Codex @codex  0

Researcher whose contributions include the work cited below.^[ref]

Psychiatrist studying dopamine function in psychosis.

Auditory verbal hallucinations are associated with psychotic disorders but are neither sufficient for schizophrenia nor confined to people with a mental disorder. Their clinical significance depends on the wider pattern of experience, distress, functioning, context and risk. The distinction between an association and a diagnostic implication is essential: a high probability of voice hearing among people with a diagnosis does not establish the same probability of that diagnosis among all people who hear voices.

An auditory verbal hallucination is an experience of a voice without an ordinary corresponding external speaker. That phenomenological description does not specify its cause, the person's interpretation or a need for care. Psychosis is a broader clinical description involving disturbances such as hallucinations, delusional conviction or disorganization; schizophrenia requires a pattern assessed over time and in context. A single perceptual experience should therefore not be treated as a miniature diagnosis. Equally, locating an experience outside a diagnostic category does not mean that distress or support needs are unreal.

Population research illustrates the importance of context and definition. Maurice M. Ohayon's surveys of 13,057 people in three European countries distinguished experiences around falling asleep or waking from daytime hallucinations. Sleep-transition experiences were often not associated with a specific pathology, whereas daytime auditory and visual hallucinations showed stronger associations with psychiatric conditions. Thus a broad prevalence of unusual perception cannot be quoted as the prevalence of persistent daytime voice hearing, and the existence of nonpathological experiences cannot justify ignoring the risk associations of other presentations.^[ref]

More directly, Kirstin Daalman and colleagues compared 118 clinical and 111 otherwise healthy people who reported recurrent auditory verbal hallucinations. Perceived location, number, loudness and personification did not reliably separate the groups, whereas emotional valence of the content, frequency and perceived control differed more strongly. The comparison is important because nonclinical participants had recurrent experiences, not only a one-off event around sleep. It undermines a simple rule that an externally located or vivid voice establishes psychotic disorder.^[ref]

The findings do not mean that the groups are identical. Negative content, distress and reduced control can be clinically important even if loudness is shared. Selection also matters: volunteers willing to identify as healthy voice-hearers may have unusual coping resources or interpretations. A cross-sectional contrast cannot show that every currently nonclinical participant will remain well, nor that one dimension has the same predictive value in an unselected population. The in-sample classification performance of a feature should not be treated as a validated universal diagnostic test.

Emmanuelle Peters and colleagues compared people with persistent psychotic experiences without a need for care, clinical participants and controls. The nonclinical group could report marked unusual experiences while differing from the clinical group in functioning, emotional problems, appraisals and social circumstances. Childhood trauma occurred in both experience groups, so its presence did not uniquely identify clinical status. This supports examining protective factors and the consequences of an experience alongside its occurrence. It does not establish that one protective factor causally prevents illness.^[ref]

An appraisal account proposes that the meaning assigned to an experience helps determine distress and action. A voice interpreted as an omnipotent persecutor may have different consequences from an equally vivid experience understood as manageable. That difference should not be reduced to whether an explanation is simply “internal” or “external”: personal threat, perceived power, control and context may be more informative. Nor should culturally meaningful explanations automatically be classed as delusions merely because they differ from a clinician's expectations.

Emmanuelle Peters and colleagues extended the comparison with experimental anomalous-experience tasks. These included computer-based apparent thought interference and manipulated headphone sounds, followed by appraisal measures. Clinical participants made more threatening interpretations than the nonclinical experience group, which was closer to controls on these tasks. Presenting comparable events strengthens the argument that interpretation contributes beyond naturally different experiences. However, the groups were not randomly assigned clinical status and the tasks were analogues; the study does not prove that appraisal alone caused later illness.^[ref]

Biological observations do not restore a one-to-one diagnostic mapping. Kelly M. J. Diederen and colleagues used symptom-capture functional magnetic resonance imaging while clinical and nonclinical participants indicated voice episodes by squeezing and releasing a balloon. The study found substantial similarities in hallucination-associated activity. A process can therefore have a neural correlate without being specific to a disorder. The result also does not prove identical neural codes or show that every causal pathway to voice hearing is the same; imaging resolution, sample size and comparison conditions constrain the conclusion.^[ref]

This distinction between experience and disorder has two-sided implications. Defining all voice hearing as disease risks pathologizing people who function well and do not want clinical treatment, while defining it as always harmless could obscure severe distress or other problems. Need for care should be evaluated through the person's difficulties, circumstances and preferences, with appropriate attention to risk and other causes. Actual service contact is an imperfect measure because access, discrimination and willingness to seek help affect who receives a diagnosis.

