This post goes through the lecture by Peter Watts, expanding on the references he makes.
In front of a mirror, and consequently of their reflection view, ants behaved otherwise than when in front of nestmates seen through a glass. Seeing nestmates through a glass, ants behaved as usual, i.e. without taking close notice of them. In front of a mirror, they rapidly moved their head and antennae, to the right and the left, touched the mirror, went away from it and stopped, cleaning then sometimes their legs and antennae. As long as they could not see themselves in a mirror, ants with a blue dot painted on their clypeus did not try to remove it. Set in front of a mirror, ants with such a blue dot on their clypeus tried to clean themselves, while ants with a brown painted dot ‒ of the same color as that of their cuticle ‒ on their clypeus and ants with a blue dot on their occiput did not clean themselves. Very young ants did not present such behavior. Contrary to the other kinds of marking, a blue dot on the clypeus induced aggressiveness in nestmates. The front part of the head is thus an essential species specific character for leading to acceptance. Although further experiments are required, preferentially on ants and social hymenoptera with an excellent visual perception, our observations suggest that some ants can recognize themselves when confronted with their reflection view, this potential ability not necessary implicating some self awareness.
Order in Spontaneous Behavior (2007)
Brains are usually described as input/output systems: they transform sensory input into motor output. However, the motor output of brains (behavior) is notoriously variable, even under identical sensory conditions. The question of whether this behavioral variability merely reflects residual deviations due to extrinsic random noise in such otherwise deterministic systems or an intrinsic, adaptive indeterminacy trait is central for the basic understanding of brain function. Instead of random noise, we find a fractal order (resembling Lévy flights) in the temporal structure of spontaneous flight maneuvers in tethered Drosophila fruit flies. Lévy-like probabilistic behavior patterns are evolutionarily conserved, suggesting a general neural mechanism underlying spontaneous behavior. Drosophila can produce these patterns endogenously, without any external cues. The fly's behavior is controlled by brain circuits which operate as a nonlinear system with unstable dynamics far from equilibrium. These findings suggest that both general models of brain function and autonomous agents ought to include biologically relevant nonlinear, endogenous behavior-initiating mechanisms if they strive to realistically simulate biological brains or out-compete other agents.
The capacity to adapt to resource distributions by modulating the frequency of exploratory and exploitative behaviors is common across metazoans and is arguably a principal selective force in the evolution of cognition. Here we (1) review recent work investigating behavioral and biological commonalities between external foraging in space and internal foraging over environments specified by cognitive representations, and (2) explore the implications of these commonalities for understanding the origins of the self. Behavioural commonalities include the capacity for what is known as area-restricted search in the ecological literature: this is search focussed around locations where resources have been found in the past, but moving away from locations where few resources are found, and capable of producing movement patterns mimicking Lévy flights. Area-restricted search shares a neural basis across metazoans, and these biological commonalities in vertebrates suggest an evolutionary homology between external and internal foraging. Internal foraging, and in particular a form we call embodied prospective foraging, makes available additional capacities for prediction based on search through a cognitive representation of the external environment, and allows predictions about outcomes of possible future actions. We demonstrate that cognitive systems that use embodied prospective foraging require a primitive sense of self, needed to distinguish actual from simulated action. This relationship has implications for understanding the evolution of autonoetic consciousness and self-awareness.
Integrated information theory: from consciousness to its physical substrate (2016)
In this Opinion article, we discuss how integrated information theory accounts for several aspects of the relationship between consciousness and the brain. Integrated information theory starts from the essential properties of phenomenal experience, from which it derives the requirements for the physical substrate of consciousness. It argues that the physical substrate of consciousness must be a maximum of intrinsic cause–effect power and provides a means to determine, in principle, the quality and quantity of experience. The theory leads to some counterintuitive predictions and can be used to develop new tools for assessing consciousness in non-communicative patients.
Morsella's theory of consciousness is new to me. Basically, a body has many control subroutines, each with its own goals and computational devices. Consciousness is used to make a choice when they disagree about their plans for the body to move. From The Function of Phenomenal States: Supramodular Interaction Theory (2005):
What insects can tell us about the origins of consciousness (2016)Discovering the function of phenomenal states remains a formidable scientific challenge. Research on consciously penetrable conflicts (e.g., "pain-for-gain" scenarios) and impenetrable conflicts (as in the pupillary reflex, ventriloquism, and the McGurk effect [H. McGurk & J. MacDonald, 1976]) reveals that these states integrate diverse kinds of information to yield adaptive action. Supramodular interaction theory proposes that phenomenal states play an essential role in permitting interactions among supramodular response systems--agentic, independent, multimodal, information-processing structures defined by their concerns (e.g., instrumental action vs. certain bodily needs). Unlike unconscious processes (e.g., pupillary reflex), these processes may conflict with skeletal muscle plans, as described by the principle of parallel responses into skeletal muscle (PRISM). Without phenomenal states, these systems would be encapsulated and incapable of collectively influencing skeletomotor action.
