In a lively exchange over what has come to be referred to as "the Chinese room argument", John Searle sought to refute the claim of proponents of what he calls "strong artificial intelligence AI " that a computer program can be conscious, though he does agree with advocates of "weak AI" that computer programs can be formatted to "simulate" conscious states.
His own view is that consciousness has subjective, first-person causal powers by being essentially intentional due simply to the way human brains function biologically; conscious persons can perform computations, but consciousness is not inherently computational the way computer programs are. To make a Turing machine that speaks Chinese, Searle imagines a room with one monolingual English speaker Searle himself, in fact , a book that designates a combination of Chinese symbols to be output paired with Chinese symbol input, and boxes filled with Chinese symbols.
In this case, the English speaker is acting as a computer and the rulebook as a program. Searle argues that with such a machine, he would be able to process the inputs to outputs perfectly without having any understanding of Chinese, nor having any idea what the questions and answers could possibly mean.
If the experiment were done in English, since Searle knows English, he would be able to take questions and give answers without any algorithms for English questions, and he would be effectively aware of what was being said and the purposes it might serve. Searle would pass the Turing test of answering the questions in both languages, but he is only conscious of what he is doing when he speaks English. Another way of putting the argument is to say that computer programs can pass the Turing test for processing the syntax of a language, but that the syntax cannot lead to semantic meaning in the way strong AI advocates hoped.
In the literature concerning artificial intelligence, Searle's essay has been second only to Turing's in the volume of debate it has generated. But other thinkers sympathetic to his basic argument have suggested that the necessary though perhaps still not sufficient extra conditions may include the ability to pass not just the verbal version of the Turing test, but the robotic version,  which requires grounding the robot's words in the robot's sensorimotor capacity to categorize and interact with the things in the world that its words are about, Turing-indistinguishably from a real person.
Turing-scale robotics is an empirical branch of research on embodied cognition and situated cognition. In , Victor Argonov has suggested a non-Turing test for machine consciousness based on machine's ability to produce philosophical judgments. However, this test can be used only to detect, but not refute the existence of consciousness.
"We have no real answer to the question 'what is consciousness?'"
A positive result proves that machine is conscious but a negative result proves nothing. For example, absence of philosophical judgments may be caused by lack of the machine's intellect, not by absence of consciousness. For many decades, consciousness as a research topic was avoided by the majority of mainstream scientists, because of a general feeling that a phenomenon defined in subjective terms could not properly be studied using objective experimental methods. Modern medical and psychological investigations into consciousness are based on psychological experiments including, for example, the investigation of priming effects using subliminal stimuli , and on case studies of alterations in consciousness produced by trauma, illness, or drugs.
Broadly viewed, scientific approaches are based on two core concepts. The first identifies the content of consciousness with the experiences that are reported by human subjects; the second makes use of the concept of consciousness that has been developed by neurologists and other medical professionals who deal with patients whose behavior is impaired. In either case, the ultimate goals are to develop techniques for assessing consciousness objectively in humans as well as other animals, and to understand the neural and psychological mechanisms that underlie it. Experimental research on consciousness presents special difficulties, due to the lack of a universally accepted operational definition.
In the majority of experiments that are specifically about consciousness, the subjects are human, and the criterion used is verbal report: in other words, subjects are asked to describe their experiences, and their descriptions are treated as observations of the contents of consciousness. In several paradigms, such as the technique of response priming , the behavior of subjects is clearly influenced by stimuli for which they report no awareness, and suitable experimental manipulations can lead to increasing priming effects despite decreasing prime identification double dissociation.
Verbal report is widely considered to be the most reliable indicator of consciousness, but it raises a number of issues.
As a third issue, philosophers who dispute the validity of the Turing test may feel that it is possible, at least in principle, for verbal report to be dissociated from consciousness entirely: a philosophical zombie may give detailed verbal reports of awareness in the absence of any genuine awareness.
Although verbal report is in practice the "gold standard" for ascribing consciousness, it is not the only possible criterion. The last three of these can be used as indicators of consciousness when verbal behavior is absent.
Their reliability as indicators of consciousness is disputed, however, due to numerous studies showing that alert human subjects can be induced to behave purposefully in a variety of ways in spite of reporting a complete lack of awareness. Another approach applies specifically to the study of self-awareness , that is, the ability to distinguish oneself from others.
In the s Gordon Gallup developed an operational test for self-awareness, known as the mirror test.
The test examines whether animals are able to differentiate between seeing themselves in a mirror versus seeing other animals. The classic example involves placing a spot of coloring on the skin or fur near the individual's forehead and seeing if they attempt to remove it or at least touch the spot, thus indicating that they recognize that the individual they are seeing in the mirror is themselves. A major part of the scientific literature on consciousness consists of studies that examine the relationship between the experiences reported by subjects and the activity that simultaneously takes place in their brains—that is, studies of the neural correlates of consciousness.
