Bárbara Ferreira

Tourette's syndrome and associated disorders: a systematic review

OBJECTIVE To compile data on Tourettes syndrome (TS), tics and associated disorders. METHODS A systematic review of the literature was conducted using the 5S levels of organization of healthcare research evidence (systems, summaries, synopses, syntheses, studies), based on the model described by Haynes. The search keywords were Tourette, tics and comorbidity, which were cross-referenced. Studies provided by publishers and articles being processed on July 31, 2013, were also included. RESULTS Of all studies retrieved during the search, 64 were selected because they analyzed the epidemiology, clinical features and etiopathogenesis of TS and its comorbidities. TS is classified as a hyperkinetic movement disorder, and at least 90% of the patients have neuropsychiatric comorbidities, of which attention deficit hyperactivity and obsessive-compulsive disorders are the most common. The syndrome is clinically heterogeneous and has been associated with a dysfunction of cortico-striatal-thalamic-cortical circuits involving various neurotransmitters. Although its genetic etiology has been widely studied, other factors may be important to understand this syndrome and its associated disorders. CONCLUSIONS TS is a neurodevelopmental disorder that results from the impact of stress factors on a vulnerable biological substrate during the critical periods of neurodevelopment. The study of TS and its comorbidities may contribute, at different levels, to the understanding of several neuropsychiatric disorders of clinical and therapeutic relevance.

Cognition and meaning

http://dx.doi.org/10.1016/j.mehy.2016.06.019 0306-9877/ 2016 Elsevier Ltd. All rights reserved. Tomoyuki Kawada queried our paper about meaning, stating that ‘‘cognition of the meaning is the integration of mind expression in humans, and biological localization of the words in the brain hemisphere was a fraction of human cognition” [1]. In fact, words (Saussurean signifier) and their relationship (Saussurean value or sense) may be computed by a small part of the brain (Broca and Wernicke areas, generally in the left hemisphere), like a computer. However, words have meaning (Saussurean signified), which we localize in the rest of the brain, namely the corresponding areas in the right hemisphere [2]. These proposals have implications for the Philosophy of Mind and help to explain schizophrenia, which is also pathology of meaning. ‘Meaning’ is a paradoxical word, since we can ask ‘‘what is the meaning of meaning”. Furthermore, it is a pervasive concept. We can apply it not only to words but also to life. We think that Kawada uses the concept in this latter sense. He quoted studies on happiness and invokes the French philosopher Henri Bergson to substantiate his statements. In fact, Bergson [3] distinguished two different ways of knowing. One of them evolved from construction (of nests and tools) in non-human animals to manufacturing signs (and words) and dealing with them, leading to human intelligence. The other way of knowing evolved from animal instinct to human intuition. Intelligence, resulting from thinking while dealing with words and signs, is radically and greatly developed in humans. According to Bergson [3], it also transforms human instinct into intuition. However, instinct and intuition are linked to life in its totality and correspond to another but decisive way of knowing. They belong to temporal duration, and may proceed by synchronization with other living beings, leading to a sensation of fulfillment and happiness [4]. Thus, in spite of the special connotation related to words, we agree that meaning, which is acknowledged by intuition, is a general concept. In spite of some brain fractions processing words (the ‘‘brain computer”), meaning is processed by the whole brain, body and life in general.