Attention in Vision: Perception, Communication and Action

Visual attention and stability

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So in figure 4 the lines on the left are perceived as an incomplete circle, rather than four curves and likewise with the incomplete square. Likewise, the panda figure 5 is perceived to be whole, even though there is no line indicating this. Most of the Gestalt laws are focused on static two-dimensional shapes. This is the law of common fate and can be observed by lights in a dark background. These lights seem to be separate unless they move together. This can be observed in this moving image: Is visual attention location or object based? Do we pay visual attention to the regions of space within a visual scene or directly to specific objects regardless their spatial context?

What we know for sure, visual attention is very selective. Proposed analogies for location based visual attention - The idea is the same for all of them: Evidence for object based visual attention - Attention selects from objects themselves, rather than potentially empty regions of space. General consensus on location vs. Pop-out effect happens when one perceptual feature of the target is different shape, colour, size, If features differs in conjunction, we need attention to glue these features and to apply serial search.

Proposed evidence - Illusory conjunctions , Dual route - dorsal spatial vs. Theory proposes that we're able to bind visual features into so called Object Files in order to maintain changes during relative movement without repeated binding:. In order for objects to be tracked, they must maintain a spatio-temporally plausible path of motion, even if occlusion occurs.

Object-files are sticky, but motion must be consistent with reality and expectations. Models of object-recognition need to be able to allow accurate performance regardless of viewing conditions. Viewpoint-dependent theories suggest that object recognition is affected by the viewpoint at which it is seen, implying that objects seen in novel viewpoints reduce the accuracy and speed of object identification.

We must also account the context influence - e. Gestalt theory was introduced in the field of psychology in Its major contributors were Wesheimer, Koffka, and Kohler Ware, Gestalt aimed to explain the way people perceive structures in the environment by examining psychological phenomena. Most theories of the time like structuralism and behaviourism were analysing an experience as a sum of components, which were studied in isolation.

The proposed solution was encapsulating the solutions of the isolated elements Wertheimer, a.

As Wertheimer a explicitly states:. It is the hope of Gestalt theory to determine the nature of such wholes. As it is concluded, Gestalt theory adapts the notion that people tend to organise elements in large units.

On the role of selective attention in visual perception

It can be considered a bottom-up approach in a sense that reaches complex cognitive processes starting from simple elements that stimulate the perception Carlson and Heth, From another point of view, it can also be assessed as a top-down approach as it highlights the effect of the context and holism Soegaard, , which also hold a key role in the contemporary research in the field of Human-Computer Interaction.

In the New Bahaus in Chicago, used illustrations by Wertheimer, Koffka, and Kohler to assist his discussion of the laws of visual organization and psychological forces. Some major contributors have been Professor Rudolf Arnheim and Roy Behrens, who in incorporated Gestalt in her interactive media Design curriculum.

Even though there has been considerable literature on Graphic and visual design and Gestalt, little has been mentioned in connection to website and particularly to interaction design and its relation to its main principles. We hereby will venture to include Gestalt's correlation to interactivity and later on "Interaction Gestalt" as coined by Lim et al, and its importance in HCI, aesthetics and User Experience. In that sense, Youn-kyung Lim and colleagues offer the concept of interaction gestalt as a bridge between the interactive product and experience.

They provide eleven attributes to describe those gestalts, such as pace, speed, proximity and so forth. The authors emphasise that these properties 'are not experience qualitiesthey are simply descriptions of the shape of the interaction' Lim et al. Through Gestalt principles they propose a triad of questions to design gestalt interactions:.

It is important to understand that the attributes are not supposed to be used individually. As the original meaning of gestalt tells us, the sum is different from the whole. Designers should have knowledge of how to shape aesthetic interactions in a more visible, explicit, and designerly way. This is a kind of knowledge we are currently missing in HCI. Shaping the gestalt involves both imaging how the gestalt should be manifested in an interactive artefact as well as anticipating how users will experience the gestalt.

