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Selected papers. Click on a title to download a pdf.


fMRI–adaptation studies of viewpoint tuning in the extrastriate and fusiform body areas
Taylor J, Wiggett A, Downing P
J Neurophysiology (in press)

People are easily able to perceive the human body across different viewpoints, but the neural mechanisms underpinning this ability are currently unclear.  In three experiments, we used fMRI adaptation to study the view-invariance of representations in two cortical regions that have previously been shown to be sensitive to visual depictions of the human body – the extrastriate and fusiform body areas (EBA and FBA). The BOLD response to sequentially presented pairs of bodies was treated as an index of view invariance. Specifically, we compared trials in which the bodies in each image held identical poses (seen from different views) to trials containing different poses.  EBA and FBA adapted to identical views of the same pose, and both showed a progressive rebound from adaptation as a function of the angular difference between views, up to approximately 30 degrees. However, these adaptation effects were eliminated when the body stimuli were followed by a pattern mask. Delaying the mask onset increased the response (but not the adaptation effect) in EBA, leaving FBA unaffected.  We interpret these masking effects as evidence that view-dependent fMRI adaptation is driven by later waves of neuronal responses in the regions of interest. Finally, in a whole brain analysis we identified an anterior region of the left inferior temporal sulcus (l-aITS) that responded linearly to stimulus rotation, but showed no selectivity for bodies.  Our results show that body-selective cortical areas exhibit a similar degree of view-invariance as other object selective areas - such as the lateral occipitotemporal area (LO) and posterior fusiform gyrus (pFs).


Dissociation of extrastriate body- and biological-motion selective areas by manipulation of visual-motor congruency.
Kontaris J, Wiggett A, Downing P.
Neuropsychologia (2009)

To date, several posterior brain regions have been identified that play a role in the visual perception of other people and their movements. The aim of the present study is to understand how these areas may be involved in relating body movements to their visual consequences. We used fMRI to examine the extrastriate body area (EBA), the fusiform body area (FBA), and an area in the posterior superior temporal sulcus (pSTS) that responds to patterns of human biological motion. Each area was localized in individual participants with independent scans. In the main experiment, participants performed and/or viewed simple, intransitive hand actions while in the scanner. An MRcompatible camera with a near-egocentric view of the participant's hand was used to manipulate the relationship between motor output and the visual stimulus. Participants' only view of their hands was via this camera. In the Compatible condition, participants viewed their own live hand movements projected onto the screen. In the Incompatible condition, participants viewed actions that were different from the actions they were executing. In pSTS, the BOLD response in the Incompatible condition was significantly higher than in the Compatible condition. Further, the response in the Compatible condition was below baseline, and no greater than that found in a control condition in which hand actions were performed without any visual input. This indicates a strong suppression in pSTS of the response to the visual stimulus that arises from one's own actions. In contrast, in EBA and FBA, we found a large but equivalent response to the Compatible and Incompatible conditions, and this response was the same as that elicited in a control condition in which hand actions were viewed passively, with no concurrent motor task. These findings indicate that, in contrast to pSTS, EBA and FBA are decoupled from motor systems. Instead we propose that their role is limited to perceptual analysis of body-related visual input.


Animate and inanimate objects in human visual cortex: evidence for task-independent category effects.
Wiggett A, Pritchard I, Downing P.
Neuropsychologia (2009)

Evidence from neuropsychology suggests that the distinction between animate and inanimate kinds is fundamental to human cognition. Previous neuroimaging studies have reported that viewing animate objects activates ventrolateral visual brain regions, whereas inanimate objects activate ventromedial regions. However, these studies have typically compared only a small number of animate and inanimate kinds (e.g. animals and tools) and some evidence indicates that task demands determine whether these effects occur at all. In the current study we test whether a lateral-medial animacy bias is evident across a variety of stimuli, and across different tasks (matching two stimuli at a general, intermediate and exemplar level). Images of objects were presented sequentially in pairs, and match/mismatch judgements were made at different levels in different scans. The fMRI data showed ventrolateral activation for animate objects and ventromedial activation for inanimate objects. Additional analyses within these regions revealed no main effect of task, and no interactions between task and animacy. Furthermore, there were no subpopulations of voxels in any of the regions of interest that showed a significant task by animacy interaction. We conclude that ventral animate/inanimate category biases do not always depend on top-down task orientation. Furthermore, we consider whether the animate and inanimate activations reflect biases in the non-preferred responses of strongly category-selective regions such as the fusiform face area or the parahippocampal place area.


