Self-awareness 1 страница

It seems natural that subjects possessing a capacity for discrimination of others’ mental states should be aware of corresponding native data, that is, possess self-awareness.

Self-awareness refers to consciousness of the self as a separate individual and occupies the next level above conscious awareness of events and objects in the world (Cartwright, 2002). It is a debated question whether non human animals are conscious and how such functioning has evolved (Griffin, 1984, 2001; Bekoff and Allen, 2002, Broom, 2003).

The objective study of self-recognition, with a mirror and a mark applied to the face, was conducted independently by a comparative psychologist Gallup (1970) for use with chimpanzees and monkeys, and by a clinical child psychologist Amsterdam (1972) for use with infant humans (for reviews see Anderson and Gallup, 1999; Bard et al., 2006).

Gallup (1970) developed a mirror test as an experimental paradigm for examining manifestations of self-awareness in animals basing on ideas that the use of the mirror for self-directed behaviour depends on self-awareness. Chimpanzees, after being given the chance to play with a mirror for 10 days, had a mark placed on their foreheads while they were anesthetized. Later they seemed to have no awareness of the mark until given access to a mirror, after which they began to touch their foreheads, using the mirror to guide their hands as they touched the mark on their own faces (rather than the mark on the mirror image). Gallup interpreted this behaviour as indicating self-recognition by the animals. Since that, only a few species passed this test and among them are chimpanzees (but not macaques and tamarins, see: Gallup, 1977; Hauser et al., 2001), orangutans (Swartz et al., 1999), cetaceans (Delfour and Marten, 2001; Reiss and Marino, 2001), and grey parrots (Pepperberg et al., 1995). Human children tend to fail this test until they are 3-4 years old. Members of several other species tested, for instance, dogs and 2 year old children usually react to a mirror in fear or with curiosity, or simply ignore it, while birds often attack their own reflections (for a detailed review see: Keenan et al., 2003).

In some experiments chimpanzees (Gallup et al., 1995), grey parrots (Pepperberg et al., 1995), and children of three years old (Amsterdam, 1972; Zazzo, 1979) were shown as being able to find hidden objects using a mirror to guide their behaviour. There are some evidences that animals that have not passed the mirror test for self recognition, are nevertheless able to use information provided by mirrors. Monkeys can use a mirror to locate a plastic flower that was suspended above their heads by means of a specially adapted collar (Anderson, 1984, Itakura, 1987). Povinelli (1989) describes occasions when an elephant carefully guided its trunk with the help of a mirror in order to retrieve a carrot that was not otherwise visible.

Marten and Psarakos (1995) developed an experimental paradigm combining the use of a mirror use and television tracks in order to adopt this experimental technique for studying self-awareness in dolphins. When a dolphin looks in a mirror it often opens its mouth and moves its head around in some rhythmic fashion. In a mark test, as it does not have a hand to touch its mark, the dolphin manoeuvres its body in various postures to see it. These behaviours are likely to be contingency-checking and self-examination, respectively. However, another possible interpretation is that the dolphin is using postures to interact " socially" with what he perceives to be another dolphin in the mirror. To distinguish self-examination from social behaviour, researchers put a video camera aimed into the tank next to the television monitor. A real-time image is displayed on the dolphin's television, allowing the dolphin to look at itself as in a mirror; this material is videotaped. The dolphins were exposed to alternating sessions of mirror mode and of playback mode. If the dolphin perceives its mirror-mode television image as another dolphin, then whether it is watching mirror mode or playback mode, the dolphin should act the same way - possibly interacting socially with the " television dolphin, " or perhaps just observing it, but behaving the same in both modes. The results for the adult male were clear cut: In mirror mode he spent quite a bit of time opening his mouth wide and moving his head in various rhythmic ways, whereas he never did this during playback mode. The results for juvenile and babies, however, did not show such clear-cut differences between the viewing modes, although the babies seemed to spend more time in front of the television during mirror mode.