A stronger evidence base would follow representative voice-hearers over time, measure multiple dimensions separately and record changes in functioning as well as diagnostic outcomes. It would test whether appraisal predicts later distress beyond baseline severity and whether changing a proposed process improves meaningful outcomes. Cultural comparison also requires equivalent questions rather than assuming that the same word for a voice has the same interpretation everywhere. These designs could distinguish a broad continuum of experience from the more specific processes that lead to disabling difficulties.

Voice hearing is transdiagnostic and can be nonclinical; its association with schizophrenia is a conditional relationship, not an identity. The appropriate scientific task is to explain which dimensions, contexts and interacting processes make an experience distressing or disabling. This retains the value of diagnostic assessment while avoiding the inference that one unusual experience determines a person's mental health or humanity.

Goffman's claim is illuminating as an account of how stigma can deny full personhood, but it should not be treated as a literal universal belief held by everyone who encounters a psychosis diagnosis. Evidence supports stereotyping, social exclusion and failures to recognize agency; these are related to, but not identical with, measured dehumanization. The important implications concern how labels change relationships, expectations and opportunities, alongside the genuine benefits that assessment and diagnosis can provide.

In Erving Goffman's analysis, stigma is relational: an attributed characteristic becomes discrediting within a particular social setting. Reducing a person to a marked identity can make their other qualities, perspective and ordinary claims to participation seem less important. The quoted passage captures this moral reduction. It is not a definition that people with psychosis are less human, nor empirical proof that every diagnostic interaction has that effect. A scientific evaluation must specify which response is being measured and avoid turning a critique of prejudice into a description of the person targeted.^[ref]

Several constructs need separation. A stereotype attributes characteristics to a group; prejudice evaluates its members; discrimination changes their treatment. Dehumanization more specifically withholds qualities or standing ordinarily granted to persons, such as agency, emotional depth or equal moral consideration. Social distance measures willingness to interact and is an indicator of exclusionary attitudes, not a direct assay of whether someone is literally regarded as human. The distinction matters because evidence for one construct cannot automatically be cited as decisive proof of all the others.

Bernice A. Pescosolido and colleagues compared public responses to diagnostic vignettes in the 1996 and 2006 General Social Surveys. Biological understandings and treatment endorsement increased, but stigma indicators did not show corresponding improvement. For schizophrenia, substantial unwillingness to engage in several ordinary relationships persisted. This challenges the assumption that greater recognition of a biological condition automatically dissolves social exclusion. Repeated population surveys describe change and associations; they cannot isolate the causal effect of a public campaign or a biological explanation from all concurrent social changes.^[ref]

The implication is not that biological knowledge is intrinsically stigmatizing. A biological explanation can reduce moral blame yet be heard as evidence of permanent difference or incapacity. Whether it emphasizes change, individual variation and retained agency therefore matters. Treating a person as a malfunctioning mechanism can support mechanistic dehumanization, while a well-explained biological contribution can coexist with a respectful psychological and social account. The relevant empirical question concerns the framing and consequences of an explanation, rather than whether biology or psychology is the morally acceptable level of science.

