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The concept of visual competence as seen from theperspective of the psychological and brain sciencesArvid Kappas & Bettina OlkPublished online: 21 Aug 2008.

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The concept of visual competence as seen from theperspective of the psychological and brain sciences

ARVID KAPPAS AND BETTINA OLK

Visual competence in its most basic form relates to

fundamental processes of visual perception. The analysis of

neuropsychological impairments and recent advances in

the brain sciences have led to considerable changes in how

vision is understood in recent years. In this sense, vision is

a mix of general and specific processes (e.g. face perception,

motion perception). It is influenced by personal experience

and thus cultural influences within the given biological

constraints. Furthermore, there is evidence for an early

interaction of vision with other perceptual modalities,

particularly sound. The recent discovery of a neural

‘mirror system’ suggests a strong coupling between

perception and action. Visual exploration is driven by

volitional and automatic processes. The authors argue that

applied concepts of visual competence are likely to benefit

from considering basic research in the psychological and

brain sciences.

Whether we are watching a soap opera, browsing

through a catalogue, admiring a sculpture at an

exhibition or glancing at the face of a colleague for

signs of approval, a complex set of processes in our

brain related to vision is involved in making sense of

the stream of information that our eyes provide. Vision

is a highly complex interaction with our environment

that relies on learned information and is shaped by

biological constraints of our brain. The importance of

vision is reflected by the fact that over half of our

cortex is involved in visual processing in one way or

another.

Vision is closely linked with other sense information.

For example, upon entering a train station, visual

information is integrated with sounds and smells. Even

the feeling of concrete under our feet, or the cold air that

brushes against our face, become part of a holistic

perception of a situation or place that allows us to act

and pursue our goals, such as finding a particular

platform to continue our journey.

We are used to considering the world as a stationary

entity through which objects move and in which we

move as well. In reality, there is nothing stationary about

the information our eyes provide to the brain. Our eyes

tend to fixate only very briefly – typically fractions of a

second – on objects or locations in space and then tend

to move on. These jumps from fixation point to fixation

point are called saccades. In consequence, our subjective

experience of the world and of objects in there involves a

lot of processing by our brains. The outcome of this

processing is shaped by biological and environmental

factors. Understanding the complexity of this process is

useful and perhaps even necessary for the development

of a concept such as visual competence.

It is important, in the context of this special issue, to

underline that perceiving mediated visuals or other

forms of visual communication recruits a variety of

more general processes, including various types of

knowledge and expertise. The present contribution is an

attempt to give a very brief overview over the complexity

of vision. We try to highlight that an understanding of

visual competence involves both fundamental and

domain-specific processes that are studied in the

psychological and brain sciences. In particular, we would

like to argue that visual competence is not static but can

change. In the following we will provide examples of

how it can increase (e.g. with gaining expertise), and

decrease (e.g. due to injuries). Applications of basic

psychological research will be briefly discussed.

THE COMPLEXITY OF SEEING AND PERCEIVING

Our visual world is undoubtedly very complex. It is

filled with moving or stationary objects that differ in

shape, size, colour, brightness and texture. Rays of light

travel through our eyes and it is those flat patches of

light on the retina that eventually have to be detected as

objects or people in the world. To make this possible,

Bettina Olk is Assistant Professor of Psychology at Jacobs University Bremen, Germany. Current projects, funded by the Royal Society and the German Academic

Exchange Service, investigate the integration of reflexive and volitional visual attention and eye movements, and the control of reaching behaviour and eye

movements in healthy persons as well as patients with visual attention deficits following brain injuries. Further studies examine brain mechanisms underlying the

control of visual attention using Transcranial Magnetic Stimulation (TMS).

Arvid Kappas is Professor of Psychology at Jacobs University Bremen, Germany. His work focuses on what causes/modulates physiological and expressive

reactions associated with emotions as well as interpersonal affective processes, such as nonverbal communication. He is associate editor of the journals Biological

Psychology and Emotion, member of the editorial boards of Cognition and Emotion, Journal of Nonverbal Behavior and British Journal of Social Psychology, and has

authored numerous articles and chapters on human emotions.

Visual Studies, Vol. 23, No. 2, September 2008

ISSN 1472–586X printed/ISSN 1472–5878 online/08/020162-12 # 2008 International Visual Sociology Association

DOI: 10.1080/14725860802276313

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the visual information makes its journey via the visual

pathways through the brain, undergoing several stages of

processing.

