Igor Branchi

Igor Branchi is Senior Researcher and Group leader at the Center for Behavioral Sciences and Mental Health, Istituto Superiore di Sanità/Italian Institute of Health, Rome, Italy and visiting Professor of Behavioral biology at the University of Rome Sapienza. He is Past-president of the European Brain and Behaviour Society. His main research interest is on the application of an integrative approach, spanning from epigenetics to behavior and the living environment, to investigate the neural bases of psychiatric disorders and the relative therapeutic strategies. He is also interested in complexity science and philosophical considerations on the effectiveness of scientific approaches aimed at understanding the central nervous system and bridging brain and behavior. Current efforts are directed towards the study of the interplay between neural and behavioral plasticity and contextual factors, such as stress and the quality of living conditions. Special attention is paid to drug x environment interactions. His current approach deals with clinical investigations aimed at developing metematical models to measure plasticity and at exploring factors determining the efficacy of treatments affecting plasticity, such as antidepressant and anti-inflammatory drugs.

Join us

International Ettore Majorana School

Recentering neuroscience on behavior: 

a brain-body-environment integrated approach

9-14 November 2024

Erice, Sicily, Italy

Among Igor's main research activities and contributions:

The double-edged sword of neural plasticity

High plasticity level induced by drugs, such as serotoninergic antidepressants and psychedelics, is not beneficial per se. It renders the brain and behavior more susceptible to change according to contextual factors, such as the living conditions. Therefore, high plasticity is therapeutic when combined with favorable context achieved through psychotherapy or environmental interventions. 


A mathematical formula of plasticity: predicting the transition from psychopathology to wellbeing

I have proposed a mathematical formula to assess plasticity – i.e., the susceptibility to change – to identify, at baseline, which individuals or populations are more likely to modify their behavioral outcome according to therapies or contextual factors. We have demonstrated that this approach is effective in predicting which depressed patients will be able to improve their depressive condition.


Breaking free from the inflammatory trap of depression: regulating the interplay between immune activation and plasticity to foster mental health

Any deviation toward an extreme immune activation or suppression leads to a dysregulation in the molecular machinery underlying neural plasticity. Therefore, pro–inflammatory conditions in depressed patients are associated with impaired plasticity, limiting the potential to recover. However, reinstating plasticity does not lead to an improvement per se but increases the likelihood of recovery. Therefore, combining the normalization of immune activity with environmental conditions promoting wellbeing is critical to achieve a beneficial outcome.  


The interface principle: behavior as a privileged level of control of brain functioning

Behavior and the associated mental states are the interface between the central nervous system and the living environment. Since, in any system, the interface is a key regulator of system organization, behavior is proposed as a unique and privileged level of control and orchestration of brain structure and activity. This view has relevant scientific and clinical implications. First, the study of behavior represents a singular starting point for the investigation of neural activity. Second, behavioral changes, accomplished through psychotherapy or environmental interventions, are expected to have the highest impact to reorganize the human mind and achieve a solid and long-lasting improvement in mental health.


Uncovering the determinants of brain functioning, behavior and their interplay in the light of context

I have proposed the Context theory of constrained systems that reconsiders the relative role of contextual factors and of the genetic, molecular and neural substrates in determining brain functioning and behavior. This framework entails that, first, context is the main driver of behavior and mental states. Second, substrates, from genes to brain areas, have no direct causal link to complex behavioral responses as they can be combined in multiple ways to produce the same response and different responses can impinge on the same substrates. Third, context and biological substrates play distinct roles in determining behavior: context drives behavior, substrates constrain the behavioral repertoire that can be implemented. Fourth, since behavior is the interface between the central nervous system and the environment, it is a privileged level of control and orchestration of brain functioning. These concepts are illustrated through the Kitchen metaphor of the brain.