Background & Objective: The convergence of human cognition and artificial intelligence (AI) is reshaping cognitive identity and challenging traditional understandings of consciousness, agency, and selfhood. This narrative review introduces a conceptual three-stage model of cognitive hybridization, comprising Simulation, Integration, and Co-Evolution, to examine the dynamics of human-AI interaction and its neuroethical implications.
Materials & Methods: Interdisciplinary evidence from cognitive neuroscience, AI research, and neuroethics was synthesized by drawing on studies published between 2000 and 2025 in PubMed, Scopus, and Web of Science. The review focused on brain-computer interfaces (BCIs), mechanisms of neural plasticity, and the cognitive capacities of large language models (LLMs).
Results: In the Simulation stage, LLMs replicate selected cognitive operations such as language processing, although they lack any biological substrates, including hippocampal encoding and network-level neural dynamics. The Integration stage involves reciprocal interactions between the brain and AI, where BCIs facilitate emergent forms of shared agency mediated through cortical and basal ganglia pathways. The Co-Evolution stage reflects bidirectional adaptive processes that gradually reshape cognitive functions across both developing and aging brains. Key neuroethical considerations include autonomy, cognitive justice, and the protection of neural data and cognitive privacy.
Conclusion: This model highlights the urgent need for updated theoretical and ethical frameworks that can guide human-AI co-evolution and promote equitable and safe cognitive enhancement. The proposed framework offers a structured foundation for future interdisciplinary inquiry in neuroethics and cognitive augmentation.
J. J. Joshua Davis, J. J. Joshua Davis, Florian Schübeler
et al.
This study explores the layered coherence within human cognition as measured through EEG. Signals were collected from two groups (meditators vs. non-meditators) across six conditions: Meditation, Scrambled Words, Ambiguous Images, Math Mind, Sentences, and Video Watching. We analyzed the EEG data using Shannon Entropy, Pearson’s Skewness, Total Power, and Dominant Frequency indices, now taken together, to reveal distinct neurophysiological signatures and a different outcome of hypothesis testing based on one index at a time only. These patterns suggest that cognition is more than merely computational, since it seems to be expressive of deeper experiential states, raising profound questions about the nature of intelligence and whether the human psyche and its experience of meaning, in its different forms, can be meaningfully approached through objective methodologies. Our findings invite a re-examination of scientific inquiry itself, both as a pursuit of mechanistic regularities, and also, holistically, as a means of honoring the subtle interplay between structure and meaning. This is reminiscent of young Carl Friedrich Gauss revealing hidden structure beneath apparent complexity by summing up an arithmetic series with elegant simplicity. This way he reframed a problem through insight rather than brute calculation. If artificial intelligence is to mimic cognition, it must grapple with informational entropy and also with the values and consciousness that give rise to meaning. The entropic balance of EEG signals may offer a window into coherence, yet only a species that is mature enough to honor life, liberty, and the pursuit of deep meaning, should attempt to design artificial “minds.” In this convergence of neuroscience and philosophical reflection, we glimpse a deeper imperative: to preserve the truth of what it means to be human in an age increasingly defined by machines.
Praveen Suthaharan, Santiago Castiello, Yuen-Siang Ang
et al.
Processing uncertainty may be pathognomonic (characteristic of a disease) for some psychiatric conditions. Some people expect the world to change, even when it doesn’t. This tendency is central to paranoia, where individuals often anticipate threat or change without clear evidence. But what determines whether these beliefs translate into behavior? One possibility is that metacognitive structure – the coherence and depth with which one articulates their own thinking – acts as a buffer. An agent may endorse a belief but have sufficient accessory hypotheses to insulate it from action. To test this, we used metacognitive prompting in GPT-4 to score individual reflections on open-ended questions (e.g., did you use any particular strategy?) after completing a probabilistic reversal learning task. Individuals with higher paranoia demonstrate lower metacognitive structure (t = 5.98, p < 0.001), with metacognition attenuating the relationship between volatility belief and switching behavior (Δ = –15 pp, p < 0.001) even after controlling for reflection verbosity and general cognitive ability. These findings suggest that metacognition protects against uncertainty-driven instability, pointing to a key mechanism by which reflection protects against cognition under change. This work provides a novel framework to measure metacognition from behavioral task debrief questions.
