Concepts glossary¶

Short definitions for the terms the KB uses across pages. Grouped by topic; cross-linked to the books, people, and thought experiments where the term originates or is contested.

Schema

Each entry: term (original-language form where useful) — origin / proponent(s) · short definition · related KB pages.

A concept earns its own page (concepts/<slug>.md) when its definition accretes more than an entry's worth of nuance, counter-uses, or cross-scale links. Until then, it lives as an entry here.

Phenomenology and qualia¶

Qualia (sing. quale) — C.I. Lewis, Mind and the World Order (1929); central to late-20thC philosophy of mind. The intrinsic, subjective, qualitative properties of conscious experience — what it is like to see red, taste coffee, feel pain. The unit of phenomenal experience that the hard problem says physical description leaves out. Links: Mary's Room, hard problem, Chalmers, Searle.
Phenomenological experience / phenomenology — Edmund Husserl (early 20thC) for the philosophical method; phenomenal in modern philosophy of mind from Block, Chalmers et al. First-person, lived experience as the explanandum of consciousness studies. Phenomenology (the method) studies the structures of experience from the inside; phenomenal (the property) is the experiential character a state has for the subject. Links: Metzinger, Chalmers, the Phenomenology layer of the ontology.
Hard problem of consciousness — David Chalmers, Facing Up to the Problem of Consciousness (1995); The Conscious Mind (1996). Why physical processes give rise to subjective experience at all — distinct from the "easy problems" (explaining specific cognitive functions). Argues no functional / physical story can close the explanatory gap. Links: Chalmers' The Conscious Mind, Mary's Room, Dennett (rejects the framing).
Problem of other minds — Old (at least Descartes, 17thC); modern formulation in Russell, The Problems of Philosophy (1912). The epistemic question: since experience is intrinsically first-person, how do we know anyone besides ourselves is conscious? We only ever observe behavior, never the experience behind it. The everyday version of the puzzle that p-zombies and the Chinese Room sharpen into formal arguments. Links: Philosophical zombies (p-zombies), Chinese Room, qualia.

Self-models and content streams¶

Phenomenal self-model (PSM) — Thomas Metzinger, Being No One (2003); popularized in The Ego Tunnel (2009). A representational structure the brain builds of itself, which the system cannot recognize as a model — its transparency is what makes a self appear to be present. There is no self, only an ongoing self-modeling process. Links: Metzinger's Ego Tunnel, Metzinger.
Multiple-drafts model — Daniel Dennett, Consciousness Explained (1991). Consciousness is not a single stream feeding a central observer — it's parallel, distributed content drafts undergoing continuous revision; "what was conscious" is fixed only retrospectively, by what the system reports. Links: Dennett's Consciousness Explained, Dennett, opposed by Cartesian theatre.
Cartesian theatre — Daniel Dennett, Consciousness Explained (1991) — coined as a target. The (rejected) picture of consciousness as a single inner stage where mental contents are presented to a central observer. Dennett's name for the residual dualism that survives even in materialist accounts. Links: Dennett, multiple-drafts.

Cognitive biases and illusions¶

Cognitive bias — Term: Amos Tversky & Daniel Kahneman, Judgement under Uncertainty: Heuristics and Biases (Science, 1974). A systematic, predictable deviation from normatively correct reasoning, judgement, or memory. Distinguished from random error by being patterned — same deviation across many subjects in the same direction. The umbrella covers heuristics-and-biases (anchoring, framing, availability), social biases (fundamental attribution error, in-group bias), motivated reasoning, memory biases (hindsight, peak-end), attention biases (negativity bias). Links: Phenomena page — Cognitive illusions and biases, Kahneman's Thinking, Fast and Slow, Introspection.
Cognitive bias vs cognitive illusion — Framing: Kahneman, Thinking, Fast and Slow (2011). Often used interchangeably, but with a useful distinction: a cognitive illusion is the experience of a bias under direct demonstration (the visual-illusion analogue — present a Linda problem, watch the wrong answer feel right); a cognitive bias is the underlying systematic tendency, which produces illusions in lab settings and shapes everyday judgement broadly. Bias is the disposition; illusion is the trigger-revealed instance. Links: Cognitive bias, Phenomena page.