Material-independent and material-specific activation in fMRI after perceptual learning.
Mundy M, Honey R, Downing P, Wise R, Graham K, Dwyer D
Neuroreport (2009)

Schedule of exposure to similar stimuli contributes to the degree of perceptual learning over and above the amount of exposure in a variety of species and stimuli. In an event-related functional MRI study, investigating schedule and stimulus effects in perceptual learning, we found that intermixed presentation (A, B, A, B y) resulted in better subsequent discrimination than blocked presentation (C, C y D, D y) for face and checkerboard stimuli, despite being matched for the number of exposures. Exposure schedule resulted in differential activation in the same early visual regions in both types of stimuli. There was evidence of material-specific activation in the fusiform face area for faces but not for checkerboards, suggesting that material-specific mechanisms are recruited alongside more material-independent mechanisms in perceptual learning.


Three recent comment pieces:

Visual Neuroscience: A hat-trick for modularity
Downing PE
Current Biology. 2009; 19(4): R160-2.
(Comment on: "Triple dissociation of faces, bodies, and objects in extrastriate cortex,", by David Pitcher et al.)


Face Perception: Broken into parts
Downing P
Current Biology. 2007; 17(20): R888-9
(Comment on: "TMS evidence for the involvement of the right occipital face area in early face processing." by David Pitcher et al.)


The face network: overextended?
Wiggett AJ, Downing P
NeuroImage. 2008; 40(2): 420-2.
(Comment on: "Let's face it: It's a cortical network" by Alumit Ishai)





The neural basis of visual body perception
Peelen M, Downing P
Nature Reviews Neuroscience. 2007; 8(8) 636-48.

The human body, like the human face, is a rich source of socially relevant information about other individuals. Evidence from studies of both humans and non-human primates points to focal regions of the higher-level visual cortex that are specialized for the visual perception of the body. These body-selective regions, which can be dissociated from regions involved in face perception, have been implicated in the perception of the self and the 'body schema', the perception of others' emotions and the understanding of actions.


fMRI analysis of body and body part representations in the extrastriate and fusiform body areas
Taylor J, Wiggett A, Downing P
Journal of Neurophysiology. 2007; 98:1626-33.

This study examined the contributions of two previously-identified brain regions -- the extrastriate and fusiform body areas (EBA and FBA) -- to the visual representation of the human form. Specifically we measured in these two areas the magnitude of fMRI response as a function of the amount of the human figure that is visible in the image, in the range from a single finger to the entire body. A second experiment determined the selectivity of these regions for body and body part stimuli relative to closely-matched control images. We found a gradual increase in the selectivity of the EBA as a function of the amount of body shown. In contrast, the FBA shows a step like function, with no significant selectivity for individual fingers or hands. In a third experiment we demonstrate that the response pattern seen in EBA does not extend to adjacent motionselective area hMT. We propose an interpretation of these results by analogy to nearby face-selective regions OFA (occipital face area) and FFA (fusiform face area). Specifically, we hypothesize that the EBA analyzes bodies at the level of parts (as has been proposed for faces in the OFA), whereas FBA (by analogy to FFA) may have a role in processing the configuration of body parts into wholes.


