To find out, they took attention out of the equation by presenting the fearful or neutral face in the same quadrant as the subsequent target grating would appear instead of in the middle of the screen as in Experiment 1.
But again, exposure to a fearful face increased contrast sensitivity, even though attentional shifts were no longer involved.
The authors proposed that this effect is probably the result of feedback from the amygdala, to the early visual cortex, as well as to regions that enhance attention. The amygdala responds to significant stimuli, including fearful faces, rapidly and prior to awareness. A fearful face indicates that there may be a threat in the environment, but it gives no information as to its form or location, so enhanced contrast sensitivity might aid in detecting the threat [ 10 ].
Other research shows that high-level goals can also influence the responsivity of the amygdala to affective stimuli. The amygdala is believed to respond to affective stimuli more or less automatically, but evidence shows that responses depend on the current relevance of affective stimuli [ 11 ]. In an imaging study, participants were asked to rate either the positive or negative aspects of 96 famous names Adolph Hitler, Paris Hilton, Mother Theresa, George Clooney. The results showed that when evaluating positive aspects, the amygdala responded only to the names of people that a given participant liked, and when evaluating negative aspects, the amygdala responded only to the names of disliked people.
Thus, the automatic affective reactions of the amygdala were guided by the current goal of the individual. It is unclear whether the amygdala itself filtered information for motivational significance or whether top down processes did so before information reached the amygdala. But the results encourage a view of the brain in which high- and low-level processes continually interact—a view within which it becomes less surprising that emotion can affect perception.
Some conditions encourage global perception and some encourage local perception, but people generally show a tendency to process globally. This is apparently not true of autistic individuals [ 12 ] or of individuals in certain cultures [ 13 ] who more readily see local details.
Emotion also influences whether people focus on the forest or the trees. After hitting his head during a parachute jump, the psychologist Easterbrook [ 14 ] noted that his spatio-temporal field seemed to shrink [ 15 ]. With this experience in mind, he later proposed that stress narrows atttention. Fifty years later, many findings support this idea as well as the extension that positive emotion broadens attention [ 16 , 17 ].
Relevant research sometimes employs standard tests to measure global and local perception. On the Kimchi test, respondents are shown a target geometric figure and asked which of two comparison figures is most similar to it [ 18 ].
As shown in Figure 2 , the target might be three small squares arranged in the overall shape of a triangle. People then choose which of two comparison figures is most similar. One comparison figure is a triangle composed of small triangles, and the other is a square composed of small squares. A local response would be to choose the figure with squares, because the target figure had been composed of squares. A global response would to choose the figure with triangles, because the overall shape of the target figure had been a triangle.
When investigators induce happy or sad moods for example, by having participants spend a few minutes writing about a happy or sad event from their lives , participants in happy moods often adopt a global perceptual style, whereas those in sad moods adopt a local perceptual style [ 19 ].
The task is to match the target figure at the top with the comparison figure at the bottom that is most similar. Another standard method, the Navon procedure, involves measuring reaction times to large or small letters [ 20 ].
Comparing the reaction times to detect letters appearing as global stimuli and those appearing as local stimuli yields a measure of whether global or local perceptual styles are dominant. Some research using this measure suggests that although global processing occurs in generic positive moods, states in which a specific object elicits approach motivation e.
Still other research suggests that rather than a dedicated relationship between affect and perceptual style, positive affect may facilitate and negative affect may inhibit whatever orientation is most accessible in a given situation. A test of that hypothesis used cognitive priming techniques to alter whether a global or a local orientation was momentarily more accessible [ 22 ].
The results showed that when local responding was made especially accessible, the usual result was reversed. Positive affect then led to a focus on details and sad moods to a focus on the big picture.
It appears, therefore, that positive affect may facilitate whatever the dominant orientation is rather than being specifically tied to a global focus. However, rather than reflecting a direct connection to perception, these data indicate that positive affect can empower and negative affect can inhibit either a big or a small view, depending on which is dominant in a given situation.
The tendency for negative affect to lead to a local perceptual style is also evident in research on visual illusions.
For example, the Ebbinghaus illusion see Figure 3 involves a visual contrast effect in which the same target circle appears smaller when surrounded by big circles and bigger when surrounded by small circles.
The illusion is very compelling, but recent research shows that sad moods reliably reduce the effect [ 23 ]. In the same research, sad moods were found to reduce context effects and increase the accuracy of judgments of the temperature of lukewarm water after exposure to hot or cold water and of the weight of a one kg box after lifting a heavier box.