Basic research has discovered that our visual system is an

expert at detecting features such as colour, brightness,

orientation, length and curvature of visual stimuli, and to

group what belongs together. In the early twentieth

century, the Gestalt psychologists (e.g. Wertheimer,

Koffka, Kohler; see Sahakian 1968) investigated how parts

are organised into a ‘whole’, the ‘Gestalt’. Their laws of

perception include, among others, that if elements are

close to one another (‘law of proximity’), are similar (‘law

of similarity’) or follow in the same direction (‘law of

good continuation’), we tend to perceive them as

belonging together (see Coren, Ward, and Enns 1999).

And importantly, our knowledge of the world needs to be

combined with what we see to give it meaning. Seeing an

object that consists of, say, a long line with a narrow

rectangle at one end, made up of many short lines, is not

sufficient to recognise it as a toothbrush and to know

what it is used for. This small example illustrates that

perceiving is not a one-way road and that it is more than

the projection of the outside world onto the retina of the

eye and the transfer of information via visual pathways to

visual areas in the brain. Our knowledge and our

expectations influence what we perceive. Perception is in

fact a very active endeavour. Psychological research on

perception is interested in how our visual system

processes ‘stimuli’ and how the brain integrates visual

information with input from the other senses, such as

auditory, tactile, somatosensory and olfactory, and allows

the organism to respond with appropriate behaviour. The

psychology of perception thus seeks to understand how

the human visual system and brain tackles the non-trivial

challenge of perception.

Similarly, imagining an object recruits areas of the brain

that are involved in seeing (e.g. Kosslyn et al. 1995).

Kosslyn and his colleagues argue that ‘visual mental

imagery involves ‘‘depictive’’ representations, not solely

language-like descriptions’ (496). In other words, the

relationship between perceiving and thinking is a two-

way road. Typically, one requires the other. More recent

evidence suggests that such findings can provide

objective means of measuring the vividness of mental

imagery even in the absence of people reporting their

subjective experience (Cui et al. 2007)!

EXPLORING OUR VISUAL WORLD

In order to interact with our stimulus-rich world, it is

imperative that we explore it and orient towards sources

of information in our environment. On the one hand,

our attention is attracted by suddenly appearing, visually

salient and new stimuli (e.g. Theeuwes et al. 1998). On

the other hand, we are able to disregard unimportant

pieces of information and direct our attention in a

controlled, goal-directed manner to relevant

information (Yarbus 1967; Serences and Yantis 2006).

That both ways of orienting affect where (or to what) we

attend, and that in fact a selection is crucial, is illustrated

by the following example. When driving on a busy city

street, our goal will be to focus on the road ahead while

many potentially distracting events will be present in the

periphery. Some of those peripheral events, such as

advertisements or people walking on the pavement, may

be largely disregarded, but others are attended to

because they are of importance and relevant for the

required driving behaviour (e.g. hitting the brake for a

pedestrian who is suddenly starting crossing the street or

looking at a sign that indicates where we need to turn).

Selection is important because allowing our attention

and our eyes to wander to each peripheral event and to

dwell on them would surely result in an accident. The

example thus illustrates the link between attending,

understanding a situation and behaving appropriately.

A very fast way of exploring our visual world is to move

our eyes. Moving our eyes is a behaviour that we engage

in more than 170,000 times each day, making about

three saccadic eye movements each second. The function

of the saccades is to bring areas of interest into our

fovea, the part of our retina where we can see with the

highest spatial resolution. Because the acuity of vision

decreases outside the fovea, making eye movements is

essential. And as we can only fixate one small area at a

time and move our eyes in one direction at a time, our

brain needs to decide where the eyes should be moved to

and for how long they should dwell on a given area. Eye

movement research is thus concerned with investigating

which factors are considered by the brain in this decision

process and which brain areas are involved.

An elegant way to learn about visual exploration is to

record the rapid sequences of saccades and fixations and

to determine where saccades are directed and for how

long a given area is looked at under different

experimental conditions. Technological developments of

modern eye-tracking equipment allow the recording of

such information in great temporal and spatial detail.

Modern eye trackers are able to record the fixation

location of the eyes up to twice every millisecond! There

are different types of eye-tracking devices on the market.