Controlling for inter-stimulus perceptual variance abolishes N170 face selectivity.
Thierry G, Martin C, Downing P, Pegna A
Nature Neuroscience. 2007; 10(4): 505-11

Establishing when and how the human brain differentiates between object categories is key to understanding visual cognition. Event-related potential (ERP) investigations have led to the consensus that faces selectively elicit a negative wave peaking 170 ms after presentation, the 'N170'. In such experiments, however, faces are nearly always presented from a full front view, whereas other stimuli are more perceptually variable, leading to uncontrolled interstimulus perceptual variance (ISPV). Here, we compared ERPs elicited by faces, cars and butterflies while-for the first time-controlling ISPV (low or high). Surprisingly, the N170 was sensitive, not to object category, but to ISPV. In addition, we found category effects independent of ISPV 70 ms earlier than has been generally reported. These results demonstrate early ERP category effects in the visual domain, call into question the face selectivity of the N170 and establish ISPV as a critical factor to control in experiments relying on multitrial averaging.


Organization of felt and seen pain responses in anterior cingulate cortex.
Morrison I, Downing P
Neuroimage. 2007; 37(2): 642-51.

Previous neuroimaging studies comparing pain observation with directly-experienced pain have shown conjoint activations in the cingulate cortex between felt and seen pain. However, whereas this phenomenon may be due to the functional-anatomical overlap of a shared neural substrate, it may also reflect neighboring but distinct activations for felt and seen pain respectively, the co-localization of which is made more likely in group-averaged, spatially-smoothed data. This study explores responses to felt and seen pain, and their spatial overlap, on unsmoothed data from single subjects. Significant activation for the statistical conjunction of felt and seen pain effects was present both at the group level and in six of the eleven individual subjects. However, although each subject showed distinct felt and seen pain areas in the cingulate, a conjunction between these activations was not found in every individual. Among those that showed a felt-seen pain conjunction, its location along the gyrus was variable and the conjunction always fell in a spatially intermediate location between the felt and seen pain activations. These results suggest that the BOLD signal conjunction originates from the intersection of adjacent and partially distinct activations—which do not necessarily always overlap—rather than from a single neural population coding equally for felt and seen pain. This has implications for the interpretation of BOLD data in addressing "mirrorlike" activations in general, whether in action-related or pain-related areas.


fMRI investigation of overlapping lateral occipitotemporal activations using multi-voxel pattern analysis
Downing P, Wiggett A, Peelen M
Journal of Neuroscience. 2007; 27:226-233.

Several functional areas are proposed to reside in human lateral occipitotemporal cortex, including motion selective hMT, object-form selective LO, and body-selective EBA. Indeed several fMRI studies have reported significant activation overlap among these regions. The standard interpretation of this overlap would be that the common areas of activation reflect engagement of common neural systems. Alternatively, motion, object form, and body form may be processed independently within this general region. To distinguish these possibilities, we first analysed the lateral occipitotemporal responses to motion, objects, bodies, and body parts with whole-brain group-average analyses and within-subjects functional region of interest (ROI) analyses. The activations elicited by these stimuli, each relative to a matched control, overlapped substantially in the group analysis. When hMT, LO, and EBA were defined functionally within subjects, each ROI in each hemisphere (except right hemisphere hMT) showed significant selectivity for motion, intact objects, bodies, and body parts, even though only the peak voxel of each region was tested. In contrast, multi-voxel analyses of variations in selectivity patterns revealed that visual motion, object form, and the form of the human body elicited three relatively independent patterns of fMRI activity in lateral occipitotemporal cortex. Multi-voxel approaches, in contrast to other methods, can reveal the functional significance of overlapping fMRI activity in extrastriate cortex and, by extension, elsewhere in the brain.


The sight of others' pain modulates motor processing in human cingulate cortex
Morrison I, Peelen M, Downing P
Cerebral Cortex. 2007; 17(9):2214-22.

