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Research has found that the active or passive viewing of a graspable object produces the associated motor representation in motor cortical regions of the brain. As the brain views the object, the representation of actions associated with the graspable features are formed, even if there is no requirement to act on the object (Grèzes, Tucker, Armony, Ellis, & Passingham, 2003). Researchers have theorized that when the brain is identifying an object, activation of both stored sensory and motor representations will occur (Chao & Martin, 2000). Research has also shown that the motor representation associated with using the graspable object can interfere with an individual’s ability to carry out a reach and grasp action (Till, Masson, Bub, & Driessen, 2014). One theory is that the planning and executing of the intended action is competing with the motor plans the brain has created for grasping the object (Cisek, 2007).
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In their study, Tucker and Ellis (1998) had participants consciously view a graspable object and respond with either a left or right button press to whether the object was upright or inverted. Their results showed that when the handle was on the same side as the responding hand, responses were faster; this is known as the alignment effect (Tucker & Ellis, 1998). Tucker and Ellis’s study focuses on the conscious processing of the graspable object. The evidence provided by previous studies does not address an important issue, the presence of interference on the unconscious processing of a graspable object on an unrelated action; in this study we want to determine if unconscious processing of an object’s graspable features is enough to create a motor representation that will interfere with the planning and execution of the key press.
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Research has found that the active or passive viewing of a graspable object produces the associated motor representation in motor cortical regions of the brain. When we view the picture of a graspable object, whether we look passively or actively, evidence indicates that the depicted object triggers activity in regions of the motor cortex. What kinds of graspable object? A cellphone? A climbing hold? A novel object? What is the difference between “active” and “passive” viewing?
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These authors gave a name to demarcate this phenomenon:
Passive viewing “…..when a graspable object such as a coffee cup comes into view, a variety of parietal and prefrontal regions have been shown to respond to that object independent of the observers intention to act—a phenomenon we will refer to here as an implicit visuomotor response, or iVMR” an IVMR These authors gave a name to demarcate this phenomenon: implicit - because you are not required to explicitly attend visuomotor - because the visual image of an object triggers motor cortical regions response - we assume this motor representation is linked to the planning of an action
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Active viewing? Presumably viewing the object when you are explicitly paying attention. To what, though? It’s identity? - e.g. that’s a spray can The action you make on it to accomplish it’s proper function? You use it like this…. An indication of the object’s abstract functional properties? You use it to produce a spray of liquid. Too many complexities are raised by the term “active viewing”. It would take a lot of work to define, and this is unnecessary for an introductory paragraph.
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Research has found that the active or passive viewing of a graspable object produces the associated motor representation in motor cortical regions of the brain. Activation in motor cortical regions is produced by images of graspable objects like beer mugs and frying pans, even when observers are merely asked to passively view them. As the brain views the object, the representation of actions associated with the graspable features are formed, even if there is no requirement to act on the object (Grèzes, Tucker, Armony, Ellis, & Passingham, 2003). This sentence is not adding much to the previous sentence
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Activation in motor cortical regions is produced by images
of graspable objects like beer mugs and frying pans, even when observers are merely asked to passively view them. Researchers have theorized that when the brain is identifying an object, activation of both stored sensory and motor representations will occur (Chao & Martin, 2000). This evidence has lead to the assumption that visible objects automatically give rise to components of actions they afford.
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Research has also shown that the motor representation associated with using the graspable object can interfere with an individual’s ability to carry out a reach and grasp action (Till, Masson, Bub, & Driessen, 2014). One theory is that the planning and executing of the intended action is competing with the motor plans the brain has created for grasping the object (Cisek, 2007). Competition between actions may occur when an intended response conflicts with motor representations implicitly triggered by the object.
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Activation in motor cortical regions is produced by images
of graspable objects like beer mugs and frying pans, even when observers are merely asked to passively view them. This evidence has lead to the assumption that visible objects automatically give rise to components of actions they afford. Competition between actions may occur when an intended response conflicts with motor representations implicitly triggered by the object. This competition might affect speeded responses to an object under suitable task conditions.
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Now we need to describe as economically but as clearly
In their study, Tucker and Ellis (1998) had participants consciously view a graspable object and respond with either a left or right button press to whether the object was upright or inverted. Now we need to describe as economically but as clearly as possible, (a) what Tucker and Ellis did in their experiment (i.e. the task that subjects performed) and (b) why they felt the evidence supported their claim that “…representing visual information involves representing information about possible actions and thereby potentiating them.”