Some consist of headsets with small cameras attached to

them that are placed on the head of the participants;

Visual competence 163

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others are positioned on the table some 30 cm away

from the eyes of the participant (remote eye trackers),

while participants sit at a table and view visual stimuli

on a computer monitor. Mobile systems allow the

participant to move around, usually wearing on their

head the eye tracker and a camera that records the

environment, and further necessary equipment in a

backpack. The obtained data provide objective

measurements from which the scanpath can be

reconstructed. It can be inferred, for example where,

when and for how long someone looked at a certain

location. An example is given in Figure 1. The data are

also available in numeric format, allowing statistical

analyses.

Neurophysiological and neuropsychological studies

have contributed much knowledge about the network

of brain areas involved in the generation of eye

movements and how these brain areas work. Cells

that are active when we fixate and cells that are active

when we move our eyes have been identified. The

network of brain areas consists of structures lying

under the cortex (subcortical), such as the superior

colliculus (SC), basal ganglia and brain stem, cortical

areas in the front of the brain such as the frontal eye

field (FEF), the supplementary eye field (SEF) and

the dorsolateral prefrontal cortex (dlPFC), and areas

located more towards the back of the brain, such as

the parietal eye field (Schiller 1984; Guitton, Buchtel,

and Douglas 1985; Henik, Rafal, and Rhodes 1994;

Schlag-Rey et al. 1997; Everling, Dorris, and Munoz

1998; Gaymard et al. 1998; Conolly et al. 2000; Rafal

et al. 2000; Olk et al. 2006). Understanding the exact

role of these areas as part of the network, and which

rules and mechanisms underlie their processing, is

one of the major challenges of the interdisciplinary

field of studying visual attention and eye

movements.

Recent eye-movement studies have shown that where we

look is influenced by an array of factors (see Henderson

and Hollingworth 1999 and Henderson 2003 for

reviews). Low-level characteristics, such as contrast,

colour, texture and luminance of the visual stimuli,

affect which areas are fixated – that is, areas of higher

contrast are fixated more (Reinagel and Zador 1999;

Parkhurst and Niebur 2003). And as mentioned above,

the mere appearance of a stimulus draws our eyes

towards it. The ‘urge to look’ at something that appears

is so strong that at times we may not be able to prevent

it. This is illustrated by studies investigating how well we

can control where we look. Even in a seemingly easy task

in which participants are requested to refrain from

looking at a suddenly appearing stimulus on the

computer screen, such as a simple dot, and to look in

the opposite direction instead, erroneous saccades

towards the stimulus occur (Godijn and Kramer 2006;

Olk and Kingstone 2003; Reuter et al. 2006).

At a more intermediate level, shape and spatial relation

guide our eyes (Henderson and Hollingworth 1999) –

that is, a stimulus of a different shape than the

surrounding stimuli will be particularly visually salient

and attract attention and gaze (Duncan and Humphreys

1989; Harvey et al. 2002). And last but not least, eye

movements are also controlled by high-level factors,

such as information about previously fixated areas in a

current scene stored in short-term memory and spatial

FIGURE 1. Example of a scanpath, with circles representing fixations and arrows representing saccades.

164 A. Kappas & B. Olk

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and semantic knowledge about similar types of scenes

stored in long-term memory – for example, when

viewing a beach scene, we know that the beach is likely

to be found at the bottom of the picture whereas the sky

is likely at the top of the picture (Henderson 2003). Such

knowledge-guided exploration was, for example,

observed in a study by Shinoda, Hayhoe, and

Shrivastava (2001), who tracked eye movements while

participants looked at dynamic street scenes. The results

showed that the likelihood of fixating a traffic sign was

higher if this sign was shown at an intersection than

mid-block. Knowledge-driven eye-movement control

seems to increase over time with scene viewing as more

knowledge is accumulated about the identity of the

objects and their relationship to each other and to the

scene (Henderson, Weeks, and Hollingworth 1999).

Recent research also indicates that emotional content

affects where we look (Nummenmaa, Hyona, and Calvo

2006). Participants were presented with two pictures at a

time, one picture with either an unpleasant, neutral or

pleasant content, along with a neutral picture.

Importantly, arousal values and also low-level features,

such as colour saturation and contrast and luminance

levels, were kept constant. Participants freely looked at

the pictures and estimated whether the affective valence

of the two pictures was similar or not. The results

showed that participants tended to direct their first eye

movement to the emotional pictures and fixated those

for longer than the neutral pictures, irrespective of

valence.