Neuroimaging evidence has shown that a network including cingulate cortex and bilateral insula responds to both felt and seen pain. Of these, dorsal anterior cingulate and midcingulate areas are involved in preparing context-appropriate motor responses to painful situations, but it is unclear whether the same holds for observed pain. Participants in this fMRI study viewed short animations depicting a noxious implement (eg sharp knives) or an innocuous implement (eg butter knives) striking a person's hand. Participants were required to execute or suppress button-press responses depending on whether the implements hit or missed the hand. The combination of the implement's noxiousness and whether it contacted the hand strongly affected reaction times, with the fastest responses to noxious-hit trials. BOLD signal changes mirrored this behavioral interaction with increased activation during noxious-hit trials only in midcingulate, dorsal anterior, and dorsal posterior cingulate regions. Crucially, the activation in these cingulate regions also depended on whether the subject made an overt motor response to the event, linking their role in pain observation to their role in motor processing. This study also suggests a functional topography in medial premotor regions implicated in "pain empathy", with adjacent activations relating to pain-selective and motor-selective components, and their interaction.


Using multi-voxel pattern analysis of fMRI data to interpret overlapping functional activations
Peelen M, Downing P
comment in Trends in Cognitive Sciences. 2007; 11:4-5.

Norman et al. [TICS, 2006] recently summarized the use of multi-voxel pattern analysis (MVPA) of fMRI data. They provide examples showing that patterns of activation across a set of voxels can contain far more information about mental states than the more typically-used univariate approach. Patterns of fMRI activation can be used to discriminate cognitive states (sometimes called ‘mind reading’), to relate brain activity to behavior, and to clarify the structure of neural representations. Here, we point out an additional use of MVPA: its ability to separate overlapping functional regions.


Response-specific effects of pain observation on motor behavior
Morrison I, Poliakoff E, Gordon L, Downing P
Cognition. 2007; 104(2): 407-16.

How does seeing a painful event happening to someone else influence the observer's own motor system? To address this question, we measured simple reaction times following videos showing noxious or innocuous implements contacting corporeal or noncorporeal objects. Key releases in a go/nogo task were speeded, and key presses slowed, after subjects saw a video of a needle pricking a fingertip. No such effect was seen when the observed hand was replaced by a sponge, nor when the needle was replaced by a cotton bud. These findings demonstrate that pain observation modulates the motor system by speeding withdrawal movements and slowing approach movements of the finger. This illustrates a basic mechanism by which visual information about pain is used to facilitate appropriate behavioral responses.


An event-related potential component sensitive to images of the human body
Thierry G, Pegna A, Dodds C, Roberts M, Basan S, Downing P
Neuroimage. 2006; 32:871-9.

One of the critical functions of vision is to provide information about other individuals. Neuroimaging experiments examining the cortical regions that analyze the appearance of other people have found partially overlapping networks that respond selectively to human faces and bodies. In event-related potential (ERP) studies, faces systematically elicit a negative component peaking 170 ms after presentation – the N170. To characterize the electrophysiological response to human bodies, we compared the ERPs elicited by faces, bodies, and various control stimuli. In Experiment 1, a comparison of ERPs elicited by faces, bodies, objects and places showed that pictures of the human body (without the head) elicit a negative component peaking at 190 ms (an N190). While broadly similar to the N170, the N190 differs in both spatial distribution and amplitude from the N1 components elicited by faces, objects and scenes, and peaks significantly later than the N170. The difference between N190 and N170 was further supported using topographic analyses of ERPs and source localization techniques. A unique, stable map topography was found to characterize human bodies between 130 and 230 ms. In Experiment 2, we tested the four conditions from Experiment 1, as well as intact and scrambled silhouettes and stick figures of the human body. We found that intact silhouettes and stick figures elicited significantly greater N190 amplitudes than their scrambled counterparts. Thus the N190 generalizes to some degree to schematic depictions of the human form. Overall, our findings are consistent with intertwined, but functionally distinct, neural representations of the human face and body.


Patterns of fMRI Activity Dissociate Overlapping Functional Brain Areas that Respond to Biological Motion
Peelen M, Wiggett A, Downing P
Neuron. 2006; 49, 815-822.

