Maltreatment linked to altered brain structure and spontaneous thought patterns in children, study finds

A new study has found that children exposed to maltreatment tend to have fewer positive thoughts and are more likely to develop ruminative thought patterns compared to children who were not mistreated. They also had reduced thickness of the subcallosal cingulate cortex region of the brain, a characteristic associated with difficulties in emotion regulation and depressive symptoms. The paper was published in Journal of Child Psychology and Psychiatry.

Childhood maltreatment encompasses any act or series of acts, whether by commission or omission, by a parent, caregiver, or another individual in a caregiving role, that causes harm, potential harm, or threat of harm to a child. It includes physical, sexual, and emotional abuse, as well as neglect—both physical neglect and neglect of a child’s emotional needs. The effects of childhood maltreatment can be profound and long-lasting, impacting an individual’s physical and mental health well into adulthood, and influencing their quality of life, relationships, and overall wellbeing.

Childhood maltreatment is one of the strongest and the most widespread risk factors for the development of the major depressive disorder. Studies have particularly pointed out that unwanted, repetitive thoughts oriented towards past events and shaded by negative affect might be a link between childhood maltreatment and depression. These thought patterns are referred to as ruminative. Being immersed in them for prolonged periods is called rumination.

Researchers assess rumination by examining spontaneous thoughts—that is, self-generated thoughts. Individuals report these thoughts, and if they are repetitive, negatively affect-laden, and frequently focused on the same past events, they are considered indicative of rumination.

In their new study, Ferdinand Hoffmann and his colleagues sought to explore the spontaneous thought patterns and their characteristics in children aged 6 to 12 years. They aimed to compare these patterns between children who had experienced childhood maltreatment and those who had not. The researchers hypothesized that maltreated children would be more susceptible to rumination and that there could be neurobiological differences between the groups, particularly in terms of depression-associated characteristics. Specifically, they believed that maltreated children might exhibit lower cortical thickness in the subcallosal cingulate cortex and higher cortisol levels.

The subcallosal cingulate cortex is crucial for emotion and stress response regulation. Research indicates that reduced thickness in this region may suggest a vulnerability to emotional dysregulation and could potentially serve as a biomarker for the severity of depressive symptoms or the effectiveness of treatment interventions. Cortisol, a steroid hormone known as the “stress hormone,” increases in response to stress and low blood glucose levels. High cortisol levels can signal physical or psychological stress and are linked to various adverse health conditions.

The study involved 96 maltreated children, recruited from child welfare and protection services, and 87 healthy, non-maltreated children, with an average age of 9 years.

The researchers utilized the Maltreatment Classification system to quantify the level of maltreatment each child had experienced. They also evaluated the children’s cognitive abilities using the Snijders-Oomen Nonverbal Intelligence Tests and assessed their socioeconomic status with the Winkler and Stolzenberg Index, based on educational attainment, occupational qualifications, status, and household net income. Furthermore, the children underwent assessments for depressive symptoms and participated in magnetic resonance imaging.

Additionally, the children completed an assessment of depressive symptoms (the Center for Epidemiological Studies Depression Scale for Children), a screening interview for the diagnosis of depression (Schedule for Affective Disorders and Schizophrenia for school-age children, Kiddie-SADS Present and Lifetime Version), and underwent magnetic resonance imaging.

Results showed that maltreated children had significantly lower cognitive ability and lower socioeconomic status compared to healthy children. They also had more pronounced depressive symptoms.

While no initial differences were observed in the thickness of the subcallosal cingulate cortex, after adjusting for cognitive ability and socioeconomic status, a notable difference emerged, showing reduced thickness in maltreated children. The most severely maltreated children exhibited the least cortical thickness in this brain region. No differences in cortisol levels were found between the groups.

Analysis of spontaneously generated thoughts demonstrated that maltreated children had significantly fewer positive thoughts, and their negative thoughts were more interconnected. Their negative self-perceptions and outlook on the future were tightly linked.

“This study using a novel network analytic approach to SGTs [self-generated thoughts] provides evidence that maltreated children show maladaptive, rumination-like thought patterns within their thought network that can be identified already in middle childhood,” the researchers concluded. “These are characterized by greater connectiveness of negatively valenced thoughts with self-related and future-and past oriented thoughts, greater centrality of other-related and past-oriented thoughts, and an absence of future-self thought coupling.”

“Rumination-like thought patterns in maltreated children were associated with depressive symptoms, as well as with neurobiological and physiological markers of depression and rumination, in terms of SCC [subcallosal cingulate cortex] thickness and cortisol levels.”

The study sheds light on the psychological and physiological factors associated with childhood mistreatment. However, it should be noted that the study design does not allow any cause-and-effect inferences to be made from these data.

The paper, ”Children with maltreatment exposure exhibit rumination-like spontaneous thought patterns: association with symptoms of depression, subcallosal cingulate cortex thickness, and cortisol levels,” was authored by Ferdinand Hoffmann, Roman Linz, Nikolaus Steinbeis, Martin Bauer, Felix Dammering, Claudia Lazarides, Heiko Klawitter, Lea Bentz, Sonja Entringer, Sibylle M. Winter, Claudia Buss, and Christine Heim.