There is consensus that pictures are viewed in an active

manner and observers search for relevant information,

in line with their goals. People, faces and informative

regions are fixated more (Mackworth and Morandi

1967; Henderson and Hollingworth 1999). That the

intentions of the observer play a very important role was

already shown in the seminal study by Yarbus (1967). In

his experiment, the participants looked at the picture

‘They did not Expect Him’ by the painter Repin. On this

picture a family is shown in a living room, and a person

enters the room. Yarbus recorded where his participants

were looking. In the different conditions of the

experiment the participants either engaged in free

viewing or they were asked, for example, to estimate the

social status of the persons, their age, to memorise the

clothing of the persons or to estimate for how long the

person entering the room had been away from his

family. The impressive finding was that the fixation

patterns differed depending on the task. When

participants were asked about the economic

standing of the persons on the picture, they looked

predominantly on the clothes of a person shown in the

foreground of the picture and on the furniture in the

room. When they were asked about the age of the

persons, they tended to look at the faces. When asked to

memorise the clothing, they mostly looked at the clothes

and when asked to estimate for how long the person

entering the room had been away, their gaze moved very

frequently back and forth between the faces of the

persons. Thus, the distribution of fixations and saccades

changed depending on the type of information required,

showing that participants actively sought pieces of

information that were relevant for the task they had to

complete. Based on these findings, Yarbus concluded

that observers look at elements that are considered by

them to convey information relevant for the perception

of the picture. Yarbus went so far as to suggest that eye

movements reflect the thought processes of the

observers, and therefore allow us to make, to a certain

degree, inferences about the thoughts of the observers.

More recent studies that recorded saccades while

participants engaged in everyday life tasks, such as

making tea and driving (Land and Lee 1994; Land,

Mennie, and Rusted 1999; Shinoda, Hayhoe, and

Shrivastava 2001) or that have addressed the effects of

expectations of actions and events on fixation patterns

(Jin and Olk 2007) confirm that observers look at areas

that are significant for the task at hand and that

observers look at a given object or a location just before

it becomes relevant for an action or an event to occur.

To study how people explore their visual world is of

great importance to research on visual competence. Not

only are the studies informative with respect to what

attracts our attention and our eyes, but one could claim

that making an appropriate selection of the visual

stimuli that are focused on is an indicator for a visually

competent person. Following this thought, one could

make the prediction that a more visually competent

person may select different stimuli than a less visually

competent person, and as a result behave differently

from them. Individual differences (see below) support

this view.

FACE PERCEPTION

Humans are a social species. Thus, the perception of

faces is one of the earliest and most important visual

tasks. In consequence, the study of face perception has a

long history and the related findings have shaped our

understanding of vision.

For the adult, a face is a source of information about the

identity of other human beings, their age and gender,

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but also their current intentions, attitudes and feelings

(Kappas 2003). Within a fraction of a second we make

judgements concerning the personality or the

trustworthiness of others (Willis and Todorov 2006).

Such decisions are based on the physiognomy – that is,

the morphological features of the face – but also on

subtle aspects of how facial movements unfold

dynamically (Krumhuber et al. 2007).

For the infant, faces are the primary means of learning

about themselves and their social and physical

environment. Early interaction with caregivers can be

interpreted as the ‘cradle of social cognition’ (Rochat

and Striano 1999, 30). Thus, a primary task for infants is

directing their visual attention to faces. Early research

suggested that newborns have a preference for face-like

configurations (e.g. Goren, Sarty, and Wu 1975).

Specifically, when confronted with different types of

moving stimuli, infants shortly after birth would be

more attracted to face-like objects than to objects that

contain the features of a face but in a scrambled fashion.

While certain aspects of this and similar studies were

questioned (e.g. Johnson et al. 1991; Turati 2004),

evidence now strongly suggests that of those patterns

that occur naturally in an infant’s environment, it is

faces that it will turn to. Moreover, similar preferences

for schematic faces were also found in nonhuman

primates (Kuwahata et al. 2004). Interestingly, infants

are not only attracted by faces, they react to them in

rather specific ways. In a celebrated study, Meltzoff and

Moore (1977) demonstrated that infants younger than

one month of age tended to imitate certain facial

movements. These findings provided some conceptual

challenges – how can a particular facial pattern be

matched without possessing the cognitive prerequisites

for symbolic representation? In other words, how can

you imitate a smile when you have not yet developed a

mental concept of a smile, a self or another person?

