Limited Intermittent Psychotic Symptoms Research Articles

Auditory P300 in individuals clinically at risk for psychosis

Background Alterations of the auditory evoked P300 potential are among the most reliable biological markers of schizophrenia. The aim of this study was to assess the amplitude, latency, and topography of the P300 in individuals at clinical high risk for psychosis. Methods P300 event-related potentials were acquired with an auditory oddball paradigm from 100 patients putatively in an early initial prodromal state (EIPS) for psychosis or in a late initial prodromal state (LIPS), according to the criteria of the German Research Network on Schizophrenia, and from 40 healthy controls comparable with respect to age, gender, and estimated verbal IQ. Results In the LIPS group, P300 amplitude was significantly smaller at midline and left hemispheric electrodes in comparison with controls. In the EIPS group, P300 amplitude was significantly reduced at a left temporoparietal site (TP7). A family history of schizophrenia was associated with smaller posterior P300 amplitudes in high-risk individuals. Midline P300 amplitudes were smaller in LIPS who had experienced already brief limited intermittent psychotic symptoms. Conclusion Smaller P300 amplitudes are present prior to a putative onset of psychosis in high-risk individuals. Selective left temporoparietal amplitude deficits may indicate a trait-like abnormality whereas deficits at sagittal midline electrodes may be partly determined by the changes that underlie the appearance of psychotic symptoms. P300 amplitude may be associated with left superior temporal lobe maturation abnormalities followed by further functional impairments later in life. Our follow-up study will reveal whether P300 amplitude alterations predict psychosis and help to targeting early intervention.

Early detection and intervention of psychosis. A review

The vulnerability and hybrid models for the onset of psychosis are presented. Familial liability, perinatal and developmental factors, and decreased cognitive performance associate with psychosis in adolescence and young adulthood. Genetic predisposition connected with behavioural deviances and/or mental symptoms associate with psychotic development so strongly that monitoring and intervention are indicated. Especially, in families where one or both parents or other family members are severely mentally ill, early family-centred assessments and interventions is needed. Together with familial psychosis, deficits in adolescent and young adult social development indicate thorough assessment, intensive monitoring and often also preventive interventions. During the prodromal phase of psychosis, patients often display unspecific symptoms, such as anxiety and depression, personality disorders, abuse of alcohol or drugs. Social decline, possibly associated with neurocognitive deficits, frequently occurs in the prodromal phase or in the early course of schizophrenia. Among help-seeking patients, occurrence of the Basic Symptoms represent the early initial prodromal state, while the late initial prodome state includes attenuated psychotic symptoms, brief limited intermittent psychotic symptoms, and a first degree relative with psychotic disorder, or a schizotypal personality disorder, together with decrease global functioning. These patients suffer also from other mental symptoms and functional decline, and are clearly in need of psychiatric assessment and treatment. Intervention trials have shown that patients suffering from prodromal syndromes can be successfully treated, and onset of psychosis prevented or delayed. However, more large-scale studies and clinical case descriptions of treatment of patients with sub-threshold psychotic symptoms are needed.

Perceptual organization in first episode schizophrenia and ultra-high-risk states

Deficits in perceptual organization have been consistently reported in schizophrenia, as has an association between these deficits, disorganized symptoms, and poorer premorbid functioning and prognosis, suggesting that they may be an index of illness severity or progression. It is unclear, however, whether the impairment is present at, or before the first psychotic episode. This study examined perceptual organization in young people considered to be at high-risk for schizophrenia, defined by the “close-in” strategy [Yung, A.R., McGorry, P.D., McFarlane, C.A., Jackson, H.J., Patton, G.C., Rakkar, 1996. Monitoring and care of young people at incipient risk of psychosis. Schizophrenia Bulletin, 22, 283–303]. The high-risk group ( n = 70) was compared to first-episode patients ( n = 54), and nonpatients ( n = 24) using a task with known sensitivity to perceptual organization deficits in schizophrenia, and whose scores have predicted long-term outcome and disorganized symptomatology in past studies [Knight, R.A., Silverstein, S.M., 1998. The role of cognitive psychology in guiding research on cognitive deficits in schizophrenia. In Lenzenweger, M., Dworkin, R.H., (Eds.), Origins and Development of Schizophrenia: Advances in Experimental Psychopathology. APA Press, Washington DC, pp. 247–295.; Silverstein, S.M., Knight, R.A., Schwarzkopf, S.B., West, L.L., Osborn, L.M. Kamin, D., 1996b. Stimulus configuration and context effects in perceptual organization in schizophrenia. Journal of Abnormal Psychology 105, 410–420.; Silverstein, S.M., Schenkel, L.S., Valone, C., Nuernberger, S., 1998a. Cognitive deficits and psychiatric rehabilitation outcomes in schizophrenia. Psychiatric Quarterly 69, 169–191.; Silverstein, S.M., Bakshi, S., Chapman, R.M., Nowlis, G., 1998b. Perceptual organization of configural and nonconfigural visual patterns in schizophrenia: effects of repeated exposure. Cognitive Neuropsychiatry 3, 209–223]. There were no differences between groups, and the first-episode group demonstrated non-significantly more sensitivity to stimulus organization than the other groups. When the high-risk group was broken down into its 3 subgroups (A—family history of psychotic illness and recent drop of 30+ points in the GAF scale; B—history of attenuated psychotic symptoms; C—brief limited intermittent psychotic symptoms), only group A demonstrated evidence of impairment, but this group differed significantly only from first- and young, later-episode schizophrenia patients, not from nonpatients. These findings are consistent with recent data on pre-attentive processes in schizophrenia which indicate that performance is not impaired and may even be enhanced, early in the illness, with dysfunctions beginning with increased chronicity.

Severity of baseline positive symptoms predicts psychosis in adolescents prodromal for schizophrenia

Prodromal symptoms of bipolar disorder (BD) and early onset schizophrenia spectrum disorder (EOSSD) overlap. To date, there has been no study directly comparing the prodromal stage of both disorders. Thus, the current study is aimed at determining which prodromal symptom clusters differentiate BD and EOSSD. One hundred twenty one adolescents (33 BD-1, 30 EOSSD, 58 healthy controls) were evaluated for the presence of 79 prodromal symptoms, divided into 7 prodromal symptom clusters. Great than 2 subsyndromal manic symptoms and ADHD comorbidity were significantly more specific for BD than schizophrenia; brief limited intermittent psychotic symptoms (BLIPS) were more likely to be part of EOSSD. In contrast, attenuated psychotic symptoms, and negative symptoms were not specifically related to the diagnosis of EOSSD. In conclusion, subsyndromal manic symptoms, BLIPS, and ADHD might be useful for predicting the trajectory of an emerging affective disorder versus schizophrenia and thus valuable for early detection, and intervention strategies.