Self-awareness and higher-order states¶

Introspection (deep dive) — Late-19thC structuralist psychology (Wundt's Leipzig lab, Titchener); revived cautiously in modern phenomenology and consciousness studies. The act of looking inward at one's own mental states. Was the dominant method of early scientific psychology, abandoned under behaviorism, partially rehabilitated. Crucial caveat: Nisbett & Wilson (1977) — people routinely confabulate explanations of their own choices and emotions. Introspective reports are about something the brain produces, not direct access to underlying processes. → full page. Links: Phenomenological experience, Multiple-drafts model, Free will.
Reflection — Locke, Essay Concerning Human Understanding (1690) — one of the two sources of ideas alongside sensation. Deliberate, language-mediated, comparatively slow thinking about one's own thoughts. The cognitive operation behind metacognition, deliberation, and explicit self-narrative. Distinct from introspection in being active (running an inference about one's own state) rather than observational (reporting it). Links: Introspection, Multiple-drafts model.
Meta-consciousness · higher-order awareness · meta-awareness — Higher-order theories: David Rosenthal, Two Concepts of Consciousness (1986); meta-awareness as an empirical construct: Jonathan Schooler (2000s+). Being aware that one is aware. Higher-order theories (HOT): a mental state is conscious only when there is a higher-order representation of it; a state without a HOT-companion is unconscious even if it influences behavior. Meta-awareness as Schooler uses it: the moment you "catch" yourself mind-wandering — you were already conscious, but not conscious-of-being-conscious until the meta-level kicked in. Links: Phenomenal self-model (PSM), Qualia, Reflection.

Computational and dynamical accounts¶

Predictive coding / Bayesian brain — Helmholtz (1860s) on unconscious inference; modern form: Rao & Ballard (1999), Friston's free-energy principle (2005+). The brain as a hierarchical prediction machine: each level predicts the activity of the level below, and only prediction errors propagate up. Perception, action, and learning fall out as inference under a generative model. Links: Hawkins's On Intelligence, Frith's Making Up the Mind.
Global workspace theory (GWT) — Bernard Baars, A Cognitive Theory of Consciousness (1988); Dehaene's neuronal global workspace (2000s+). Consciousness as the broadcast of selected content to a workspace accessible by many brain modules — the "spotlight" that lets specialised processors share information. Functional account; agnostic on qualia. Links: Pinker, the Computational models layer.
Integrated information theory (IIT, Φ) — Giulio Tononi, Consciousness as Integrated Information (2004), refined through IIT 2.0 / 3.0 / 4.0. A system is conscious to the degree that its causal structure integrates information that cannot be decomposed into independent parts. Φ (phi) measures this integration. Yields strong predictions but Φ is uncomputable for any realistic system. Links: The Computational models layer; contested status flagged in future entries.

Agency and free will¶

Free will — Ancient question; modern empirical locus: Libet (1983); contemporary popular re-statement: Sam Harris, Free Will (2012); Robert Sapolsky, Determined (2023). The capacity of an agent to choose between alternatives in a way that is genuinely up to them. The question takes three layers: phenomenological (does it feel like we choose?), metaphysical (do we actually originate our choices?), and ethical (can we be morally responsible for them?). Brain activity preparing "voluntary" actions begins before conscious decision is reported, which complicates naive folk views without settling the philosophical question. Links: Gazzaniga's Who's in Charge?, Libet readiness-potential experiment, Compatibilism / hard determinism, Nagel's What Does It All Mean?.
Compatibilism · hard determinism · libertarian free will · illusionism — Compatibilism: Hume, Treatise (1739) onward; Hard determinism: Spinoza (1670s) → modern: Sam Harris, Sapolsky; Libertarianism: Kant, modern Robert Kane; Illusionism: a related but distinct position, e.g. Wegner. The four families of position on free will. Compatibilism: free will is real and compatible with determinism, properly understood (agency = your reasoning processes causing your actions). Dominant academic position; Dennett's home. Hard determinism: every event is causally determined, so free will is illusion. Libertarianism: genuine non-determined choice exists (often via dualism or quantum indeterminacy); fringe academically, mainstream as folk intuition. Illusionism: the feeling of will is a construct the brain produces; closely tied to predictive-processing self-modeling (alien hand syndrome, delusions of control). Links: Free will, Dennett, phenomenal self-model (PSM).

Neural substrate: anatomy, ensembles, dynamics¶

The cross-scale chain the neuroanatomy → neurophysiology → neural dynamics layers of the KB rest on. Each entry is a level in that chain.

