby, 1994).”

“Briefly, in this conception, the ventral visual stream processes information specific to the identity of the object, whereas the dorsal stream processes location information (Mishkin and Ungerleider 1982; Ungerleider and Haxby 1994; Ungerleider et al. 1998).”

“In contrast, the dorsal occipital and superior parietal cortex are more preferentially engaged during visual-spatial tasks (Milner and Goodale 2008; Ungerleider et al. 1998; Ungerleider and Haxby 1994).”

“These are often referred to as the ‘what’ and ‘where’ visual pathways, as the former appears to represent stimulus identity, while the latter represents stimulus location (Ungerleider and Haxby, 1994).”

“Conscious allocentricity may be related to the distinction between ventral and dorsal visual pathways (Ungerleider & Haxby 1994).”

“These regions are known to be part of the ventral visual pathway (Ungerleider and Haxby, 1994; Boussaoud et al., 1995; Haxby et al., 1991).”

“that due to the limited processing capacity of the brain presen-tationofmultiplestimulileadstosensorysuppressive interactions,whichalterthereceptivefieldsizeofneu-ronsintheextrastriatecortexbyeitherbottom-upor Existingliteraturehasindicatedtheroleofthefron-toparietalnetworkforsustainedattention,whereas brainregionsinbo…”

“These activations comprise the dorsal and ventral visual stream (Mishkin et al., 1983; Ungerleider and Haxby, 1994) and include the frontal eye fields (Corbetta et al., 2002).”

“…stream (represented by Server 2) and the magnocellular stream (Server 3)—where the object content features (e.g., color, shape, labeling, etc.) and location features (e.g., spatial coordinates, speed, etc.) are processed (Bear, et al., 2001; Smith & Jonides, 1998; Ungerleider & Haxby, 1994).”

“These findings highlight disruptions in discrete, task-dependent networks that may contribute to the ASD phenotype (Caspers et al., 2014; Mishkin and Ungerleider, 1982; Nickl-Jockschat et al., 2014; Ungerleider and Haxby, 1994).”

“Strong interconnectivity has been often described between areas belonging to the same functional system, such as the dorsal or ventral streams in vision [Ungerleider and Haxby, 1994].”

“Area V4, as part of the ventral processing stream (Ungerleider & Haxby, 1994), is understood as an intermediate stage in the synthesis of complex visual objects.”

“There are two reasons that the color information is removed in temporal stream network: 1) in human visual system, color information and motion information are processed in ventral stream and dorsal stream separately [19], [59].”

“The Group 1 regions are thus especially related to ventral stream “what” processing (Ungerleider & Haxby, 1994), and allow many widely separated brain regions at the top of processing streams to provide “what,” “when,” and reward inputs to the hippocampal system.”

“This division of attributes is consistent with the distinction between pathways for “what” and “where” (Mishkin et al. 1983; Ungerleider and Haxby 1994).”

“Within the primate visual system, the ventral stream [Mishkin et al., 1983; Ungerleider and Haxby, 1994] is particularly involved in the recognition and identification of objects.”

“In this study we focus on the motor aspects of the dorsal stream, but it is worth noting that this circuit is also involved in visuospatial perception (e.g., Ungerleider and Haxby 1994).”

“In the visual cortex, spatial and non-spatial stimulus properties are, to a large degree, processed by separate functional streams (Ungerleider and Haxby, 1994).”

“Ungerleider, L. G., & Mishkin, M. (1982).”

“The two streams are implemented bilaterally and were similarly found in humans (Goodale and Milner, 1992; Ungerleider and Haxby, 1994).”

“The visual processing system is known to contain two parallel streams of processing, i.e., ventral and dorsal streams, to process object and spatial vision, respectively (Ungerleider and Haxby, 1994).”

“These are the ventral (what) and the dorsal (where) pathways (Ungerleider and Haxby, 1994).”

“It has been proposed that the auditory system is also organized into two domain-dependent, spatial and nonspatial, processing streams, similar to that seen in the visual system (Ungerleider and Haxby, 1994; Ungerleider and Mishkin, 1982).”

“The finding that these more ventral objectsensitive areas were not recruited for mental rotation, except for a small part of object-sensitive VOT-CoS, is consistent with the classic dorsal–ventral, where–what dichotomy (Ungerleider and Haxby, 1994).”

“Written words and faces are highly important visual stimuli that are processed through occipital (visual), unimodal, and heteromodal temporal association cortices and paralimbic and limbic structures (Goodale and Milner 1992; Ungerleider and Haxby 1994; Mesulam 1998).”

“This network may also include visual cortical regions, depending upon the stimuli and task (e.g., Corbetta, Miezen, Dobmeyer, Shulman, & Petersen, 1990), in line with the distinction between ventral and dorsal visual pathways (Ungerleider & Mishkin, 1982; Ungerleider & Haxby, 1994 ).”