Accurate perception of the actions and intentions of other people is essential for successful interactions in a social environment. Several cortical areas that support this process respond selectively in fMRI to static and dynamic displays of human bodies and faces. Here we apply pattern-analysis techniques to arrive at a new understanding of the neural response to biological motion. Functionally defined body-, face-, and motion-selective visual areas all responded significantly to “point-light” human motion. Strikingly, however, only body selectivity was correlated, on a voxel-by-voxel basis, with biological motion selectivity. We conclude that (1) biological motion, through the process of structure-from-motion, engages areas involved in the analysis of the static human form; (2) body-selective regions in posterior fusiform gyrus and posterior inferior temporal sulcus overlap with, but are distinct from, face- and motion-selective regions; (3) the interpretation of region-of-interest findings may be substantially altered when multiple patterns of selectivity are considered.


The Role of the Extrastriate Body Area in Action Perception
Supplementary materials: movie 1 movie 2
Downing P, Peelen M, Wiggett A, Tew B
Social Neuroscience. 2006; 1(1), 52-62.

Numerous cortical regions respond to aspects of the human form and its actions. What is the contribution of the extrastriate body area (EBA) to this network? In particular, is the EBA involved in constructing a dynamic representation of observed actions? We scanned 16 participants with fMRI while they viewed two kinds of stimulus sequences. In the coherent condition, static frames from a movie of a single, intransitive whole-body action were presented in the correct order. In the incoherent condition, a series of frames from multiple actions (involving one actor) were presented. ROI analyses showed that the EBA, unlike area MT+ and the posterior superior temporal sulcus, responded more to the incoherent than to the coherent conditions. Whole brain analyses revealed increased activation to the coherent sequences in parietal and frontal regions that have been implicated in the observation and control of movement. We suggest that the EBA response adapts when succeeding images depict relatively similar postures (coherent condition) compared to relatively different postures (incoherent condition). We propose that the EBA plays a unique role in the perception of action, by representing the static structure, rather than dynamic aspects, of the human form.


Domain specificity in visual cortex
Supplementary materials
Downing P, Chan A, Peelen M, Dodds C, Kanwisher N
Cerebral Cortex. 2006; 16 (10), 1453-61.

We investigated the prevalence and specificity of category-selective regions in human visual cortex. In the broadest survey to date of category selectivity in visual cortex, twelve participants were scanned with fMRI while viewing scenes and 19 different object categories in a blocked design experiment. As expected, we found selectivity for faces in the fusiform face area (FFA), for scenes in the parahippocampal place area (PPA), and for bodies in the extrastriate body area (EBA). In addition, we describe three main new findings. First, evidence for the selectivity of the FFA, PPA, and EBA was strengthened by the finding that each area responded significantly more strongly to its preferred category than to the next most-effective of the remaining 19 stimulus categories tested. Second, a region in the middle temporal gyrus that has been reported to respond significantly more strongly to tools than to animals, did not respond significantly more strongly to tools than to other non-tool categories (such as fruits and vegetables), casting doubt on the characterization of this region as tool-selective. Finally, we did not find any new regions in the occipitotemporal pathway that were strongly selective for other categories. Taken together, these results demonstrate both the strong selectivity of a small number of regions, and the scarcity of such regions in visual cortex.


Is the extrastriate body area involved in motor actions?
Supp. Fig. 1 Supp. Fig. 2
Peelen, M., & Downing, P.
Nature Neuroscience. 2005, Feb; 8(2): 125.

Astafiev et al. report that unseen, visually-guided motor acts activate the extrastriate body area (EBA). This finding has potential implications for understanding the interactions between motor and perceptual systems, and suggests a mechanism by which the visual stimulation resulting from one’s own motor acts is distinguished from that produced by others. We replicated Astafiev et al.’s experiment and found, in line with their findings, action-related modulation in EBA. However, a closer look showed that the region involved in visually guided motor acts is distinct from EBA, and that action-related modulation and body-selectivity are unrelated.


