The Use Of Object- And Space Based Covert Visual Attention

The human brain is capable of perceiving and interpreting information or stimuli received through the sense organs (i.e., eyes, ears, nose, mouth, and skin) (Weiten, 1998). This ability to perceive and interpret stimulus allows the human being to make meaningful sense of the world and environment around them. However, even as the human being is able to perceive and interpret stimuli information through all sense organs, stimuli is most often or primarily interpreted using the visual (eyes) and auditory (ears) sense organs (Anderson, 2009). However, for the purpose of this paper, the visual information process will be examined.

The Stroop (1935) effect is the inability to ignore a color word when the task is to report the ink color of that word (i.e., to say "green" to the word RED in green ink). The present study investigated whether object-based processing contributes to the Stroop effect. According to this view, observers are unable to ignore irrelevant features of an attended object (Kahneman & Henik, 1981). In three experiments, participants had to name the color of one of two superimposed rectangles and to ignore words that appeared in the relevant object, in the irrelevant object, or in the background. The words were congruent,

Change blindness is a phenomenon in attention where drastic changes to a scene can go unnoticed. This is important to the field of Human Sensation and Perception because it helps illustrate how a visual scene is processed. Specifically it shows how even if there is direct attention to a scene, there are times when drastic changes can occur without perception of the change occurring. With extensive research already conducted illustrating this effect, new research has recently been conducted studying different types of scene changes in the hopes of understanding which changes are easier or harder to notice. The results of these studies were quantified by the measurement of change detection time (usually reported in seconds). This subset of change blindness research has far-reaching practical applications, especially in the field of security and law enforcement. By applying the knowledge of which type of stimuli lead to longer change detection times training programs could be developed that allow this population to improve their observation skills.

This study examined visual perception and the rates at which global and local features are reacted to with an aim of replicating and validating a previous experiment conducted by Navon (1977) to see if global processing was faster than local processing. There was 222 University of Newcastle students participating in the experiment, partaking in two phases, one centred round global processing, the other around local processing, where there reaction times were recorded using a computer program and imputed into a data worksheet. Results indicated that, as predicted, global processing occurred at a faster rate than local processing. It was concluded that global features were

This was achieved by presenting central cues, indicating the position of the target letter thus increasing focus. Through these experiments they found that when a subject is in a diffuse attention state (unfocussed) SOD do cause attentional capture and increase reaction time. However, if the subject was presented with a cue this same increase in reaction time was not observed. This led them to conclude that attentional capture from SOD is not automatic and instead propose a priority based visual attention system. In 2006 Neo and Chua conducted research which built upon Yantis and Jonides’ to further demonstrate effects of attentional capture on reaction time. They investigated whether sporadic use of the SOD increased the effect of attentional capture as well as investigated whether maintaining the same position for the target letter decreased reaction times. They found that SOD attentional capture did affect reaction times and unlike in Yantis and Jonides’ experiment they concluded SOD did trigger an automaticity response when used

The Jelsone-Swain, Smith, & Baylis, (2012), research displays these conclusions provide innovative understandings into the perceptual discrepancies linked with hemineglect and this backups other effort that fabricates the fast denial account of non-awareness dispensation in visual hemispatial neglect.

This study examined whether participant’s response times to global target were faster than local targets. Participants had to identify global and local shapes and letters as quick as possible and the response times which were recorded to the computer data. The study was a replication of Navon’s (1977), (cited in Ness Smith and Thirkettle, 2014) experiment but differed, as it was a focused attention task whereas this experiment was a divided attention task. This was the same as Yovel (2001), (cited in Ness, Smith and Thirkettle, 2014) mixed attention task study which tested the global to local accounts. The current

Powell (1986) conducted a study in which individuals viewed a photo or slide. Individuals were required to scan images and decide on an image for the entire display (Powell, 1986). Objects were pointed to, and subjects were asked to identify its location (Powell, 1986). The subject was asked to close his or her eyes and were shown another image. The subjects were to decide if the object was in the correct position (Powell, 1986). The subjects would hear one of the objects and was required to focus on the object while keeping the entire image in his or her mind (Powell, 1986). When the next object was identified, the subjects were to move from the first object to the second watching a black dot moving in a straight line (Powell, 1986).