“…cluster, the minimal p value inside the cluster, the MNI coordinates of the voxel with minimal p value, and the location of the cluster (estimated from the Harvard–Oxford Cortical and Subcortical Structural Atlases and the Cerebellar Atlas in FSL). object recognition (Ungerleider and Haxby, 1994).”

“According to Ungerleider (Ungerleider and Haxby, 1994; Ungerleider et al., 1998), the so-called ventral and dorsal stream are involved in processing visuo-spatial information.”

“It has been proposed that visual field maps can be grouped into a dorsal and a ventral stream (Ungerleider and Mishkin, 1982; Ungerleider and Haxby, 1994; Milner and Goodale, 1995).”

“This extended magnocellular-dominated dorsal stream is critical primarily for detecting spatial relationships as well as rapid changes, hence enabling sensitivity to motion (Ungerleider and Haxby, 1994), and is considered important for intact reading (Stein and Walsh, 1997).”

“…is consistent with the hypothesis that ventral visual cortex is largely specialized for recognition processes that depend heavily on foveal and parafoveal vision (Ungerleider & Mishkin, 1982 ; Goodale & Milner, 1992 ; Ungerleider & Haxby, 1994 ; Levy et al., 2001 ; Malach et al., 2002 ).”

“1982), involved in the recognition of faces and objects (Goodale and Milner 1992; Ungerleider and Haxby 1994) as well as the encoding of spatial relationships between the subparts of scenes, potentially for manipulation (Rottschy et al.”

“It is assumed that visual objects have different representations in ventral stream and dorsal stream ( Ungerleider & Haxby, 1994; Ungerleider & Mishkin, 1982).”

“Although both face and complex object perception use the ventral pathway, faces are perceived, at least in part, by a separate processing stream in the ventral pathway.(73) Based on converging evidence from EEG(74) and MEG,(75) the fusiform gyrus (FG) is considered to be one of the main neural sources of the N170 in r…”

“Neuroimaging studies support the formulation that spatial processing chiefly involves dorsal stream—occipitoparietal pathway , whereas object processing tend to involve ventral, occipitotemporal pathway (Ungerleider and Mishkin, 1982, Ungerleider and Haxby, 1994).”

“Such segregation is reminiscent of the “what” and “where” processing streams in the visual system (reviewed in, e.g., Ungerleider and Haxby 1994) that have also been proposed for the auditory system (Rauschecker and Tian 2000).”

“These results are consistent with previous reports that in both humans and monkeys, the dorsal visual pathways process information related to object location and the ventral pathways process information related to object identity [25,45,73,74,80].”

“The occipito-temporal network is important for central vision and the generation of small saccades, and the occipito- parietal network for spatial global vision and the generation of long saccades (Ungerleider and Haxby, 1994; Bullier et al., 1996).”

“…medial/lateral entorhinal cortex; spatial/nonspatial information; dopamine; norepinephrine INTRODUCTION The brain has the capacity for parallel information processing, in which sensory information received from the environment is segregated and independently processed based on particular features.”

“…al., 1995; Tresch, Sinnamon, & Seamon, 1993) originated with the proposal that the neuroanatomicaland neurophysiological organizational principles of the primate visual system (Ungerleider & Haxby, 1994; Ungerleider & Mishkin,1982) might extend to visual working memory (Goldman-Rakic, 1987, 1990).”

“…changes in item identity and position are processed in a similar fashion even though different neuronal systems are involved in object recognition and localization (Ungerleider & Haxby, 1994), we recorded event-related brain potentials (ERPs) during visual search in a change blindness paradigm.”

“This seems particularly germane because it is claimed that the human homologue of several key areas of the ventral and dorsal systems have yet to be identified or clearly specified (Eidelberg & Galaburda, 1984; Ungerleider & Haxby, 1994; see also Courtney et al., 1996).”

“Many complex CRF characteristics that have been reported at higher levels appear to be absent or less prevalent at lower levels of the anatomical hierarchy (Felleman and Van Essen 1991; Ungerleider and Haxby 1994; Van Essen and Gallant 1994).”

“More cortical tissue is given to visual and spatial processing than to any of the other sensory modalities (see Felleman & Van Essen, 1991; Ungerleider & Haxby, 1994).”

“Hierarchical organization aside, the processing of the visual stimuli following V1 has also been found to diverge into two main pathways or streams (Ungerleider and Haxby, 1994; Mishkin et al, 1983), see Figure 1.”

“…streams support different aspects of perception has been established as a framework for understanding perception for visual and auditory perception (Ungerleider and Haxby, 1994; Rauschecker and Tian, 2000), and is also becoming a widely accepted view for speech processing (e.g., Hickok and…”