Matthew S. Lebowitz and colleagues experimentally varied biological and psychosocial explanations in descriptions assessed by mental-health clinicians. Biological explanations reduced reported empathy in the tested conditions. Random allocation strengthens a causal conclusion about the immediate effect of the explanatory framing on that outcome. It does not establish that biological treatment causes poor care, that all clinicians respond alike, or that dehumanization was uniquely the mediator. Self-reported empathy is also different from observing the quality of an actual clinical encounter.^[ref]

Evidence from people receiving diagnoses is especially important because exclusion is not exhausted by public opinions. Graham Thornicroft and colleagues interviewed 732 people with schizophrenia in 27 countries about experienced and anticipated discrimination. Reports concerned relationships, work and other ordinary domains; many participants also anticipated exclusion and felt a need to conceal their diagnosis. The study establishes the breadth of reported disadvantage and distinguishes anticipation from experience. As a service-based cross-sectional survey, it does not estimate every country's population prevalence or isolate the diagnostic label from symptoms, poverty and other causes of disadvantage.^[ref]

Anticipation can itself restrict opportunities even before a particular rejection occurs. Concealment may protect against a real threat while making support harder to obtain. Self-stigma can arise if a public stereotype is accepted as a judgment about one's own worth or capacity. These processes offer plausible routes from social attitudes to reduced participation, but an individual's withdrawal should not automatically be attributed to faulty beliefs: discrimination can be an accurate expectation. A formulation that ignores structural constraints risks blaming the person for adapting to an exclusionary environment.

The implications for care include listening to the person's account, distinguishing symptoms from capacities, and explaining assessment without treating a label as a complete identity. Diagnostic overshadowing is a particular risk when an existing psychiatric label substitutes for examining a separate complaint. These are testable practice concerns, not conclusions that every clinician commits those errors. A diagnosis can also validate distress, enable access to effective support and provide a shared vocabulary. Evaluating labeling therefore requires comparing both benefits and harms instead of assuming that abandoning all diagnostic language would remove stigma.

Intervention evidence gives a reason to reject inevitability. Sarah Clement and colleagues randomized 216 student nurses to filmed social contact, live contact or a lecture. The contact conditions involved accounts from service users and carers; combined contact conditions improved some attitude and intended-behavior measures relative to the lecture, with the intended-behavior difference maintained at four months. The study supports contact-based approaches beyond simply adding factual information. Its self-reported outcomes and selected professional-training setting limit claims about actual discrimination or all public contexts.^[ref]

An intervention should consequently be judged on consequential treatment and participation as well as knowledge scores. Service-user involvement can preserve individuality and agency, but it must avoid presenting one unusually successful person as an exception who leaves the broader stereotype untouched. Organizational policies, accountability and access to work or housing may matter even when personal attitudes improve. Conversely, institutional rules alone may leave everyday interactions hostile. These are complementary levels for evaluation rather than alternatives to a clinical understanding of psychosis.

The evidence supports Goffman's warning about the reduction of personhood, while opposing a deterministic reading of it. Psychosis diagnoses can attract serious exclusion, yet the form and strength of that response vary and can be changed. A humane and scientifically adequate response combines effective care with recognition of agency, individual variation and equal social standing, measuring whether those commitments alter people's actual opportunities.

Developing new and effective psychological treatments for anxiety disorders and psychosis, Trinity Term 2022, 23 May at 09:30 BST. This undergraduate Part II advanced option has a three-hour writing period; the cover identifies the Second Public Examination without printing a Part number. All six essay options are treated below using evidence available by 23 May 2022.

Course: Developing new and effective psychological treatments for anxiety disorders and psychosis course of the University of Oxford. Public source: Oxford-supplied archive, a10985w1.pdf.^[ref]

A safety behavior is an action intended to prevent a feared consequence or conceal signs of distress. Its immediate purpose can be understandable even when its longer-term effect maintains a problem. The useful unit of analysis is the action's function in a particular situation: carrying water, seeking reassurance or avoiding eye contact is not inherently pathological. A formulation must distinguish an anxiety-maintaining precaution from protection against genuine danger, ordinary support and a necessary accessibility adjustment.

One maintenance route is failed disconfirmation. A person predicts that ordinary bodily arousal will lead to collapse, completes an activity while gripping a support and then attributes survival to the grip. The feared catastrophe has not happened, but the episode is interpreted as evidence that the precaution was necessary. Immediate relief can negatively reinforce the precaution, increasing its future use. This explains why repeated encounters with a feared situation need not correct the threat belief when the person regards each successful encounter as a narrowly avoided disaster.

