Peripartum Depression and Psychosis - Nosology, Phenomenology, and Research

 Peripartum Depression and Psychosis – A Major Change Is Ignored

 

In my previous post, I covered some of the legal, social, and cultural shortcomings affecting peripartum and postpartum depression and psychosis.  In this post I am going to cover a very basic concept that I have discussed before and that is consciousness. It is a major shortcoming of criteria-based diagnoses like the DSM.  It is conspicuous by its absence. The DSM makes it seem like all you need is a set of criteria, an adequate time frame, and the ability to rule out other causes and you can make any psychiatric diagnosis.  The only time human consciousness enters the picture is when the discussion is of altered states of consciousness like delirium or dementia.  Even then older neurological terms like stupor and coma seem to do a better job of capturing what is happening (1).

The additional limitation of criteria-based diagnoses is that they do not get to a more complete description of behavior. A delusion is not the total experience – the individual’s subjective experience is of secondary importance.  It is assumed that behavior is either predicated on the delusion or other aspects of the person’s life or personality. In psychiatric practice there is an entire other constellation of factors that are typically included in a formulation, but even then, the current subjective experience is not a focus. 

We all have a baseline conscious state that we are familiar with. Most discussions of consciousness begin with a disclaimer about no universally accepted definitions.  A good general definition addresses 2 components – level of consciousness (wakefulness/arousal) and contents of consciousness (specific objects and events that one is aware of).  The content can be encyclopedic but there are also ongoing neurobiological processes to consolidate, cue, and reinforce that content in varying ways. It is a dynamic rather than static process. It has to be in order to give you an integrated experience of life.  The most important product is the integrated first-person experience of oneself and the world.  But it is important to note that consciousness is more than just that since there are additional processes (access, intentionality, self-awareness).

Let me back up a bit and start out with the concept of phenomenal experience. This is the subjective or “what it is like” to have an experience.  A common example in the literature is the color red as in: “My experience of the color red is not your experience.”  That happens at a number of levels but most people consider there is a consensus about the color and leave it at that. Core features include qualia or the pure sensory experience without associated information processing, first-person experience, and distinct from other capacities like reasoning or controlling one’s behavior.

Phenomenal experience is one aspect of human consciousness.  Additional aspects include:

Cognitive access: content can be reported upon, accessed, and manipulated (reasoned about and used to guide action).

Self-awareness:  awareness as oneself with a capacity for generating thought and action.  Ability to distinguish oneself from the world including other people.

Intentionality: directed perception of objects and processes in the environment.

Reflective capacity:  knowing that the sensory experience is more than just sensation e.g. knowing that you see is more than just seeing it leads to an integrated experience at several levels.

Flexible cognitive control:  flexible modulation of attention, processing novel situations, decision-making, and integrating information. That includes daydreaming, fantasizing, mental work, and directing yourself to and away from those processes

There are numerous studies that map these functions onto neuroanatomical structures and neurophysiological events. There is also the interesting mapping of these functions onto ego functions that have been extensively elaborated on since Freud.  An example of a common ego-function that most people have heard of is reality testing.  It is defined just as it sounds: “The components are (a) the distinction between inner and outer stimuli; (b) accuracy of perception (including orientation to time and place and interpretation of external events), and (c) accuracy of inner reality testing (psychological mindedness and awareness of inner states).”  (From Bellak and Goldstein).  I have consolidated these mappings into the following table to illustrate what happens in psychosis.

