Biological nonlocality and the mind-brain interaction problem: comments on a new empirical approach

Up to now, we have been faced with an age old fundamental dilemma posed by the mind-brain interaction problem, i.e. how is it that the mind which is subjective and immaterial, can interact with the brain which is objective and material? Analysis of recent experiments appears to indicate that quantum mechanics may have a role to play in the resolution of the mind-brain interaction problem in the form of biological entanglement and nonlocality. In addition to this analysis, when coupled with ongoing and proposed experiments, may help us to simultaneously resolve related issues such as whether mental events can initiate neural events, the transference of conscious subjective experience, the measurement problem and the binding problem.     

Subjective antedating of a sensory experience and mind-brain theories: reply to Honderich (1984)

Honderich claims that our "delay-and-antedating" hypothesis, of a delay in cerebral production combined with a subjective antedating of a conscious sensory experience, involves self-contradiction which may cast doubt on some of our experimental findings and on the hypothesis. This claim misses the distinction between the phenomenological subjective mental content of an experience and the physical-neuronal configuration that elicits the experience; also, it cannot explain the experimentally observed discrepancy, between subjective timing and the empirically delayed time for cerebral adequacy for eliciting the experience, found when stimulating a subcortical sensory pathway. Honderich usefully distinguishes between our stated (delay-and-antedating) hypothesis and a different though unacceptable one which would have serious implications for mind-brain theories. The delay-and-antedating hypothesis does not provide a formally definitive contradiction of monist-identity theory (of the mind-brain relationship). However, our experimentally based hypothesis does dissociate subjective/mental timing from the actual physical/neuronal time of an experience. This phenomenon, though conceptually strange, must be encompassed by any mind-brain theory.     

A unitary hypothesis of mind-brain interaction in the cerebral cortex

A brief introduction to the brain-mind problem leads on to a survey of the neuronal structure of the cerebral cortex. It is proposed that the basic receptive units are the bundles or clusters of apical dendrites of the pyramidal cells of laminae V and III-II as described by Fleischhauer and Peters and their associates. There are up to 100 apical dendrites in these receptive units, named dendrons. Each dendron would have an input of up to 100,000 spine synapses. There are about 40 million dendrons in the human cerebral cortex. A study of the influence of mental events on the brain leads to the hypothesis that all mental events, the whole of the World 2 of Popper, are composed of mental units, each carrying its own characteristic mental experience. It is further proposed that each mental unit, named psychon, is uniquely linked to a dendron. So the mind-brain problem reduces to the interaction between a dendron and its psychon for all the 40 million linked units. In my 1986 paper (Proc. R. Soc. Lond. B 227, 411-428) on the mind-brain problem, there was developed the concept that the operation of the synaptic microsites involved displacement of particles so small that they were within range of the uncertainty principle of Heisenberg. The psychon-dendron interaction provides a much improved basis for effective selection by a process analogous to a quantal probability field. In the fully developed hypothesis psychons act on dendrons in the whole world of conscious experiences and dendrons act on psychons in all perceptions and memories. It is shown how these interactions involve no violation of the conservation laws. There are great potentialities of these unitary concepts, for example as an explanation of the global nature of a visual experience from moment to moment. It would seem that there can be psychons not linked to dendrons, but only to other psychons, creating what we may call a psychon world.     

Do mental events cause neural events analogously to the probability fields of quantum mechanics?