Within-Subject Reproducibility of Category-Specific Visual Activation with Functional MRI
Peelen MV, Downing PE.
Hum Brain Mapp. 2005, 25:402-8

The present study used fMRI to investigate the within-subject reproducibility of activation in higher level, category-specific visual areas in order to validate the functional localization approach widely used for these areas. The brain areas we investigated included the extrastriate body area (EBA), which responds selectively to human bodies, the fusiform face area (FFA) and the occipital face area (OFA), which respond selectively to faces, and the parahippocampal place area (PPA), which responds selectively to places and scenes. All 6 subjects showed significant bilateral activation in the four areas. Reproducibility was very high for all areas both within a scanning session and between scanning sessions separated by 3 weeks. Within sessions, the mean distance between peak voxels of the same area localized by using different functional runs was 1.5 mm. The mean distance between peak voxels of areas localized in different sessions was 2.9 mm. Functional reproducibility, as expressed by the stability of T-values across sessions, was high for both within-session and between-session comparisons. We conclude that, within subjects, high-level category-specific visual areas can be localized robustly across scanning sessions.


The effect of viewpoint on body representation in the extrastriate body area.
Chan, A W-Y., Peelen, M., & Downing, P.
Neuroreport. 2004 Oct 25;15(15):2407-10.

Functional neuroimaging has revealed several brain regions that are selective for the visual appearance of others, in particular the face. More recent evidence points to a lateral temporal region that responds to the visual appearance of the human body (extrastriate body area or EBA). We tested whether this region distinguishes between egocentric and allocentric views of the self and other people. EBA activity increased significantly for allocentric relative to egocentric views in the right hemisphere, but was not influenced by identity. Whole-brain analyses revealed several regions that were infuenced by viewpoint or identity. Modulation of EBA activity by viewpoint was modest relative to modulation by stimulus class. We propose that the EBAplays a relatively early role in social vision.


Selectivity for the human body in the fusiform gyrus.
Peelen, M., and Downing, P.
Journal of Neurophysiology. 2005 Jan;93(1):603-8.

Functional neuroimaging studies have revealed human brain regions, notably in the fusiform gyrus, that respond selectively to images of faces as opposed to other kinds of objects. Here we use fMRI to show that the mid-fusiform gyrus responds with nearly the same level of selectivity to images of human bodies without faces, relative to tools and scenes. In a group-average analysis (N=22), the fusiform activations identified by contrasting faces vs. tools and bodies vs. tools are very similar. Analyses of within-subjects regions of interest, however, show that the peaks of the two activations occupy close but distinct locations. In a second experiment, we find that the body-selective fusiform region, but not the face-selective region, responds more to stick figure depictions of bodies than to scrambled controls. This result further distinguishes the two foci, and confirms that the body-selective response generalises to abstract image formats. These results challenge accounts of the mid-fusiform gyrus that focus solely on faces, and suggest that this region contains multiple distinct category-selective neural representations.


Competition in visual working memory for control of search.
Downing, PE, and Dodds, CM
Visual Cognition. 2004 Jun; 11(6): 689-703.

Recent perspectives on selective attention posit a central role for visual working memory (VWM) in the top-down control of attention. According to the biased-competition model (Desimone & Duncan, 1995), active maintenance of an object in VWM gives matching (Downing, 2000) or related (Moores, Laiti, & Chelazzi, 2003) objects in the environment a competitive advantage over other objects in gaining access to limited processing resources. Participants in this study performed a visual search task while simultaneously maintaining a second item in VWM. On half of the trials, this item appeared as a distractor item in the search array. We found no evidence that this item interferes with successful selection of the search target, as measured with response time in a target detection task and accuracy in a target discrimination task. These results are consistent with two general models: One in which a representation of the current task biases the competition between items in a unitary VWM, or one in which VWM is fractionated to allow for maintenance of critical items that are not immediately relevant to the task.


Bodies capture attention when nothing is expected.
Downing PE, Bray D, Rogers J, Childs C.
Cognition. 2004 Aug;93(1):B27-38.

