Summary with Consciousness Blackmore & Troscianko - 3rd edition
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Many philosophers are still in disagreement of whether the concept of attention is a real thing or not. The very familiarity of the concept of attention can make it hard to think about clearly, but perhaps we should start with how it feels. The metaphor of the ‘spotlight of attention’ comes easily to mind because paying attention feels this way – like directing a light on some things and not others. Perhaps it feels as though attention makes things or thoughts brighter, more prominent, or more focused.
Attention feels like something extra. Hamilton, for instance, described it as, ‘Attention is like concentrated consciousness.’ It feels like the intensity of things increase when you focus attention on them.
And while we shouldn’t thing of attention’s metaphors – such as the spotlight – as something real, experiments have found that the metaphor of ‘lighting up’ has an almost realistic equivalent: a real attentional ‘spotlighting’ effect in visual perception. Participants kept their eyes fixated on the fovea, where spatial resolution is highest, and were shown textures in the periphery, where it is much lower. When they attended to the textures, they could more easily distinguish them. It was as though their spatial resolution had improved. Crucially, in tasks where enhanced resolution actually makes the task harder, the same effect was found for focused attention too: participants’ performance got worse. Later experiments found that the same effect for brightness, contrast, and colour saturation, but not for differences in hue. It seems that, as in James’s notion of focalisation and concentration, attention actually increases the spatial resolution of what we see. It may also change visual and other sensory experience in different ways depending on context, so it seems that attention can qualitatively shape the kinds of conscious experiences we have – even if, as James also pointed out, we know how to adjust for these effects so we are not misled into thinking the light actually just got brighter.
The image of the spotlight of attention is well known, but perhaps, looking at your own experience, there might be a couple of different metaphors applicable too. This is one way for what we call ‘first-person practice’ to relate to consciousness and one reason why we ask you to devote time and energy to the ‘exercises’ suggested in each chapter: we cannot hope to understand consciousness in general unless we are familiar with our own personal version of it. And the idea of ‘paying careful attention to experience’ implies that attention itself is at the heart of all such practice. We will begin with a basic element of our everyday experience of attention, the directing of attention, and ask what basic facts we can establish about it.
Imagine you are sitting somewhere, and you turn to face a noise. What has happened? If someone asked you, you might say, ‘I heard the sound so I turned to look.’ Then, the causal sequence seems to be: 1) consciously hear sound; 2) turn round to look. It feels as though our conscious perception of the noise, possibly followed by a conscious decision to pay attention, is what caused us to turn around and pay attention. Is this right? Does conscious perception or conscious will cause attention to be directed to a specific place? If it does not always do so, can it ever do so?
We know that conscious effort and perception are not always required. Attention can be involuntarily grabbed or intentionally directed, and these processes each have different brain systems to them. Attention is drawn involuntarily when we react quickly to something like a loud noise, or our name being called, or an email notification on our phone, and only realise afterwards that we have done so. Such involuntary attention depends on the ventral attention system, which includes alerting and vigilance systems and is found mainly in the right hemisphere in frontal, parietal, and temporal areas. By contrast, when we deliberately pay attention to someone speaking, or try to ignore an annoying noise to concentrate on reading our book, this uses the dorsal attention system.
An example of involuntary attention is the ‘bottom-up’ control of eye movements (if you don’t remember the difference between bottom-up and top-down, look it up). Our eyes constantly jump around from one fixation point to another. These movements are called saccades and happen several times a second, whether we are aware of them or not. We can also control saccadic eye movements voluntarily. If a bright, salient, or moving object is detected in the periphery, the eyes quickly turn to bring that part of the visual world onto the fovea. This must be done very fast to be useful to a moving, acting animal and, not surprisingly, much of the control is coordinated by parts of the dorsal visual stream, in particular the posterior parietal cortex. In what is called ‘smooth pursuit’, the eyes can track a moving object, keeping its image on roughly the same part of the fovea. This kind of eye movement is hard to make without an actual moving target and is affected by drug use and by conditions such as schizophrenia, autism, and post-traumatic stress. It can continue without conscious awareness, as was shown in experiments with a man who was cortically blind. He could not consciously see movement at all, and when surrounded with a large moving stripe display he denied having any visual experience of motion. Yet his eyes behaved relatively normally in tracking the moving stripes, making slow pursuit movements followed by rapid flicks to catch up. This showed that although movement may be necessary for accurate pursuit, awareness of this movement is not.