The interaction gestalt also has to be designed in a way that will evoke the desired user experiences Traditionally in HCI, interactions have been described by languages of. Although all these approaches have helped conceptualising and shaping interface designs, they have not directly supported the aspect of aesthetics when designing interactive artefacts. Lim et al, What designers explore with the idea of interaction gestalt is the space of emerging shapes of interactions; it is not about how interfaces look like or what features need to be implemented.

Gestalt has produced laws of perception that describe the way people pereive patterns in visual images. Specifically, they propose means of organising visual elements effectively into structures Chang et al, These laws provided designers with a powerful, comprehensible and scientific method to group design elements efficiently refering to the layout as a whole rather than its individual parts. Thus, the principles of Gestalt were adopted mostly in visual communication but also in other disciplines like architecture, human-computer interaction and linguistics Graham, There were originally laws introduced but most of them were very similar and overlapping.

As a result only a few of them were practically meaningful and gained ground in the practical field. The color of the links is too similar to that of the background in both the normal and the over states, making it difficult for the user to readily discern that an active feature is in place Figure numbering is not continued from the start of the page and re-starts as 'Figure 1'. Will update this to the correct numbering as needed, once other diagrams make it into the chapter. In addition to the Gestalt principles of proximity and similarity, object features and concepts of uniform connectedness , the configural superiority effect and figure-ground segregation influence how people perceive grouping.

These are discussed later in the section. Proximity and similarity in the natural world is indicative of a closer relationship; for instance, diseases are passed between people in close contact with each other faster than those who are distant proximity and creatures will tend to form communities within a species similarity. Translated to the perception of visual information, closeness and similarity in the display will be taken to represent relatedness and, therefore, will facilitate perceptual grouping.

Features of objects also influence perceptual grouping. See Figure 1, below. The dotted line indicates how perceptual grouping should occur. Initially, humans will group objects by proximity and similarity with a roughly equal proportion favouring each.

However, if objects are already grouped by proximity, additional processes occur. If there are differences between the items within a cluster e. The same concept can be applied between clusters: In Situation A , there are no conflicts, so the principle of proximity will dominate. In Situation B , the principles of proximity and similarity will prevail.

In Situation C , observers will choose either between the principle of proximity or the principle of similarity. In Situation D , observers often ignore proximity and base their perceptual grouping on colour above shape and texture. Uniform connectedness refers to the tendency to group connected regions that share the same properties, e. It has been found to dominate the principle of similarity for all conditions and proximity when more than two objects are presented. This supports the suggestion that it occurs earlier in the perceptive process, although to what extent requires further investigation Eysenck and Keane, Most research in this area has been based on artificial figures, and further investigation is required to identify the extent to which these concepts can be applied to real-world situations.

The configural superiority effect describes how perception of grouping is affected more by organisation than complexity. In other words, it is easier to comprehend complex items that are organised clearly, than simple items that are organised badly. For designers, this emphasises the need to consider visual grouping and perception when communicating complex data Pomerantz, in Eysenck and Keane, Observers pay more attention to the main figure, thus perceiving it more clearly facilitating improved recall and less to the ground.

See the famous faces-goblet illusion for example, Figure 3. When the goblet is the object of interest - the figure - it appears in front of a white background. However, when the faces are the figure, they appear on black background ground. Applying the concepts of perceptual grouping to the design of visual displays first and foremost requires knowledge of the users and their goals. Draw attention to task-relevant information figure and eliminate irrelevant information ground. Psychological pop out also referred as visual pop outs are characterised as visual objects that are the most salient in a display thereby grabbing visual attention.

Research in this area refer to the process of identifying pop outs as pre-attentive parallel processing whereby the entire visual field is scanned for basic features such as colour, contrast, line closure, line ends, contrast, tilt curvatures and size. Research gauging the processing of pop outs relies on measuring the reaction times ms of participants in identifying target pop out features. From the findings, there is consensus for pop out objects having basic features which are unique from objects in the same visual field.

