Schizophrenia: A Neurodevelopmental Perspective

Diverse lines of research suggest that schizophrenia is a genetically influenced neurodevelopmental disorder. Family, twin, and adoption studies suggest that most cases of schizophrenia involve a genetic diathesis that is necessary but not sufficient for development of the disorder. Histological, neuroimaging, and neuropsychological findings converge in providing evidence for medial-temporal and frontal lobe dysfunction that likely predates the onset of psychosis. Behavioral phenomenology and neurobiology suggest that dopamine plays a crucial moderating role between these structural abnormalities and functional impairment. Recently, investigators have used animal models and clinical syndromes to integrate these findings into neurodevelopmental models of schizophrenia that hold great potential for yielding etiological insight.     

Verbal Declarative Memory Dysfunction in Schizophrenia: From Clinical Assessment to Genetics and Brain Mechanisms

The recent literature on the neuropsychology of schizophrenia has emphasized memory deficits as a key area of impairment. Abnormalities in the medial temporal lobe, a brain region crucial for long-term memory formation, have also consistently been reported. We conducted a comprehensive review of verbal declarative memory (VDM) in schizophrenia with the aim of systematically addressing the nature of this impairment. We conclude that verbal declarative memory is significantly impaired in schizophrenia and is largely accounted for by deficits in the encoding stage. Subtle impairments in increased rates of forgetting are present, but are mild compared with those in amnestic disorders. Impairment in other cognitive domains studied thus far (e.g., attention), medication effects, or fluctuations in symptoms do not completely account for the deficit. VDM is among the most impaired neurocognitive domains in schizophrenia (along with attention and executive functions). Milder encoding deficits are present in high-risk subjects and non-psychotic relatives of individuals with schizophrenia suggesting that components of the deficit are associated with a genetic vulnerability to the illness, and are independent of the frank psychotic illness. Furthermore, VDM is observed in individuals experiencing their first-psychotic episode and it remains fairly consistent over time. Preliminary imaging studies and other work suggest abnormalities in prefrontal-hippocampal processing networks. Future work should emphasize delineating specific information processing components contributing to the deficit. This would allow imaging studies to determine which brain regions contribute to specific information processing deficits in schizophrenia.     

Prospective memory,working memory,planning, and attention in schizophrenia and bipolar disorder: A comparative study

There is a need to study prospective memory (PM) and its relationship with aspects of frontal lobe functioning in schizophrenia and bipolar disorder. The study aims to investigate event‐based (EB) and time‐based (TB) PM functioning in the two groups, and its association with working memory, planning, and attention. A word categorisation task was developed to assess PM functioning among 90 participants (schizophrenia, bipolar disorder, and a control group). Frontal lobe functioning was assessed using Tower of London, N‐Back test, and triads test. Mean comparisons revealed significantly higher impairment in TB PM in comparison to EB PM in both the clinical groups. Significant relationship between PM and frontal lobe impairment was found. Relationship between PM and frontal lobe deficits in the clinical groups emphasises the need to include its assessment at an early stage and to develop PM rehabilitation strategies to improve the quality of living.     

How semantic content of stimuli works on episodic memory processes in negative schizophrenia: Evidence from picture recognition

IntroductionEven though episodic memory is impaired in schizophrenia, semantic processing strategies can improve patients’ performance. However, it is less clear if negative schizophrenia patients can benefit from semantic strategies, and if both familiarity and recollection processes can be enhanced in patients with schizophrenia.ObjectiveThe aim of this study was to investigate the possibility for negative schizophrenia patients to enhance their familiarity and/or recollection processes in the presence of concrete images.MethodA recognition memory task using concrete versus abstract images as stimuli was designed to assess the performance of schizophrenia patients for single item recognition and the recollection of spatial context, allowing us to calculate the estimates of familiarity and recollection processes. Thirty-six patients with schizophrenia and 18 healthy individuals participated to the study. Schizophrenia patients were divided into two groups according to their scores on the negative scale of the Positive and Negative Syndrome Scale for Schizophrenia (PANSS).ResultsResults showed that, while healthy participants enhanced their recollection estimates in the presence of concrete images, both schizophrenia groups could enhance their familiarity estimates.ConclusionSemantic strategies are helpful to promote successful familiarity process in schizophrenia patients, independently from clinical dimension of negativity. However, recollection process seems not to respond to such strategies.     

