Correspondence effects for objects with opposing left and right protrusions

Choice reactions to a property of an object stimulus are often faster when the location of a graspable part of the object corresponds with the location of a keypress response than when it does not, a phenomenon called the object-based Simon effect. Experiments 1-3 examined this effect for variants of teapot stimuli that were oriented to the left or right. Whether keypress responses were made with fingers within the same hand or between different hands was also manipulated. Experiment 1 showed that, for judgments of stimulus color and upright-inverted orientation, the Simon effect for intact teapots occurred in the direction of the spout location and was larger for within- than between-hand response modes. In Experiments 2 and 3, teapots with the handle or spout removed showed separate contributions of each component to the Simon effect. In Experiment 4, we clarified a discrepancy between our findings of object-based Simon effects and a previously reported absence of effect with color judgments for door-handle stimuli. We obtained an object-based Simon effect with respect to handle position when the bases of the door handles were centered but not when the handles were centered. The findings that object-based Simon effects occur with color judgments and when responses are fingers on the same hand are in closer agreement with a location coding account than with a grasping affordance account.     

The role of attention in the affordance effect: can we afford to ignore it?

It has been established that the task-irrelevant orientation of an object's graspable handle produces a stimulus-response compatibility effect, resulting in faster reaction times when the location of the response corresponds to that of the object's handle. There is ongoing debate whether to attribute this affordance effect to motoric or to attentional components. In an attempt to reconcile these two viewpoints, we employed a novel experimental approach for investigating the relationship between attention and affordance. Using 3-D positional sound, auditory spatial attention was manipulated in order to explore its effects on affordance. Subjects were presented images of everyday graspable objects and had to respond bimanually (left or right) whether the object (featuring a leftward or rightward handle) was presented upright or upside-down. Prior to each affording object, sound localization cues were manipulated so as to orient auditory attention to the left, or to the right of the interaural axis (control). We obtained a peculiar pattern of results, which not only appears to provide support for an attention-shift account of affordance but does so in a cross-modal context.     

Object-based correspondence effects for action-relevant and surface-property judgments with keypress responses: evidence for a basis in spatial coding

It has been proposed that grasping affordances produce a Simon-type correspondence effect for left–right keypress responses and the location of the graspable part of an object for judgments based on action-relevant properties such as shape, but not on surface properties. We tested the implications of this grasping affordance account and contrasted them with the ones derived from a spatial coding account that distinguishes holistic processing of integral dimensions and analytic processing of separable dimensions. In Experiments 1–3, judgments about the color of a door handle showed a Simon effect relative to the handle’s base, whereas judgments about the handle’s shape showed no Simon effect. In Experiment 4, when the middle of the handle was colored, the Simon effect was obtained relative to the base, but when the color was at the tip of the handle or near the base, Simon effects were obtained relative to the color location. For Experiment 5, only the base was colored, and the Simon effect was larger for a passive rather than active handle state, as in the color-judgment conditions of Experiments 2–4 in which the colored region overlapped with the base. In Experiment 6, orientation judgments showed no Simon effect, as the shape judgments did in Experiments 1 and 2. The findings of (a) an absence of Simon effects for shape and orientation judgments, (b) no larger Simon effects for active than passive handle states, and (c) isolation of the changing component for color judgments are consistent with the spatial coding account, according to which the distinction between object shape/orientation and color is one of integral versus separable dimensions.     

The role of attention in the occurrence of the affordance effect

It has been demonstrated that visual objects activate responses spatially corresponding to the orientation (left or right) of their graspable parts. To investigate the role of attention orienting in the generation of this effect, which we will refer to as affordance effect, we ran three experiments in which the target stimulus could either correspond or not with a dynamic event capturing attention. Participants were required to press a left or right key according to the vertical orientation (upward or inverted) of objects presented with their handles oriented to the right or to the left. In Experiments 1 and 2, the objects were located above or below fixation, while in Experiment 3, to assess the contemporary presence of the affordance and Simon effects, the objects were located to the left or right of fixation. The results showed that while the affordance effect, when evident, was always relative to the target object, irrespective of its attentional capturing properties, the Simon effect occurred relative to the event capturing attention. These findings suggest that automatic and controlled processes of visual attention may play a differential role in the occurrence of the two effects.     

Searching for Memory Systems

The aim of the present study was to investigate the relationship between the affordance effect (i.e., the advantage for responses corresponding spatially with the location of an object's graspable part) and the Simon effect (i.e., the advantage for responses corresponding spatially with stimulus location) and to assess whether they both occur at the response selection stage. In two experiments participants were required to respond according to the vertical orientation (upward or inverted) of photographs of graspable objects, located to the left or right of fixation, with their handles oriented to the right or left. In Experiment 1 the response was a buttonpress; in Experiment 2 was a reaching movement. Our results showed that both Simon and affordance effects emerged in response times but not in movement times. In Experiment 1, the two effects did not interact, whereas a clear interaction emerged in Experiment 2. These results seem to suggest that the interaction between Simon and affordance effects may depend on the type of required action.     