The Ebbinghaus Illusion. The circles in the middle of these two figures are the same size, but in their respective contexts, the one on the left looks smaller than the one on the right. A similar tendency for sad mood to lead to the exclusion of contextual stimuli is evident in studies of semantic priming [ 24 ]. Whereas people are usually slightly faster to identify words after a brief exposure to a word similar compared to dissimilar in meaning, this does not occur for individuals in induced sad moods, even though such mild states do not slow responding overall.
This phenomenon is interesting in the current context because it suggests that emotional factors may have similar effects on perceptual and conceptual processes. Explanations have stressed that sad moods interfere with the usual relational processing processing incoming information in relation to current mental context , leading to item-specific or referential processing [ 24 ]. That explanation is also compatible with the idea that negative affect narrows attention [ 15 , 16 ].
The studies we have reviewed show that emotional and motivational factors can regulate global vs. But, as noted above, the same is also true when the stimuli are conceptual rather than sensory. For example, individuals feeling happy are more likely to use stereotypes and other categorical information when forming impressions of others. By contrast, when forming impressions, people feeling sad focus on behavioral or other detailed information and tend not to use global categories [e.
Such results may indicate that the influences of affect on global-local perception and conception are mediated by attention. Attention is sometimes thought of as a spotlight that directs limited processing resources to the most relevant stimuli [ 28 , 29 ].
If affect signals value [ 30 ] or motivational significance [ 31 ], then we might expect affect to influence attention.
For example, activating an affective attitude leads to attitude-consistent judgments [ 32 ] by biasing attention toward attitude-relevant stimuli [ 33 ]. Studies examining the role of emotion in attention have sometimes employed a spatial probe task for measuring attention. In the spatial probe task, two words are presented briefly in different locations followed by a dot probe in one of the locations.
If an emotion-relevant word attracts attention, the dot appearing in that location will be detected faster than a dot appearing in the other location. Speed of response to the dot is thus a useful measure of selective attention [ 32 ].
Some of the research using this technique has been conducted by clinical psychologists interested in the effects of anxiety. The general finding is that fear and anxiety bias attention toward threatening stimuli, including words and pictures [e.
Selective attention may thus serve to facilitate the processing of threat information [ 28 ]. Positive affective reactions signal opportunities rather than dangers, raising the question of whether positive affect also directs attention. Indeed, evidence from dot probe studies indicates that positive moods bias attention toward positively valued stimuli [ 37 ].
As a result, positive affect should make rewards easier to detect, just as anxiety facilitates threat detection. Of course, attending to the upside, rather than the down-side, of events is also likely to elevate mood and subjective well-being. Traditionally, the study of perception has stressed low level, bottom-up visual processes. But research suggests that higher level processes may play a role as well. A recent study demonstrated top-down effects of emotional information on face perception [ 38 ].
The study involved a binocular rivalry task, in which a different image is presented to each eye—for instance, a face and a house. In that task, only one image is consciously experienced at a time, and which image is seen tends to alternate every few seconds. The images essentially compete for dominance, the more important or relevant image being perceived relatively longer. In this experiment, faces became more dominant in the rivalry task after being paired with descriptions of negative social information, such as, that the person lied, stole, or cheated.
The results suggest that gossip and other social information may tune the visual system, aiding in the detection of persons who should be avoided without requiring any direct negative experience with them.
This idea that the emotional significance of objects may make them easier to see has a long and interesting research history, as we see next. For example, Bruner and Goodman [ 39 ] reported an experiment in which a sample of poor children from the Boston slums perceived coins to be larger than did children from wealthier Boston families.
The same effect did not appear for similarly-sized cardboard disks, leading the authors to conclude that motivation can influence perceptions of size, making motivationally-relevant objects easier to see. At the time, the idea that visual perception, our window to objective reality, might be guided by subjective desires was seen as quite unacceptable.
Moreover, when the New Look was elaborated to include predictions from Freudian theory, it was soundly rejected by many investigators. But the basic hypothesis that motivation might affect perception has since been revisited.
Recent evidence shows that, for example, people who are thirsty perceive a glass of water as taller than those who are not thirsty [ 5 ]. And when typically neutral goals, such as gardening, are made positive by pairing them with positive stimuli, tools associated with the goal such as a shovel appear larger [ 5 ].
Similarly, smokers deprived of cigarettes tend to overestimate the length of a standard cigarette [ 40 ]. Other findings also indicate that ambiguity in visual stimuli e. In related research, participants who had agreed to walk on their campus wearing a large, embarrassing sign underestimated the distance to be walked [ 42 ]. The authors reasoned that the misperception of distance was a way of reducing the cognitive dissonance of having freely chosen to engage in such an unpleasant action.