If non-material mental events, such as the intention to carry out an action, are to have an effective action on neural events in the brain, it has to be at the most subtle and plastic level of these events. In the first stage of our enquiry an introduction to conventional synaptic theory leads on to an account of the manner of operation of the ultimate synaptic units. These units are the synaptic boutons that, when excited by an all-or-nothing nerve impulse, deliver the total contents of a single synaptic vesicle, not regularly, but probabilistically. This quantal emission of the synaptic transmitter molecules (about 5000-10 000) is the elementary unit of the transmission process from one neuron to another. In the second stage this refined physiological analysis leads on to an account of the ultrastructure of the synapse, which gives clues as to the manner of its unitary probabilistic operation. The essential feature is that the effective structure of each bouton is a paracrystalline presynaptic vesicular grid with about 50 vesicles, which acts probabilistically in vesicular (quantal) release. In the third stage it is considered how a non-material mental event, such as an intention to move, could influence the subtle probabilistic operations of synaptic boutons. On the biological side, attention is focused on the paracrystalline presynaptic vesicular grids as the targets for non-material mental events. On the physical side, attention is focused on the probabilistic fields of quantum mechanics which carry neither mass nor energy, but which nevertheless can exert effective action at microsites. The new light on the mind-brain problem came from the hypothesis that the non-material mental events, the 'World 2' of Popper, relate to the neural events of the brain (the 'World 1' of matter and energy) by actions in conformity with quantum theory. This hypothesis that mental events act on probabilistic synaptic events in a manner analogous to the probability fields of quantum mechanics seems to open up an immense field of scientific investigation both in quantum physics and in neuroscience.     

Trial-by-trial predictions of subjective time from human brain activity

Human experience of time exhibits systematic, context-dependent deviations from clock time; for example, time is experienced differently at work than on holiday. Here we test the proposal that differences from clock time in subjective experience of time arise because time estimates are constructed by accumulating the same quantity that guides perception: salient events. Healthy human participants watched naturalistic, silent videos of up to 24 seconds in duration and estimated their duration while fMRI was acquired. We were able to reconstruct trial-by-trial biases in participants’ duration reports, which reflect subjective experience of duration, purely from salient events in their visual cortex BOLD activity. By contrast, salient events in neither of two control regions–auditory and somatosensory cortex–were predictive of duration biases. These results held despite being able to (trivially) predict clock time from all three brain areas. Our results reveal that the information arising during perceptual processing of a dynamic environment provides a sufficient basis for reconstructing human subjective time duration.     

Sensory adaptation for timing perception

Recent sensory experience modifies subjective timing perception. For example, when visual events repeatedly lead auditory events, such as when the sound and video tracks of a movie are out of sync, subsequent vision-leads-audio presentations are reported as more simultaneous. This phenomenon could provide insights into the fundamental problem of how timing is represented in the brain, but the underlying mechanisms are poorly understood. Here, we show that the effect of recent experience on timing perception is not just subjective; recent sensory experience also modifies relative timing discrimination. This result indicates that recent sensory history alters the encoding of relative timing in sensory areas, excluding explanations of the subjective phenomenon based only on decision-level changes. The pattern of changes in timing discrimination suggests the existence of two sensory components, similar to those previously reported for visual spatial attributes: a lateral shift in the nonlinear transducer that maps relative timing into perceptual relative timing and an increase in transducer slope around the exposed timing. The existence of these components would suggest that previous explanations of how recent experience may change the sensory encoding of timing, such as changes in sensory latencies or simple implementations of neural population codes, cannot account for the effect of sensory adaptation on timing perception.     

On the epistemology of mental illness.

The most important epistemological problem in psychiatry is the detection of malingering. This is a consequence of the fact that there is no objective way to confirm any psychiatric diagnosis. Psychiatric diagnosis is based on subjective complaints. The discovery of objective markers for psychiatric diagnosis is problematic because it presupposes we can tell valid from faked subjective symptoms. But this is the difficulty. If we use pervasive irrationality as a sign of mental illness, we encounter the problem of identifying pervasive irrationality. To understand someone's behaviour, we have to assume it is largely rational. This precludes us from using behaviour to separate genuine from faked mental illness. There are a number of strategies used to solve any epistemological problem, and the most successful is the hypothetico-deductive method. If we use this, we can solve our epistemological problem. Genuine mental illness can be identified when it is the best explanation of the person's overall behaviour. Consilience of inductions is critical in supporting the validity of such explanations. This implies that it is merely a hypothesis that mental illness exists, and that we might discover that many mental illnesses, perhaps all, do not exist. We must embrace this possibility--only if we take a risk will we gain any knowledge.     