Feature of human consciousness	Corresponding ego function(s)	How it is altered in psychosis (with examples)	References
Cognitive access / reportability (content broadcast for report, reasoning, action — access consciousness)	Thought processes; judgment; regulation/control	Elevated threshold for conscious access with intact subliminal processing, attributed to disrupted top-down attentional amplification; correlates with reduced long-distance white-matter connectivity in the global-workspace network. Example: schizophrenia patients require longer stimulus durations to consciously perceive a masked word, while unconscious priming is preserved.	[1-3]
Self-awareness and a unified self (awareness of oneself as a persisting agent)	Synthetic/integrative function; relation to reality (self/world demarcation)	Self-disorders with permeable ego-boundaries and disturbed agency; altered cortical-midline (mPFC, PCC/precuneus) and temporoparietal-junction activity during self-reflection and source monitoring. Examples: thought insertion, thought broadcasting, passivity/made experiences, misattributing self-generated actions to others.	[4-6]
Intentionality (aboutness) + distinguishing internal from external	Reality testing (relation to reality)	Breakdown in differentiating internally generated from externally sourced experience across "reality distortion," "uncertainty of perception," and "hallucinations/delusions" domains; reduced parahippocampal/inferior-parietal activity during reality evaluation. Examples: hallucinating a voice with no external stimulus; fixed delusional beliefs; confident memory errors misattributed to real events.	[8-10]
Reflective / metacognitive (higher-order) capacities (knowing that one experiences)	Judgment; synthetic function; observing-ego capacity	Metacognitive deficit with impaired insight and overconfidence in errors; disrupted anticorrelated balance between frontoparietal control and default-mode networks scaling with symptom severity. Examples: poor illness insight (anosognosia for psychosis), high confidence in incorrect judgments, impaired self-monitoring.	[10-12]
Flexible cognitive control (attention modulation, novel contexts, decision-making, cross-modal integration)	Regulation and control of drives; autonomous functions; synthetic function	Imprecise hierarchical predictive coding — low precision of priors relative to sensory data — yielding aberrant salience and maladaptive belief updating via hippocampal-prefrontal-striatal/corticostriatothalamic dysfunction. Examples: aberrant salience attributed to irrelevant stimuli seeding delusions; disorganized thought; failure to integrate prior task outputs into a working schema.	[1, 13-15]
1.  Patniyot NS. Deficits in access consciousness, integrative function, and consequent autonoetic thinking in schizophrenia. Med Hypotheses. 2021 Oct;155:110664. doi: 10.1016/j.mehy.2021.110664. Epub 2021 Aug 13. PMID: 34425452. 2.  Berkovitch L, Charles L, Del Cul A, Hamdani N, Delavest M, Sarrazin S, Mangin JF, Guevara P, Ji E, d'Albis MA, Gaillard R, Bellivier F, Poupon C, Leboyer M, Tamouza R, Dehaene S, Houenou J. Disruption of Conscious Access in Psychosis Is Associated with Altered Structural Brain Connectivity. J Neurosci. 2021 Jan 20;41(3):513-523. doi: 10.1523/JNEUROSCI.0945-20.2020. Epub 2020 Nov 23. PMID: 33229501; PMCID: PMC7821858.. 3.  Berkovitch L, Dehaene S, Gaillard R. Disruption of Conscious Access in Schizophrenia. Trends Cogn Sci. 2017 Nov;21(11):878-892. doi: 10.1016/j.tics.2017.08.006. Epub 2017 Sep 26. PMID: 28967533.6. 4.  Potvin S, Gamache L, Lungu O. A Functional Neuroimaging Meta-Analysis of Self-Related Processing in Schizophrenia. Front Neurol. 2019 Sep 11;10:990. doi: 10.3389/fneur.2019.00990. PMID: 31572296; PMCID: PMC6749044. 5.  Jimenez AM, Green MF. Disturbance at the self-other boundary in schizophrenia: Linking phenomenology to clinical neuroscience. Schizophr Res. 2024 Oct;272:51-60. doi: 10.1016/j.schres.2024.07.048. Epub 2024 Aug 26. PMID: 39190982. 6.  Henriksen MG, Raballo A, Nordgaard J. Self-disorders and psychopathology: a systematic review. Lancet Psychiatry. 2021 Nov;8(11):1001-1012. doi: 10.1016/S2215-0366(21)00097-3. PMID: 34688345.    7. Feyaerts J, Sass L. Self-Disorder in Schizophrenia: A Revised View (1. Comprehensive Review-Dualities of Self- and World-Experience). Schizophr Bull. 2024 Mar 7;50(2):460-471. doi: 10.1093/schbul/sbad169. PMID: 38069912; PMCID: PMC10919772.    8.  Helyel ES, El-Sayed MM. Beyond the symptoms: Exploring attachment styles and reality-testing among schizophrenia clients from a nursing perspective. J Psychiatr Ment Health Nurs. 2025 Feb;32(1):1-12. doi: 10.1111/jpm.13081. Epub 2024 Jul 3. PMID: 38958525.    9.  Lee JS, Chun JW, Lee SH, Kim E, Lee SK, Kim JJ. Altered neural basis of the reality processing and its relation to cognitive insight in schizophrenia. PLoS One. 2015 Mar 20;10(3):e0120478. doi: 10.1371/journal.pone.0120478. PMID: 25793291; PMCID: PMC4368728.  10.  Seabury RD, Bearden CE, Ventura J, Subotnik KL, Nuechterlein KH, Cannon TD. Confident memory errors and disrupted reality testing in early psychosis. Schizophr Res. 2021 Dec;238:170-177. doi: 10.1016/j.schres.2021.10.007. Epub 2021 Oct 25. PMID: 34710715.  11.  Jia W, Zhu H, Ni Y, Su J, Xu R, Jia H, Wan X. Disruptions of frontoparietal control network and default mode network linking the metacognitive deficits with clinical symptoms in schizophrenia. Hum Brain Mapp. 2020 Apr 15;41(6):1445-1458. doi: 10.1002/hbm.24887. Epub 2019 Dec 2. PMID: 31789478; PMCID: PMC7267896.  12.  David AS, Bedford N, Wiffen B, Gilleen J. Failures of metacognition and lack of insight in neuropsychiatric disorders. Philos Trans R Soc Lond B Biol Sci. 2012 May 19;367(1594):1379-90. doi: 10.1098/rstb.2012.0002. PMID: 22492754; PMCID: PMC3318769.  13.  Heinz A, Murray GK, Schlagenhauf F, Sterzer P, Grace AA, Waltz JA. Towards a Unifying Cognitive, Neurophysiological, and Computational Neuroscience Account of Schizophrenia. Schizophr Bull. 2019 Sep 11;45(5):1092-1100. doi: 10.1093/schbul/sby154. PMID: 30388260; PMCID: PMC6737474.  14.  Sterzer P, Adams RA, Fletcher P, Frith C, Lawrie SM, Muckli L, Petrovic P, Uhlhaas P, Voss M, Corlett PR. The Predictive Coding Account of Psychosis. Biol Psychiatry. 2018 Nov 1;84(9):634-643. doi: 10.1016/j.biopsych.2018.05.015. Epub 2018 May 25. PMID: 30007575; PMCID: PMC6169400.  15.  Liddle PF, Sami MB. The Mechanisms of Persisting Disability in Schizophrenia: Imprecise Predictive Coding via Corticostriatothalamic-Cortical Loop Dysfunction. Biol Psychiatry. 2025 Jan 15;97(2):109-116. doi: 10.1016/j.biopsych.2024.08.007. Epub 2024 Aug 22. PMID: 39181388.