Consistent with the original New Look logic, such data again suggest that goals can tune the visual system to see the world in motivationally-consistent ways [for more on the social psychology of perception, see 43 ]. Whereas most of the emotional effects we have discussed have been evident only in limited, somewhat artificial laboratory settings, this experiment and the research to be discussed in the remainder of this review concern perception in the world.
Emotional effects in real-world environments may be more pervasive than most people realize. It is often assumed that one of the primary goals of the visual system is to recreate the environment, forming a representation in the brain that is as accurate as possible. However, research over the past ten or fifteen years has demonstrated that this is not the case.
Rather than reproducing pictures inside the brain, research results indicate that what we perceive is a systematically altered version of reality.
A child with visual figure-ground discrimination may struggle to pick out numbers or words from a page. Recalling something the child saw recently. A child with visual memory problems may struggle to recall a written phone number or how a word is spelled.
Distinguishing the order of numbers, letters, words, or images. Problems with visual sequencing may cause a child to struggle with filling in the bubbles on a test, aligning numbers for addition or subtraction, or keeping their place when reading a page.
A child with visual-spatial processing issues may struggle with judging time, reading a map, understanding written instructions, etc. Using the eyes to coordinate body movements. Children with visual- motor processing may be unable to copy word or judge the distance of an object.
After the visual stimulus leaves the eyes, it is first processed through distinct points in the brain known as lateral geniculate bodies along the path to the occipital lobes. Then, that information exits the occipital lobes in white matter tract pathways called streams to other parts of the brain.
In other words, the brain is figuring out what to do with the visual information it has received; how to use it to recognize persons seen before; map routes; recognize symbols and letters; and many other interpretations.
Think about your overall design and also your individual design elements and think about what their purpose is. You probably want your logo to be remembered and recognized. You likely want your content to be understood.
In order to create successful designs we must think about the cognitive tasks of our visitors. We must also think about the visual queries our designs and graphics aim to support. This post has tried to give you an overview of how we all perceive things visually.
From the bottom-up we see a series of small details that work their way into and modify our prior understanding of the visual environment. From the top-down we hold preconceived ideas of the visual environment around us that direct where we look and interpret what we see. Visual perception happens quickly, but a very complex set of interactions occurs in a short time span in order for it to happen.
By understanding how this process works we can make choices to direct the eye and have our visitors attach meaning to our visual elements enabling them to better remember and understand our message.
Download a free sample from my book, Design Fundamentals. In the Top Down processing, do you suggest to use colors and sizes of letters like colored word clouds? Without reading the theory I made some similar text in one of my website www.
Perhaps I should do it again…. What do they want to do on the page? Why kind of schemas and mental models do they hold about the world. A simple example might be a site designed for a young, high tech, male audience. That audience might prefer small white text on a dark background. Compare that to a site designed for senior citizens with poor eyesight.
Great post! Great read! Understanding the science of design is equally as important as understanding the execution. Thanks Kevin. As you can tell I agree about the science. I am a Human Factors masters student and this article perfectly described what I plan to study. So helpful and well written.
I also purchased the book you requested. Thanks for the post! If you liked this post I think you will like the book. I am very glad to have stumbled upon this article! I am both a graphic design and psychology major and am currently taking a class on perception science. I realize that a lot of what I learn in that class is relatable to design, and this article really captured it well! Thanks for the post. I am constantly surprised that visual cognition, how humans look and absorb information, is not included in all graphic arts courses.
Thanks again. Your email address will not be published. However, how the visual system determines object orientation in three-dimensional 3D space is less understood.
How accurately does the visual system perceive object orientation? In principle, 3D orientation estimation from a 2D retinal image is an ill-posed problem e. Therefore, it is not surprising that perceived object depth orientation is imprecise. Several studies have demonstrated that the perception of oblique object orientation e. First, visual sensitivity to object orientation differences is lower for oblique orientations than for cardinal orientations front, profile for everyday objects [2] and human heads [3].
This is akin to the oblique effect in the perception of line orientation on the front parallel plane [4] , [5]. Second, perception of object orientation deviates systematically from physical orientation. In Niimi and Yokosawa's study [6] , participants observed object images presented on a computer screen and estimated the objects' orientation in depth i. Their results showed that oblique orientations yielded significant perceptual biases toward the profile view.
Similar biases have also been reported for the slant estimation of simple 3D objects [7] — [9]. One possible explanation for the bias in oblique orientation estimation is the low visual similarity between frontal views and three-quarter views, as it is well known that the frontal orientation often yields accidental and unfamiliar views [10] , [11].
Orientation judgment requires a processing reference frame, usually the egocentric reference frame. Previous studies have tested the perception of object orientation based on the egocentric reference frame i. However, in daily visual experiences we observe objects embedded in visual scenes, which contain rich spatial information—including global or allocentric reference frames. It is known that a scenic background is automatically processed during visual object perception [12] , [13].