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From: Journal of Experimental Psychology: Human Perception and Performance (in press, March 2017) Time Course of Motor Affordances Evoked by Pictured Objects and Words Daniel N. Bub, Michael E. J. Masson, and Ragav Kumar University of Victoria
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Tucker and Ellis “….required observers to indicate with a keypress using their left/right hand whether the depicted object was in an upright or inverted orientation. Performance was faster when the position of the handle on the left or right matched rather than mismatched the left/right hand making the keypress response. A second experiment involving responses with the index and middle fingers of one hand assigned to a left- versus right-sided keypress yielded no such correspondence effects.
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Given the specificity of the effect, Tucker and Ellis inferred that upright/inverted judgements to pictured objects were affected by an objects’ perceived graspability (that is, the relative ease with which the depicted object is seen to be graspable using the left or right hand). Because this factor was irrelevant to the task of judging whether the object was upright or inverted, these authors concluded that perception automatically generates possible actions associated with an object. If this claim is correct, it follows that the role of intentions is merely to select from already potentiated visuomotor representations.
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The statement needs work!
This next section must provide us with a clear understanding of the goal of the Emma’s thesis. She begins with: The evidence provided by previous studies does not address an important issue, the presence of interference on the unconscious processing of a graspable object on an unrelated action; The important issue: the presence of interference on the unconscious processing of a graspable object on an unrelated action The statement needs work!
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Let’s look at the whole sentence again:
Emma tries to clarify: in this study we want to determine if unconscious processing of an object’s graspable features is enough to create a motor representation that will interfere with the planning and execution of the key press. Let’s look at the whole sentence again: The evidence provided by previous studies does not address an important issue, the presence of interference on the unconscious processing of a graspable object on an unrelated action; in this study we want to determine if unconscious processing of an object’s graspable features is enough to create a motor representation that will interfere with the planning and execution of the key press.
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The term “unconscious” is adding another layer of theory
Remember the term “experience” Sentence is too long The term “unconscious” is adding another layer of theory that is not part of the meaning of “unintentional" versus “intentional”. Conscious: intended versus unintended. Unconscious: intended? unintended. The evidence provided by previous studies does not address an important issue, the presence of interference on the unconscious processing of a graspable object on an unrelated action The evidence provided by previous studies does not address an important issue, the interference generated by the unconscious processing of a graspable object on an unrelated action.
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Tucker and Ellis: Unintended Processing Intended Processing
The evidence provided by previous studies does not address an important issue, the interference generated by the unintended processing of a graspable object on an intended action. left/right orientation Tucker and Ellis: The first experiment showed that the left-right orientation of common graspable objects had a significant effect on the speed with which a particular hand made a simple push-button response, even though the horizontal object orientation was irrelevant to response determination. Unintended Processing Intended Processing
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The evidence provided by previous studies does not address an important issue, the interference
generated by the unintended processing of a graspable object on an intended action. It does!
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Activation in motor cortical regions is produced by images
of graspable objects like beer mugs and frying pans, even when observers are merely asked to passively view them. This evidence has lead to the assumption that visible objects automatically give rise to components of actions they afford. Competition between actions may occur when an intended response conflicts with motor representations implicitly triggered by the object. This competition might affect speeded responses to an object under suitable task conditions.
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Some behavioural evidence is consistent with this set of conjectures
Some behavioural evidence is consistent with this set of conjectures. Tucker and Ellis “….required observers to indicate with a keypress using their left/right hand whether the depicted object was in an upright or inverted orientation. Performance was faster when the position of the handle on the left or right matched rather than mismatched the left/right hand making the keypress response. A second experiment involving responses with the index and middle fingers of one hand assigned to a left- versus right-sided keypress yielded no such correspondence effects.
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Given the specificity of the effect, Tucker and Ellis inferred that upright/inverted judgements to pictured objects were affected by an objects’ perceived graspability (that is, the relative ease with which the depicted object is seen to be graspable using the left or right hand). Because this factor was irrelevant to the task of judging whether the object was upright or inverted, these authors concluded that perception automatically generates possible actions associated with an object. Assuming this claim is correct, it follows that the role of intentions is merely to select from already potentiated visuomotor representations.
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The structure of the next paragraph which will
introduce the motivation behind Emma’s research (in general terms; she will go into detail later).
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How reliable is the evidence put forward by Tucker and Ellis?