Some of the dolphins who participated in the mirror mark tests were also exposed to the mirror mode-playback test. The video camera was located next to the television, to the dolphins' left, and thus favoured showing the left side when they looked at the television. The dolphins were marked on their right sides to see if they would counter this bias by manoeuvring the marked side into view. Three of the adults used the mirror to visually inspect their bodies where the mark was located. One of the most important results from this research comes from a combination of the mirror mark tests and the television tests. Keola, the only adult to have both tests, behaved significantly differently when the television was in mirror mode as compared to playback mode. His behaviour strongly suggests that he did not perceive the television image as another dolphin in either mode and was not interacting with it " socially." When he was marked with a dot, he immediately positioned himself in front of the mirror so that the mark could have been visible to him and then engaged in rapid, extreme, postures. It is very likely that he was examining his mark. The only reasonable alternative is that he might have been posturing socially to what he believed to be another dolphin in the mirror. Since this " social" explanation is rendered not very likely by the television tests, the data suggest that this dolphin examined his mark in the mirror during his mark test, and took his mirror image to be himself.

No single test proves self-recognition in bottlenose dolphins. The tests were developed mainly from primate research paradigms, and their limitations for interpretations of dolphin behaviour are apparent. Nevertheless, the data taken together make a compelling case for self-recognition in this species.

There are some specific limitations that interference mirror use in animals. For example, although at least one specific Gorilla, Koko, has passed this test (Patterson and Cohn, 1994), several others have not (Shillito et al., 1999). This is probably because gorillas consider eye contact an aggressive gesture and normally try to avoid looking each other in the face. At the same time it is worth to note that not all chimpanzees show evidence of mirror self-recognition (Swartz et al., 1999). Above, negative results with mirror self-recognition in apes and elephants may be ascribable to small samples. There is also debate as to the value of the test as applied to animals that rely primarily on senses other than vision, such as dogs.

It is important to note that relative weakness of mirror self-recognition experimental paradigm can be attributed to that researchers often take an all-or-nothing view of self-awareness without considering intermediate stages. DeWaal and colleagues (2005) have elaborated experimental tests that allow demonstrating capuchin monkeys as possibly being able to reach a level of self–other distinction intermediate between seeing their mirror image as another being and recognizing it as self. Members of relatively large groups of capuchins were tested, and researchers used monkey’s social inter-relations in their experiment. They formalized scenarios of monkeys’ contacts with friendly, hostile and unfamiliar conspecifics as well as with mirror reflections. During series of tests each capuchin entered a test chamber, where it was presented with three different situations. In the first one, the monkey saw an unfamiliar monkey of the same sex on the other side of a glass barrier and behind a mesh screen. In the second scenario, the capuchin saw a monkey of the same sex that it was familiar with. Finally, it confronted its own reflection in a mirror behind the screen (Fig. X-12). When capuchins saw another monkey they behaved quite naturally, for example, when meeting with an unfamiliar partner, males made threatening gestures, and females looked nervous and avoided eye contact. Instead, the reflection got treated as a special phenomenon, generally eliciting curiosity and friendly overtures from females and a mix of distress and fear from males. It is likely that capuchin monkeys possess a greater understanding of the mirror’s illusory qualities than generally assumed (deWaal et al., 2005).

It is possible that some animals catch differences between behavioural responses from “normal” intruders and illusory ones that are their own mirror reflections. It is likely that treatment if the reflection as a special phenomenon can be attributed to species outside primates. For instance, Oliveira et al. (2005) have shown in their experiments with cichlid fish Oreochromis mossambicus that fighting males react to a mirror-image challenger differently than to a “normal” intruder. In natural situations androgen concentrations are changed under salient social situations.

Decades of various researchers' studies have shown that among fish, birds, and mammals, winners' androgen concentrations surge and losers' dip. These hormonal changes improve or diminish, respectively, an animal's chance of winning its next fight. Moreover, just watching a fight boosts androgens in spectator fish. The finding echoed a study of androgens in sports fans watching soccer or basketball (Oliveira, 2004). However, androgen concentrations are not increased in fishes that are fighting their own image in a mirror, despite their explicit aggressive behaviour towards the virtual intruder. These results indicate that the hormonal response normally triggered in male contests is not induced by signals delivered by a mirror-image challenger. This enable us to hypothesise that the male fish perceives it’s mirror reflection as something differing from “another fish”.