 

The table is an indication of what is not in the DSM but what has been described by psychiatrists who were focused on phenomenology in the mid-20^th century. Kurt Schneider suggested that a group of what he called first rank symptoms were a more definite sign of schizophrenia and represented a “radical qualitative change in the thought-processes themselves” rather than a quantitative change.  Norgaard and Parnas expanded on this as “Kurt Schneider explicitly emphasized that the formative matrix out of which the “first rank symptoms” emerge, was a “radical qualitative change” in the field of consciousness, comprising a disturbed first personal perspective(“Ichheit”) and a disturbed sense of “mineness”of experience (“Meinhaftigkeit”).  Schneider argues that the psychosis in schizophrenia is not merely eccentric beliefs or quantitative changes in symptoms but that it is a qualitative change in state.”  In the case of schizophrenia insight and judgment are affected by changes in experience related to these changes in consciousness while baseline sensorium and personality are preserved. 

DSM criteria do not tell you that the person affected by psychosis is operating from an entirely different conscious state. These observations about how a conscious state affect consciousness have been made for centuries. The changes in processing, reality testing, and phenomenal experience also affect moral and ethical decision making.  Baseline moral frameworks are often maintained but the decisions are affected by the changes in experiential reality.  This has been studied in postpartum psychosis and filicide.  Several types of patterns of thought have been noted in studies of filicide and psychosis.  Before I reference those studies, I want to add the following diagram.  It illustrates differences in usage of the term phenomenology in clinical psychiatry.

 

 

The diagram (click to enlarge) shows that some research defines phenomenology as descriptive psychopathology – basically defined sign and symptoms, syndromes of disorders, or phenotypes. All of these phenomena can be described in terms of clinical course and associations.  They can be studied with validated structured interviews and produce consistent results at the syndrome and severity level.  Apart from the symptoms they have little to say about subjective experience. It is phenomenology at the population level.

The first-person account of psychosis is a much different type of phenomenology.  It is focused on how that person is experiencing the psychosis. Do they feel different?  Does their world seem changed? Do familiar people seem like strangers? Has their day-to-day experience changed?  To borrow a question from the old Present State Exam –“Are you thinking clearly or is there is something interfering with your thinking?”  Even though these are unique experiences some researchers have developed semi-structured interviews to capture experiences in certain conditions.  The Examination of Anomalous World Experience (EAWE) is one example designed to capture subjective experience of people experiencing schizophrenia spectrum disorders. It has 75 items across 6 domains of subjective experience. 

