The approach-avoidance conflict (AAC), i.e. the competing tendencies to undertake goal-directed actions or to withdraw from everyday life challenges, stands at the basis of humans' existence defining behavioural and personality domains. Gray's Reinforcement Sensitivity Theory posits that a stable bias toward approach or avoidance represents a psychopathological trait associated with excessive sensitivity to reward or punishment. Optogenetic studies in rodents and imaging studies in humans associated with cross-species AAC paradigms granted new emphasis to the hippocampus as a hub of behavioural inhibition. For instance, recent functional neuroimaging studies show that functional brain activity in the human hippocampus correlates with threat perception and seems to underlie passive avoidance. Therefore, our commentary aims to (i) discuss the inhibitory role of the hippocampus in approach-related behaviours and (ii) promote the integration of functional neuroimaging with cross-species AAC paradigms as a means of diagnostic, therapeutic, follow up and prognosis refinement in psychiatric populations.

Cognitive deficits are prevalent in bipolar disorder even during the euthymic phase, having a negative impact on global functioning and quality of life. As such, more and more mental health professionals agree that neuropsychological assessment should be considered an essential component of the clinical management of bipolar patients. However, no gold standard tool has been established so far. According to bipolar disorder experts targeting cognition, appropriate cognitive tools should be brief, easy to administer, cost-effective and validated in the target population. In this commentary, we critically appraised the strengths and limitations of the tools most commonly used to assess cognitive functioning in bipolar patients, both for screening and diagnostic purposes.

Early-life adverse events or childhood adversities (CAs) are stressors and harmful experiences severely impacting on a child's wellbeing and development. Examples of CAs include parental neglect, emotional and physical abuse and bullying. Even though the prevalence of CAs and their psychological effects in both healthy and psychiatric populations is established, only a paucity of studies have investigated the neurobiological firms associated with CAs in bipolar disorder (BD). In particular, the exact neural mechanisms and trajectories of biopsychosocial models integrating both environmental and genetic effects are still debated. Considering the potential impact of CAs on BD, including its clinical manifestations, we reviewed existing literature discussing the association between CAs and brain alterations in BD patients. Results showed that CAs are associated with volume alterations of several grey matter regions including the hippocampus, thalamus, amygdala and frontal cortex. A handful of studies suggest the presence of alterations in the corpus callosum and the pre-fronto-limbic connectivity at rest. Alterations in these regions of the brain of patients with BD are possibly due to the effect of stress produced by CAs, being hippocampus part of the hypothalamus–pituitary–adrenal axis and thalamus together with amygdala filtering sensory information and regulating emotional responses. However, results are mixed possibly due to the heterogeneity of methods and study design. Future neuroimaging studies disentangling between different types of CAs or differentiating between BD sub-types are needed in order to understand the link between CAs and BD.

According to the social brain hypothesis, the human brain includes a network designed for the processing of social information. This network includes several brain regions that elaborate social cues, interactions and contexts, i.e. prefrontal paracingulate and parietal cortices, amygdala, temporal lobes and the posterior superior temporal sulcus. While current literature suggests the importance of this network from both a psychological and evolutionary perspective, little is known about its neurobiological bases. Specifically, only a paucity of studies explored the neural underpinnings of constructs that are ascribed to the social brain network functioning, i.e. objective social isolation and perceived loneliness. As such, this review aimed to overview neuroimaging studies that investigated social isolation in healthy subjects. Social isolation correlated with both structural and functional alterations within the social brain network and in other regions that seem to support mentalising and social processes (i.e. hippocampus, insula, ventral striatum and cerebellum). However, results are mixed possibly due to the heterogeneity of methods and study design. Future neuroimaging studies with longitudinal designs are needed to measure the effect of social isolation in experimental v. control groups and to explore its relationship with perceived loneliness, ultimately helping to clarify the neural correlates of the social brain.

Since its discovery in 1997, the default mode network (DMN) and its components have been extensively studied in both healthy individuals and psychiatric patients. Several studies have investigated possible DMN alterations in specific mental conditions such as bipolar disorder (BD). In this review, we describe current evidence from resting-state functional magnetic resonance imaging studies with the aim to understand possible changes in the functioning of the DMN in BD. Overall, several types of analyses including seed-based and independent component have been conducted on heterogeneous groups of patients highlighting different results. Despite the differences, findings seem to indicate that BD is associated with alterations in both frontal and posterior DMN structures, mainly in the prefrontal, posterior cingulate and inferior parietal cortices. We conclude this review by suggesting possible future research directions.

