Dissociation of covert and overt spatial attention during prehension movements: Selective interference effects

In four experiments, the influence of distractor objects on the temporal evolution of the reach-tograsp movement toward a target object (an apple) was examined. In the first experiment, the distractor was another apple, which moved laterally behind the target and occasionally changed direction toward the target, thus becoming the to-be-grasped object. In the second and third experiments, the distractor was a stationary piece of fruit, which sometimes became the to-be-grasped object because of a change in illumination. The fourth experiment was a combination of the first two experiments. In all cases, selective interference effects on the transport and manipulation components were observed only when attention to the distractor was covert rather than overt. It is proposed that covert visuospatial attention selects information about distracting but potentially important stimuli, such that a registration of significance is accomplished without the need to process all available information.     

How to accurately detect autobiographical events

ABSTRACT— We describe a new method, based on indirect measures of implicit autobiographical memory, that allows evaluation of which of two contrasting autobiographical events (e.g., crimes) is true for a given individual. Participants were requested to classify sentences describing possible autobiographical events by pressing one of two response keys. Responses were faster when sentences related to truly autobiographical events shared the same response key with other sentences reporting true events and slower when sentences related to truly autobiographical events shared the same response key with sentences reporting false events. This method has possible application in forensic settings and as a lie-detection technique.     

The case of Dr. Jekyll and Mr. Hyde: a kinematic study on social intention

The aim of the present study was to investigate the effects of social intentions on action. Participants (N=13) were requested to reach towards, grasp an object, and either pass it to another person (social condition) or put it on a concave base (single-agent condition). Movements' kinematics was recorded using a three-dimensional motion analysis system. The results indicate that kinematics is sensitive to social intention. Movements performed for the 'social' condition were characterized by a kinematic pattern which differed from those obtained for the 'single-agent' condition. Results are discussed in terms of a motor simulation hypothesis, which assumes that the same mechanisms underlying motor intention are sensitive to social intentions.     

Splitting focal attention.

The study was based on the inverse relationship between the effect of attention on reaction time (RT) and the size of the area over which focal attention is allocated. Independent occurrence of this in 2 locations in the opposite hemifields would be evidence of attention splitting. In Experiment 1, in which the 2 locations were denoted by empty boxes, there was an inverse relationship between size of the stimulated box and RT. Experiment 2 replicated the finding with different stimulation conditions. In Experiment 3, no relationship was found between RT and length of a cuing line. In Experiment 4, in which attention was manipulated by central cues, there was an effect of box size on valid and neutral trials but not invalid trials. Observers could split focal attention and manipulate simultaneously 2 independent attentional foci on objects located in the opposite hemifields.     

How the gaze of others influences object processing

An aspect of gaze processing, which so far has been given little attention, is the influence that intentional gaze processing can have on object processing. Converging evidence from behavioural neuroscience and developmental psychology strongly suggests that objects falling under the gaze of others acquire properties that they would not display if not looked at. Specifically, observing another person gazing at an object enriches that object of motor, affective and status properties that go beyond its chemical or physical structure. A conceptual analysis of available evidence leads to the conclusion that gaze has the potency to transfer to the object the intentionality of the person looking at it.     

Detecting fakers of the autobiographical IAT

Autobiographical memories might be identified using a variant of the implicit association test (IAT), or the autobiographical IAT (aIAT). The aIAT provides a measure of association between true sentences and sentences describing an autobiographical event. This tool might be used to evaluate whether specific autobiographical information is encoded within the respondent's mind/brain. This paper examines possible problems arising when the aIAT is used as a lie‐detector technique. The results indicate that, when given previous instruction or training with an aIAT, examinees can alter their results and beat the ‘memory‐detector’. However, we have been able to detect successful fakers of aIAT on the basis of their specific response patterns. Our algorithm has the ability to spot the faker in a satisfactory manner. If, as demonstrated here, faking can be detected, then the real autobiographical event might also be identified when the examinee attempts to alter their results. Copyright © 2010 John Wiley & Sons, Ltd.     

Cues to intention: the role of movement information

Body movement provides a rich source of cues about other people’s goals and intentions. In the present research, we investigate how well people can distinguish between different social intentions on the basis of movement information. Participants observed a model reaching toward and grasping a wooden block with the intent to cooperate with a partner, compete against an opponent, or perform an individual action. In Experiment 1, a temporal occlusion procedure was used as to determine whether advance information gained during the viewing of the initial phase of an action allowed the observers to discriminate across movements performed with different intentions. In Experiment 2, we examined what kind of cues observers relied upon for the discrimination of intentions by masking selected spatial areas of the model (i.e., the arm or the face) maintaining the same temporal occlusion as for Experiment 1. Results revealed that observers could readily judge whether the object was grasped with the intent to cooperate, compete, or perform an individual action. Seeing the arm was better than seeing the face for discriminating individual movements performed at different speeds (natural-speed vs. fast-speed individual movements). By contrast, seeing the face was better than seeing the arm for discriminating social from individual movements performed at a comparable speed (cooperative vs. natural-speed individual movements, competitive vs. fast-speed individual movements). These results demonstrate that observers are attuned to advance movement information from different cues and that they can use such kind of information to anticipate the future course of an action.     

Your error in my hand: An investigation of observational posterror slowing

Psychonomic Bulletin & Review - For human beings, monitoring others’ errors is essential for efficient goal-directed behavior. Indeed, the mere observation of other individuals’...