Computer applications to medicine. Medical informatics, Psychiatry
Emma Krane Mathisen, Nicholas Allott, Camilo R. Ronderos
This study investigates whether metaphors and similes are processed the same way or not. Comparison accounts of metaphor claim that metaphors and similes use the same cognitive mechanisms because metaphors are implicit similes, while Categorization accounts claim that the two figures of speech require different cognitive mechanisms. It is unclear which position has the most support. We address this by introducing the distinction between single and extended metaphors to this debate. Several experiments have shown that a metaphor preceded by another metaphor is read faster than a single metaphor. If similes in extended and non-extended contexts display a similar processing difference, this would support views saying that metaphors and similes are processed the same way. If not, it would be more in line with the view that they are processed differently. Using an eye-tracking reading paradigm, we find that the difference between processing single and extended metaphors does not hold in the case of simile comprehension. This is more compatible with Categorization accounts than with Comparison accounts; if the cognitive mechanism behind metaphor and simile processing is the same, we would expect there to be a comparable processing difference between metaphors and similes in the single and extended conditions.
In adult readers, the perceptual span is approximately 14–15 characters to the right of the fixated word, corresponding to approximately 5° of visual angle. However, the extent of information processing within this area remains unclear. In the present study, we address this question using a novel adaptation of the flankers task in which the eccentricity of the flankers with respect to the central target word is increased. Fifty-four participants performed a lexical decision task on a central four-letter word flanked by two words of equal length. The flankers were either orthographically related (rock – rock) or unrelated (path – rock) to the target, and their eccentricity varied from 1.65° to 4.29° (center-to-center) in 0.33° steps. Participants’ fixation was controlled by an eye-tracker using the fixation point as a trigger, and stimuli were displayed for 170 ms to avoid any eye movement. Results showed that the effect of unrelated flankers decreased with increasing eccentricity, while there was no effect of eccentricity of related flankers. In particular, the unrelated flankers affected central word processing up to the end of the parafovea. This observation provides evidence that the outer limits of the parafovea are engaged beyond prelexical processing. Lexical frequency influenced the magnitude of both reaction times (RTs) and accuracy rates, but did not interact with any variables. This novel adaptation of the flankers task has potential advantages for investigating the spatial integration of orthographic information across the perceptual span.
Consciousness shared Humans have tended to believe that we are the only species to possess certain traits, behaviors, or abilities, especially with regard to cognition. Occasionally, we extend such traits to primates or other mammals—species with which we share fundamental brain similarities. Over time, more and more of these supposed pillars of human exceptionalism have fallen. Nieder et al. now argue that the relationship between consciousness and a standard cerebral cortex is another fallen pillar (see the Perspective by Herculano-Houzel). Specifically, carrion crows show a neuronal response in the palliative end brain during the performance of a task that correlates with their perception of a stimulus. Such activity might be a broad marker for consciousness. Science, this issue p. 1626; see also p. 1567 A marker for consciousness is identified in a crow’s brain. Subjective experiences that can be consciously accessed and reported are associated with the cerebral cortex. Whether sensory consciousness can also arise from differently organized brains that lack a layered cerebral cortex, such as the bird brain, remains unknown. We show that single-neuron responses in the pallial endbrain of crows performing a visual detection task correlate with the birds’ perception about stimulus presence or absence and argue that this is an empirical marker of avian consciousness. Neuronal activity follows a temporal two-stage process in which the first activity component mainly reflects physical stimulus intensity, whereas the later component predicts the crows’ perceptual reports. These results suggest that the neural foundations that allow sensory consciousness arose either before the emergence of mammals or independently in at least the avian lineage and do not necessarily require a cerebral cortex.