Recent work may point to the answer. A certain type of

neuron has been identified that is active in an individual

either when the person performs a particular movement,

or when the same movement is observed. These cells,

originally dubbed ‘monkey-see-monkey-do’ neurons,

are now referred to as mirror neurons (Rizzolatti and

Arbib 1998). It is believed that such neurons are

the basis of a mirror system that is important for

learning how to speak and more generally how to

connect with others emotionally (Kappas and

Descoteaux 2003).

The consequence of infants’ focusing on adults visually,

and imitating their actions, is to initiate a tightly

coupled interaction system with them, which allows

learning of appropriate and inappropriate reactions –

within a given culture. In other words, the biologically

rooted specialisation for faces can bootstrap learning

that then provides the capacity to develop locally

relevant norms and standards. Vision and action are

tightly linked from Day One.

Is the processing of faces still ‘special’ in adults? There is

some evidence to this effect. Neuropsychologists have

described a rare disorder, Prosopagnosia – Face Blindness,

that is associated with a highly specific deficit in

recognising faces. Even familiar members of the patient’s

family cannot be distinguished on the basis of their face.

At the same time, other visual expertise appears

relatively intact – even, at least in the case of people born

with prosopagnosia, distinguishing between different

facial expressions (Humphreys, Avidan, and Behrmann

2007).

Nancy Kanwisher, one of the most prominent

researchers on face perception, has identified an area of

the brain in the fusiform gyrus of the cortex that seems

to be dedicated to the processing of faces – the fusiform

face area (FFA; Kanwisher, McDermott, and Chun

1997). Kanwisher argues that some aspects of visual

processing are associated with dedicated machinery in

the brain – for example, dealing with faces. This might

be ‘hard-wired’ (in the sense of being innate) due to

evolutionary advantages, but it could also be explained

by the massive exposure we have to faces early in life and

later on as well (see Kanwisher 2006).

However, it is important to note there are apparently

other brain regions involved in processing faces, such as

the superior temporal sulcus and the occipital face area

(see Bouvier and Engel 2006). In fact, Haxby and his

colleagues (Haxby et al. 2001) have argued that face

processing is distributed across different brain regions

because even areas that react primarily to other objects,

such as houses, might contribute to a specific pattern of

brain activation associated with faces – even if the FFA is

particularly sensitive to faces.

Challenging Kanwisher, Isabel Gauthier has argued that

the FFA reacts particularly to faces because humans are

so much exposed to faces and have to distinguish

between them. The region identified as being specific to

the processing of faces is, she argued, instead just

relevant for making distinctions between members of a

class of objects of a particular visual complexity. To

support her claims she has presented data involving car

and bird experts processing images of cars, birds and

faces. In fact, there was a clear increase in brain activity

in the FFA when processing objects that fall into the

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acquired expertise (Gauthier et al. 2000). She also

created new synthetic objects, so-called Greebles that

differ from one another with regard to several structural

features (Gauthier and Tarr 1997, see Figure 2 above).

Participants in her experiments have to learn to

distinguish and identify the various different Greebles.

Once they have become experts, they show activation

near the FFA when processing Greebles. These findings

clearly demonstrate that learned visual expertise can

correlate with specific brain responses.

One of the problems in studying responses to faces with

the intent of making general inferences about visual

expertise is that all of the studied people are face experts

– thus, it is difficult to distinguish between how people

react to faces and how people react to stimuli for which

they are experts. Here Grelotti and colleagues (Grelotti

et al. 2005) presented interesting data of a boy with

autism who had a special interest in ‘Digimon’

characters, but who is not a face expert.1 Compared with

controls (an individual not suffering from autism, as

well as an individual suffering from autism but not

sharing the interest in the cartoon characters), the boy

shows activation in fusiform gyrus when discriminating

Digimon characters, but not faces! This suggests

that this area is related to visual expertise, particularly

as regards the identification of instances in a

category, and not just the visual properties of

a stimulus.

The debates concerning the exact role of the FFA cannot

be resolved today. It is clear, however, that the

possibility to investigate the living brain while it

performs certain aspects of visual processes – for

example, using functional Magnetic Resonance Imaging

(fMRI) – has considerably changed and increased our

understanding of how faces and other visuals are

processed. For some types of stimuli, such as faces or

bodies, we are all experts – this means that we are very

good at identifying them, discriminating between them,

remembering them. They also might attract attention

(see previous section). For other types of stimuli we can

become experts via repeated exposure and/or training.