Recently Bard et al. (2006) integrated approaches of developmental and comparative psychologists concerning the mirror test. They refer to Piagettian developmental stages (see Chapter 13). Stage 6 in object permanence would suggest that the self is conceived as something permanent in time and space. The mirror test shows, additionally, that self can exist and can be represented: the mirror image of the self is a representation of the self as an iconic symbol. Bard et al. (2006) suggest that passing of the mark test is based on being able to concurrently represent the self in multiple forms: the acting self is understood to exist at the same time as the visually reflected acting self in the mirror, an iconic symbolic capacity. So, as the authors give this, mirror-self recognition may be based on specific aspects of mental representation, the cognitive ability to symbolise. It has been revealed in the cited study that when comparable testing procedures and assessment criteria are used, chimpanzees and human infants perform comparably.

The exact nature of animal awareness about selves is not yet resolved by experiments, and results of mirror tests, although sophisticated, do not fully reflect their mental states. In humans, mirror recognition is only a precursor to a continually developing capacity for self-awareness and self-evaluation. Paraphrasing the title of Nigel’s (1974) paper “What is it like to be a bat? ” we can admit that we do not know what it is like to be a conscious non-human animal.

A Russian psychologist Lev Vygotsky (1962) showed that a significant moment in the development of the human individual occurs when language and practical intelligence converge. It is when thought and speech come together that children's thinking is raised to new heights and they start acquiring truly human characteristics. Language becomes a tool of thought allowing children increasingly to master their own behaviour.

Results obtained on language-trained apes can expand our knowledge of awareness in animals. For example, when a bonobo Kanzi was taught a sign for himself and a sign for “bad” and then was shown the two signs together, the bonobo was visibly distressed. This is likely to indicate self-awareness because neither sign alone had such an effect (Savage-Rumbaugh and Lewin, 1994).

CONCLUDING COMMENTS

Development of ethology, a science that is rooted in the observation of animal behaviour has helped researchers to understand that animals use cognition in the natural environment. In nature animals confront problems that differ markedly from one niche to another, and they exhibit intelligence best when it serves their own purposes rather than when the experimenters expect them to do. To navigate social landscape, animals need a surplus of intelligence that overcomes the immediate survival needs, such as eating, avoiding predators, feeding offspring, etc., and this surplus intelligence might have been advantageous for social manipulation, deception and cooperation.

There is much work to be done to evaluate the role of intelligence in maintaining cooperative behaviour. We can assume that cooperation that is based on reciprocal altruism requires more advanced cognitive skills than altruism towards kin because reciprocity demands remembering and discounting levels of cooperativeness among individuals. Specific cognitive adaptations can be expected in some species such as specific concentration of attention and calculation of mutual aids.

Only recently cognitive ethologists have selected species for their experiments taking into account specific sociality. There is a growing body of evidence that highly social animals are more adept at classifying items according to their relative relations, making abstract discriminations about relations between relations, forming concepts about relations between objects independently of their physical features as well as concepts of numerosity and transivity. With reference to data on social learning and information transferring in animals that were considered in Parts VIII and IX, we should expect that members of group living species have more opportunities to learn during their life time than more solitary animals.

However, we should not expect to find a linear correlation between social complexity and levels of intelligence in non-human species. Although experiments based on pair comparison of intellectual abilities in group- and solitary living species have brought some positive results, we should take into consideration that animals that live solitary in complex and risky environment relay on their own memory and learning skills and may enjoy freedom of restrictions and obligations imposed upon them by their possibly narrow roles within a community.

In general, our understanding of animal intelligence will improve with great strides if experimenters arm themselves with knowledge about evolutionary histories and characteristics of niches of the species in hand as well of their sensory equipment, inherited predisposition for particular types of learning, and sociality.

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