How, why, and when consciousness evolved remain hotly debated topics. Addressing these issues requires considering the distribution of consciousness across the animal phylogenetic tree. Here we propose that at least one invertebrate clade, the insects, has a capacity for the most basic aspect of consciousness: subjective experience. In vertebrates the capacity for subjective experience is supported by integrated structures in the midbrain that create a neural simulation of the state of the mobile animal in space. This integrated and egocentric representation of the world from the animal’s perspective is sufficient for subjective experience. Structures in the insect brain perform analogous functions. Therefore, we argue the insect brain also supports a capacity for subjective experience. In both vertebrates and insects this form of behavioral control system evolved as an efficient solution to basic problems of sensory reafference and true navigation. The brain structures that support subjective experience in vertebrates and insects are very different from each other, but in both cases they are basal to each clade. Hence we propose the origins of subjective experience can be traced to the Cambrian.
The Cambridge declaration on consciousness (2012)
The absence of a neocortex does not appear to preclude an organism from experiencing affective states. Convergent evidence indicates that non-human animals have the neuroanatomical, neurochemical, and neurophysiological substrates of conscious states along with the capacity to exhibit intentional behaviors. Consequently, the weight of evidence indicates that humans are not unique in possessing the neurological substrates that generate consciousness. Nonhuman animals, including all mammals and birds, and many other creatures, including octopuses, also possess these neurological substrates.
Building an organic computing device with multiple interconnected brains (2015)
Recently, we proposed that Brainets, i.e. networks formed by multiple animal brains, cooperating and exchanging information in real time through direct brain-to-brain interfaces, could provide the core of a new type of computing device: an organic computer. Here, we describe the first experimental demonstration of such a Brainet, built by interconnecting four adult rat brains. Brainets worked by concurrently recording the extracellular electrical activity generated by populations of cortical neurons distributed across multiple rats chronically implanted with multi-electrode arrays. Cortical neuronal activity was recorded and analyzed in real time, and then delivered to the somatosensory cortices of other animals that participated in the Brainet using intracortical microstimulation (ICMS). Using this approach, different Brainet architectures solved a number of useful computational problems, such as discrete classification, image processing, storage and retrieval of tactile information, and even weather forecasting. Brainets consistently performed at the same or higher levels than single rats in these tasks. Based on these findings, we propose that Brainets could be used to investigate animal social behaviors as well as a test bed for exploring the properties and potential applications of organic computers.
On Making the Right Choice: The Deliberation-Without-Attention Effect (2006):
Contrary to conventional wisdom, it is not always advantageous to engage in thorough conscious deliberation before choosing. On the basis of recent insights into the characteristics of conscious and unconscious thought, we tested the hypothesis that simple choices (such as between different towels or different sets of oven mitts) indeed produce better results after conscious thought, but that choices in complex matters (such as between different houses or different cars) should be left to unconscious thought. Named the “deliberation-without-attention” hypothesis, it was confirmed in four studies on consumer choice, both in the laboratory as well as among actual shoppers, that purchases of complex products were viewed more favorably when decisions had been made in the absence of attentive deliberation.
The famous Libet experiment, greatly expanded. Unconscious determinants of free decisions in the human brain (2008):
There has been a long controversy as to whether subjectively 'free' decisions are determined by brain activity ahead of time. We found that the outcome of a decision can be encoded in brain activity of prefrontal and parietal cortex up to 10 s before it enters awareness. This delay presumably reflects the operation of a network of high-level control areas that begin to prepare an upcoming decision long before it enters awareness.
Consciousness and its function (2007), on how consciousness is a nonadaptive side effect of other processes.