The concept of change blindness has been addressed over the course of nearly half a century, with increasing focus on the subject throughout the past five years (3). Although biologists, psychologists, and philosophers have yet to resolve definitively the paradox of looking without seeing, the investigation of each theory on the matter yields deeper insight into visual perception and sight as well as a decreasingly incorrect understanding of those components of the nervous system, which are crucial for visual cognition. Under normal viewing conditions, changes produce transient signals that can draw attention. Change blindness studies are designed to eliminate or block these transient signals by inserting a visual disruption when the change occurs (3). Flicker Paradigm studies examine the occurrence of change blindness and attempt to explain the inability to not see that which is directly in front of our eyes. The Flicker Paradigm demonstrates the essentiality of attention in the process of seeing (4). The alternation of an object and a modified version of that same object is interrupted by millisecond flashes of blank space. Subjects are then asked to report changes in the images.

Researchers do differ on their perspectives on change blindness depending upon their method approach and background or field; however literature is largely in an agreed consensus as to what change blindness is and its effects on attention. Change blindness is studied by using the methodology of change detection, which is where participants are shown two stimuli that are

In previous research, it has been claimed that that ordinary perceivers operate under a grand illusion of perception, and illusion that can be unmasked by change blindness and inattentional blindness. Change blindness and inattentional blindness are phenomena relating to the inability to notice particular stimuli within our visual field, a sort of lapse in our visual system. Change blindness is when a person fails to notice a change within their visual scene because the change occurs during a moment when the intake of visual stimuli is disrupted. Similar to change blindness, inattentional blindness is characterized by the failure to notice a fully visible, but unexpected object because attention is engaged in another object, task, or event. Cohen

Early studies have widely researched attention with selective processing (Driver, 2001). Broadbent (1958) filter theory of attention states that certain information does not require focal attention. It is based on certain stimulus attributes such as colour and shape (Friedenberg, 2012). A previous study carried out by Treisman and Schmidt (1982) proposes that when attention is diverted from a display of several figures, the participants incorrectly combine the features of colour and shape therefore increases the illusory conjunctions portrayed by the participants (Tsal, 1989). Another study by Shaw (1978) found that reaction time of participant to identify targets varied with the probability that a target would appear in a particular display location. These results indicate that different amounts of attention towards the targets are distributed to different positions in the visual field. However, Houck and Hoffman (1986) found that the feature integration of colour and orientation can sometimes be accomplished without attention (James et al.,

In order to provide objective measures of some characteristics of the experimental room, 61 objects in the room were rated on two dimensions: saliency and schema expectancy. The saliency rating was designed to indicate how noticeable an object was in the context of the room. Objects such as the skull and the Skinner box were high on this scale, while objects such as staples and an eraser were low. The schema-expectancy rating was intended to provide an index of subjects’ graduate-student office schema by asking how likely the object was in the context of the room. Objects such as the desk and ceiling lights were high on this scale, while objects such as a model brain and a piece of bark were

The article by Avital-Cohen and Tsal (2016) discussed the flanker task experiment, which asserted that distractor interference happens unconsciously as a result of focused attention toward the target. The results from the original flanker task indicated that participants had slower responses for incongruent trials, since the distractors are inconsistent with the target and would require a different response (Avital-Cohen & Tsal, 2016). However, Avital-Cohen and Tsal (2016) questioned the findings from the flanker task experiment. They decided to challenge the idea that only the target stimuli receives top-down processing, and not the distractors (Avital-Cohen & Tsal, 2016). The first experiment aimed to test whether the distractor interference is purely bottom-up processing as claimed in the flanker task. The experiment manipulated participants’ expectations of the target using the context effect - a type of top-down processing - by changing the distractors to be either letters or digits (Psych 240 lecture, 9/21/16). Then, the researchers conducted a second experiment and eliminated the ambiguity of distractors. They wanted to test whether the result from experiment 1 was caused by an overall bias or the ambiguous distractors. In experiment 2, the researchers predicted that they would obtain similar results to the first experiment only if the results were due to an overall bias effect (Avital-Cohen & Tsal, 2016). This study allows us to deepen our understanding of available

Research carried out on attention has mainly been associated with the selective processing of incoming sensory information. It proposes, to some degree, our awareness of the world depends on what we choose to focus on and not simply the stimulation received by our senses. Attention is often linked to a filter that screens out most potential stimuli whilst allowing a select few to pass through into our conscious awareness, however, a great deal of debate has been devoted to where the filter is situated in the information processing chain (Martindale, 1991). Psychologists have made extensive contributions to this subject matter in the past century. Notable examples include Donald Broadbent's filter theory of attention (1958), which set the