These are very simple examples of object features that are scanned for pop outs, examination of the research reveal that saliency has to be rapidly distinguishable in the pre-attentive process otherwise serial processing occurs whereby each object in the visual field is scanned one-by-one, a slower process. Hence, while a red circle in an array of green circles will pop out, a red circle in a field of red squares and green circles will not as the features of colour and shape of the unique object are shared by other objects.

Krummenacher et al Familiarity of objects assist in identifying pop outs more rapidly but only when familiar objects serve as distractors rather than target pop outs. Luck and Hillyard found that if users expected target information in a pop out, this would further influence pop out detection. A previous editor has left these references here. This section should be expanded and the references should be moved to the references section at the bottom of the page - Sandy. With the vast amount of information in the world, perceived via all of our senses, it is important that we have a mechanism that prevents us from suffering from information overload.

In other words, it is important to have a mechanism enabling us to optimise our limited informational processing resources towards stimuli that are relevant to our survival and goals. Attention is such a mechanism, which facilitates what we perceive and how we can act upon what we perceive. More specifically, attention enables us to reduce processing of irrelevant stimuli; enhance relevant stimuli; bind incoming information signals into coherent representations of the world; and recognise stimuli Evans et al.

One of the earlier famous definitions of attention was given by the pioneering psychologist William James in It is the taking possession by the mind, in clear and vivid form, of one out of what seem several simultaneously possible objects or trains of thought. Focalisation, concentration of consciousness are of its essence. It implies withdrawal from some things in order to deal effectively with others. This definition highlights the selective nature of attention. Selective attention may for instance occur when you search the item listing of an online shopping website for a specific household item.

During tasks such as this, some pieces of information are registered, whereas other information is ignored. An example of divided attention is when you are trying to type up a coursework assignment while simultaneously chatting with a friend on Facebook. The limitations of the amount of incoming information you can process, i.

James' definition also focuses on attention as a conscious process - however, this notion has been qualified in later models. A common criticism of the automaticity model is the notion that automatic processing does not affect attentional resources. The Stroop effect is an infamous example of how attention directed towards a specific task can be detrimentally affected by automatically processed tasks: The various forms and processes of attention are underpinned by the sensory modalities.

The modalities of vision, hearing and touch all contribute to our sense of attention individually and collectively. Below we will give an overview of the major modalities and how they operate, and we will look briefly at cross-modal attention. Perhaps one of the most studied modalities for attention is that of vision.

For focused visual attention there are two systems, one stimulus-driven and the other goal-directed. Although they utilize different parts of the brain, they interact and can influence each other.

Furthermore, the focus of attention can be location-based and object-based. Finally, susceptibility to distraction is influenced by the perceptual load and executive cognitive control needed for the task. Perceptual load refers to the amount of stimuli and processing power needed for each stimulus. Executive cognitive control is concerned with higher functions such as memory. The more perceptual load needed for a task the less impact there is from distracting stimuli, however higher levels of executive cognitive control result in increasing impact of distractions Lavie, Dichotic listening tests have been used to study attention in the auditory mode.

Participants are simultaneously presented with two different auditory stimuli and then asked to distinguish between the two and recall the content of either message. Cherry used the selective attention experiment where the participant repeats aloud the content of one of the messages - known as shadowing.

Cherry found that people recall the shadowed message poorly, suggesting that most of the processing necessary to shadow occurs in working memory and is not stored in the long-term memory. Two simultaneous messages gain access at the same time to a sensory buffer. One of the inputs is then allowed through a filter on the basis of its physical characteristics, with the other input remaining in the buffer for later processing. This filter prevents overloading of the limited capacity mechanism beyond the filter, which processes the input thoroughly e. Criticism of this theory suggests it cannot account for variability in the amount of analysis of the non-shadowed message.

Treisman claimed that the location of the bottleneck was more flexible than Broadbent had suggested. There is complete perceptual analysis of all stimuli so there should be no difference in detection rates between the two messages. More recent studies have supported both the Treisman and Broadbent approach although there are limitations of research in this area:. Our sensory modalities do not operate independently of one another, in actual fact we use multiple senses at the same time.