The principle of pragmatism in clinical trials has been broadly recognised as a way to close the gap between research and practice. In this contribution, we argue that the conduct of pragmatic clinical trials in Europe may be hampered by poor implementation of current European Union's Clinical Trial Regulation No. 536/2014.

Maju et al. provided clarifications on important and controversial issues related to esketamine clinical trial data, in response to a vivid debate triggered by the marketing authorisation recently granted by this new medicine. In this commentary, we reply to their comments attempting to critically discuss the evidence base needed to obtain regulatory approval.

In March 2019, the US Food and Drug Administration (FDA) approved a nasal spray formulation of esketamine for the treatment of resistant depression in adults. Esketamine is the S-enantiomer of ketamine, an FDA-approved anaesthetic, known to cause dissociation and, occasionally, hallucinations. While ketamine has not been approved for depression in the USA or in any other country, it has been used off-label in cases of severe depression. This commentary critically reviewed the evidence on esketamine submitted to the FDA, aiming to draw implications for clinical practice, research and regulatory science.

Impairments in neuro and social cognition are considered core features of schizophrenia (SCZ) since they affect patients' functioning and contribute to poor socio-occupational outcomes. Therefore, the improvement of cognitive performances has become a primary goal in the care of patients with SCZ, especially in the first phases of the disease, as early interventions may favour better long-term outcomes. Cognitive remediation (CR) is a behavioural training aimed at improving cognitive functions with the goal of durability and generalisation in everyday life. Neuroimaging studies suggest that CR leads to neuroplasticity in chronic SCZ, whereas only a few studies tested the neural effects of CR in the early phase of the disease. Thus, in this review, we aimed at summarising CR-induced structural and functional brain changes in early SCZ. Existing evidence showed a protective effect of CR on grey matter volume in selected medial-temporal (i.e. hippocampus, parahippocampus and amygdala) and thalamic regions whereas functional changes affected mostly dorsolateral prefrontal and insular cortices both associated with improvements in cognitive performance and emotion regulation. Overall, CR in early SCZ appears to be associated with neural adaptations mostly allocated in prefrontal and limbic regions, however future longitudinal studies are needed to clarify whether the positive effects of cognitive training persist over time. It may also be interesting to investigate whether the application of CR in the early v. the late stage of the disease may lead to incremental benefits.

Since its development and theorisation in the 60s, attachment theory has greatly influenced both clinical and developmental psychology suggesting the existence of complex dynamics based on the relationship between an infant and its caregiver, that affects personality traits and interpersonal relationships in adulthood. Many studies have been conducted to explore the association between attachment styles and psychosocial functioning and mental health. By contrast, only a few studies have investigated the neurobiological underpinnings of attachment style, showing mixed results. Therefore, in this review, we described current evidence from structural and functional imaging studies with the final aim to disentangle the neural correlates of attachment style in healthy individuals. Overall, different attachment styles have been correlated with volumetric alterations mainly in the cingulate cortex, amygdala, hippocampus and anterior temporal pole. Consistently, functional imaging studies suggested patterns of activations in fronto-striatal-limbic circuits during the processing of social and attachment-related stimuli. Further studies are needed to clarify the neurobiological signature of attachment style, possibly taking into consideration a wide range of demographic, psychosocial and clinical factors that may mediate the associations between the style of attachment and brain systems (e.g., gender, personality traits, psychosocial functioning, early-life experience).

Hostility and related dimensions like anger, urgency, impulsivity and aggressiveness have been described in non-clinical populations and various serious mental illnesses including schizophrenia. Although representing a mental healthcare challenge, the investigation of such constructs is often limited by the presence of complex and multi-factorial causes and lack of agreement in their conceptualisation and measurement. In this review, we aim to clarify the anatomical basis of hostility-related dimensions in schizophrenia. Imaging studies suggest malfunctioning of a neural circuitry including amygdala, striatum, prefrontal cortex, anterior cingulate cortex, insula and hippocampus to modulate hostile thoughts and behaviours, at least in the subgroup of patients with schizophrenia who exhibit high levels of urgency, impulsivity and aggressiveness.

In individuals with coronary artery disease and concurrent depressive symptomatology, the evidence on the beneficial and harmful effects of antidepressants is very limited. Recently, a study was carried out to describe depressive symptoms and the treatments provided under real-world circumstances to cardiac patients who entered the Mayo Clinic cardiac rehabilitation program. Antidepressant use was associated with reductions in depressive symptoms, but also with poorer cardiovascular outcomes. In this commentary, the results of this study are discussed in view of their clinical implications for everyday clinical practice and for the production of knowledge.