The hope is to find that activity in a particular part of the brain, or a particular pattern of global brain activity, which will be strongly predictive of conscious awareness. Several brain imaging techniques, such as EEG and fMRI , have been used for physical measures of brain activity in these studies. Another idea that has drawn attention for several decades is that consciousness is associated with high-frequency gamma band oscillations in brain activity. This idea arose from proposals in the s, by Christof von der Malsburg and Wolf Singer, that gamma oscillations could solve the so-called binding problem , by linking information represented in different parts of the brain into a unified experience.
A number of studies have shown that activity in primary sensory areas of the brain is not sufficient to produce consciousness: it is possible for subjects to report a lack of awareness even when areas such as the primary visual cortex show clear electrical responses to a stimulus.
There is substantial evidence that a "top-down" flow of neural activity i. Modulation of neural responses may correlate with phenomenal experiences. In contrast to the raw electrical responses that do not correlate with consciousness, the modulation of these responses by other stimuli correlates surprisingly well with an important aspect of consciousness: namely with the phenomenal experience of stimulus intensity brightness, contrast.
In , Graziano and Kastner  proposed the "attention schema" theory of awareness. In that theory, specific cortical areas, notably in the superior temporal sulcus and the temporo-parietal junction, are used to build the construct of awareness and attribute it to other people. The same cortical machinery is also used to attribute awareness to oneself.
New Research In
Damage to these cortical regions can lead to deficits in consciousness such as hemispatial neglect. In the attention schema theory, the value of explaining the feature of awareness and attributing it to a person is to gain a useful predictive model of that person's attentional processing.
Attention is a style of information processing in which a brain focuses its resources on a limited set of interrelated signals.
Awareness, in this theory, is a useful, simplified schema that represents attentional states. To be aware of X is explained by constructing a model of one's attentional focus on X. In , the perturbational complexity index PCI was proposed, a measure of the algorithmic complexity of the electrophysiological response of the cortex to transcranial magnetic stimulation.
This measure was shown to be higher in individuals that are awake, in REM sleep or in a locked-in state than in those who are in deep sleep or in a vegetative state,  making it potentially useful as a quantitative assessment of consciousness states. Assuming that not only humans but even some non-mammalian species are conscious, a number of evolutionary approaches to the problem of neural correlates of consciousness open up.
For example, assuming that birds are conscious—a common assumption among neuroscientists and ethologists due to the extensive cognitive repertoire of birds—there are comparative neuroanatomical ways to validate some of the principal, currently competing, mammalian consciousness—brain theories. The rationale for such a comparative study is that the avian brain deviates structurally from the mammalian brain.
So how similar are they? What homologues can be identified? The general conclusion from the study by Butler, et al. The structures assumed to be critical for consciousness in mammalian brains have homologous counterparts in avian brains. Thus the main portions of the theories of Crick and Koch,  Edelman and Tononi,  and Cotterill  seem to be compatible with the assumption that birds are conscious.
Edelman also differentiates between what he calls primary consciousness which is a trait shared by humans and non-human animals and higher-order consciousness as it appears in humans alone along with human language capacity. For instance, the suggestion by Crick and Koch that layer 5 neurons of the mammalian brain have a special role, seems difficult to apply to the avian brain, since the avian homologues have a different morphology.
Consciousness of the World and the World of Consciousness
The assumption of an avian consciousness also brings the reptilian brain into focus. The reason is the structural continuity between avian and reptilian brains, meaning that the phylogenetic origin of consciousness may be earlier than suggested by many leading neuroscientists. Joaquin Fuster of UCLA has advocated the position of the importance of the prefrontal cortex in humans, along with the areas of Wernicke and Broca, as being of particular importance to the development of human language capacities neuro-anatomically necessary for the emergence of higher-order consciousness in humans.
Opinions are divided as to where in biological evolution consciousness emerged and about whether or not consciousness has any survival value. Some argue that consciousness is a byproduct of evolution.
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- teetallinkmindcert.gq | Science, health and medical journals, full text articles and books..
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- Introduction to Consciousness | Boundless Psychology.
- Berchtesgrund (German Edition)?
- Introduction to Consciousness | Boundless Psychology.
It has been argued that consciousness emerged i exclusively with the first humans, ii exclusively with the first mammals, iii independently in mammals and birds, or iv with the first reptiles. Regarding the primary function of conscious processing, a recurring idea in recent theories is that phenomenal states somehow integrate neural activities and information-processing that would otherwise be independent. Another example has been proposed by Gerald Edelman called dynamic core hypothesis which puts emphasis on reentrant connections that reciprocally link areas of the brain in a massively parallel manner.
These theories of integrative function present solutions to two classic problems associated with consciousness: differentiation and unity. They show how our conscious experience can discriminate between a virtually unlimited number of different possible scenes and details differentiation because it integrates those details from our sensory systems, while the integrative nature of consciousness in this view easily explains how our experience can seem unified as one whole despite all of these individual parts. However, it remains unspecified which kinds of information are integrated in a conscious manner and which kinds can be integrated without consciousness.
Nor is it explained what specific causal role conscious integration plays, nor why the same functionality cannot be achieved without consciousness. Obviously not all kinds of information are capable of being disseminated consciously e. For a review of the differences between conscious and unconscious integrations, see the article of E.