These authors “….required observers to indicate with a keypress using their left/right hand whether the depicted object was in an upright or inverted orientation. Performance was faster when the position of the handle on the left or right matched rather than mismatched the left/right hand making the keypress response. A second experiment involving responses with the index and middle fingers of one hand assigned to a left- versus right-sided keypress yielded no such correspondence effects. The specificity of the alignment effect led Tucker and Ellis (1998) to argue that keypress responses were influenced by the "... relative ease with which the objects could be grasped by the left or right hand" (p. 843). How reliable is the evidence put forward by Tucker and Ellis? Is it really true that visual objects trigger features of actions regardless of the intentions of an observer. If not, what is the relationship between the intention to act (motor intentions) and the features evoked by the picture of an object?
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Unfortunately, numerous attempts to replicate the effects
reported by Tucker and Ellis have been unsuccessful. When handle alignment effects occur, they are generally of the same magnitude, whether responses are carried out with two fingers of a single hand (Cho & Proctor, 210), two hands, two feet (Phillips & Ward, 2002), or with the hands crossed such that the left key is pressed with the right index finger and the right key with the left index finger (Phillips & Ward, 2002). The evidence indicates that objects do not automatically trigger features of action that affect left- versus right-handed keypress responses. Instead, effects are due to abstract spatial codes induced by the projection of the handle on the left or right. The relationship between motor intentions and constituents of action generated by a depicted object remains to be clarified.
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Activation in motor cortical regions is produced by images
of graspable objects like beer mugs and frying pans, even when observers are merely asked to passively view them. This evidence has lead to the assumption that visible objects automatically give rise to components of actions they afford. Competition between actions may occur when an intended response conflicts with motor representations implicitly triggered by the object. This competition should affect speeded responses to an object under suitable task conditions.
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Some behavioural evidence is consistent with this set of conjectures
Some behavioural evidence is consistent with this set of conjectures. Tucker and Ellis “….required observers to indicate with a keypress using their left/right hand whether the depicted object was in an upright or inverted orientation. Performance was faster when the position of the handle on the left or right matched rather than mismatched the left/right hand making the keypress response. A second experiment involving responses with the index and middle fingers of one hand assigned to a left- versus right-sided keypress yielded no such correspondence effects.”
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Given the specificity of the effect, Tucker and Ellis inferred that upright/inverted judgements to pictured objects were affected by an objects’ perceived graspability (that is, the relative ease with which the depicted object is seen to be graspable using the left or right hand). Because this factor was irrelevant to the task of judging whether the object was upright or inverted, these authors concluded that perception automatically generates possible actions associated with an object. Assuming this claim is correct, it follows that the role of intentions is merely to select from already potentiated visuomotor representations.
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Unfortunately, numerous attempts to replicate the effects
reported by Tucker and Ellis have been unsuccessful. When handle alignment effects occur, they are generally of the same magnitude, whether responses are carried out with two fingers of a single hand (Cho & Proctor, 210), two hands, two feet (Phillips & Ward, 2002), or with the hands crossed such that the left key is pressed with the right index finger and the right key with the left index finger (Phillips & Ward, 2002). The evidence indicates that objects do not automatically trigger features of action that affect left- versus right-handed keypress responses. Instead, effects are due to abstract spatial codes induced by the projection of the handle on the left or right, affecting any left versus right-sided response. The relationship between motor intentions and constituents of action generated by a depicted object remains to be clarified.
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Under what task conditions, if any, do pictures of objects evoke components of grasp actions?
The purpose if this thesis is to pursue and further extend the following claim: that when observers plan or execute cued reach-and-grasp actions, the picture of a task-irrelevant object yields effects on speeded responses that bear the hallmarks of motor rather than abstract spatial codes. This evidence, summarized and recently extended in Bub, Masson & Kumar (2017), implies that motor goals modulate the correspondence effects induced by images of graspable objects. In other words, the task set of engaging in reach-and-grasp grasp actions itself plays a crucial role in triggering motor constituents from depicted objects.
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The findings suggest that perception of climbing holds activates the commonly associated grasping postures in climbers but not in non-climbers.
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iVMR= implicit visuomotor response
……..rather than depending on motor experience with a graspable object, it appears that implicit iVMRs under passive viewing conditions may be more strongly associated with a lack of direct real-world motor experience. Second, in addition to this reduced visuomotor-related activity, motor experience with a graspable object also appears to reduce activity in visual cortex. In short, graspable objects unfamiliar to the motor system (climbing holds in Experiment 1) generated responses in left parietal and prefrontal cortex that were consistent with an iVMR, as well as activations in visual cortex that extended from lateral occipital regions into ventral temporal areas. Conversely, graspable objects familiar to the motor system through repeated real-world experience (door knobs in both Experiments 1 and 2 and climbing holds in Experiment 2) failed to generate iVMRs and had activity in visual cortex that was limited to lateral occipital regions only
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