Cortical parcellation · parcels · Brodmann areas — Korbinian Brodmann, Vergleichende Lokalisationslehre der Großhirnrinde (1909) — 52 cytoarchitectonic areas; modern multi-modal: Glasser et al., Nature (2016) — 180 areas per hemisphere. The division of the cerebral cortex into discrete regions defined by cytoarchitecture (cell layering, density), connectivity, function, or some combination. Provides the standard coordinate system for "where in the brain X happens." Links: Connectome, Neural pathways, Nicholls's From Neuron to Brain.
Neural pathways · tracts · projections — Anatomical neuroscience throughout the 19th–20thC; modern in-vivo mapping: diffusion tensor imaging (DTI, late 1990s). The directed anatomical connections between brain regions, typically via white-matter fibre bundles. Examples: dorsal / ventral visual streams (Mishkin & Ungerleider, 1982), mesolimbic dopamine pathway, the default-mode long-range connections. Connectomics is the project of mapping these exhaustively. Links: Connectome, Cortical parcellation, Seung's Connectome.
Neuronal ensembles · cell assemblies — Donald Hebb, The Organization of Behavior (1949) — "neurons that fire together wire together"; modern empirical: György Buzsáki on hippocampal sequences, Rafael Yuste on cortical ensembles. Groups of neurons that fire together as a coordinated unit to represent a percept, memory, or motor plan. The functional unit between single neurons and brain regions — what carries cognitive content in the brain. Anokhin's cognitome builds on this idea by treating co-firing groups as nodes of a hypernetwork. Links: Cognitome, LeDoux's Synaptic Self, Anokhin.
Activity patterns · neural population dynamics · oscillations · functional connectivity — Diverse — population coding (Georgopoulos, 1980s); oscillatory dynamics (Buzsáki, 2006 Rhythms of the Brain); functional connectivity (resting-state fMRI, Biswal et al. 1995); neural manifolds (Cunningham & Yu, 2014). Pathways and ensembles don't just exist as wiring — they exhibit characteristic activity over time: firing-rate patterns, oscillations (gamma 30–100 Hz, theta 4–8 Hz, etc.), correlated activity between regions, low-dimensional trajectories on neural manifolds. Increasingly, consciousness research is shifting from static structure to these dynamics as the load-bearing variable — the same wiring can support different conscious states depending on the activity regime. Links: Neural pathways, Predictive coding / Bayesian brain, Dayan & Abbott's Theoretical Neuroscience.
Default Mode Network (DMN) — Marcus Raichle et al., A Default Mode of Brain Function (PNAS, 2001). A set of cortical regions — medial prefrontal cortex, posterior cingulate, precuneus, angular gyrus, parts of the temporal lobe — that are more active at rest than during goal-directed tasks. Implicated in self-referential thought, mind-wandering, autobiographical memory, theory of mind. Disrupted in depression, schizophrenia, and Alzheimer's. Reduced DMN activity correlates with ego dissolution under psychedelics (Carhart-Harris's entropic-brain work). One of the most empirically grounded bridges between brain activity and the self layer of the KB. Links: Phenomenal self-model (PSM), Activity patterns, the Phenomena (psychedelics) and Pathology layers.
Neural correlates of consciousness (NCC) — Francis Crick & Christof Koch, Towards a Neurobiological Theory of Consciousness (1990). The minimal neural mechanisms jointly sufficient for any specific conscious percept. Empirical research programme: find what changes in the brain when a stimulus is consciously perceived vs. processed unconsciously (binocular rivalry, masking, attentional blink, sleep, anaesthesia). Important caveat: a correlate is statistically associated; whether it is constituent of consciousness — the actual carrier — is a separate question. IIT is partly an attempt to move from correlate to constituent. Links: IIT (Φ), Global workspace theory, the Experimental methods layer (binocular rivalry, masking studies).

Altered states of consciousness¶

Altered states of consciousness (ASC) (rus. состояния изменённого сознания, ИСС) — Arnold Ludwig, Altered States of Consciousness (Archives of General Psychiatry, 1966); popularized by Charles Tart's edited volume of the same name (1969). The umbrella term for non-ordinary conscious states — those that differ in structure or content from baseline waking awareness: sleep / dreams, lucid dreams, hypnosis, meditation, psychedelic states, dissociation, sensory-deprivation states, near-death experiences, flow. The KB treats these as the most informative probes of ordinary consciousness — what they deform reveals what the default state holds together. Links: Phenomena page — ASC section, DMN, Phenomenal self-model (PSM), Serotonin.