The ability to perceive and recognise a reflected mirror image as self (mirror self-recognition, MSR) is considered a hallmark of cognition across species. Although MSR has been reported in mammals and birds, it is not known to occur in any other major taxon. Potentially limiting our ability to test for MSR in other taxa is that the established assay, the mark test, requires that animals display contingency testing and self-directed behaviour. These behaviours may be difficult for humans to interpret in taxonomically divergent animals, especially those that lack the dexterity (or limbs) required to touch a mark. Here, we show that a fish, the cleaner wrasse Labroides dimidiatus, shows behaviour that may reasonably be interpreted as passing through all phases of the mark test: (i) social reactions towards the reflection, (ii) repeated idiosyncratic behaviours towards the mirror, and (iii) frequent observation of their reflection. When subsequently provided with a coloured tag in a modified mark test, fish attempt to remove the mark by scraping their body in the presence of a mirror but show no response towards transparent marks or to coloured marks in the absence of a mirror. This remarkable finding presents a challenge to our interpretation of the mark test—do we accept that these behavioural responses, which are taken as evidence of self-recognition in other species during the mark test, lead to the conclusion that fish are self-aware? Or do we rather decide that these behavioural patterns have a basis in a cognitive process other than self-recognition and that fish do not pass the mark test? If the former, what does this mean for our understanding of animal intelligence? If the latter, what does this mean for our application and interpretation of the mark test as a metric for animal cognitive abilities? Editor’s note This Short Report received both positive and negative reviews by experts. The Academic Editor has written an accompanying Primer that we are publishing alongside this article (https://doi.org/10.1371/journal.pbio.3000112). The linked Primer presents a complementary expert perspective; it discusses how the current study should be interpreted in the context of evidence for and against self-awareness in a wide range of animals.
We discuss the two moments of human cognition, namely, apprehension (A), whereby a coherent perception emerges from the recruitment of neuronal groups, and judgment(B),that entails the comparison of two apprehensions acquired at different times, coded in a suitable language and retrieved by memory. (B) entails self-consciousness, in so far as the agent who expresses the judgment must be aware that the two apprehensions are submitted to his/her own scrutiny and that it is his/her task to extract a mutual relation. Since (B) lasts around 3 seconds, the semantic value of the pieces under comparison must be decided within that time. This implies a fast search of the memory contents. As a fact, exploring human subjects with sequences of simple words, we find evidence of a limited time window , corresponding to the memory retrieval of a linguistic item in order to match it with the next one in a text flow (be it literary, or musical,or figurative). While apprehension is globally explained as a Bayes inference, judgment tresults from an inverse Bayes inference. As a consequence, two hermeneutics emerge (called respectively circle and coil). The first one acts in a pre-assigned space of features. The second one provides the discovery of novel features, thus unveiling previously unknown aspects and hence representing the road to reality.
Significance This paper provides evidence that a theoretical computer science (TCS) perspective can add to our understanding of consciousness by providing a simple framework for employing tools from computational complexity theory and machine learning. Just as the Turing machine is a simple model to define and explore computation, the Conscious Turing Machine (CTM) is a simple model to define and explore consciousness (and related concepts). The CTM is not a model of the brain or cognition, nor is it intended to be, but a simple substrate-independent computational model of (the admittedly complex concept of) consciousness. This paper is intended to introduce this approach, show its possibilities, and stimulate research in consciousness from a TCS perspective.
Ngoda Manongi MD, MS, Jana Clough DO, Ryan Mirchin DO
et al.
Locked-in syndrome (LIS) is an uncommon neurologic disorder that manifests in quadriplegia and anarthria with preserved cognition and self-awareness. Generally, patients with LIS may live for years with preserved quality of life and cognitive function, but with severe disability. There are 3 types of LIS: classic, partial, and total. The classical form is defined by total immobility, with preservation of the ability to perform vertical eye movements, blink, and maintain a normal level of consciousness. We present an unusual case of classical LIS in a 54-year-old man who presented initially with acute-onset left lower extremity weakness and dysarthria with radiographic evidence of extensive, acute right paramedian pontine infarction and high-grade vertebral artery stenosis. However, a week later, the patient developed sudden-onset aphonia, bilateral facial palsy, and quadriplegia with repeat magnetic resonance imaging of the brain showing expansion of right paramedian pontine stroke to also involve the left paramedian pons, without significant change to the vertebral stenosis and basilar artery patency.