Functional neuroimaging research has shown that certain classes of visual stimulus selectively activate focal regions of visual cortex. Specifically, cortical areas that generally and selectively respond to faces (Kanwisher, N., McDermott, J., & Chun, M. M. (1997). The fusiform face area: a module in human extrastriate cortex specialized for face perception. Journal of Neuroscience, 17(11), 4302-4311; Puce, A., Allison, T., Asgari, M., Gore, J. C., & McCarthy, G. (1996). Differential sensitivity of human visual cortex to faces, letterstrings, and textures: a functional magnetic resonance imaging study. Journal of Neuroscience, 16(16), 5205-5215.) and to the human body (Downing, P. E., Jiang, Y., Shuman, M., & Kanwisher, N. (2001). A cortical area selective for visual processing of the human body. Science, 293(5539), 2470-2473.) have recently been described using fMRI. A parallel body of research has focused on the ability of faces to "capture" the focus of attention, compared to other kinds of objects (Lavie, N., Ro, T., & Russell, C. (2003). The role of perceptual load in processing distractor faces. Psychological Science, 14(5), 510-515; Ro, T., Russell, C., & Lavie, N. (2001). Changing faces: a detection advantage in the flicker paradigm. Psychological Science, 12(1), 94-99; Vuilleumier, P. (2000). Faces call for attention: evidence from patients with visual extinction. Neuropsychologia, 38(5), 693-700.). The present study uses Mack and Rock's "inattentional blindness" paradigm to investigate whether unexpected, task-irrelevant human body stimuli capture awareness when attention is occupied by a primary task (Mack, A., & Rock, I. (1998). Inattentional blindness. London: MIT Press). Silhouettes and stick figures of human bodies, and silhouettes of hands, were compared to control stimuli including object silhouettes, object stick figures, and scrambled silhouettes of bodies, body parts, and objects. Participants were significantly better able to detect a human figure relative to the control stimuli. These results suggest that the human body, like the face, may be prioritized for attentional selection. More generally, they are consistent with the proposal that the visual system assigns attentional priority to types of stimuli that are also represented in strongly selective cortical regions.


Why does the gaze of others direct visual attention?
Downing PE, Dodds CM, Bray D.
Visual Cognition. 2004 11(1):71-79.

Viewing another person directing his or her gaze can produce automatic shifts of covert visual attention in the same direction. This holds true even when the task-relevant target is much more likely to occur at the uncued location. These findings, along with other evidence, have been taken to suggest that gaze represents a “special” stimulus – the foundation of a social cognition system that can make inferences about the mental states of other people. However, gaze-driven cueing effects could simply be due to spatial compatibility between cue and target. We compared the attentional effects of gaze shifts to a face with the tongue extended laterally to the left or right. When tongue direction was a non-predictive cue, we found cueing effects from tongues that were indistinguishable from those produced by gaze. However, in contrast to previous findings with gaze, tongue cues did not overcome a validity manipulation in which targets were 4 times more likely to appear at the uncued location. We conclude that simple attentional cueing effects from gaze may be better explained by spatial compatibility, and that more complex, unique features of cueing from gaze may be better indices into perceptual systems specialised for social cognition.


Viewpoint-specific scene representations in human parahippocampal cortex.
Epstein R, Graham KS, Downing PE.
Neuron. 2003 Mar 6;37(5):865-76.

The "parahippocampal place area" (PPA) responds more strongly in functional magnetic resonance imaging (fMRI) to scenes than to faces, objects, or other visual stimuli. We used an event-related fMRI adaptation paradigm to test whether the PPA represents scenes in a viewpoint-specific or viewpoint-invariant manner. The PPA responded just as strongly to viewpoint changes that preserved intrinsic scene geometry as it did to complete scene changes, but less strongly to object changes within the scene. In contrast, lateral occipital cortex responded more strongly to object changes than to spatial changes. These results demonstrate that scene processing in the PPA is viewpoint specific and suggest that the PPA represents the relationship between the observer and the surfaces that define local space.


A cortical area selective for visual processing of the human body.
Downing PE, Jiang Y, Shuman M, Kanwisher N.
Science. 2001 Sep 28;293(5539):2470-3.

Despite extensive evidence for regions of human visual cortex that respond selectively to faces, few studies have considered the cortical representation of the appearance of the rest of the human body. We present a series of functional magnetic resonance imaging (fMRI) studies revealing substantial evidence for a distinct cortical region in humans that responds selectively to images of the human body, as compared with a wide range of control stimuli. This region was found in the lateral occipitotemporal cortex in all subjects tested and apparently reflects a specialized neural system for the visual perception of the human body.