Cross-modal attention is the coordination of input from varying modalities Driver and Spence. Lip reading is a good example of cross modal attention, where input from 2 modalities in this case audition and vision are co-ordinated. Interesting illusions can results when sensory modalities combine, as witnessed with the McGurk Effect. The McGurk effect is an illusion that combines auditory and visual perception.

What you see influences what you hear. As opposed to interpretation emerging from observation, or bottom-up processing, top-down processing suggests that interpretation is influenced largely by knowledge, expectations, tasks and goals. This means that the context of the task and the goals of the individuals will have a strong infleunce on the processing of information and the cognitive approach to search. They identified that, on a neurological level, different parts of the brain are utilised in activating top-down selection to that of the bottom-up system. The influence of goals on attention has been demonstrated using eye tracking systems.

One such study was carried out by Yarbus ; participants were initially asked to look freely at a painting, and eye saccades were mapped fig. Here the fixations are clearly on the faces of the people, and less on the environment in general. Attention is a selection mechanism in human mind which depends on the interaction between exogenous and endogenous factors Posner, Definition of Bottom-up and Top-down. There are two types of attention models.

One is the bottom-up processing which makes the attention be driven by the salient visual properties of the objects. For example, the figure1. In the figure 1. Human assigns the priority of attention to objects based on the task, behavioural goals or prior knowledge Hornof and Halverson, The spiky diamond in the center is the most salient for most people in their first sight because of its unique shape. However, if there is a task which required to find out other normal geometric shapes, e. The attention will be influenced. In order to study the relationship between the bottom-up and top-down, the visual search experiments involving eye tracking are always used.

However, in many situations, the attentions are always based on both the bottom-up and top-down. Back to the figure above, the observer know what is the target. Simultaneously, the most salient item will still draw some attention as well. The former is the top-down and the latter is the bottom-up.

Nevertheless, if some changes were made to figure 2. Then the inference from the bottom-up will be reduced when top-down is needed. Besides the way above, there is another approach benefiting the reduction of bottom-up salience. It is to increase the diversity of the distractors. Actually, it also helps to reduce the saliency the most salient item. Apparently, the top-down process is an intentional, deliberate, voluntary, effortful mental process, and it has a sustained time course Yantis, On the other hand, the bottom-up process is an autonomous process, and it has a rapid time course Posner et al.

However, these two processes are not separated when human allocates the attention on objects. They are influencing and interacting with each other Grossberg, Mingolla and Ross, ; Muller, Humphreys and Donnelly, For instance, the famous researches of abrupt onsets showed that abrupt onsets draw attention even when there is no informative cues Yantis and Jonides, and when the subjects were encouraged to ignore the cues Jonides, At the same time, other researches also showed that although the task goals determined whether to ignore a singleton or not, other task-irrelevant dimensions automatically draw attention at the same time Pashler, We can take Fig.

Undoubtedly, most of people will pay attention to the full-blown flower in the middle at first sight when they see this picture, rather than notice the shape and quantity of leaves in the corner or the color of the metal baluster under the flower. Why the focus of attention of people like this? Its color is orange, which high contracts the green background and makes itself standing out from the whole picture. In other word, this bright color is physical input and gives human visual stimulus and the bottom-up stimulus-driven control of attention leads people to look at this flower.

In some situation, the flashy Ads can catch attention of people is on the same theory. Another possibility is that the flower is the biggest object in the centre of the picture, which will let people consider this flower as the target object of the photographer. So that viewers will think the full-blown flower as the main character and other things are the background of the picture. Under this cognition, people will pay more attention on main character rather that background. This is what we said Top-down concept-driven control of attention. In Figure 1, both bottom-up and top-down controls of attention focus on the same object, the flower, so we will look at it without conflict.

Physiology, psychology and ecology 4th ed. Psychology the Science of Behaviour 4 th ed. Gestalt Theory in Visual Screen Design: A New Look at an Old Subject. Australian Computer Society, Inc. Some experiments on the recognition of speech, with one and two ears. Journal of the Acoustical Society of America. Control of goal-directed and stimulus-driven attention in the brain. Cross-modal links in spatial attention. Philosophical transactions of the Royal Society of London. Series B, Biological sciences , Psychology Press, East Sussex.

