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Full-Text Articles in Psychology
Are Greebles Like Faces? Using The Neuropsychological Exception To Test The Rule., Isabel Gauthier, Marlene Behrmann, Michael Tarr
Are Greebles Like Faces? Using The Neuropsychological Exception To Test The Rule., Isabel Gauthier, Marlene Behrmann, Michael Tarr
Marlene Behrmann
Which image geometries count as face-like and which do not? Across multiple experiments, novel objects called Greebles have been used to argue that face-specific effects can be obtained with non-face stimuli under certain situations, in particular with expert observers. However, this claim depends on the argument that these non-face stimuli are not a priori treated by the face processing system. To address this question, CK, a neuropsychological patient well-known for exhibiting severe visual object agnosia and dyslexia but intact face processing, was tested with Greebles. CK performed poorly on Greebles, indicating that his intact face-specific abilities do not extend to …
The Influence Of Competing Perceptual And Motor Priors In The Context Of The Size-Weight Illusion, Gavin Buckingham, Melvyn Goodale
The Influence Of Competing Perceptual And Motor Priors In The Context Of The Size-Weight Illusion, Gavin Buckingham, Melvyn Goodale
Gavin Buckingham
When lifting objects of identical mass but different sizes, people perceive the smaller objects as weighing more than the larger ones (the 'size-weight' illusion, SWI). While individual's grip and load force rates are rapidly scaled to the objects' actual mass, the magnitude of the force used to lift these SWI-inducing objects is rarely discussed. Here, we show that participants continue to apply a greater loading force to a large SWI-inducing cube than to a small SWI cube, lift after lift. These differences in load force persisted long after initial errors in grip and load force rates had been corrected. Interestingly, …
Gating Of Vibrotactile Detection During Visually Guided Bimanual Reaches, Gavin Buckingham, David Carey, Francisco Colino, John Degrosbois, Gordon Binsted
Gating Of Vibrotactile Detection During Visually Guided Bimanual Reaches, Gavin Buckingham, David Carey, Francisco Colino, John Degrosbois, Gordon Binsted
Gavin Buckingham
It is far more difficult to detect a small tactile stimulation on a finger that is moving compared to when it is static. This suppression of tactile information during motion, known as tactile gating, has been examined in some detail during single-joint movements. However, the existence and time course of this gating has yet to be examined during visually guided multi-joint reaches, where sensory feedback may be paramount. The current study demonstrated that neurologically intact humans are unable to detect a small vibratory stimulus on one of their index fingers during a bimanual reach toward visual targets. By parametrically altering …
Living In A Material World: How Visual Cues To Material Properties Affect The Way That We Lift Objects And Perceive Their Weight, Gavin Buckingham, Jonathan Cant, Melvyn Goodale
Living In A Material World: How Visual Cues To Material Properties Affect The Way That We Lift Objects And Perceive Their Weight, Gavin Buckingham, Jonathan Cant, Melvyn Goodale
Gavin Buckingham
The visual properties of an object provide many cues as to the tensile strength, compliance, and density of the material from which it is made. However, it is not well understood how these implicit associations affect our perceptions of these properties and how they determine the initial forces that are applied when an object is picked up. Here we examine the effects of these cues on such forces by using the classic "material-weight illusion" (MWI). Grip and load forces were measured in three experiments as participants lifted cubes made from metal, wood, and expanded polystyrene. These cubes were adjusted to …
A Role Of The Basal Ganglia In Movement: The Effect Of Precues On Discrete Bi-Directional Movements In Parkinson's Disease, Andrew Johnson, Philip Vernon, Quincy Almeida, Linda Grantier, Mandar Jog
A Role Of The Basal Ganglia In Movement: The Effect Of Precues On Discrete Bi-Directional Movements In Parkinson's Disease, Andrew Johnson, Philip Vernon, Quincy Almeida, Linda Grantier, Mandar Jog
Andrew M. Johnson
The effect of a precue on improving movement initiation (i.e., reaction time; RT) is well understood, whereas its influence on movement execution (i.e., movement time; MT) has rarely been examined. The current study investigated the influence of a directional precue (i.e., left vs. right) on the RT and MT of simple and discrete bi-directional movements in a large sample of Parkinson's disease patients and healthy control participants. Both patients and controls were tested twice, with testing sessions separated by 2 hours. Patients were tested first following an overnight levodopa withdrawal and again after they had taken their medication. Both patients …