Being an expert in some visual domain is likely resulting

also in differences in brain activation that can be

observed and measured. While on the one hand it is not

surprising that the activity of the brain is linked to what

it does, it is a reminder that physiological activation can

inform the development of models in specific domains,

such as visual expertise.

INTER-INDIVIDUAL DIFFERENCES

Discussing the complexity of seeing and perceiving, the

exploration of the visual world and face processing in the

context of visual competence necessitates considering

that not all humans perceive and explore the visual world

in the same manner. Yarbus (1967, 192) already

speculated that different educational and cultural

backgrounds could lead to quite different fixation

patterns. Inter- and also intra-individual differences when

viewing scenes have been reported and although similar

regions may be looked at, the sequence of fixations may

vary (Henderson 2003). Tatler, Baddeley, and Gilchrist

(2005) illustrate the importance of strategies employed by

observers. In their experiment, participants had to look at

natural scenes and memorise them. The results showed

that the consistency of eye-movement patterns between

observers decreased over time and that this decrease

could be best explained by strategic divergence.

Considering expertise, the way someone looks at a scene

is clearly affected by the knowledge and expertise that a

person has. In a study by Parkhurst, Law, and Niebur

(2002), the variability between participants’ fixation

locations was greater for images for which knowledge

was relevant (e.g. exploring pictures of home interiors

compared with artificial patterns). Experiments that

FIGURE 2. Examples of ‘Greebles’ used by Isabel Gauthier and her collea-gues to study the effects of visual expertise on activation in fusiform gyrusof the human cortex. Participants who have learned to discriminatebetween different Greebles show activation in or near the area thatis involved in processing faces. Image reproduced courtesy of IsabelGauthier and Michael J. Tarr.

Visual competence 167

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compare eye movements of experts and novices, for

example in sports (e.g. Kato, and Fukuda 2002; Nagano,

Kato, and Fukuda 2004; Naito, Kato, and Fukuda 2004)

or chess (Charness et al. 2001), showed that the visual

search strategies of experts and novices differed

significantly. Soccer experts fixated more often on the

knee and the hip regions of opponents than novices did,

suggesting that information gained from these areas was

important in anticipating an opponent’s next move

(Nagano, Kato, and Fukuda 2004). In another study, eye

movements of expert and intermediate chess players were

monitored while they were required to choose the best

move in five chess positions. Naturally, the experts were

faster and more accurate than intermediates in choosing

the best move. When the spatial distribution of the first

five fixations for each position were examined, the eye-

movement patterns of the experts showed that they made

more fixations on empty squares than did intermediates

and when they looked at pieces, they looked more

frequently on relevant pieces than did intermediates.

According to the authors, these results may indicate that

expert chess players encode chess configurations instead

of individual pieces and that their exploration is guided

by peripheral vision, allowing them to select the target of

their next fixation by piece saliency (Charness et al. 2001).

Similarly, Vogt and Magnussen (2007) demonstrated

expertise effects in artists compared with non-trained

observers in an eye-tracking study.

For the concept of visual competence, such work may

suggest that it depends on the knowledge and expertise

that a person has and, importantly, that it is not static

but may increase – for example, with acquiring expertise.

As hardly any person will be an expert for everything, it

may well be that visual competence may also vary within

a person. How far competence transfers from one

domain of expertise to another requires further

empirical investigation.

Visual competence can also decrease. This could be due to

peripheral factors – for example, by injuries to the eyes

that cannot be remedied or by impairments shown by

patients with brain injuries (e.g. after a stroke). Injuries to

the visual pathway can lead to deficits, such as

hemianopia, which is the loss of vision in half of the visual

field. Such patients tend to compensate for their deficit,

though, by performing more saccades to the hemianopic

side (Ishiai, Furukawa, and Tsukagoshi 1987) and

spending more time exploring on that side (Behrmann

et al. 1997).