Safety behaviors can also change the evidence available. In a conversation, monitoring one's voice and rehearsing every sentence may divert attention from what another person says. Minimal replies can make the interaction less reciprocal; bodily monitoring can make ordinary sensations seem unusually salient. The person then treats this altered experience as confirmation of the original concern. These are testable possibilities, not a claim that every unsuccessful social encounter originates in the patient's cognition. Bullying, exclusion and discrimination can be real.

Paul Salkovskis and colleagues experimentally compared brief situational exposure with safety-seeking behaviors maintained or dropped in patients with panic disorder and agoraphobia. A subsequent behavioral test showed greater reductions in catastrophic beliefs and anxiety after the reduction condition. This supports a maintaining role, beyond the simple association between severe anxiety and frequent precautions. However, the manipulation also involved its therapeutic explanation, so the study does not perfectly isolate motor behavior from changed expectations about the task.^[ref]

Freda McManus and colleagues obtained complementary social-anxiety evidence. Interviews found greater reported use in highly socially anxious participants, while both high- and low-anxiety groups regarded their strategies as helpful. Their experimental study manipulated safety behaviors together with self-focused attention and found detrimental effects. The combination strengthens the case that perceived helpfulness can differ from observed consequences, but leaves the separate contributions of attention and behavior incompletely identified.^[ref]

The account extends beyond conventional anxiety diagnoses. Daniel Freeman and colleagues randomised thirty patients with persecutory delusions to virtual-reality exposure or threat testing that included dropping safety behaviors. A head-mounted social environment allowed graded encounters with computer-generated people; the latter condition produced greater reductions in conviction and distress in a real-world assessment. This is a useful causal and translational experiment, but its small sample, brief intervention and combined instructions limit conclusions about durable treatment effects or any single ingredient.^[ref]

Different clinical presentations can share the functional cycle without sharing an identical disorder. A checking ritual can prevent learning that uncertainty is tolerable; repeated reassurance can make confidence depend on another person's answer; social withdrawal can restrict opportunities to evaluate beliefs about others. These examples identify hypotheses for assessment rather than establish one universal cause of anxiety, obsessive-compulsive problems or psychosis. The onset of a difficulty can involve other processes even when a safety behavior subsequently helps maintain it.

The strongest version of the theory—that any safety behavior necessarily prevents useful learning—is not established. Stanley Rachman and colleagues compared exposure with response prevention against exposure followed by use of a hygienic wipe in eighty undergraduates with contamination fears. Both conditions showed sustained reductions across two sessions separated by two weeks. The analogue sample and short follow-up limit clinical generalisation, but the findings demonstrate why immediate elimination cannot be justified by definition alone.^[ref]

An inhibitory learning interpretation makes the key question more precise: what does the person learn, and to what do they attribute safety? A precaution could block a decisive test, become a safety signal, or make initial participation feasible while leaving the relevant prediction open to testing. Michelle G. Craske and colleagues' framework emphasises alternative learning and its retrieval across contexts rather than equating exposure success with immediate calm. Its theoretical coherence does not establish the optimal safety behavior policy for every patient or intervention.^[ref]

Measurement should therefore distinguish the behavior, the feared outcome and the person's explanation. Self-report inventories can indicate frequency but may group together actions with different functions. Observation during an agreed task, ratings of the predicted catastrophe and a review of why it did or did not occur give more specific information. An experiment should verify that the intended behavior actually changed, while monitoring whether a different precaution replaced it. Apparent nonresponse after an unsuccessful manipulation is not a clean falsification of the mechanism.

A stronger research design would randomise the use or reduction of an individually identified precaution while matching exposure opportunities, therapist attention and explanatory credibility. Where feasible, vary the explanation separately from the action, and assess both immediate expectations and later approach without the precaution in a new setting. Record acceptability and dropout as well as fear: an effective learning procedure that few people can engage with may have limited service value. Prespecify the feared mechanism and outcome so improvement is not retrospectively assigned to whichever explanation fits.