Gestalt theory, engagement and interaction. The Biology of the Mind. Gestalt Theory in Interactive Media Design. A neural theory of attentive visual search: Interactions of boundary, surface, spatial, and object representations.

Perception, Action, Attention and Communication (Dr. Fantoni)

Psychological Review , 3 , Hassenzahl, M , "Experience Design: Simplicity Versus Likelihood in Visual Perception: In Treatise on physiological optics, vol. III, 3rd edn translated by J. Section 26, reprinted New York: Implications for Design, Topics in Cognitive Science 3 Cognitive strategies and eye movements for searching hierarchical computer displays. Voluntary versus automatic control over the mind's eye. Selective attention under load.

Trends in Cognitive Sciences , 9 2 , Interaction gestalt and the design of aesthetic interactions. Theories of vision from al-Kindi to Kepler. The University of Chicago Press, Using Gestalt theory to teach document design and graphics. Technical Communication Quarterly, 2, Visual search for single and dual form-conjunction targets. Journal of Experimental Psychology: Cross-dimensional interaction and texture segregation.

Theoretical approaches to perceptual organization: Simplicity and likelihood principles. As Rastophopoulos summarizes the debate: In the twentieth century, the pioneering research of Lev Vygotsky and Alexander Luria led to the three-part model of neuropsychology defining the working brain as being represented by three co-active processes listed as Attention, Memory, and Activation. Attention is identified as one of the three major co-active processes of the working brain.

Luria published his well-known book The Working Brain in as a concise adjunct volume to his previous book Higher Cortical Functions in Man. In this volume, Luria summarized his three-part global theory of the working brain as being composed of three constantly co-active processes which he described as the; 1 Attention system, 2 Mnestic memory system, and 3 Cortical activation system. The two books together are considered by Homskaya's account as "among Luria's major works in neuropsychology, most fully reflecting all the aspects theoretical, clinical, experimental of this new discipline.

Multitasking can be defined as the attempt to perform two or more tasks simultaneously; however, research shows that when multitasking, people make more mistakes or perform their tasks more slowly. In divided attention, individuals attend or give attention to multiple sources of information at once at the same time or perform more than one task.

Perception, Action, Attention and Communication (Dr. Fantoni) | Department of Life Sciences

Older research involved looking at the limits of people performing simultaneous tasks like reading stories, while listening and writing something else, [15] or listening to two separate messages through different ears i. Generally, classical research into attention investigated the ability of people to learn new information when there were multiple tasks to be performed, or to probe the limits of our perception c. There is also older literature on people's performance on multiple tasks performed simultaneously, such as driving a car while tuning a radio [16] or driving while telephoning.

The vast majority of current research on human multitasking is based on performance of doing two tasks simultaneously, [13] usually that involves driving while performing another task, such as texting, eating, or even speaking to passengers in the vehicle, or with a friend over a cellphone. This research reveals that the human attentional system has limits for what it can process: There has been little difference found between speaking on a hands-free cell phone or a hand-held cell phone, [21] [22] which suggests that it is the strain of attentional system that causes problems, rather than what the driver is doing with his or her hands.

While speaking with a passenger is as cognitively demanding as speaking with a friend over the phone, [23] passengers are able to change the conversation based upon the needs of the driver. For example, if traffic intensifies, a passenger may stop talking to allow the driver to navigate the increasingly difficult roadway; a conversation partner over a phone would not be aware of the change in environment. There have been multiple theories regarding divided attention. One, conceived by Kahneman , [24] explains that there is a single pool of attentional resources that can be freely divided among multiple tasks.

This model seems to be too oversimplified, however, due to the different modalities e. The specific modality model was theorized by Navon and Gopher in However, more recent research using well controlled dual-task paradigms points at the importance of tasks. In contrast, when one of the tasks involves object detection, no interference is observed.