Directing the eyes towards a particular object is not equivalent to paying attention to it though. First of all, it is perfectly possible to be blind to something we are looking right at, just because we are not attending to it, such as the inattentional blindness of chapter 3. Other kinds of blindness are an integral part of paying attention too. Attention always has costs as well as benefits. Not only does directing attention to one thing mean you have to neglect another, but there may be a short ‘attentional blink’ afterwards. For example, in an experiment, a series of letters are rapidly flashed and participants asked to look for a given target letter. If they successfully detect one, then they are less likely to detect another shown within 200–500 msec after the first, as though their capacity to attend ‘blinked’ for a moment, even though they were looking right at the relevant stimulus.
Generally speaking, as Helmholtz long ago demonstrated, it is perfectly possible to look directly at one object or place, and pay attention somewhere else, a skill now called ‘covert attention scanning’, as opposed to overt scanning, in which you pay attention where you’re looking. You can try this now by keeping your eyes on the page and attending to a location off to one side.
So as mentioned before, attention can be involuntarily grabbed as well as deliberately directed, and that attention and gaze sometimes operate together and sometimes not. But this does not necessarily tell us anything about consciousness. We might feel we have consciously chosen where to place our attention without consciousness actually playing a causal role – for example, the feeling of acting consciously might be a by-product or a later effect of the brain processes that selectively direct attention.
In the nineteenth century, Helmholtz, Hering, and Wundt were among the physiologists and psychologists who experimented with attention. In the 1950s, many experiments were performed with a method called dichotic listening, in which two different streams of sound are played to each ear. Remarkable on this is that, with people attentively listening, most didn’t even notice the messages have swapped ear. This raised the question of whether selection operated early on or after much processing had already taken place, leading to the early versus late selection debate which has never really been resolved – although more recently, as we will see in a moment, it has been sidestepped by the concept of perceptual load.
For a long time most theories treated attention as some sort of bottleneck, with preconscious sensory filters needed to decide what should be let through to the deeper stages of processing .This makes sense because clearly the brain has a limited capacity for detailed processing, and is a massively parallel system which produces serial outputs, such as speech and sequential actions. So somehow many parallel processes have to be brought together, or selected, to ensure that a sensible serial output occurs. The main problem with such theories was that to cope with the evidence, the proposed filters became more and more complicated, until the pre-attentive processing began to look as complex as the deeper processing to which it was supposed to give access.
The spotlight of attention was then seen as less like a narrow beam or single bottleneck and more like the outcome of many mechanisms by which the nervous system organises its resources, giving more to some items than others. At some point in its history, the science of attention arguably began to study – or create – something that bears little relation to the intuitive idea of attention as a sharpening of focus. Scientists have redefined attention as a perceptual filter, a feature-binding mechanism, a broadcaster to working memory, or a competitive bias process, so many that it is hard to keep up, really.
Perceptual load theory was proposed by psychologist Nilli Lavie as an attempt to return to the intuitive idea of a bottleneck of attention, and to rethink it in a simpler way. In this theory, perceptual processing has limited capacity, and when a task involves dealing with a large amount of information (high perceptual load), that capacity is fully exhausted by the processing of the attended-to information.
It retains the idea of awareness or consciousness as a location or container which things can get into only if they meet certain attentional criteria. It also relies on the idea of a ‘perceptual processing stream from unconscious to conscious levels.
What it comes down to is that there are many theories, spanning all the prior chapters yet.
Neuroscientist Giacomo Rizzolatti and his colleagues in Parma, Italy have suggested a ‘premotor theory’ of selective spatial attention in which attending to a particular position in space is like preparing to look or reach towards it.
However, there were some experiments with findings like these suggest that not all areas involved in motor preparation are involved in covert attention, and not all regions involved in covert attention have motor functions. Regions may be involved in both, but in the weaker sense of creating a ‘priority map which signals the location of behaviourally relevant stimuli’. Hence perhaps why dissociations between eye-movement preparation and attention allocation have been found for both overt and covert attention. So the proposal that attention and motor control use the same neural circuits, as well as the stronger claim that motor activation is both necessary and sufficient for spatial attention, may be going too far.