It is plain that an individual’s being conscious and an individual’s being conscious of various things are both crucial for successful functioning. But it is far less clear how, if at all, it is also useful for a person’s psychological states to occur consciously, as against those states occurring but without being conscious. Restricting attention to cognitive and desiderative states, a number of suggestions are current about how the consciousness of those states may be useful. It has been held that such consciousness enhances processes of rational thought and planning, intentional action, executive function, and the correction of complex reasoning. I examine these and related proposals in the light of various empirical findings and theoretical considerations and conclude that the consciousness of cognitive and desiderative states is unlikely to be useful in these or related ways. This undermines a reliance on evolutionary selection pressures in explaining why such states so often occur consciously in humans. I propose an alternative explanation, on which cognitive and desiderative states come to be conscious as a result of other highly useful psychological developments, some involving language. But on this explanation the consciousness of these states itself adds no significant function to that of those other developments.
The consciousness of thoughts, desires, and volitions adds little if any benefit for rational thinking, intentional action, executive function, or complex reasoning. Nonetheless, an explanation is available of why those states are often conscious that makes no appeal to beneficial effects or evolutionary adaptive value.
A cortical neural prosthesis for restoring and enhancing memory (2011)
A primary objective in developing a neural prosthesis is to replace neural circuitry in the brain that no longer functions appropriately. Such a goal requires artificial reconstruction of neuron-to-neuron connections in a way that can be recognized by the remaining normal circuitry, and that promotes appropriate interaction. In this study, the application of a specially designed neural prosthesis using a multi-input/multi-output (MIMO) nonlinear model is demonstrated by using trains of electrical stimulation pulses to substitute for MIMO model derived ensemble firing patterns. Ensembles of CA3 and CA1 hippocampal neurons, recorded from rats performing a delayed-nonmatch-to-sample (DNMS) memory task, exhibited successful encoding of trial-specific sample lever information in the form of different spatiotemporal firing patterns. MIMO patterns, identified online and in real-time, were employed within a closed-loop behavioral paradigm. Results showed that the model was able to predict successful performance on the same trial. Also, MIMO model-derived patterns, delivered as electrical stimulation to the same electrodes, improved performance under normal testing conditions and, more importantly, were capable of recovering performance when delivered to animals with ensemble hippocampal activity compromised by pharmacologic blockade of synaptic transmission. These integrated experimental-modeling studies show for the first time that, with sufficient information about the neural coding of memories, a neural prosthesis capable of real-time diagnosis and manipulation of the encoding process can restore and even enhance cognitive, mnemonic processes.
Developing a hippocampal neural prosthetic to facilitate human memory encoding and recall (2018)
Objective. We demonstrate here the first successful implementation in humans of a proof-of-concept system for restoring and improving memory function via facilitation of memory encoding using the patient's own hippocampal spatiotemporal neural codes for memory. Memory in humans is subject to disruption by drugs, disease and brain injury, yet previous attempts to restore or rescue memory function in humans typically involved only nonspecific, modulation of brain areas and neural systems related to memory retrieval. Approach. We have constructed a model of processes by which the hippocampus encodes memory items via spatiotemporal firing of neural ensembles that underlie the successful encoding of short-term memory. A nonlinear multi-input, multi-output (MIMO) model of hippocampal CA3 and CA1 neural firing is computed that predicts activation patterns of CA1 neurons during the encoding (sample) phase of a delayed match-to-sample (DMS) human short-term memory task. Main results. MIMO model-derived electrical stimulation delivered to the same CA1 locations during the sample phase of DMS trials facilitated short-term/working memory by 37% during the task. Longer term memory retention was also tested in the same human subjects with a delayed recognition (DR) task that utilized images from the DMS task, along with images that were not from the task. Across the subjects, the stimulated trials exhibited significant improvement (35%) in both short-term and long-term retention of visual information. Significance. These results demonstrate the facilitation of memory encoding which is an important feature for the construction of an implantable neural prosthetic to improve human memory.
Visual cortical prosthesis with a geomagnetic compass restores spatial navigation in blind rats (2015)
Allocentric sense is one of the major components that underlie spatial navigation [1, 2]. In blind patients, the difficulty in spatial exploration is attributed, at least partly, to the deficit of absolute direction perception. In support of this notion, we announce that blind adult rats can perform spatial tasks normally when externally provided with real-time feedback of their head directions. Head-mountable microstimulators coupled with a digital geomagnetic compass were bilaterally implanted in the primary visual cortex of adult rats whose eyelids had been sutured. These “blind” rats were trained to seek food pellets in a T-shaped maze or a more complicated maze. Within tens of trials, they learned to manage the geomagnetic information source to solve the mazes. Their performance levels and navigation strategies were similar to those of normal sighted, intact rats. Thus, blind rats can recognize self-location through extrinsically provided stereotactic cues.
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