A recent meta-analysis of antidepressant trials is the largest conducted to date. Although it claims to prove antidepressant effectiveness beyond dispute, the main outcome is response rates, which are derived from continuous data in a process that can inflate differences between groups. The standardised mean difference of 0.3 is in line with other meta-analyses that show small differences between antidepressants and placebo that are unlikely to be clinically significant. Other factors likely to exaggerate the effects are discussed, and evidence on associations between antidepressant effects and severity and outcomes of long-term treatment is considered. Clinicians need to have open discussions with patients about the limitations of antidepressant research, the lack of evidence that antidepressants correct a chemical imbalance or other brain abnormality, and the range of adverse effects and mental and physical alterations they can produce.

Cannabidiol (CBD) represents a new promising drug due to a wide spectrum of pharmacological actions. In order to relate CBD clinical efficacy to its pharmacological mechanisms of action, we performed a bibliographic search on PUBMED about all clinical studies investigating the use of CBD as a treatment of psychiatric symptoms. Findings to date suggest that (a) CBD may exert antipsychotic effects in schizophrenia mainly through facilitation of endocannabinoid signalling and cannabinoid receptor type 1 antagonism; (b) CBD administration may exhibit acute anxiolytic effects in patients with generalised social anxiety disorder through modification of cerebral blood flow in specific brain sites and serotonin 1A receptor agonism; (c) CBD may reduce withdrawal symptoms and cannabis/tobacco dependence through modulation of endocannabinoid, serotoninergic and glutamatergic systems; (d) the preclinical pro-cognitive effects of CBD still lack significant results in psychiatric disorders. In conclusion, current evidences suggest that CBD has the ability to reduce psychotic, anxiety and withdrawal symptoms by means of several hypothesised pharmacological properties. However, further studies should include larger randomised controlled samples and investigate the impact of CBD on biological measures in order to correlate CBD's clinical effects to potential modifications of neurotransmitters signalling and structural and functional cerebral changes.

A substantial proportion of people with mental health conditions do not adhere to prescribed pharmacological treatments. Poor adherence is probably one of the most critical elements contributing to relapse in people with schizophrenia and other severe mental disorders. In order to tackle this global issue, in November 2017 the Food and Drug Administration approved a tablet formulation of the atypical antipsychotic aripiprazole embedded with a novel digital adherence-assessment device. In this commentary, we critically appraised the potential beneficial and harmful consequences of this new digital formulation of aripiprazole, and we highlighted expected implications for clinical practice.

Research evidence guiding the identification of pragmatic and effective actions aimed at improving the selection, availability, affordability and rational prescribing of medicines for mental disorders is sparse and inconsistent. In order to boost the development of new research, in this commentary we suggest to organise and classify all the activities in this area under a common theoretical framework and nomenclature, adopting the term ‘public health psychopharmacology’. Public health psychopharmacology is proposed as a research discipline, based on contributions from the fields of regulatory science, health services research and implementation science. Implementing the term public health psychopharmacology may offer advantages, as the scientific community would be more focused on common goals and objectives, with, likely, an increasing body of research evidence of practical use.

Generalised anxiety disorder (GAD) is a common psychiatric illness characterised by selective morpho-functional brain alterations. The breath of neuroimaging studies investigating the neural basis of GAD is extensive; however, its pathophysiology is still largely unknown. Specifically for proton Magnetic Resonance Spectroscopy (¹H MRS) investigations, which have the aim of identifying differences in metabolite levels between conditions in key brain areas, often showed contrasting results. Indeed, there are selected ¹H MRS studies reporting deficits of key metabolites in GAD patients; however, collectively the literature remains mixed with respect to consistency of major findings. In this review, we evaluate published ¹H MRS studies on GAD with the final aim of providing a comprehensive overview of the extent of neurometabolic dysfunctions associated with GAD. Interestingly, the majority of the studies reviewed showed altered metabolite levels in the dorsolateral prefrontal cortex and hippocampus suggesting regional specificity. These results also provide evidence of the utility of ¹H MRS not only for elucidating the pathophysiology of neuropsychiatric diseases, but also for the identification of more beneficial and targeted pharmacological interventions. Additionally, future studies are warranted to overcome methodological differences observed across the studies.