基于客体的一致性效应的产生机制

采用具有不同深度信息的剪影和图片刺激为材料,要求被试完成形状判断任务,探究基于客体的一致性效应的产生机制。实验1中客体刺激呈现于屏幕中央位置;实验2进一步增强了刺激空间呈现的左右位置倾向;实验3则通过交叉手的范式分离了反应位置和反应手不同的编码对一致性效应的作用。结果发现:当刺激不存在显著的左右位置信息时,剪影刺激出现了一致性效应,图片则没有;而当刺激的空间位置信息显著时,剪影和图片均出现了一致性效应,这一效应在反应位置和反应手编码分离后仍然存在。因此得出结论:空间位置编码假说对解释基于客体的一致性效应的产生有重要作用。     

Conceptual and physical object qualities contribute differently to motor affordances

Priming studies have demonstrated that an object’s intrinsic and extrinsic qualities (size, orientation) influence subsequent motor behavior thus suggesting that these object qualities ‘afford’ actions that are congruent with the prime. We present four experiments that aim to evaluate the relative effect of conceptual and physical object qualities on action priming. In Experiment 1 equally graspable known and unknown tools are presented as primes. In Experiment 2 the primes depict high versus low graspable unfamiliar tools, and in Experiments 3 and 4 we present simple graspable shapes versus high graspable unfamiliar or familiar tools respectively. In all experiments the (unrelated) task consists of a timed motor response to the direction of a centrally placed arrow that is superimposed on the prime. Whereas tool familiarity reveals no significant difference on reaction time (Exp 1), responses to high graspable unfamiliar tools (Exp 2) and simple graspable shapes (Exps 3 and 4) are significantly faster. We conclude that motor affordances are most readily determined by object qualities that depend on the object’s physical appearance provided by visual information. Conceptual information about the stimuli, such as semantic category or stored knowledge about its function and associated movements, does not appear to produce detectable effects of action priming in this paradigm.     

Motor inhibition associated with the affordance of briefly displayed objects

Research has demonstrated that left- and right-hand responses are facilitated when they are performed with the hand compatible with the orientation of a viewed object. This suggests that graspable objects automatically activate the motor representations that correspond to their orientation. It has recently been proposed that similar positive stimulus–response compatibility effects (PCE) may turn into negative compatibility effects (NCE) when a prime object is displayed very briefly. These NCEs are suggested to reflect motor inhibition mechanisms—motor activation triggered by briefly viewed objects may be treated by the motor system as unwanted, and thus it is rapidly inhibited. We examined whether the motor activation triggered by the orientation of a task-irrelevant object is similarly inhibited when the object is displayed briefly. In Experiment 1, a NCE was observed between the orientation of an object and the responding hand when the object was displayed for 30 or 70 ms. The effect turned into a PCE when the object was displayed for 370 ms. Experiment 2 confirmed that this motor inhibition effect was produced by the handle affordance of the object rather than some abstract visual properties of the object.     

Simon-like and functional affordance effects with tools: The effects of object perceptual discrimination and object action state

In the present study two separate stimulus–response compatibility effects (functional affordance and Simon-like effects) were investigated with centrally presented pictures of an object tool (a torch) characterized by a structural separation between the graspable portion and the goal-directed portion. In Experiment 1, participants were required to decide whether the torch was red or blue, while in Experiment 2 they were required to decide whether the torch was upright or inverted. Our results showed that with the same stimulus two types of compatibility effect emerged: one based on the direction signalled by the goal-directed portion of the tool (a Simon-like effect as observed in Experiment 1), and the other based on the actions associated with an object (a functional affordance effect as observed in Experiment 2). Both effects emerged independently of the person's intention to act on the stimulus, but depended on the stimulus properties that were processed in order to perform the task.     

When left feels right: asymmetry in the affordance effect

Previous research has demonstrated the existence of the so-called affordance effect (faster response when the visual affordance of a graspable object (e.g., a pan) corresponds to the response location). It has been argued that the effect is due to abstract spatial coding of the position of the handle relative to the object instead of the grasping affordance. Our experiment tested the hypothesis that the affordance effect is not caused solely by abstract spatial coding but also by specific motor activation in response to the visual affordance. We assumed that, in the case of abstract spatial codes, response location and not hand distinction would be the critical factor for producing an affordance effect. In our experiment, bi-manual crossed/uncrossed responses to left/right symbols superimposed on a picture of a pan were used. The task was to attend to the symbol and to press a corresponding left/right button. Affordances of the pan were manipulated. A three-way interaction between side of affordance (left/right), mode of response (crossed/uncrossed hands), and response-affordance correspondence (corresponding/non-corresponding) showed a correspondence effect in the right affordance condition with hands uncrossed and no correspondence effect with hands crossed. The correspondence effect was obtained in the left affordance condition across hand positions that differed only by their magnitude. Overall, the results suggest that both mechanisms (grasping affordance and spatial codes) differentially contribute to the processing of an object with a graspable handle, depending on the affordance side and response hand.     