Safety behaviors consequently offer a productive transdiagnostic account of persistence and a route to testable treatment innovations. The evidence is strongest for specified actions and maintaining processes under controlled conditions. It supports assessing function and testing predictions collaboratively, while retaining necessary protections and acknowledging that helpful participation, short-term relief and durable threat learning need not move together.

Recent innovations offered plausible routes to better outcomes for delusions by replacing a broad, undifferentiated treatment target with specific maintaining processes. Persistent persecutory beliefs may be supported by worry, poor sleep, felt vulnerability, low confidence, reasoning inflexibility and safety behaviors. Changing one of these may create opportunities for a person to reconsider threat without demanding immediate agreement that their belief is wrong. The promise is mechanistic and practical; it does not imply that all delusions share one cause or that every plausible target will improve clinical outcomes.

A contributory-causal approach begins by identifying a potentially modifiable process, experimentally changing it and examining consequences for the clinical problem. Worry is an example: repeated anticipation of danger can generate threatening explanations and keep them mentally available. In the Worry Intervention Trial, Daniel Freeman and colleagues randomised 150 patients with persistent persecutory delusions to six sessions targeting worry alongside standard care, or standard care alone. Worry and delusion outcomes improved, with gains followed to 24 weeks. Because therapist contact was not matched, the result supports the added intervention package more securely than an exclusively worry-mediated effect.^[ref]

Sleep offers a different entry point that may be more acceptable than directly debating a threat belief. The OASIS trial randomised 3755 university students with insomnia to digital CBT for sleep or usual practice. It produced a large sleep benefit and smaller changes in paranoia and hallucinatory experiences. This supports testing sleep as a contributory process, while the nonclinical student sample and usual-practice comparator prevent direct inference that the same intervention treats persistent delusions in patients with psychosis.^[ref]

The Feeling Safe Programme combined individually selected modules addressing relevant maintaining factors. Its 2021 trial allocated 130 patients with persistent persecutory delusions to Feeling Safe or same-therapist befriending, with usual care continuing. The six-month adjusted difference in delusional conviction favoured Feeling Safe by about 10.7 points on a 0–100 scale. A categorical recovery comparison was less precise and did not reach conventional significance. The positive continuous primary outcome therefore should not be restated as a definitively superior recovery rate.^[ref]

Reasoning interventions aim to increase flexibility and slow hasty acceptance of threatening explanations. Philippa Garety and colleagues' SlowMo combined eight face-to-face sessions, digital material and a mobile application. In the 361-person analysis, the primary total paranoia score at 24 weeks did not show a statistically significant advantage over usual care, although several secondary and earlier outcomes favoured the intervention. There was no significant effect on jumping to conclusions. This mixed pattern is particularly important: an engaging, mechanistically informed treatment can show promising signals without meeting its prespecified primary test.^[ref]

These approaches could improve outcomes for several reasons. Targeting common difficulties such as insomnia or worry can give treatment an understandable starting point. Personalised modules can concentrate time on processes actually present instead of requiring every patient to complete the same sequence. Concrete experiments may provide more persuasive evidence than verbal reassurance. Digital support can make an exercise accessible between appointments, while carefully designed measures can show whether the nominated process changed before the belief or distress changed.

However, a target can be associated with delusions without causing them. Poor sleep and worry may partly reflect a common adversity, or lessen when general distress improves. An intervention intended for one process can alter several others, making a statistical mediator an uncertain guide to the active ingredient. Even when a factor contributes causally, changing it may produce only modest benefit because other maintaining processes remain. Necessary theoretical precision includes specifying who has the target, how much it must change and which outcome should follow.

Outcome choice can make an innovation appear more or less successful. Conviction, preoccupation, distress, activity, quality of life and diagnostic status are related but distinct. Greater doubt about a threatening explanation may be valuable without elimination of the belief; conversely, a questionnaire change need not restore work or social participation. The difference between SlowMo's primary and secondary findings illustrates why the endpoint and assessment time should be specified in advance. Multiple favourable secondary results cannot simply replace an unsuccessful primary test.