Biochemistry and neuromodulation¶

Activity patterns of pathways and ensembles don't run "neutral" — they are continuously modulated by neurotransmitter systems that change excitability, gain, and timing across whole brain regions. This is the bridge from molecules to network dynamics.

Neuromodulation (vs. fast neurotransmission) — Distinction crystallized in the 1970s–80s; modern review e.g. Marder, Neuromodulation of Neuronal Circuits (2012). Fast neurotransmission (glutamate, GABA): point-to-point, milliseconds, opens ion channels directly — does the circuit's computation. Neuromodulation (dopamine, serotonin, ACh, NE, neuropeptides): slower (seconds to minutes), diffuse, acts via G-protein-coupled receptors that change cellular gain and excitability — sets the circuit's operating mode. Same wiring → very different behaviour under different modulator regimes. Links: Activity patterns, DMN, the Biochemistry and Phenomena layers.
Glutamate · GABA (fast excitatory / inhibitory) — Glutamate as neurotransmitter: Krnjević & Phillis (1963); GABA: Krnjević & Schwartz (1967). The workhorses of cortical computation. Glutamate is the principal excitatory transmitter (~80% of cortical synapses); GABA the principal inhibitory transmitter. Their balance (E/I ratio) sets cortical excitability and shapes oscillations. Disruption is implicated in epilepsy, schizophrenia (NMDA-receptor hypofunction), anxiety, and anaesthesia. Links: Activity patterns, Frith's Schizophrenia VSI, the Pathology layer.
Dopamine (deep dive) — Carlsson, Lindqvist & Magnusson (1957) — dopamine as a neurotransmitter (Nobel 2000); reward-prediction-error formulation: Schultz, Dayan & Montague (1997). Modulator across four anatomically distinct pathways (mesolimbic, mesocortical, nigrostriatal, tuberoinfundibular), each with its own computational role. Phasic mesolimbic firing encodes reward prediction error; mesocortical signals gate working memory; nigrostriatal signals action vigour. No unitary phenomenal correlate — dopamine modulates activity patterns, doesn't constitute felt states. → full page for L-DOPA / wanting-vs-liking / why "increasing dopamine = feeling better" is wrong. Links: Free will, Predictive coding, Activity patterns, Dayan & Abbott's Theoretical Neuroscience, Frith's Schizophrenia VSI.
Serotonin (5-HT) — Rapport, Green & Page (1948) — serotonin isolated; 5-HT2A as the psychedelic receptor: many lines, classic Glennon (1980s). Modulator of mood, sleep, satiety, and — crucially for this KB — perceptual binding and the sense of self. Released from the raphe nuclei. The 5-HT2A receptor is the principal target of classical psychedelics (LSD, psilocybin, DMT, mescaline) — agonism at 5-HT2A drives the perceptual and ego-dissolution effects. SSRI antidepressants raise synaptic 5-HT broadly; the mechanism of clinical effect remains contested. Links: DMN (psychedelic ego dissolution), Shulgin's PiHKAL, Grof's Realms of the Human Unconscious, the Phenomena layer.
Acetylcholine (ACh) — Loewi (1921) — first chemical neurotransmitter identified (Nobel 1936). Modulator of attention, arousal, learning, and REM sleep. Two source systems: basal forebrain (cortical projections — attention, memory, lost in Alzheimer's) and brainstem (thalamic and cortical activation — wakefulness and REM). ACh shifts cortex from internal-processing to external-attention modes. Anticholinergic drugs cause confusion and hallucinations; cholinesterase inhibitors are first-line Alzheimer's treatment. Links: Activity patterns, the Phenomena (sleep, dreams) and Pathology layers.
Norepinephrine (noradrenaline, NE) — Identified as a CNS transmitter in the 1950s; locus-coeruleus targets mapped through the 1960s–70s. Modulator of arousal, vigilance, and the gain on sensory processing. Single source nucleus: the locus coeruleus in the brainstem, projecting almost everywhere in cortex. NE release tracks salience and surprise; LC-NE activity is one of the most direct correlates of arousal level and attentional engagement. Implicated in stress, ADHD, and the cognitive symptoms of depression. Links: Activity patterns, Predictive coding (NE as a precision / gain signal), the Pathology layer.
Adenosine and the caffeine system — Adenosine as neuromodulator: Sattin & Rall (1970); A2A as caffeine target: Daly et al. (1980s). The brief explicitly names this as a KB topic. Adenosine accumulates during waking activity and acts on A1 / A2A receptors to suppress arousal-promoting circuits — it is the molecular basis of sleep pressure. Caffeine is an adenosine-receptor antagonist: it blocks A1 / A2A and disinhibits arousal systems, producing wakefulness without supplying any "energy" itself. Direct molecular handle on the wake / sleep / consciousness axis. Links: Activity patterns, the Phenomena (sleep) and Energetics layers.