The clinical interview in psychiatry combines elements of both forms of phenomenology – basically because physicians are all taught how to interview people around a central subjective theme called a chief compliant.  After doing many of these interviews of people with the same or similar diagnoses – it becomes apparent that no two people with the same diagnosis experience it the same way.  In psychiatry and neurology it is more complex because the substrate that has the problem is the same one that produces the conscious state and the patient’s subjective experience of it.  By clinical or semi structured interview – the focus is on psychopathology at the individual level and the effect on consciousness.   

How does all that apply to postpartum psychosis? There are good studies of postpartum psychosis and research groups with ongoing projects.  The Massachusetts General Hospital Postpartum Psychosis Project (MGHP3) is one research group that has published on a large cohort of women (N=248) with postpartum psychosis (PP) (17).  Data was collected by administration of the Mini Internation Interview for Psychotic Disorder Studies (MINI-PDS).  61.7% of the sample met criteria for a psychiatric disorder prior to an at the index episode of PP.  12.5% had a prior episode of psychosis.  Substance use disorders were not excluded from the sample to improve generalizability and 22.6% had a diagnosis of alcohol use disorder (AUD) or substance use disorder (SUD).  Most patient were hospitalized (74.4%), received medications (93%), and psychotherapy (65.89%).  Median time to return to psychiatric baseline was 25 weeks. This is the first time I have seen psychiatric baseline used in the literature as an outcome criteria, even though clinical psychiatrists have used this as a treatment standard for decades.  

Psychotic symptoms were well documented and there was significant variability in the duration of symptoms.  For 60.9% of subjects the symptoms lasted between 1 day and 1 month, 24% lasted form 1 month to 6 months, and 10.47% lasting greater than 6 months.  Half of the subjects said that their symptoms wax and wane.  The authors point out that periods of lucidity as possible and this may lead to a false impression that the patient is doing better than they really are. Since most of the subjects received atypical antipsychotics, the authors discuss the importance of determining subgroups that may need maintenance medication and others where the medication can be discontinued.    

The issue of whether PP develops into bipolar disorder was discussed.  Not all women go on to develop subsequent episodes, suggesting there may be a from that only occurs in the postpartum period.  The issue of prevention of these episodes in woman with a preexisting diagnosis of bipolar disorder was discussed and how that can be prevented with appropriate prophylactic treatment.   I would look to this group in the future for more state-of-the-art research on PP.  They appear to also have a genomics component.    

The question of child related delusions and their specificity for PP was discussed.  The authors conclude that paranoia directed at partners and infants safety and wellbeing were common and consistent with the idea that this may be a period of enhanced vulnerability.  I would see this paper as a critical resource for psychiatrists interested in this disorder both at a clinical and theoretical level.

A second paper is interesting in that it looks at women hospitalized on a Mother-Baby Inpatient unit in the Netherlands.  This group goes by the title Onderzoeksprogramma Postpartum Psychose Erasmus MC Rotterdam (OPPER) and they have previously published (18).  The sample size was 130 women.  I wrote a post on this setting a decade ago as an ideal resource for postpartum conditions.  Since then I am not aware of any similar treatment setting in the US.  One of the interesting aspects of this sample is that 48% of the subjects were admitted on an involuntary basis.  The standards described parallel most US standards for involuntary treatment of risk to self or others or inability to care for oneself.  17% of the sample had either obsessive concerns about harming the child or more or infanticidal thoughts.

This group used standardized questionnaires and rating scales to characterize psychopathology including the Structured Clinical Interview for DSM-IV Disorders (SCID), Young Mania Rating Scale (YMRS), Edinburgh Postpartum Depression Scale (EPDS), and Hamilton Rating Scale for Depression (HAM-D). That resulted in a total of 58 symptoms that were used to determine symptoms prevalence and generate profiles by statistical modeling (latent class analysis).  Anxiety, depression and delusions were the most common symptoms across all profiles.  A total of 11 symptoms were used to develop profiles anxiety, depression , melancholia, agitation, mania, atypical , disorganization, delusions, hallucinations, child-related, and catatonia.  From these symptoms a manic profile (34%), a depressive profile (41%), and an atypical profile (25%) were developed.  Dysphoric mania was more likely and the authors point out it is more prevalent in woman at baseline.  Patients in the manic and atypical categories were more likely to be treated on an involuntary basis. Like the MGH study remission rates were high (82-94%) with fastest remission in the manic group and slowest in the depressive group. The authors identified 2 cases of NMDA encephalitis in the group with disorientation, disturbance of consciousness, and disorganization suggesting it is important in the differential diagnosis of this disorder.

