The research of the Universitat de València, INCLIVA and CIBER manifests that these experiences can contribute to the appearance of serious psychiatric disorders such as psychosis and schizophrenia. The results of the research have been published in Progress in Neuropsychopharmacology & Biological Psychiatry

The research has been led by Juan Nácher, full-time university professor of Cell Biology and researcher of the Institut Universitari d’Investigació en Biotecnologia i Biomedicina (BIOTECMED) of the Universitat de València, team leader of the Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM) and member of the Research Group in Psychiatry and neurodegenerative diseases of INCLIVA.

The findings of the research show the impact of the unfavourable experiences during the childhood and the adolescence, such as abuse, neglect or harassment, can contribute to the appearance of serious psychiatric disorders such as psychosis and schizophrenia. The work has been developed by a multidisciplinary team that includes professionals in psychiatry, neurobiology, genetics, neuroimaging and psychology. The obtained results are really relevant to comprehend how the unfavourable experiences early in life influence over the development of the brain and can derivate in alterations of the neuronal circuits that could potentially turn into alterations in behaviour and cognition.

The analysis of patients with psychotic disorders such as schizophrenia has manifested the existence of alterations in the structure of different brain regions, among them the thalamus. This deep region of the brain constituted by many nucleus with specific connections that participates in the processing of the information that arrives through the senses, but is also gets involved in phenomena such as conscience or sleep regulation, among others. The thalamus is completely developed during the childhood and the adolescence, therefore, it is specially susceptible to changes that occur during this period of our life. The adversities in childhood could affect in the development and potentially contribute to psychosis.

“In fact, recent studies in our laboratory, using animal models of schizophrenia that entail unfavourable experiences during the childhood and the adolescence, show really important alterations in the thalamus structure. These alterations are particularly relevant in inhibiting neurons of the thalamus and also affect the molecules related to its plasticity. The role of inhibiting neurons, is essential in the thalamus function, since they coordinate and synchronise the functioning of this region of the brain. Furthermore, there is evidence that these inhibiting neurons are altered in the brain of schizophrenia patients”, explains Juan Nácher.

“In previous studies of the Research Group it was discovered that the volume and the shape of the thalamus and some of the nucleus were found reduced in chronic patients of schizophrenia, but it was not know if it was product of the long-term development of the disease”, adds the researcher.

In this study the researchers explored, using brain pictures obtained with magnetic resonance imaging, if these alterations in the volume of the thalamus and its nucleus were also present in the debut of the disease with the first psychotic episode (PEP). Furthermore, it was checked if these alterations in the structure of the thalamus were related to early traumatic events.

To realise this study, patients with PEP and healthy controls with the same age, were recruited and subjected to structural magnetic resonance imaging of 3 T and to a psychological evaluation that included a questioner of childhood trauma. After this, the thalamus shape was analysed and the segment in the many nucleus to evaluate their volume. Furthermore, it was analysed in the blood the expression of different genes related to the neuronal plasticity of the thalamus and psychosis.

“The results showed volumetric reductions considering all the thalamus and the specific nucleus (posterior side, side geniculate, medial geniculate, ventrolateral, centromedial, anteriorventral, mediodorsal and pulvinar). Some of these nucleus are directly related to sensorial perception, particularly sight and hearing, and their alterations could be related to hallucinations that these patients frequently suffer. Other nucleus are implicated in superior cognitive functions that also can be found affected in the psychosis. It was also observed a significant association between some unfavourable experiences like neglect during childhood and the volume of the thalamus and some of the nucleus. Another interesting aspect is that researchers could detect in the patients alterations in the expression of genes related with neuronal plasticity of the thalamus and psychosis. Furthermore, these changes were correlated with anomalies in the volume of the thalamus and some constituent nucleus”, sums up Nácher.

 “This is the first work in which we have combined neuroimaging data with genetic expression data and with analysis of the impact of the unfavourable experiences in the first periods of life”, highlights Juan Nácher, who in conclusion, affirms that “this study links the volume of the thalamus nucleus with childhood adversities in the first psychosis episodes and underlines the changes in the expression of related molecules with the neuronal plasticity of the thalamus and its correlation with the volumes of the thalamus nucleus”.

Article:

https://www.sciencedirect.com/science/article/pii/S0278584625001253?via%3Dihub