Cargo-cult neurochemistry — folk phrases that pose as science

A family of widespread phrases dresses folk intuitions in neurotransmitter vocabulary. The vocabulary makes them sound scientific; the underlying claims are often wrong or untestable as neuroscience — and using the wrong vocabulary actively blocks proper questioning. Saying "I need more dopamine" is doing the same job as saying "I'm out of qi" — gesturing at a real felt-state with a borrowed vocabulary that doesn't map to the mechanism. By posing as scientific while bypassing scientific reasoning, these phrases are anti-scientific in effect.

Common offenders:

"Cheap dopamine" — that social media, sugar, and short-video feeds give cheap hits to be earned back via "dopamine fasting." Dopamine is not the pleasure chemical — it encodes reward prediction error (Schultz, Dayan & Montague, 1997) and incentive salience (Berridge & Robinson). Hedonic liking lives in opioid hotspots in the nucleus accumbens shell, not in dopamine per se. There is no cheap vs expensive dopamine at the molecular level.
"Dopamine fasting" (Cameron Sepah, 2019) — you can't deplete or rest dopamine by avoiding stimuli; it isn't a battery. Sepah himself has said the popular reading isn't what he meant.
"My body needs more dopamine" / "I don't have dopamine" / "I have low dopamine" — you cannot introspectively sense your own dopamine levels. Dopamine isn't a unitary "amount" sloshing around the brain — it's a phasic signaling system across at least four anatomically distinct pathways (mesolimbic, mesocortical, nigrostriatal, tuberoinfundibular), each doing different things. "Low dopamine" as a self-diagnosis isn't a neurochemical claim; it's a felt-state given a neurochemical-sounding label.
"I need a serotonin boost" — the once-popular monoamine hypothesis of depression (low serotonin → depression) has been substantially weakened by the empirical literature (Moncrieff et al., 2022 umbrella review of serotonin and depression; the SSRI mechanism is now thought to involve neuroplasticity over weeks, not acute serotonin elevation). Saying "low serotonin" with confidence overstates settled science.

What the family is gesturing at, correctly:

High-frequency reward stimuli (notifications, short-video feeds, hyperpalatable food, slot-machine UX) do dysregulate reward circuits — phasic dopamine spikes, downregulated D2 receptors, blunted tonic signaling. The addiction-circuit literature is real.
The accurate framing is wanting vs liking (Berridge): these stimuli drive wanting (motivational pull) without proportional liking (hedonic pleasure). That's the actual problem.
Mood, motivation, and arousal do depend on neuromodulator dynamics — the felt-state is real. What's wrong is treating self-report of the felt-state as a direct readout of any specific neurotransmitter level.

In the KB: use wanting / liking dissociation, reward-circuit dysregulation, and neuromodulator dynamics as the working vocabulary; treat cheap dopamine, low serotonin, and dopamine fasting as folk phrases that need translation before they can carry any scientific weight.

Substrate and emergence¶

Biological naturalism — John Searle, The Rediscovery of the Mind (1992); Mind (2004). Consciousness is real, irreducibly first-person, and caused by specific biological processes in the brain — not by computation, not separable from its substrate. Rejects both dualism and strong AI. Links: Searle's Mind, Chinese Room, Searle.
Connectome — Olaf Sporns, Patric Hagmann, Seung et al. (mid-2000s). The complete map of synaptic / neural connections in a nervous system. You are your connectome (Seung): identity and self emerge from the wiring diagram. Links: Seung's Connectome, LeDoux's Synaptic Self.
Cognitome / гиперсетевая теория мозга — Konstantin Anokhin (2010s+). A level above the connectome: the network of functional hypernetworks — co-firing groups of neurons whose joint dynamics carry cognitive content. Argues cognition emerges at this functional level, not at the wiring level. Links: Anokhin.