As an alternative, resource theory has been proposed as a more accurate metaphor for explaining divided attention on complex tasks. Resource theory states that as each complex task is automatized, performing that task requires less of the individual's limited-capacity attentional resources. These include, but are not limited to, anxiety, arousal, task difficulty, and skills. Simultaneous attention is a type of attention, classified by attending to multiple events at the same time. Simultaneous attention is demonstrated by children in Indigenous communities, who learn through this type of attention to their surroundings.

Simultaneous attention requires focus on multiple simultaneous activities or occurrences. This differs from multitasking, which is characterized by alternating attention and focus between multiple activities, or halting one activity before switching to the next.

1. Functional domains of mind and brain: a brief historical sketch and the issue of integration

Simultaneous attention involves uninterrupted attention to several activities occurring at the same time. Another cultural practice that may relate to simultaneous attention strategies is coordination within a group. Indigenous heritage toddlers and caregivers in San Pedro were observed to frequently coordinate their activities with other members of a group in ways parallel to a model of simultaneous attention, whereas middle-class European-descent families in the U.

Attention may be differentiated into "overt" versus "covert" orienting. Overt orienting is the act of selectively attending to an item or location over others by moving the eyes to point in that direction. Although overt eye movements are quite common, there is a distinction that can be made between two types of eye movements; reflexive and controlled. Reflexive movements are commanded by the superior colliculus of the midbrain.

These movements are fast and are activated by the sudden appearance of stimuli. In contrast, controlled eye movements are commanded by areas in the frontal lobe. These movements are slow and voluntary. Covert orienting is the act to mentally shifting one's focus without moving one's eyes. Covert orienting has the potential to affect the output of perceptual processes by governing attention to particular items or locations for example, the activity of a V4 neuron whose receptive field lies on an attended stimuli will be enhanced by covert attention [36] but does not influence the information that is processed by the senses.

Researchers often use "filtering" tasks to study the role of covert attention of selecting information. These tasks often require participants to observe a number of stimuli, but attend to only one. The current view is that visual covert attention is a mechanism for quickly scanning the field of view for interesting locations. This shift in covert attention is linked to eye movement circuitry that sets up a slower saccade to that location.

There are studies that suggest the mechanisms of overt and covert orienting may not be controlled separately and independently as previously believed. Central mechanisms that may control covert orienting, such as the parietal lobe, also receive input from subcortical centres involved in overt orienting. Orienting attention is vital and can be controlled through external exogenous or internal endogenous processes.

However, comparing these two processes is challenging because external signals do not operate completely exogenously, but will only summon attention and eye movements if they are important to the subject. Exogenous from Greek exo , meaning "outside", and genein , meaning "to produce" orienting is frequently described as being under control of a stimulus. This often results in a reflexive saccade. Since exogenous cues are typically presented in the periphery, they are referred to as peripheral cues. Exogenous orienting can even be observed when individuals are aware that the cue will not relay reliable, accurate information about where a target is going to occur.

This means that the mere presence of an exogenous cue will affect the response to other stimuli that are subsequently presented in the cue's previous location. Several studies have investigated the influence of valid and invalid cues. Posner and Cohen noted a reversal of this benefit takes place when the interval between the onset of the cue and the onset of the target is longer than about ms.

Endogenous from Greek endo , meaning "within" or "internally" orienting is the intentional allocation of attentional resources to a predetermined location or space. Simply stated, endogenous orienting occurs when attention is oriented according to an observer's goals or desires, allowing the focus of attention to be manipulated by the demands of a task.

In order to have an effect, endogenous cues must be processed by the observer and acted upon purposefully. These cues are frequently referred to as central cues. This is because they are typically presented at the center of a display, where an observer's eyes are likely to be fixated. Central cues, such as an arrow or digit presented at fixation, tell observers to attend to a specific location.