Other patients may suffer from visual agnosia, the loss of

the ability to identify objects despite being able to see

them, or of visuospatial neglect, shown in deficits in

exploring the visual world, for example due to

difficulties in allocating visual attention (Olk and

Harvey 2006). Spatial neglect has been defined as the

failure ‘to respond or orient to novel or meaningful

stimuli presented to the side opposite a brain lesion’

(Heilman, Valenstein, and Watson 1985). Although

visual field deficits such as hemianopia often

accompany neglect, neglect can also be seen in cases

without such impairments (Halligan, Marshall, and

Wade 1990) and is believed to arise at higher levels of

processing (Bisiach and Luzatti 1978; Riddoch and

Humphreys 1987; Milner and Goodale 2006; Harvey

1998). It can be demonstrated after injuries to the right

or to the left side of the brain, but seems to be much

more frequent and severe after right-sided lesions

(Weintraub and Mesulam 1987; Vallar 1993), leading to

impaired exploration and perception of the left side of

space. Neuropsychological assessment typically

comprises cancellation tasks, in which the patient is

required to find and cross out objects (e.g. lines, stars or

letters that are distributed on a sheet of paper and are

sometimes embedded amongst distracters). A sign of

neglect would be if a patient failed to cross out the

objects on one side. In everyday life, these patients

might fail to eat food from one side of the plate and run

into objects (e.g. doorframes) that are located on the

impaired side. Other tests assess the perception and

representation of objects by requiring the drawing of a

picture from memory or the ability to copy figures. A

battery which incorporates most of these tests is the

‘Behavioural Inattention Test’ (Wilson, Cockburn, and

Halligan 1987). Examples of two subtests are illustrated

in Figure 3.

Investigations of eye-movement behaviour in spatial

neglect have shown that although patients are able to

execute leftward saccades (Karnath, Niemeier, and

Dichgans 1998), they demonstrate a rightward deviation

of exploratory gaze (Karnath and Fetter 1995; Karnath,

Niemeier, and Dichgans 1998; Harvey et al. 2002), begin

their exploration in right hemispace and, compared with

healthy persons, spend relatively less time exploring the

left but relatively more time exploring right space

(Behrmann et al. 1997). Saccades to the right,

unimpaired side may be initiated particularly quickly

(Olk, Harvey, and Gilchrist 2002).

Taken together, the examples of expertise and of the

effects of brain injuries on visual exploration behaviour

show that a concept of visual competence should

acknowledge that it is not static and can vary between

and within persons.

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The latter point is also illustrated by intercultural

differences. Most of the research on visual processes

originates in a few countries. Typically the authors

appear to assume that the processes under study are

universally applicable. However, there is reason to

believe that there can be specific cultural differences in

how people conceive of themselves and how they relate

to their social and non-social world. This has an impact

on basic perceptual processes, as has been repeatedly

demonstrated recently. For example, Chua, Boland, and

Nisbett (2005) showed the impact of culture and

processing styles on fixation patterns. They measured

FIGURE 3. Performance of a patient with spatial neglect in two subtests of the Behavioural Inattention Test: a) line crossing; b) figure copying.

Visual competence 169

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eye movements of American and Chinese participants

while they explored photographs of natural scenes. The

results showed that the Americans fixated foreground

objects sooner and longer than the Chinese participants,

while the Chinese participants made more saccades to

the background than did the Americans, a result in line

with possible differences in expertise, socialisation and

experience of the two groups. Such differences may

influence the allocation of attention, reflected in the eye-

movement patterns. Understanding these differences is

not only of theoretical interest, but, in the context of

visual communication, of concrete relevance for

applications. For example, layouts of press media, or the

structure of images used on television or the Internet,

cannot be assumed to be globally appropriate. In

addition, there are content issues that relate to symbols

and associations that may differ considerably from

culture to culture and might lead to strife and conflict

(e.g. Muller and Ozcan 2007).

APPLICATIONS

Much of the research described in this contribution is

targeted at the illumination of basic processes and not

applications in the real world. Nevertheless, we would

like to claim that this basic research has large potential

for applied use. The findings regarding the activation in

specific brain regions linked to visual expertise (see

section on face processing) could indicate that brain

research might have a diagnostic value for expertise.

Similarly, studies using eye-tracking methodology have

shown differences between novices and experts and

highlight difficulties of persons with brain injuries. A

very interesting application of such methods might be to

assess how training changes the way that certain types of

visuals are perceived and processed, or, in other words,

how visual competence can be enhanced.

Basic research has also shown which properties of visuals

– such as contrast, complexity, distribution of objects,

symbols used – affect where we attend and look, not to

forget profound inter- and intra-individual differences

within and between cultures. The consideration of such

findings has the potential to greatly enhance the choices

of media-producers that are typically driven by personal

experience and intuition. In turn, the methods

developed in the context of psychological research and

neuroscience can be useful tools in the evaluation of

effectiveness or, in the negative, in the potential for

communication failure.