Testing cognitive models of visual attention with fMRI and MEG.
Downing P, Liu J, Kanwisher N.
Neuropsychologia. 2001;39(12):1329-42.

Neuroimaging techniques can be used not only to identify the neural substrates of attention, but also to test cognitive theories of attention. Here we consider four classic questions in the psychology of visual attention: (i) Are some 'special' classes of stimuli (e.g. faces) immune to attentional modulation?; (ii) What are the information units on which attention operates?; (iii) How early in stimulus processing are attentional effects observed?; and (iv) Are common mechanisms involved in different modes of attentional selection (e.g. spatial and non-spatial selection)? We describe studies from our laboratory that illustrate the ways in which fMRI and MEG can provide key evidence in answering these questions. A central methodological theme in many of our fMRI studies is the use of analyses in which the activity in certain functionally-defined regions of interest (ROIs) is used to test specific cognitive hypotheses. An analogous sensor-of-interest (SOI) approach is applied to MEG. Our results include: evidence for the modulation of face representations by attention; confirmation of the independent contributions of object-based and location-based selection; evidence for modulation of face representations by non-spatial selection within the first 170 ms of processing; and implication of the intraparietal sulcus in functions general to spatial and non-spatial visual selection.


Interactions between visual working memory and selective attention.
Downing PE.
Psychol Sci. 2000 Nov;11(6):467-73.

The relationship between working memory and selective attention has traditionally been discussed as operating in one direction: Attention filters incoming information, allowing only relevant information into short-term processing stores. This study tested the prediction that the contents of visual working memory also influence the guidance of selective attention. Participants held a sample object in working memory on each trial. Two objects, one matching the sample and the other novel, were then presented simultaneously. As measured by a probe task, attention shifted to the object matching the sample. This effect generalized across object type, attentional-probe task, and working memory task. In contrast, a matched task with no memory requirement showed the opposite pattern, demonstrating that this effect is not simply due to exposure to the sample. These results confirm a specific prediction about the influence of working memory contents on the guidance of attention.


fMRI evidence for objects as the units of attentional selection.
O'Craven KM, Downing PE, Kanwisher N.
Nature. 1999 Oct 7;401(6753):584-7.

Contrasting theories of visual attention emphasize selection by spatial location, visual features (such as motion or colour) or whole objects. Here we used functional magnetic resonance imaging (fMRI) to test key predictions of the object-based theory, which proposes that pre-attentive mechanisms segment the visual array into discrete objects, groups, or surfaces, which serve as targets for visual attention. Subjects viewed stimuli consisting of a face transparently superimposed on a house, with one moving and the other stationary. In different conditions, subjects attended to the face, the house or the motion. The magnetic resonance signal from each subject's fusiform face area, parahippocampal place area and area MT/MST provided a measure of the processing of faces, houses and visual motion, respectively. Although all three attributes occupied the same location, attending to one attribute of an object (such as the motion of a moving face) enhanced the neural representation not only of that attribute but also of the other attribute of the same object (for example, the face), compared with attributes of the other object (for example, the house). These results cannot be explained by models in which attention selects locations or features, and provide physiological evidence that whole objects are selected even when only one visual attribute is relevant.


The line-motion illusion: attention or impletion?
Downing PE, Treisman AM.
J Exp Psychol Hum Percept Perform. 1997 Jun;23(3):768-79.

When a brief lateral cue precedes an instantaneously presented horizontal line, observers report a sensation of motion in the line propagating from the cued end toward the uncued end. This illusion has been described as a measure of the facilitatory effects of a visual attention gradient (O. Hikosaka, S. Miyauchi, & S. Shimojo, 1993a). Evidence in the present study favors, instead, an account in which the illusion is the result of an impletion process that fills in interpolated events after the cue and the line are linked as successive states of a single object in apparent motion.