Global reference frames may influence the perception of object orientation in two ways. First, global reference frames provide rich spatial information and may improve depth perception.
If biases in oblique orientation perception when objects are presented on blank backgrounds are partly due to a lack of global reference frames, then object orientation perception may be more precise when an appropriate global reference frame is provided. Alternatively, global reference frames may induce a contextual effect that biases or distorts object orientation perception. Many studies have demonstrated that contextual stimuli such as background scene play the role of a global reference frame, and bias human performance on spatial tasks related to orientation.
For example, surrounding stimuli alter orientation judgments of 2D shapes [14] , [15]. Perception of slant defined by binocular disparity is affected by flanking contextual surfaces [16]. Visual backgrounds e. Memories of spatial layout are organized in terms of global reference frames [20] — [22]. Moreover, it was shown that task performance related to perception of depth orientation was biased when the room orientation was not aligned with participants' gaze line [23] , [24].
Although the experimental tasks in these studies parallelity judgments or pointing did not measure perceived object orientation directly, the results led us to hypothesize that a global reference frame may influence the perception of object orientation in 3D space.
The current study examined the effect of a background scene that suggests a global reference frame e. Although the actual environment does not always provide such salient reference frame e. We asked participants to evaluate object orientation while manipulating the background images. The first goal was to contrast orientation judgments of objects presented with a scene and those presented without a scene i. For example, the presence of an apparent global reference frame that is aligned with participants' gaze lines might improve depth perception and thus reduce bias in judgments of oblique orientations.
Second, we varied the axis orientation of the scene and examined whether an oblique scene axis would produce a contextual effect, and thus bias perception of object orientation. In Experiment 1, participants viewed objects presented on a computer screen and evaluated their depth orientation i. We measured estimated object orientations and their deviations from the true object orientations when 1 the scene was absent blank background , 2 the scene was present and its orientation was aligned with the gaze line, and 3 the scene was present but misaligned with the gaze line.
We used scene stimuli with dominant structures street, building, wall that regulated orientation of other objects in the scene. The dominant structures provided the principal axis as a global reference frame, and then, we defined scene orientation as the orientation of the axis.
Nineteen individuals 13 female, 6 male; mean age They all reported normal or corrected-to-normal visual acuity. Stimuli were colored images generated by 3D graphic software Shade 9, e-frontier Inc. Cast shadows were not rendered. We adopted a 3D model data of 24 common objects 18 for experimental trials and 6 for practice trials , which have been used in previous studies [2] , [6]. All the objects had clear frontal orientations and upright positions.
Objects with a thin or elongated shape e. We included six wide objects e. See Figure S1 for the entire list. We prepared six scenes three indoor and three outdoor that had obvious global reference frame axes see Figure 1B. These scenes were constructed by assembling 3D models of objects available in commercial datasets. We put a round table in front of the viewpoint and placed the target object on the table Figure 1A ; the objects and the scene were rendered into stimulus images.
The position of the table relative to the viewpoint was fixed. As seen in Figure 1 , the scene's depth is defined predominantly by the perspective and the perspective does not represent the principal characteristic of the depth for the object's orientation. However, the semantic consistency of object and scene was not controlled e. Six scenes shown in gaze-aligned orientations. All stimulus images were presented in color during the experiment.
The objects and scenes were rotated about the vertical axis to manipulate depth orientation. The axis of rotation was along the center of the table. Participants observed the stimulus images presented on a computer screen in CRT , binocularly.
No stereoscopic device was used. Consequently, we studied the effect of pictorial depth information on the perception of object orientation in the same manner as in our previous studies [2] , [6].
However, it should be noted that a binocular disparity might reduce bias in 3D orientation perception [25]. If an observer views a perspective picture from a viewpoint that deviates from the viewpoint from which the picture was taken, the perceived 3D space may be distorted [9] , [26] — [29].
The participants' gaze line was roughly directed to the center of the screen. The stimulus images subtended This field of view was the replication of the virtual camera. The horizontal field of view was roughly matched to that of a mm focal length for a mm film.
Another screen, the response display, was located horizontally in front of the participants Figure 2. Participants were asked to adjust the orientation of a dark disk on the response display response disk so that it matched the orientation of the object. A white dot on the edge of the response disk marked the front of the disk.
A mouse cursor was displayed as a black dot, and participants used the mouse to rotate the response disk by clicking and dragging. No participant reported difficulty in using the response display after completing practice trials.
Participants rotated the disk on the horizontal response display so that the disk orientation matched the perceived depth orientation of the object. On the response display, a white dot indicated the frontal orientation of the response disk.
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