Auditory hallucinations (AHs) are certainly the most emblematic experiences in schizophrenia, but visual hallucinations (VHs) are also commonly observed in this developmental psychiatric disorder. Notably, several studies have suggested a possible relationship between the clinical variability in hallucinations′ phenomenology and differences in brain development/maturation. In schizophrenia, impairments of the hippocampus, a medial temporal structure involved in mnesic and neuroplastic processes, have been repeatedly associated with hallucinations, particularly in the visual modality. However, the possible neurodevelopmental origin of hippocampal impairments in VHs has never been directly investigated. A classic marker of early atypical hippocampal development is incomplete hippocampal inversion (IHI). In this study, we compared IHI patterns in healthy volunteers, and two subgroups of carefully selected schizophrenia patients experiencing frequent hallucinations: (a) those with pure AHs and (b) those with audiovisual hallucinations (A+VH). We found that VHs were associated with a specific IHI pattern. Schizophrenia patients with A +VH exhibited flatter left hippocampi than patients with pure AHs or healthy controls. This result first confirms that the greater clinical impairment observed in A+VH patients may relate to an increased neurodevelopmental weight in this subpopulation. More importantly, these findings bring crucial hints to better specify the sensitivity period of A+VHrelated IHI during early brain development.

Medical advances in assisted reproductive technology have created new ways for transgender persons to become parents outside the context of adoption. The limited empirical data does not support the idea that trans-parenthood negatively impacts children’s development. However, the question has led to lively societal debates making the need for evidence-based studies urgent. We aimed to compare cognitive development, mental health, gender identity, quality of life and family dynamics using standardized instruments and experimental protocols in 32 children who were conceived by donor sperm insemination (DSI) in French couples with a cisgender woman and a transgender man, the transition occurring before conception. We constituted two control groups matched for age, gender and family status. We found no significant difference between groups regarding cognitive development, mental health, and gender identity, meaning that neither the transgender fatherhood nor the use of DSI had any impact on these characteristics. The results of the descriptive analysis showed positive psycho-emotional development. Additionally, when we asked raters to differentiate the family drawings of the group of children of trans-fathers from those who were naturally conceived, no rater was able to differentiate the groups above chance levels, meaning that what children expressed through family drawing did not indicate cues related to trans-fatherhood. However, when we assessed mothers and fathers with the Five-Minute Speech Sample, we found that the emotions expressed by transgender fathers were higher than those of cisgender fathers who conceived by sex or by DSI. We conclude that the first empirical data regarding child development in the context of trans-parenthood are reassuring. We believe that this research will also improve transgender couple care and that of their children in a society where access to care remains difficult in this population. However, further research is needed with adolescents and young adults.

Background The prevalence and clinical significance of hallucinatory experiences among children below 7 years of age remain unknown. We aimed to determine the independent influences of sensory deficits, the presence of an imaginary companion and metacognition on hallucinatory experiences. We assumed that hallucinatory experiences were associated with (a) sensory deficits, (b) the presence of an imaginary companion (IC) and (c) metacognition defaults (i.e. first‐ and second‐order theory of mind default). Methods All children in the third year of preschool from a region of Northern France underwent medical screening. We compared the prevalence rates of visual, auditory and audio‐visual hallucinatory experiences based on (a) the presence of visual or auditory deficits, (b) the actual presence of an IC and (c) metacognition. The analyses were adjusted for age. Results A total of 1,087 children aged between 5 and 7 years were included. The prevalence rates of auditory, visual and audio‐visual hallucinatory experiences were 15.8%, 12.5% and 5.8%, respectively. The prevalences of different types of hallucinatory experiences were not significantly different according to sensory deficit. The prevalences of all types of hallucinatory experiences were significantly higher among children with an IC and among children with metacognition defaults. Conclusions The association between hallucinatory experiences and sensory deficits might concern only long‐lasting deficits. The association with the presence of an IC confirms experimental findings of the likelihood of perceiving words among meaningless auditory stimuli. Relations between hallucinatory experiences and theory of mind need to be addressed in longitudinal studies.

SummaryPrevious reports suggest that adverse events during childhood could be related to an array of psychiatric problems. Here, we question the relationship between childhood traumatic experiences and the sensory complexity of hallucinations in a cohort of 75 children and adolescents. We evidence a positive link between the number of sensory modalities involved in hallucinations and history of childhood trauma, even after controlling for the co-occurrence of suicidal ideation or the number of ICD-10 diagnoses. These findings support initiatives in which a routine exploration of traumatic events in childhood is performed when multimodal hallucinations are present.