Motor inhibition associated with the affordance of briefly displayed objects

Research has demonstrated that left- and right-hand responses are facilitated when they are performed with the hand compatible with the orientation of a viewed object. This suggests that graspable objects automatically activate the motor representations that correspond to their orientation. It has recently been proposed that similar positive stimulus-response compatibility effects (PCE) may turn into negative compatibility effects (NCE) when a prime object is displayed very briefly. These NCEs are suggested to reflect motor inhibition mechanisms--motor activation triggered by briefly viewed objects may be treated by the motor system as unwanted, and thus it is rapidly inhibited. We examined whether the motor activation triggered by the orientation of a task-irrelevant object is similarly inhibited when the object is displayed briefly. In Experiment 1, a NCE was observed between the orientation of an object and the responding hand when the object was displayed for 30 or 70 ms. The effect turned into a PCE when the object was displayed for 370 ms. Experiment 2 confirmed that this motor inhibition effect was produced by the handle affordance of the object rather than some abstract visual properties of the object.     

Combining motor and spatial affordance effects with the divided visual field paradigm

The affordance effect has been widely investigated employing various behavioral and brain-imaging techniques. Attempts to interpret the nature of the affordance effect led to two major views. Some researchers compare this kind of compatibility effect to the Simon effect, claiming abstract spatial association between the handle orientation of visually presented stimuli and the nearest response hand. Other authors advocate pure motor activation, during processing of visually presented tools without the involvement of spatial information. However, brain-imaging studies seem to agree that no action can be computed in the absence of spatial information. Taking the latter view into account, a divided visual field experiment was conducted, with the aim of crossing spatial and affordance correspondence effects. Overall, the results supported the view that motor and spatial information go hand in hand. Moreover, the data were in agreement with neuroimaging studies that show tool and affordance processing lateralization in the left hemisphere. The results are discussed in terms of neurophysiological data and brain mechanisms of perception and action.     

Visual object affordances: object orientation

Five experiments systematically investigated whether orientation is a visual object property that affords action. The primary aim was to establish the existence of a pure physical affordance (PPA) of object orientation, independent of any semantic object-action associations or visually salient areas towards which visual attention might be biased. Taken together, the data from these experiments suggest that firstly PPAs of object orientation do exist, and secondly, the behavioural effects that reveal them are larger and more robust when the object appears to be graspable, and is oriented in depth (rather than just frontally) such that its leading edge appears to point outwards in space towards a particular hand of the viewer.     

基于客体的空间一致性效应:功能可见性或空间位置编码?

采用空间Simon任务范式,考察基于客体空间一致性效应到底是手柄的功能可见性引起,还是其空间位置编码导致。实验1采用Pellicano等(2010)研究中的带手柄电筒,要求被试完成与抓握功能相关的形状判断任务,结果表明,唯有当电筒开时,被试产生了基于客体的空间一致性效应。实验2去除电筒可抓握的手柄,发现无论电筒开或关,均出现了更大的基于客体空间一致性效应。上述结果与空间编码假说一致,表明空间位置编码是产生基于客体空间一致性效应的原因。     

Binocular vision enhances a rapidly evolving affordance priming effect: Behavioural and TMS evidence

Extensive research has suggested that simply viewing an object can automatically prime compatible actions for object manipulation, known as affordances. Here we explored the generation of covert motor plans afforded by real objects with precision (‘pinchable’) or whole-hand/power (‘graspable’) grip significance under different types of vision. In Experiment 1, participants viewed real object primes either monocularly or binocularly and responded to orthogonal auditory stimuli by making precision or power grips. Pinchable primes facilitated congruent precision grip responses relative to incongruent power grips, and vice versa for graspable primes, but only in the binocular vision condition. To examine the temporal evolution of the binocular affordance effect, participants in Experiment 2 always viewed the objects binocularly but made no responses, instead receiving a transcranial magnetic stimulation pulse over their primary motor cortex at three different times (150, 300, 450 ms) after prime onset. Motor evoked potentials (MEPs) recorded from a pinching muscle were selectively increased when subjects were primed with a pinchable object, whereas MEPs from a muscle associated with power grips were increased when viewing graspable stimuli. This interaction was obtained both 300 and 450 ms (but not 150 ms) after the visual onset of the prime, characterising for the first time the rapid development of binocular grip-specific affordances predicted by functional accounts of the affordance effect.     

