Consciousness

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From a veterinary perspective, consciousness must be imputed in all animals not only for ethical reasons associated with animal experimentation[1], animal hunting and legitimate culling, but also for a holistic approach to pain management, anxiolysis, abolition of stress and maximisation of welfare. Therefore, a scientific paradigm for animal consciousness must be defined for the ethical treatment of non-human animals[2]. Failure to do so leaves animals ethically vulnerable to maltreatment under the guise of religious or cultural determinants that see nonhuman consciousness as inferior, arbitrary or nonexistent.

The science of consciousness (cognition) is termed metacognition, which is an umbrella term that encompasses a computational ability to be self-aware, self-organising and maintaining a self-referential check and balance on conscious states based on memory, reasoning and deductive analysis[3]. This definition makes no assumtion that metacognition requires neuronal activity, since artifical intelligence has a higher referental states of metacognition compared for example to decerebrate experimental rats. Metacognition equates to self-awareness, be that consciousness natural or artificial, animal or plant, human or nonhuman[4].

Though animals appear to have varying capacitites for metacognition compared with the human model, their cognitive states cannot be easily dismissed, based on evidence of animal's ability to problem solve, comprehend and anticipate or fear temporal events and a myriad of other cognitive events which humans take for granted[5]. To judge nonhuman cognitive skills as inferior is fraught with ethical dangers, as an equally-valued judgement can be made with intellectually impaired humans, a judgement no ethical scientist wishes to ever make. It must therefore be concluded that metacognition per se is inherent in all living things, and that consciousness be valued in and of itself, regardless of the form and content of that cognitive state.

Consciousness is attributed to animals as a general rule. The 'quality' of animal consciousness varies enormously. Awareness may be merely sensorial, such as single-celled organisms aware of molecular changes in its immediate environment, to mammals hibernating in response to shortening daylengths.

Varying states of consciousness have been defined in the veterinary literature, pertaining in particular to its depth under anesthesia or sedation, as well as a tool for assessing efficacy of pharmeutical modalities in pain-relief, anxiolysis, fear and aggression management and termination by euthanasia.

The importance of animal consciousness is contentious, with some scientist lending to a state of empiric awareness but without anthropological relevance - 'an animal's mind is a thing as opposed to a soul or something similarly unique to humanoid consciousness.' Our ability to abstract, create and articulate remain the reference points of consciousness.

Other less-pragmatic scientists have developed a more holistic approach, appending consciousness to animals, plants and minerals with the only distinction being the sensorial intepretation of that conscious state. For example, Penrose and Hameroff have proposed that consciousness may be viewed as a fundamental problem in quantum physics. Specifically, their 'orchestrated objective reduction' (Orch-OR) hypothesis posits that conscious states arise from quantum computations in the microtubules of neurons. They argue therefore that because these proteins can be found in both plant and animal cells, some form of consciousness must be attribute to that kingdom[6].

What is consciousness?

Consciousness is an emergent phenomenon which arises secondarily from interconnected neural activity.

It can be defined as an evolving state of heuristic spatio-temporal communicative self-awareness[7]. Simply put, consciousness is an awareness of one's cognitive (thought) states. To be aware of somatic (one's body) states is colloquially referred to as sentience. Thus sentience does not necessarily infer consciousness per se and is a less accurate term. The classic example which clarifies the difference is observed in nonsentient humans ('locked-in' syndrome) where they are somatically insensate but consciously aware, verified by trained visual cues[8].

Consciousness is driven, at least in humans, by five primary emotions which affect neocortical functions: fear, anger, disgust, surprise, and happiness/sadness[9]. In higher animals, these enotional states can be visualised through body language to be intact and highly ordered. Levels of consciousness can thus be determined by the form and content of memory, emotions, spatiotemporal recognition, language (both verbal and somatic) and self- and nonself-recognition. An example of varying degrees of consciousness can be observed with invertebrates which respond sentiently in an heuristic manner to painful external stumuli and recognize self from nonself. However, their state of consciousness is as yet undetermined[10], as the methods to impute consciousness are currently unavailable. This does not however preclude their possessing some form of consciousness.

In higher order animals, consciousness manifests essentially as a hologram-like feature (depictive representation)[11] due to pulse-like synchronous waves of electrochemical bursts within the visual, tactile, olfactory and auditory sensory cortices[12]. This holographic feature of consciousness is thought to be created via the outermost layer of the cerebral cortex, which can be compared to the surface of a pond, on which electrical signals travel and interfere with one another in the holographic mode to convert the neuroelectric patterns on its surface into virtual images and thoughts[13].

Consciousness cannot be readily localized by experimentation. Although neuronal activity through functional MRI (fMRI) and EEGs can allude to parts of the brain that are active while thinking, they do not correlate accurately with what is being sensed within the sensorial hologram created by conscious states. The quantum-like and holographic properties (i.e. parts elicit wholes) of self-aware consciousness are readily colored by personality, culture and experience in humans, and similar differences are observed in specifics such as breed-variability of equine temperaments, breed reactivity in cats to certain stimuli such as water.

That consciousness can be effected by genetic changes or mutations suggests a genetic base or epigenetic modulation to self-awareness. It appears to be more than mere neuronal activity within the central nervous system[14]. Spontaneous neuronal rhythm measured using EEG evince endogenous patterns of connectivity and synchronicity underlying states of attention, perception, and consciousness[15].

Two major factors important in the measurement of consciousness in animals are microtubule function and electrical gamma wave synchrony, as determined by microelectrode and EEG studies[16]. These features are important for memory associated with consciousness. It is believed that these epigenetics determinants (microtubule function and gamma wave synchorny) are critical for long-term cell memory consolidation and cognitive matching of cell memory to experience during consciousness[17].

The prevailing neuroscientific paradigm regarding consciousness is that there is an organized and interconnected neural network which incorporates subcellular mechanisms down to the genetic level, making available vastly greater number of neurochemical interactions, numbering in the 1012 connections, matching quantum levels of interconnections[18]. Signal nonlocality, accessed by means of quantum entanglement is an essential feature of this subcellular quantum-like nature of consciousness[19].

Self- and nonself-awareness has been demonstrated to varying degrees in all animals and is a nonstatic state that changes under environmental[20] and biological stress[21][22], which mould neuronal plasticity[23]. In most animals, including humans, consciousness is believed to be essentially an emergent phenomenon of sensory activity. Consciousness emerges or arises as a secondary effect in and of itself, that requires sensory awareness, but is not implicated by sensory abilities. For example, a knee-jerk reflex requires sensory and motor activity but does not imply any conscious state.

In human parlance, states of consciousness are never more critical than determining permanent loss of 'self' as a statutory definition of death[24]. Excluding artificial intelligence, sensory activity (sentience) is usually limited to neurochemical activity within the central nervous system, and death is defined as a permanent loss of sensory-based consciousness with a reversion to a vegetative insensate state[25].

References

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