There are six main possibilities for how consciousness and attention relate to one another. Here are all six listed;
The basic problem is that whether and how something forms part of someone’s conscious experience can be determined only by either report (what people say) or other explicit decisions (what people do). But reporting on what we see requires us to attend to it. So too do many of the decision-making tasks that are used as criteria for consciousness. So, as philosopher James Stazicker puts it, ‘the failure to report an object of visual consciousness might reflect a failure to attend to the object, rather than an absence of visual consciousness of the object’ (2011, p. 163). In this case, how can we ever even begin to work out how consciousness and attention relate to or differ from each other? In Stazicker’s terms, how could we ever test whether their relationship is one of dependence or independence: whether the spotlight of attention falling on things is what makes them conscious, or whether it illuminates episodes of consciousness without constituting them?
But maybe we are making unnecessarily complicated assumptions about people’s illusions about their own experience. Maybe we can take people’s reports about their consciousness at face value, Stazicker suggests. What the cueing did was not make accessible some portion of an already conscious experience; instead, it made more determinate some information in that experience. This is not the same as claiming that, as in multiple drafts, attention exerts retroactive effects on our conscious experience, or what we think of as that experience. In this intermediate view, attention exerts effects on consciousness as it happens.
It is easy to assume that consciousness is an all-or-nothing kind of deal: we are conscious of something or we are not, there is no in between. But this may be one of the errors that prevents us from accurately assessing its relationship to attention. So where does this leave us? Searching for the neural correlates of consciousness might still sound like a nice idea: if we could find out what neural activity correlates with (say) visual consciousness, we could determine whether this activity ever occurs without those processes which correlate with attention. But this takes us back to problems we encountered in that chapter; how do we establish these correlates without first knowing whether or not one occurs without the other? Some people, like the philosopher Hilary Putnam, conclude that there is simply no way of answering the question of whether there is unreportable consciousness, however, this seems like an easy way out.
Meditation seems to be the ultimate training of attention. There many different forms of meditation, but the first step in nearly all of them is calming the mind. This skill can take many years to master, but then it becomes easy to sit down and let the mind settle. Everything that arises is let go, like writing on water. Nothing is met with judgement or opinions, and as reactions gradually cease, clarity appears. The sounds of birds, the sight of the floor, the itch on the hand, they are just as they are: suchness. Sounds easy, right?
Many traditions claim that in this decluttered state, insight into the mind can spontaneously arise. Those who practise certain kinds of meditation claim that they awake from illusion and see directly the nature of mind. If they are right, their claims are important both for the introspective methods they use, and for what they say about consciousness. But are they right?
Most methods of meditation have religious origins. In particular, Buddhism, Hinduism, and Sufism have long traditions of disciplined meditation, but comparable methods of silent contemplation are found within the mystical traditions of Christianity, Judaism, and Islam. Within these traditions, people meditate for widely different reasons and in many different ways. The more religious may want to gain merit, get to heaven, or ensure a favourable reincarnation, while others sit for insight, awakening, or enlightenment. Some fast, some kneel and some pray.
Despite their different origins, the basics of all types of meditation might be summed up in the words ‘pay attention and don’t think’. It is hard to believe that such a simple practice could create the kinds of transformations and insights claimed by some meditators, yet this is essentially the task undertaken. It is surprisingly difficult, as you will know if you have tried, and the many varieties of meditation can be seen as different ways of easing the task. If you have never tried it, do exercise 2.
Common to all forms of meditation are two basic tasks: paying attention and not thinking. Both raise interesting practical and theoretical questions. What do you pay attention to then? How do you maintain concentration? How do you not think? Is it even possible to not [ay attention to anything at all, not even your thoughts? The different methods outlined below give different answers, but almost all techniques share common methods for dealing with unwanted thoughts.
There are two types of meditation, open and concentrative. Open or receptive meditation means paying attention equally to everything that is happening, whether that is perceptions, feelings, or thoughts, but without responding. This is usually done with the eyes open or half-open. Concentrative meditation means paying focused attention to one thing without distraction, rather than remaining open to the wider world, such as focussing on the breath.
But how are these two related? The book really does not provide a concrete answer. Yay.
7.1 As many times as you can, every day, ask yourself ‘Did I direct my attention or was my attention grabbed?’ Was it you who consciously made the decision or did something else do it?
7.2 Sit down comfortably and close your eyes. Try not to think about anything. If that is hard, just focus on breathing. Do this for a minute.
Summary of all chapters of Consciousness by Blackmore & Troscianko
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