The human amygdala and orbital prefrontal cortex in behavioural regulation

Survival in complex environments depends on an ability to optimize future behaviour based on past experience. Learning from experience enables an organism to generate predictive expectancies regarding probable future states of the world, enabling deployment of flexible behavioural strategies. However, behavioural flexibility cannot rely on predictive expectancies alone and options for action need to be deployed in a manner that is responsive to a changing environment. Important moderators on learning-based predictions include those provided by context and inputs regarding an organism's current state, including its physiological state. In this paper, I consider human experimental approaches using functional magnetic resonance imaging that have addressed the role of the amygdala and prefrontal cortex (PFC), in particular the orbital PFC, in acquiring predictive information regarding the probable value of future events, updating this information, and shaping behaviour and decision processes on the basis of these value representations.     

Experimental and theoretical approaches to conscious processing

Recent experimental studies and theoretical models have begun to address the challenge of establishing a causal link between subjective conscious experience and measurable neuronal activity. The present review focuses on the well-delimited issue of how an external or internal piece of information goes beyond nonconscious processing and gains access to conscious processing, a transition characterized by the existence of a reportable subjective experience. Converging neuroimaging and neurophysiological data, acquired during minimal experimental contrasts between conscious and nonconscious processing, point to objective neural measures of conscious access: late amplification of relevant sensory activity, long-distance cortico-cortical synchronization at beta and gamma frequencies, and "ignition" of a large-scale prefronto-parietal network. We compare these findings to current theoretical models of conscious processing, including the Global Neuronal Workspace (GNW) model according to which conscious access occurs when incoming information is made globally available to multiple brain systems through a network of neurons with long-range axons densely distributed in prefrontal, parieto-temporal, and cingulate cortices. The clinical implications of these results for general anesthesia, coma, vegetative state, and schizophrenia are discussed.     

The Semantic Representation of Event Information Depends on the Cue Modality: An Instance of Meaning-Based Retrieval

The semantic content, or the meaning, is the essence of autobiographical memories. In comparison to previous research, which has mainly focused on the phenomenological experience and the age distribution of retrieved events, the present study provides a novel view on the retrieval of event information by quantifying the information as semantic representations. We investigated the semantic representation of sensory cued autobiographical events and studied the modality hierarchy within the multimodal retrieval cues. The experiment comprised a cued recall task, where the participants were presented with visual, auditory, olfactory or multimodal retrieval cues and asked to recall autobiographical events. The results indicated that the three different unimodal retrieval cues generate significantly different semantic representations. Further, the auditory and the visual modalities contributed the most to the semantic representation of the multimodally retrieved events. Finally, the semantic representation of the multimodal condition could be described as a combination of the three unimodal conditions. In conclusion, these results suggest that the meaning of the retrieved event information depends on the modality of the retrieval cues.     

A Contribution to the Problem of the Role of Set and Attitude in Perceptual Processes

Different human beings perceive the same phenomena, events, and things in different ways. This fact, which we encounter at every step in our daily lives and in all spheres of our activity is one of the central problems in the psychology of perception. Observations and experiments have established, beyond question, that past experience is one of the circumstances involved. The first problem studied in this connection was the role of the personality factor in perception. After all, past experience is the property of the personality. The problem of the subjective factor also arose in connection with the fact that psychological activity is generally purposeful, and this is particularly true of the processes of thought and perception. As a matter of fact, it would be no exaggeration to state that the problem of the subjective factor faces all schools of perceptual psychology to one degree or another and in one form or another, no matter how widely their theoretical positions differ.     