When examining differences between exogenous and endogenous orienting, some researchers suggest that there are four differences between the two kinds of cues:. There exist both overlaps and differences in the areas of the brain that are responsible for endogenous and exogenous orientating. Researchers of this school have described two different aspects of how the mind focuses attention to items present in the environment. The first aspect is called bottom-up processing, also known as stimulus-driven attention or exogenous attention. These describe attentional processing which is driven by the properties of the objects themselves.

Some processes, such as motion or a sudden loud noise, can attract our attention in a pre-conscious, or non-volitional way. We attend to them whether we want to or not. The second aspect is called top-down processing, also known as goal-driven, endogenous attention, attentional control or executive attention. This aspect of our attentional orienting is under the control of the person who is attending. It is mediated primarily by the frontal cortex and basal ganglia [48] [49] as one of the executive functions.

Studies show that if there are many stimuli present especially if they are task-related , it is much easier to ignore the non-task related stimuli, but if there are few stimuli the mind will perceive the irrelevant stimuli as well as the relevant. The cognitive refers to the actual processing of the stimuli. Studies regarding this showed that the ability to process stimuli decreased with age, meaning that younger people were able to perceive more stimuli and fully process them, but were likely to process both relevant and irrelevant information, while older people could process fewer stimuli, but usually processed only relevant information.

Some people can process multiple stimuli, e. Attention is best described as the sustained focus of cognitive resources on information while filtering or ignoring extraneous information. As is frequently the case, clinical models of attention differ from investigation models. One of the most used models for the evaluation of attention in patients with very different neurologic pathologies is the model of Sohlberg and Mateer.

Five different kinds of activities of growing difficulty are described in the model; connecting with the activities those patients could do as their recovering process advanced. This model has been shown to be very useful in evaluating attention in very different pathologies, correlates strongly with daily difficulties and is especially helpful in designing stimulation programs such as attention process training, a rehabilitation program for neurological patients of the same authors. Most experiments show that one neural correlate of attention is enhanced firing.

If a neuron has a certain response to a stimulus when the animal is not attending to the stimulus, then when the animal does attend to the stimulus, the neuron's response will be enhanced even if the physical characteristics of the stimulus remain the same. In a review, Knudsen [57] describes a more general model which identifies four core processes of attention, with working memory at the center:.

Neurally, at different hierarchical levels spatial maps can enhance or inhibit activity in sensory areas, and induce orienting behaviors like eye movement. In many cases attention produces changes in the EEG. Another commonly used model for the attention system has been put forth by researchers such as Michael Posner. He divides attention into three functional components: Children appear to develop patterns of attention related to the cultural practices of their families, communities, and the institutions in which they participate. In , Jules Henry suggested that there are societal differences in sensitivity to signals from many ongoing sources that call for the awareness of several levels of attention simultaneously.

He tied his speculation to ethnographic observations of communities in which children are involved in a complex social community with multiple relationships. Many Indigenous children in the Americas predominantly learn by observing and pitching in. There are several studies to support that the use of keen attention towards learning is much more common in Indigenous Communities of North and Central America than in a middle-class European-American setting.

Keen attention is both a requirement and result of learning by observing and pitching-in. Incorporating the children in the community gives them the opportunity to keenly observe and contribute to activities that were not directed towards them. It can be seen from different Indigenous communities and cultures, such as the Mayans of San Pedro , that children can simultaneously attend to multiple events. One example is simultaneous attention which involves uninterrupted attention to several activities occurring at the same time.

San Pedro toddlers and caregivers frequently coordinated their activities with other members of a group in multiway engagements rather than in a dyadic fashion. This learning by observing and pitching-in model requires active levels of attention management. The child is present while caretakers engage in daily activities and responsibilities such as: Eventually the child is expected to be able to perform these skills themselves. In the domain of computer vision , efforts have been made to model the mechanism of human attention, especially the bottom-up intentional mechanism [74] and its semantic significance in classification of video contents [75] [76].

Both spatial attention and temporal attention have been incorporated in such classification efforts. Generally speaking, there are two kinds of models to mimic the bottom-up salience mechanism in static images. One way is based on the spatial contrast analysis. For example, a center—surround mechanism has been used to define salience across scales, inspired by the putative neural mechanism.