The article presents the course-of-experience framework and how it contributes to studying cognition in practice. The aim is twofold: (a) to argue for a phenomenologically and semiotically inspired enactivist approach to practice and cognition in practice and (b) to describe research methods that provide rigorous first-person data in relation to practice—in other words, a view “from within” of practice. Practice is considered to be a relevant unit of analysis for studying cognition-in-the-world and is defined as enacted, lived, situated, embodied, and enculturated. Practice is not viewed as a “context for” but as “constitutive” of the cognitive process itself. This article describes (a) the epistemological foundation and general assumptions of the course-of-experience framework, (b) the associated way of looking at pre-reflective self-consciousness and its relation to practice, (c) the analytical hypothesis derived from Peirce’s semeiotic, and (d) some methodological considerations related to data collection, data processing, and analysis. In the concluding section, we outline the added value of the course-of-experience framework for cognitive science, and we indicate possible directions for further research.
There is a popular interest in microdosing with psychedelics such as LSD. This practice of using one-tenth of a full psychedelic dose according to a specific dosing schedule, anecdotally enhances mood and performance. Nonetheless, controlled research on the efficacy of microdosing is scarce. The main objective of the present dose-finding study was to determine the minimal dose of LSD needed to affect mood and cognition. A placebo-controlled within-subject study including 24 healthy participants, was conducted to assess the acute effects of three LSD doses (5, 10, and 20 mcg) on measures of cognition, mood, and subjective experience, up until 6 h after administration. Cognition and subjective experience were assessed using the Psychomotor Vigilance Task, Digit Symbol Substitution Test, Cognitive Control Task, Profile of Mood States, and 5-Dimensional Altered States of Consciousness rating scale. LSD showed positive effects in the majority of observations by increasing positive mood (20 mcg), friendliness (5, 20 mcg), arousal (5 mcg), and decreasing attentional lapses (5, 20 mcg). Negative effects manifested as an increase in confusion (20 mcg) and anxiety (5, 20 mcg). Psychedelic-induced changes in waking consciousness were also present (10, 20 mcg). Overall, the present study demonstrated selective, beneficial effects of low doses of LSD on mood and cognition in the majority of observations. The minimal LSD dose at which subjective and performance effects are notable is 5 mcg and the most apparent effects were visible after 20 mcg.
M. Graziano, Arvid Guterstam, Branden J. Bio
et al.
ABSTRACT Here we examine how people’s understanding of consciousness may have been shaped by an implicit theory of mind. This social cognition approach may help to make sense of an apparent divide between the physically incoherent consciousness we think we have and the complex, rich, but mechanistic consciousness we may actually have. We suggest this approach helps reconcile some of the current cognitive neuroscience theories of consciousness. We argue that a single, coherent explanation of consciousness is available and has been for some time, encompassing the views of many researchers, but is not yet recognized. It is obscured partly by terminological differences, and partly because researchers view isolated pieces of it as rival theories. It may be time to recognize that a deeper, coherent pool of ideas, a kind of standard model, is available to explain multiple layers of consciousness and how they relate to specific networks within the brain.
Abstract The association between neural oscillations and functional integration is widely recognized in the study of human cognition. Large-scale synchronization of neural activity has also been proposed as the neural basis of consciousness. Intriguingly, a growing number of studies in social cognitive neuroscience reveal that phase synchronization similarly appears across brains during meaningful social interaction. Moreover, this inter-brain synchronization has been associated with subjective reports of social connectedness, engagement, and cooperativeness, as well as experiences of social cohesion and ‘self-other merging’. These findings challenge the standard view of human consciousness as essentially first-person singular and private. We therefore revisit the recent controversy over the possibility of extended consciousness and argue that evidence of inter-brain synchronization in the fastest frequency bands overcomes the hitherto most convincing sceptical position. If this proposal is on the right track, our understanding of human consciousness would be profoundly transformed, and we propose a method to test this proposal experimentally.