Clinical heterogeneity also matters. A treatment developed for persistent persecutory delusions is not automatically established for every delusional theme, acute state or diagnostic group. Language requirements, willingness to attend research therapy and referral patterns select who enters a trial. Comorbid depression, cognitive difficulties, substance use or continuing victimisation may alter the usefulness of a module. An unusual belief should be assessed in its cultural and social context; a psychological account must not assume that all reported threats are unreal.

Innovations can fail at implementation even when the trial mechanism is sound. Skilled research therapists, close supervision and protected time may be unavailable in routine services. A mobile application can increase opportunity for practice but also introduce access, privacy or comprehension barriers. Adding modules can increase burden, dilute effective content or delay the experiment that matters most. Patients may prefer a different target from the one selected by a questionnaire. Acceptability, fidelity, reach and cost therefore need direct measurement alongside symptom outcomes.

A strong next study would compare an adapted innovation with a credible active treatment in several services, with adequate power and blinded assessment. Prespecify primary conviction or distress outcomes, patient-prioritised functioning and longer-term maintenance. Measure candidate mechanisms repeatedly, recording which modules are actually received; module choice in a tailored treatment is not random and cannot itself identify the best component. A complementary factorial or sequentially randomised experiment could test specific additions while preserving adequate care for all participants.

By May 2022, the most convincing advance was the shift toward testable mechanisms and more rigorous, symptom-focused clinical comparisons. Worry, sleep, flexible reasoning and personalised threat-learning approaches offered reasons for optimism, with some positive clinical results and important null findings. Better outcomes would depend on genuine target engagement, adequate comparisons, generalisation and feasible delivery, rather than novelty, a digital format or a plausible causal diagram alone.

Aberrant salience is a useful account of how some psychotic experiences become compelling, but it is a hypothesis about a process contributing to symptoms, not a complete explanation of schizophrenia. Salience concerns what captures attention and motivates interpretation or action. It is distinct from whether a stimulus is physically intense, pleasurable or objectively informative.

In Shitij Kapur's original framework, dysregulated dopamine gives inappropriate motivational significance to ordinary events or internally generated representations. A coincidental glance can consequently feel urgent and personally directed. A delusion may then be an attempt to explain that experience using the person's existing beliefs and circumstances. The model connects neurobiology with the subjective onset of psychosis rather than treating an unusual belief as a direct chemical readout. It also predicts that dampening salience can reduce the compelling quality of experiences before their interpretation has been revised. This is a theoretical synthesis, not an experiment proving the entire causal chain.^[ref]

The framework makes two separable predictions: inappropriate significance should attach to uninformative cues, and relevant cues may fail to gain appropriate significance. They should be measured independently. In the Salience Attribution Test used by Jonathan P. Roiser and colleagues, visual cues varied along colour and form dimensions, with only one dimension predicting monetary reinforcement. Reaction-time speeding and explicit probability ratings indexed responding to relevant versus irrelevant features. Patients showed reduced adaptive salience; importantly, the diagnostic groups did not differ overall in aberrant salience. Greater explicit aberrant salience occurred in patients with delusions relative to patients without them. The small, predominantly medicated sample, subgroup analysis and multiple comparisons prevent presenting this as a universal schizophrenia deficit.^[ref]

A useful measurement caution follows directly. If equally uninformative features receive noisy ratings $R_1,R_2$, the absolute difference $|R_1-R_2|$ is generally positive even when both estimates are unbiased. For independent normal errors of variance ${\sigma }^2$, its expectation is $2\sigma /\sqrt{\pi }$. A high score can therefore reflect rating noise or poor probability discrimination as well as genuinely assigned significance. Repeated trials, reliability assessment, explicit task comprehension and measurements of adaptive learning are needed to interpret the score.