The Fear of Understanding Schizophrenia and Iatrogenic Myths

Empirically, psychotherapy with a competent therapist is the optimal, but rarely offered treatment, for schizophrenia. Medication or ECT produces less disturbing, lifelong cripples. Within 25 years one-third spontaneously recover completely (unless they stay on medication), and another third socially recover. Nazi Germany sterilized and annihilated patients without decreasing mental disorders in the next generation. Schizophrenia is a terror syndrome. The therapist must create a therapeutic alliance by creating hope and tolerating not understanding. Hallucinations are waking dreams. Delusions are transferences, defenses against pseudohomosexuality, family-specific meanings, or attempts to make sense out of strange experiences.     

Synthetiki Psychotherapy: An Integrative Psychotherapy for Individuals with Schizophrenic Symptoms

During the past 22 years, the author has developed an integrative psychotherapeutic model, called Synthetiki Psychotherapy (from the Greek word synthesis), for the treatment of individuals with schizophrenic symptoms. It has been influenced by certain philosophical and ethical principles, by ancient and modern Greek civilization and culture, and by the psychotherapy integration movement, and has been tested through research at the Laboratory of Clinical and Social Psychology of the University of Crete, Greece. The principles of Synthetiki Psychotherapy are presented and discussed.     

Cultural Mistrust and the Clinical Diagnosis of Paranoid Schizophrenia in African American Patients

This study examined agreement between clinical diagnoses and research diagnoses of schizophrenia for a sample of African American patients recently admitted to a psychiatric hospital. It also examined the association of cultural mistrust with disagreement between clinical diagnoses and research diagnoses of the paranoid subtype of schizophrenia. Complete data was available for 118 (77%) of the 154 cases from the original sample. Agreement among the different sources of diagnoses was poor in 5 out of 6 comparisons. The lack of agreement can be attributed, in part, to the fact there were significantly more cases of schizophrenia using clinical diagnoses than those using SCID or best estimate methods. Contrary to the hypothesis, however, level of cultural mistrust did not predict the excess in clinical diagnoses of paranoid schizophrenia. Cultural mistrust was positively associated with the odds of a diagnosis of paranoid schizophrenia by the best estimate method. The implications of the results for the diagnosis and treatment of African American patients are discussed.     

Elderly offenders in a maximum security mental hospital

Elderly offenders aged 60 and above constitute less than 8% of the population in a maximum security mental hospital. These offenders fall into 2 groups: 1) first admission at or after the age of 50 and 2) first admission before 50. Fewer first time offenders committed homicide in the first group than those in the second group. Neuropsychiatric disturbance and sex offending was common among male first time offenders in the first group; in contrast, schizophrenia and violent offending against persons was found more often in the second group. It is argued that elderly first time offenders should be given adequate neuropsychiatric assessment. © 1995 Wiley-Liss, Inc.     

“Hearing voices”: Auditory hallucinations as failure of top‐down control of bottom‐up perceptual processes

Auditory hallucination is a key characteristic of schizophrenia that seriously debilitates the patient, with consequences for social engagement with others. Hallucinatory experiences are also observed in healthy individuals in the general population who report “hearing voices” in the absence of an external acoustic input. A view on auditory hallucinations and “hearing voices” is presented that regards such phenomena as perceptual processes, originating from speech perception areas in the left temporal lobe. Healthy individuals “hearing voices” are, however, often aware that the experience comes from inner thought processes, which is not reported by hallucinating patients. A perceptual model can therefore, not alone explain the difference in the phenomenology of how the “voices heard” are attributed to either an inner or outer cause. An expanded model is thus presented which takes into account top‐down cognitive control, localized to prefrontal cortical areas, to inhibit and re‐attribute the perceptual mis‐representations. The expanded model is suggested to be empirically validated using a dichotic listening speech perception paradigm with instructions for top‐down control of attention focus to either the right or left side in auditory space. It is furthermore suggested to use fMRI to validate the temporal and frontal lobe neuronal correlates of the cognitive processes involved in auditory hallucinations.     

Emotional Abuse and Psychosis: A Recent Review of the Literature

This article evaluates the published empirical findings on childhood emotional abuse and its proposed relationship with psychotic symptoms. Research and governmental policy indicates that emotional abuse is present in all forms of abuse and neglect, suggesting it is the form of abuse most frequently linked to mental health problems. Literature searches were conducted in 3 peer-reviewed electronic databases and relevant papers were reviewed. Results suggest childhood emotional abuse is statistically related to psychosis in adulthood. This adds tentative support to the hypothesis that emotional abuse is related to psychotic experiences; in particular to hallucinations and persecutory delusions. A number of studies also provide tentative support to the dose–response effect proposed between cumulative trauma and a greater risk of positive psychotic symptoms.