1. Introduction

This model has established itself as the exemplar for salience detection and consistently used for comparison in the literature; [74] the other way is based on the frequency domain analysis. This method was first proposed by Hou et al. Hemispatial neglect, also called unilateral neglect , often occurs when people have damage to their right hemisphere. Damage to the left side of the brain the left hemisphere rarely yields significant neglect of the right side of the body or object in the person's local environments. The effects of spatial neglect, however, may vary and differ depending on what area of the brain was damaged.

Damage to different neural substrates can result in different types of neglect. Attention disorders lateralized and nonlaterized may also contribute to the symptoms and effects. New technology has yielded more information, such that there is a large, distributed network of frontal, parietal, temporal, and subcortical brain areas that have been tied to neglect. Social attention is one special form of attention that involves the allocation of limited processing resources in a social context.

Previous studies on social attention often regard how attention is directed toward socially relevant stimuli such as faces and gaze directions of other individuals. In one extreme, individual tends to attend to the self and prioritize self-related information over others', and, in the other extreme, attention is allocated to other individuals to infer their intentions and desires.

Attending-to-self and attending-to-others mark the two ends of an otherwise continuum spectrum of social attention. For a given behavioral context, the mechanisms underlying these two polarities might interact and compete with each other in order to determine a saliency map of social attention that guides our behaviors. Berlyne credits the first extended treatment of attention to philosopher Nicolas Malebranche in his work "The Search After Truth". Otherwise we will confuse these ideas. Malebranche writes in "The Search After Truth", "because it often happens that the understanding has only confused and imperfect perceptions of things, it is truly a cause of our errors It is therefore necessary to look for means to keep our perceptions from being confused and imperfect.

And, because, as everyone knows, there is nothing that makes them clearer and more distinct than attentiveness, we must try to find the means to become more attentive than we are". Philosopher Gottfried Wilhelm Leibniz introduced the concept of apperception to this philosophical approach to attention.

School of Psychology

Apperception refers to "the process by which new experience is assimilated to and transformed by the residuum of past experience of an individual to form a new whole. Leibniz emphasized a reflexive involuntary view of attention known as exogenous orienting. However, there is also endogenous orienting which is voluntary and directed attention. Philosopher Johann Friedrich Herbart agreed with Leibniz's view of apperception; however, he expounded on it in by saying that new experiences had to be tied to ones already existing in the mind.

Herbart was also the first person to stress the importance of applying mathematical modeling to the study of psychology. In the beginning of the 19th century, it was thought that people were not able to attend to more than one stimulus at a time. However, with research contributions by Sir William Hamilton, 9th Baronet this view was changed.

Hamilton proposed a view of attention that likened its capacity to holding marbles. You can only hold a certain amount of marbles at a time before it starts to spill over. His view states that we can attend to more than one stimulus at once. William Stanley Jevons later expanded this view and stated that we can attend to up to four items at a time. During this period of attention, various philosophers made significant contributions to the field. They began the research on the extent of attention and how attention is directed. This period of attention research took the focus from conceptual findings to experimental testing.

It also involved psychophysical methods that allowed measurement of the relation between physical stimulus properties and the psychological perceptions of them. This period covers the development of attentional research from the founding of psychology to Wilhelm Wundt introduced the study of attention to the field of psychology. Wundt measured mental processing speed by likening it to differences in stargazing measurements.

Astronomers in this time would measure the time it took for stars to travel. Among these measurements when astronomers recorded the times, there were personal differences in calculation. These different readings resulted in different reports from each astronomer. To correct for this, a personal equation was developed. Wundt applied this to mental processing speed. Wundt realized that the time it takes to see the stimulus of the star and write down the time was being called an "observation error" but actually was the time it takes to switch voluntarily one's attention from one stimulus to another.

Wundt called his school of psychology voluntarism. It was his belief that psychological processes can only be understood in terms of goals and consequences. Franciscus Donders used mental chronometry to study attention and it was considered a major field of intellectual inquiry by authors such as Sigmund Freud.

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