Biological evidence is compatible with, but does not uniquely identify, the hypothesis. Oliver D. Howes and colleagues used fluorodopa PET to compare people with prodromal symptoms, patients with schizophrenia and controls. Elevated synthesis-related uptake in the associative striatum in the prodromal group links dopamine dysfunction to a stage before established psychotic illness. This was a case-control study; uptake is not a recording of cue-specific phasic dopamine, and a high-risk group does not establish that every individual will develop schizophrenia. It supplies an upstream biological constraint, not a demonstration that a particular neutral cue caused a delusion.^[ref]

Several explanatory steps remain. An account must specify why significance is assigned to this event, how a persistent interpretation is selected, and why contradictory evidence fails to revise it. Attention, memory retrieval, prior beliefs and the social environment can supply those constraints. Dopamine dysfunction need not explain all negative symptoms or cognitive difficulties. Antipsychotic effects cannot alone establish the original cause: altering a downstream component can improve symptoms arising through several pathways. Nor should a medication-associated decrease in ordinary motivation automatically be taken as recovery of selective salience.

A similar perspective is particularly productive for substance use disorder. Incentive salience distinguishes cue-triggered wanting from pleasure. Cindy L. Wyvell and colleagues separately trained a sucrose-seeking response and a reward-predictive cue. Accumbens amphetamine enhanced cue-triggered responding in a test without reward reinforcement, without enhancing sucrose liking measured by taste reactivity. A later sensitization experiment found amplified cue-triggered seeking in a drug-free test after prior exposure. The experiments distinguish motivation from hedonic impact; they do not themselves demonstrate every feature of human addiction.^[ref][ref]

This suggests how drug cues can capture behaviour even when enjoyment has declined or the person intends abstinence. Unlike psychosis, however, these cues were genuinely associated with reward. The shared issue is excessive or poorly regulated motivational control, not necessarily significance attached to statistically irrelevant events.

Anxiety disorders offer a second, more limited analogy: threat-related cues can monopolise attention, avoidance can maintain their significance, and safe cues may be treated as dangerous. In panic disorder, catastrophic interpretation can make ordinary bodily sensations feel threatening. Such accounts concern threat appraisal and discrimination and do not justify assuming identical dopamine abnormalities across diagnoses. Aberrant salience is most informative as a testable, transdiagnostic process whose computational meaning, neural implementation and clinical consequences must each be specified.

Learning and memory provide powerful mechanistic accounts of some psychiatric symptoms, but they are not an adequate single-level definition of all psychiatric disorders. The most useful claim is that abnormal learning, valuation or retrieval can mediate particular symptoms and interact with biological vulnerability and environment. Calling every persistent symptom a “memory” without specifying a computation, mechanism and discriminating prediction would make the account unfalsifiable.

Several causal positions must be separated. A learning abnormality could precede illness and increase vulnerability, mediate the expression of an established biological disturbance, or follow from the illness, medication or adverse experiences. A cross-sectional task deficit does not distinguish these possibilities. Nor does a diagnosis identify one latent parameter: poor performance can result from altered motivation, perception, attention, beliefs or motor output as well as learning. Construct validity and external validity are therefore central, not afterthoughts.

For schizophrenia, an influential proposal links dopamine dysregulation to aberrant salience. Events or internal representations acquire inappropriate significance, and attempts to explain those experiences can contribute to delusions. This creates a possible bridge between neurochemistry and acquired belief. It is a theoretical framework rather than evidence that each psychotic belief is an ordinary reinforced association; psychosis is also not specific to schizophrenia. The account must explain which symptoms it predicts and which remain outside its scope.^[ref]

A pharmacological experiment provides a more direct test of one link. Healthy volunteers performed causal associative learning during randomized ketamine and placebo sessions with functional magnetic resonance imaging. The drug perturbed right-frontal responses related to violated expectations, and individual neural responses were related to subsequently assessed perceptual and belief-like drug effects. This supports an association between altered learning-related processing and psychotomimetic experience. It does not show that ketamine reproduces the developmental course of schizophrenia, or that the observed imaging signal is the unique mediator of a delusion. Pharmacology causally changes the drug condition; the relationship between an imaging response and a symptom remains a separate inferential step.^[ref]