An update on the role of brain glutamine synthesis and its relation to cell-specific energy metabolism in the hyperammonemic brain: further studies using NMR spectroscopy

Ammonia is a neurotoxin that is implicated in the pathogenesis of hepatic encephalopathy due to acute and chronic liver failure. However, its relation to neurological damage and brain edema is poorly understood. During the last decades, it has been the prevailing hypothesis that an osmotic disturbance induced by the astrocytic accumulation of glutamine leads to brain edema. However, various findings are at variance with this hypothesis. The present review will discuss: (a) correlation of ammonia with encephalopathy and brain edema in HE; (b) glutamine synthesis and astrocyte swelling; (c) glutamine synthesis and the glutamine-cycle: relation to brain energy metabolism; (d) glutamine synthesis and the glutamate-glutamine cycle and its relation to anaplerotic activity; (e) evidence favouring the "glutamine hypothesis"; (f) evidence contradicting the "glutamine hypothesis"; (g) glutamine synthesis and osmoregulation; (h) glutamine synthesis in chronic liver failure; (i) impaired brain energy metabolism in acute liver failure (ALF) and its relation to astrocytic glutamine synthesis. Taken together, the precise role of glutamine in the development of brain edema in ALF remains unclear. Astrocytic changes due to glutamine accumulation may lead secondarily to effects on brain energy metabolism. However, the relation between impaired energy metabolism and glutamine accumulation has not been well established. It is noteworthy that no single biochemical factor appears to be responsible for the many symptoms of HE. For example, brain glutamine accumulation and low-grade brain edema occur in chronic liver failure (CLF) suggesting common mechanisms are responsible for the neurological dysfunction in CLF and ALF. Recent NMR spectroscopic studies have provided considerably new information in this area. Future NMR studies using the stable isotope 13C may be useful in the study of the dynamics of brain metabolism in patients with ALF so as to better elucidate the precise role of glutamine accumulation and of glutamine-independent components to brain edema in ALF.     

It’s Not My Fault: Postdictive Modulation of Intentional Binding by Monetary Gains and Losses

Sense of agency refers to the feeling that one’s voluntary actions caused external events. Past studies have shown that compression of the subjective temporal interval between actions and external events, called intentional binding, is closely linked to the experience of agency. Current theories postulate that the experience of agency is constructed via predictive and postdictive pathways. One remaining problem is the source of human causality bias; people often make misjudgments on the causality of voluntary actions and external events depending on their rewarding or punishing outcomes. Although human causality bias implies that sense of agency can be modified by post-action information, convincing empirical findings for this issue are lacking. Here, we hypothesized that sense of agency would be modified by affective valences of action outcomes. To examine this issue, we investigated how rewarding and punishing outcomes following voluntary action modulate behavioral measures of agency using intentional binding paradigm and classical conditioning procedures. In the acquisition phase, auditory stimuli were paired with positive, neutral or negative monetary outcomes. Tone-reward associations were evaluated using reaction times and preference ratings. In the experimental session, participants performed a variant of intentional binding task, where participants made timing judgments for onsets of actions and sensory outcomes while playing simple slot games. Our results showed that temporal binding was modified by affective valences of action outcomes. Specifically, intentional binding was attenuated when negative outcome occurred, consistent with self-serving bias. Our study not only provides evidence for postdictive modification of agency, but also proposes a possible mechanism of human causality bias.     

跨通道迁移及其认知神经机制

跨通道迁移是指将在一种感觉通道获得的知识应用于另一感觉通道的能力。跨通道迁移的相关研究探索了大脑表征不同感觉通道信息的方式,为减少重复学习、提高认知加工效率提供了新的见解。为较好地概括跨通道迁移的特点和机制,本文首先介绍了在物体识别、类别学习和时间知觉等不同领域对跨通道迁移效应的实验研究,之后介绍了支持跨通道迁移的表征类型和相关理论,梳理了跨通道迁移产生的理论及采用事件相关电位（ERP）和功能磁共振成像（fMRI）等技术探讨跨通道迁移神经机制的研究进展,并指出了影响跨通道迁移的因素。最后,对目前跨通道迁移研究成果及其潜在应用进行了总结,并对这一领域未来的研究问题进行了展望。     