Certain stimuli, such as faces, may be processed in a

specific way – they appear to attract attention and

require few cognitive resources. For example, the

communication of emotions is rapid. Faces are often

interpreted as expressing an emotion, and if certain

stereotypical patterns of facial activation are shown, this

process can take place in a few milliseconds (e.g. Kirouac

and Dore 1984). However, this does not mean that the

perceived emotion is necessarily corresponding to the

emotional state of the person depicted. Thus, a smile

might be recognised as a smile but this does not mean

the smiling person is indeed happy (Kappas 2003)!

In the case of emotional displays, perception involves

the activation not only of knowledge (‘this person is

happy!’), but also of structures that are associated with

the experience of emotions in the individual. There is

much evidence for such an embodied communication

of affect (Kappas and Descoteaux 2003). This could

mean that showing suffering victims of violence in a

news programme might have a very physical impact

on the observers due to very basic processes that

link perception and experience of emotions. Basic

research from this area is relevant for the decision

process of an editor regarding what should be shown

and how.

The processing of human movement is also associated

with specific brain regions, such as the superior

temporal sulcus (e.g. Michels, Lappe, and Vaina 2005),

as well as the aforementioned mirror system. Calvo-

Merino and his colleagues (2005, 2006) could

demonstrate that expertise in classical dance or Capoeira

influences the activation of the mirror system when

watching the types of movements for which the

individual was, or was not, an expert. Again, this offers

the potential for diagnostic uses. However, it also

underlines the fact that different observers will perceive

certain types of media very differently. Taking such

findings into account might allow tailoring contents and

form to maximise the success and impact of specific

mediate messages.

CONCLUSIONS

The availability of new methods of studying ongoing

activity of the brain in recent years, systematic study of

patients with neuropsychological methods and

behavioural methodologies with a variety of participant

groups, has greatly increased our understanding of how

visual information is processed. Sometimes

neuroscientific findings are criticised because ‘just

finding a location where the brain is activated during a

particular process does not help understanding the

associated mental processes’. This is true. However, the

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body of research addressing the issue of vision is diverse

and mostly driven by theories. And it is important to

consider that no method alone can unravel all the

mysteries of vision, but that converging findings using

different methodologies within psychology and

neuroscience should be considered.

In fact, by now, the body of knowledge and the research

methods are so solid that it is time for an exchange with

experts in visual research from different disciplines. This

exchange requires patience, because the level of control

that laboratory research requires cannot be easily

translated into a naturalistic situation. Similarly,

studying the perception of dots, lines and arrows is not

the same as watching a newscast of a terrorist attack as it

unfolds in real time. But in our view, the reward of such

collaborations with other disciplines should be

significant new insights, making the effort worthwhile.

The concept of visual competence that is the focus of this

special issue has the potential to serve as a nexus of basic

and applied interests. Thus, we have provided a cursory

description of the state of knowledge with regard to some

selected aspects of vision as seen by the psychological and

brain sciences. While a detailed review is well beyond the

scope of this manuscript, we hope that we succeeded in

creating interest in the type of basic research that is

currently being conducted in psychology and

neuroscience laboratories in those readers who might not

be familiar with it or who thought that it is unrelated to

their interests. If such interest is created, then one

important prerequisite for exchange is taken care of.

We believe that the field of psychology has much to gain

from an inter-disciplinary exchange in the context of

‘visual competence’. First, psychology can expect to be

inspired with respect to specific research questions to

ask and to test whether psychological models and

theories hold true in the complex real world outside the

laboratory. Second, tackling research questions from

different angles and learning about methods used in

other disciplines should be exceptionally fruitful. We are

currently in the process of dealing with such an

interdisciplinary endeavour and we are convinced that it

is possible to bridge the complex divides between the

disciplines that are linked to differences regarding not

only the type of visual material studied, but also the

paradigms and models, and even the usage of the most

basic terms, such as ‘information’ or ‘knowledge’. We

are sensitised to these issues. And it is precisely for these

reasons that we want to communicate what we consider

essential: a discussion of the concept of visual

competence would not be complete without a

consideration of basic mental/neural processes within

the individual.

NOTE

[1] It has been argued that autistic individuals do not develop

a theory of mind, due to them not understanding or

recognising mental states in others (Klein and Kihlstrom

1998). It is believed that there are deficits in perceiving

and interpreting nonverbal social behaviours displayed by

others, though performance regarding the identification of

faces is unclear, but there is evidence pointing towards

deficits as well (McGee and Morrier 2003).

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