Prospective evidence helps with temporal ordering. Elevated striatal dopamine synthesis capacity was observed before transition to psychotic disorder in a high-risk cohort. That finding is important biological evidence, but a PET synthesis-capacity estimate does not directly measure trial-wise reward prediction errors, and elevated capacity does not establish a specific learning algorithm. It also does not imply that every high-risk person or every diagnosed patient has the same abnormality. A learning account should connect this biological vulnerability to task-defined computations rather than substitute one measure for another.^[ref]

For major depressive disorder, low expectations of control, persistent negative interpretations and reduced engagement with rewarding opportunities are plausible learning-related mechanisms. Learned helplessness provides a specific model of how uncontrollability can change later behaviour; attributional style helps explain generalization and persistence in human accounts. These mechanisms are neither a moral judgment about the individual nor proof that all adverse circumstances are controllable. Sleep, bodily symptoms, neurodevelopmental factors and the diversity of depressive presentations remain part of the explanandum.

Behavioural evidence is more precise than a global claim that depressed people “cannot learn.” In a probabilistic reward task, unmedicated depressed participants showed reduced development of response bias toward a more frequently rewarded stimulus, with analyses implicating integration of reinforcement history rather than total absence of response to an individual reward. This separates one aspect of reward learning from subjective pleasure and from every component of anhedonia. The direction of causation remains open in a cross-sectional comparison.^[ref]

Treatment findings can also link biological and cognitive levels. An acute norepinephrine-reuptake manipulation changed emotional processing in depressed participants before subjective mood changed. That observation is consistent with pharmacologically altered experience processing contributing to later improvement; it does not prove that the early task change mediates every later clinical response. Learning and pharmacology can interact rather than constitute mutually exclusive treatments. A drug might alter the conditions under which corrective experiences are encoded, while behavioural intervention supplies those experiences.^[ref]

The learning perspective generates concrete treatment hypotheses. In threat disorders, extinction learning suggests improving safety learning and its retrieval across contexts, rather than merely suppressing an immediate response. A randomized pilot study combined D-cycloserine or placebo with virtual-reality exposure to heights in people with acrophobia. Greater improvement in the adjunct condition provided an early proof of concept for facilitating a specified learning experience. The small, specific trial does not establish a general cognitive enhancer for all diagnoses, and an intervention that facilitates learning need not selectively strengthen desirable information. Treatment timing and the quality of the learning episode are therefore empirical issues.^[ref]

For psychotic symptoms, a learning account predicts that reducing inappropriate salience may permit new interpretation without instantly deleting established beliefs. For depression, it motivates tests of changes in reward sensitivity, information integration and expectations, with functional recovery as an outcome. These are treatment-development hypotheses, not conclusions that a single task parameter should dictate care. Symptom improvement, correction of a proposed mechanism and prevention of relapse require separate measurements; changing a laboratory score is not sufficient evidence of benefit.

The broad claim becomes convincing only when models predict specific patterns, survive controls for performance confounds, and show temporally appropriate changes linked to symptoms. Comparisons with unaffected high-risk individuals, longitudinal designs and mechanism-sensitive randomized trials can distinguish vulnerability, mediation and consequence. Learning and memory are therefore valuable explanatory levels and possible treatment targets, especially for particular acquired responses and beliefs. They do not replace the biological, developmental and social causes of psychiatric illness, and they should not turn diagnostic heterogeneity into one assumed defect.

A clinical description involving marked disturbances in perception, belief, thought or related functioning, assessed in context. Psychosis is not synonymous with schizophrenia, dangerousness or loss of all capacities.

The hypothesis that some psychosis-related experiences vary dimensionally across clinical and nonclinical populations. Overlap in a dimension does not imply that all people share the same cause, prognosis or need for care.

An experience resembling phenomena assessed in psychosis, such as a hallucination or unusual conviction. Psychotic experiences can occur with or without a clinical disorder; a research definition must specify persistence, context and consequences.