The authors of this paper make the compelling argument that PP is one of the few psychiatric disorders where the etiology (childbirth) is known. They point out that it is a severe disorder that frequently requires involuntary treatment, needs careful medical assessment, and although it seems like it is on the bipolar spectrum – it should not be included there too quickly.  Like the MGH group they point out that even with the profiles they developed they are not able to predict disease course and this would be a major advance in treatment.  

There are other papers that apply to the current case and similar cases in the last.  Resnick described cases of altruistic psychotic filicide associated with altruistic delusions.  The decisions are associated with thoughts that the child will be protected from harm from evil, criminal activity, or in some cases a specific family member that the mother has delusional concerns about.  In some cases, the child is seen as already affected by evil that is irreversible.  Death is the only way to protect the child but it makes sense only in the context of an alteration in consciousness.

To summarize, a category-based diagnosis is not a comprehensive explanation of behavior. That is the main reason psychiatrists are taught additional approaches to formulation of the current problem.  There is a general tendency of non-experts to lump all people with a similar diagnosis into the same category.  That is an error that most second year medical students recognize when they see the vast variations in diagnostic presentations, outcomes, and treatments.  In psychiatry, that variation is amplified greatly by all of the factors contributing to unique conscious states.

In forensic settings psychiatrists are called upon to present a diagnosis, a formulation, and comment on how both inform any statutory requirements for a defense or prosecution.  As a psychiatrist who has testified in hundreds of these hearings – the adversarial process is far from ideal.  A few examples include, a judge telling me what I can and cannot talk about, attorneys asking me questions they said they were not going to ask, rhetorical techniques by attorneys that they thought would shake me up, and questions that were clearly framed to distort the reality of the situation. All of those factors suggested to me that the only way real clinical psychiatry is expressed in court is if you have an expert witness who is familiar with all of that rhetoric and can ignore it.

The other critical piece is what can be done to educate the public as well as the jury.  Formal psychiatric training develops large categories that we need to cover in order to do a good job.  Thise categories exist diagnostically but also in the mental status exam (MSE) or direct examination of the patient.  For most forensic purpose the relevant categories are insight and judgment.  Both are critical in any postpartum case of filicide. That generally involves conclusory remarks based on connections with other MSE categories.  There is typically no description of a conscious state, but there might be discussion of other mitigating factors.  It is probably time to consider detailed discussion of how to include that component – not only in court but in the DSM in general.  Some of the other proposed inclusions are probably less important.

 

George Dawson, MD, DFAPA

 

References:

1:  Posner JB, Saper CB, Schiff ND, Plum F.  Plum and Posner’s Diagnosis of Stupor and Coma.  Oxford University Press, New York, 2007; 401 pp. 

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13:  Bellak L.  Basic aspects of ego function assessment. In: The Broad Scope of Ego Function Assessment.  Bellak L, Goldstein LA (eds).  John Wiley and Sons, New York, 1984: 6-30.

14:  Schneider, K. (1959), Clinical Psychopathology, pp. 100, 132–134

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16:  Parnas J, Henriksen MG. Disordered self in the schizophrenia spectrum: a clinical and research perspective. Harv Rev Psychiatry. 2014 Sep-Oct;22(5):251-65. doi: 10.1097/HRP.0000000000000040. PMID: 25126763; PMCID: PMC4219858.

17:  Cohen LS, Arakelian M, Church TR, Dunk MM, Gaw ML, Yoon HE, Kobylski LA, Vanderkruik R, Freeman MP. The phenomenology of postpartum psychosis: preliminary findings from the Massachusetts General Hospital Postpartum Psychosis Project. Mol Psychiatry. 2025 Jun;30(6):2537-2544. doi: 10.1038/s41380-024-02856-3. Epub 2024 Dec 6. PMID: 39643690.

18:  Kamperman AM, Veldman-Hoek MJ, Wesseloo R, Robertson Blackmore E, Bergink V. Phenotypical characteristics of postpartum psychosis: A clinical cohort study. Bipolar Disord. 2017 Sep;19(6):450-457. doi: 10.1111/bdi.12523. Epub 2017 Jul 12. PMID: 28699248.

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21:  Resnick PJ. Child murder by parents: a psychiatric review of filicide. Am J Psychiatry. 1969 Sep;126(3):325-34. doi: 10.1176/ajp.126.3.325. PMID: 5801251.