Binocular vision enhances a rapidly evolving affordance priming effect: Behavioural and TMS evidence

Extensive research has suggested that simply viewing an object can automatically prime compatible actions for object manipulation, known as affordances. Here we explored the generation of covert motor plans afforded by real objects with precision (‘pinchable’) or whole-hand/power (‘graspable’) grip significance under different types of vision. In Experiment 1, participants viewed real object primes either monocularly or binocularly and responded to orthogonal auditory stimuli by making precision or power grips. Pinchable primes facilitated congruent precision grip responses relative to incongruent power grips, and vice versa for graspable primes, but only in the binocular vision condition. To examine the temporal evolution of the binocular affordance effect, participants in Experiment 2 always viewed the objects binocularly but made no responses, instead receiving a transcranial magnetic stimulation pulse over their primary motor cortex at three different times (150, 300, 450 ms) after prime onset. Motor evoked potentials (MEPs) recorded from a pinching muscle were selectively increased when subjects were primed with a pinchable object, whereas MEPs from a muscle associated with power grips were increased when viewing graspable stimuli. This interaction was obtained both 300 and 450 ms (but not 150 ms) after the visual onset of the prime, characterising for the first time the rapid development of binocular grip-specific affordances predicted by functional accounts of the affordance effect.     

Vision-for-action: The effects of object property discrimination and action state on affordance compatibility effects

When a person views an object, the action the object evokes appears to be activated independently of the person’s intention to act. We demonstrate two further properties of this vision-to-action process. First, it is not completely automatic, but is determined by the stimulus properties of the object that are attended. Thus, when a person discriminates the shape of an object, action affordance effects are observed; but when a person discriminates an object’s color, no affordance effects are observed. The former, shape property is associated with action, such as how an object might be grasped; the latter, color property is irrelevant to action. Second, we also show that the action state of an object influences evoked action. Thus, active objects, with which current action is implied, produce larger affordance effects than passive objects, with which no action is implied. We suggest that the active object activates action simulation processes similar to those proposed in mirror systems.     

Word‐to‐picture recognition is a function of motor components mappings at the stage of retrieval

Embodied approaches of cognition argue that retrieval involves the re‐enactment of both sensory and motor components of the desired remembering. In this study, we investigated the effect of motor action performed to produce the response in a recognition task when this action is compatible with the affordance of the objects that have to be recognised. In our experiment, participants were first asked to learn a list of words referring to graspable objects, and then told to make recognition judgements on pictures. The pictures represented objects where the graspable part was either pointing to the same or to the opposite side of the “Yes” response key. Results show a robust effect of compatibility between objects affordance and response hand. Moreover, this compatibility improves participants' ability of discrimination, suggesting that motor components are relevant cue for memory judgement at the stage of retrieval in a recognition task. More broadly, our data highlight that memory judgements are a function of motor components mappings at the stage of retrieval.     

Object correspondence across brief occlusion is established on the basis of both spatiotemporal and surface feature cues

The correspondence problem is a classic issue in vision and cognition. Frequent perceptual disruptions, such as saccades and brief occlusion, create gaps in perceptual input. How does the visual system establish correspondence between objects visible before and after the disruption? Current theories hold that object correspondence is established solely on the basis of an object’s spatiotemporal properties and that an object’s surface feature properties (such as color or shape) are not consulted in correspondence operations. In five experiments, we tested the relative contributions of spatiotemporal and surface feature properties to establishing object correspondence across brief occlusion. Correspondence operations were strongly influenced both by the consistency of an object’s spatiotemporal properties across occlusion and by the consistency of an object’s surface feature properties across occlusion. These data argue against the claim that spatiotemporal cues dominate the computation of object correspondence. Instead, the visual system consults multiple sources of relevant information to establish continuity across perceptual disruption.     

The role of affordances in inhibition of return

Inhibition of return (IOR) is a response delay that occurs when the target is preceded by an irrelevant stimulus (cue) at the same location. IOR can be object based, as well as location based. The aim of the present study was to investigate the role of the pragmatic features of a visually presented object in causing IOR. Two experiments were carried out using different objects as stimuli, for which the graspable part (affordance) was clearly defined. The presentation of a whole object, with the part commonly used to grasp it located below, served as a cue. The presentation of either the graspable or the ungraspable part of the cued or uncued object served as the target Results showed that responses were slower when the graspable part was shown in the cued location than when the ungraspable part was shown in the same location. The effect was apparently linked to the kind of action necessary to grasp an object.