Challenges in Internet Addiction Disorder: Is a Diagnosis Feasible or Not?

An important international discussion began because of some pioneer studies carried out by Young (a) on the internet addiction disorder (IAD). In the fifth and most recent version of the Diagnostic, and Statistical Manual of Mental Disorders (DSM) there is no mention of this disorder and among researchers there are basically two opposite positions. Those who are in favor of a specific diagnosis and those who are claiming the importance of specific criteria characterizing this behavior and the precise role it has in the patient's life. The aim of the present paper is to answer the question whether it is possible or not to formulate diagnoses of internet-related disorders. We revised literature on the history of diagnostic criteria, on neurocognitive evidence, on the topic debate and on IAD instrumental measures. We found that the disorder was not univocally defined and that the construct was somehow too broad and generic to be explicative for a diagnosis. Indeed, the models are borrowed from other addiction pathologies and they are often formulated before the development of internet as intended in current society. In conclusion, we think we need a more innovative, integrated and comprehensive model for an IAD diagnosis.

Transcranial magnetic stimulation of medial prefrontal cortex modulates implicit attitudes towards food.

The medial prefrontal cortex (mPFC) is known to be associated with food representation and monitoring of eating behaviour, but the neural mechanisms underlying attitudes towards food are still unclear. Transcranial magnetic stimulation (TMS) was used in combination with the implicit association test (IAT) to investigate the causal role of mPFC in controlling implicit food evaluation in healthy volunteers. Participants performed an IAT on tasty and tasteless food to test TMS interaction with food evaluation. Moreover, IATs assessing self-related concepts and attitude towards flowers and insects were carried out to control whether TMS could also affect self-representation or, more in general, the cognitive mechanisms required by the IAT. TMS was applied over mPFC; the left parietal cortex (lPA) was also stimulated as control site. Results revealed that mPFC-TMS selectively affected IAT on food, increasing implicit preference for tasty than tasteless food, only in a subgroup of participants who did not show extreme explicit evaluation for tasty and tasteless food. This demonstrates that mPFC has a critical causal role in monitoring food preference and highlights the relevance of considering individual differences in studying food representation and neural mechanisms associated with eating behaviour.