Brain microdialysis and its applications in experimental neurochemistry

Microdialysis is one of the most powerful neurochemistry techniques, which allows the monitoring of changes in the extracellular content of endogenous and exogenous substances in the brain of living animals. The strength as well as wide applicability of this experimental approach are based on the bulk theory of brain neurotransmission. This methodological review introduces basic principles of chemical neurotransmission and emphasizes the difference in neurotransmission types. Clear understanding of their significance and degree of engagement in regulation of physiological processes is an ultimate prerequisite not only for choosing an appropriate method of monitoring for interneuronal communication via chemical messengers but also for accurate data interpretation. The focus on the processes of synthesis/metabolism, receptor interaction/ neuronal signaling or the behavioral relevance of neurochemical events sculpts the experiment design. Brain microdialysis is an important method for examining changes in the content of any substances, irrespective of their origin, in living animals. This article compares contemporary approaches and techniques that are used for monitoring neurotransmission (including in vivo brain microdialysis, voltammetric methods, etc). We highlight practical aspects of microdialysis experiments in particular to those researchers who are seeking to increase the repertoire of their experimental techniques with brain microdialysis.     

Human brain reflexes: from stimulus to recognition and from decision to action

The paper presents a survey of the data, obtained in laboratories, directed by the author, on the problem of the brain bases of psychics. Phenomena of perception, thinking and taking decision about behavioural response correspond to the afferent, central and efferent parts of the reflex arch. Psychic function arises on the basis of complex organization and integration of the processes in the brain. It is shown that sensation is based on the synthesis in the cortical projection area of the information on physical and signal properties of the stimulus. By means of the method developed in the laboratory, of mapping of intracortical interaction the participation is studied of different cortical zones in the process of mental creation of visual image. The process of taking decision is studied by a new method: "reaction choice potential" recorded in the case of decision, about the character of reaction to signal controlled by consciousness.     

Fuzzy ART-based place recognition for visual loop closure detection

The automatic place recognition problem is one of the key challenges in SLAM approaches for loop closure detection. Most of the appearance-based solutions to this problem share the idea of image feature extraction, memorization, and matching search. The weakness of these solutions is the storage and computational costs which increase drastically with the environment size. In this regard, the major constraints to overcome are the required visual information storage and the complexity of similarity computation. In this paper, a novel formulation is proposed that allows the computation time reduction while no visual information are stored and matched explicitly. The proposed solution relies on the incremental building of a bio-inspired visual memory using a Fuzzy ART network. This network considers the properties discovered in primate brain. The performance evaluation of the proposed method has been conducted using two datasets representing different large scale outdoor environments. The method has been compared with RatSLAM and FAB-MAP approaches and has demonstrated a decreased time and storage costs with broadly comparable precision recall performance.     

Control of mental activities by internal models in the cerebellum

The intricate neuronal circuitry of the cerebellum is thought to encode internal models that reproduce the dynamic properties of body parts. These models are essential for controlling the movement of these body parts: they allow the brain to precisely control the movement without the need for sensory feedback. It is thought that the cerebellum might also encode internal models that reproduce the essential properties of mental representations in the cerebral cortex. This hypothesis suggests a possible mechanism by which intuition and implicit thought might function and explains some of the symptoms that are exhibited by psychiatric patients. This article examines the conceptual bases and experimental evidence for this hypothesis.     

Neural mechanisms of memory: synaptic and genomic hypotheses

Memorizing of new facts and events means that entering signals produce definite changes within the brain. According to the commonly accepted hypothesis, traces of memory are stored through modifications in the strength of synaptic connections, resulting in formations of new patterns of neural activity. This synaptic hypothesis of memory determines the main direction of experimental studies in the field. It is shown in this review that the synaptic hypothesis can hardly explain the mechanism of long-term (often life-long) memory storage as well as memory resistance to both uncontrolled synaptic activity (epileptic seizures) and various adverse effects on the brain (anesthesia, injury, concussion, etc.). Arguments for an alternative hypothesis are given that long-term memory is mainly formed at the intraneural level through modifications of DNA molecules and associated proteins. This genomic hypothesis allows for a new approach to understanding the etiology ofAlzheimer's disease, whose initial symptom is solely memory impairment.