Cognitive Abilities in Brain Damaged Patients (Cog)

The presence of damage to the central and / or peripheral nervous system resulting from pathologies of a different nature (such as multiple sclerosis, Parkinson's disease, dementia, cranial trauma, stroke, epilepsy or other neurological syndromes) is commonly a cause of physical and mental disability. The presence of memory or language cognitive deficits is often evident at a first clinical examination. However, difficulties in cognitive areas such as decision-making, social and emotional cognition or particular forms of learning may be less evident, while exerting a strong impact on the quality of life of patients. The main purpose of this proposal is to investigate cognitive abilities in patients with neurological damage, through a series of specific tasks. In addition, the contribution of specific brain areas to the cognitive tasks will be assessed by direct modulation of brain activity. This modulation will be achieved by using non-invasive brain stimulation techniques such as Transcranial Magnetic Stimulation (TMS) and Direct Transcranial Electric Stimulation (tDCS).

The presence of damage to the central and / or peripheral nervous system resulting from pathologies of a different nature (such as multiple sclerosis, Parkinson's disease, dementia, cranial trauma, stroke, epilepsy or other neurological syndromes) is commonly a cause of physical and mental disability. The presence of memory or language cognitive deficits is often evident at a first clinical examination. However, difficulties in cognitive areas such as decision-making, social and emotional cognition or particular forms of learning may be less evident, while exerting a strong impact on the quality of life of patients. The main purpose of this proposal is to investigate cognitive abilities in patients with neurological damage, through a series of specific tasks. To this end, a series of tests and questionnaires will be used, described in detail below, to evaluate various cognitive functions, including decision-making, problem-solving, learning, memory, executive, social and emotional cognition. In addition, the contribution of specific brain areas to the cognitive tasks will be assessed by direct modulation of brain activity. This modulation will be achieved by using non-invasive brain stimulation techniques such as Transcranial Magnetic Stimulation (TMS) and Direct Transcranial Electric Stimulation (tDCS). TMS, in particular, is a non-invasive neuronal stimulation of surface areas of the brain that since its inception has been frequently used in neurology as a diagnostic and research tool. TMS uses magnetic fields to induce electrical currents that facilitate or inhibit cortical activity. TDCS consists in the application of weak electrical currents to generate an electric field that can modulate neural activity in an excitatory or inhibitory manner. TMS and tDCS can be used in the experimental field to modulate cortical activity and modify performance during cognitive tasks. An important mechanism responsible for clinical, cognitive and functional recovery after neurological damage of different types is synaptic plasticity. Nervous tissue has the ability to permanently enhance or de-energize inter-neuronal transmission at synaptic level. By increasing the efficiency of synaptic transmission, through a phenomenon known as long-term potentiation (LTP), it is possible to compensate the loss of synaptic pulses on survived neurons due to brain damage and restore their function. LTP is also capable of guiding the formation of new brain circuits (structural plasticity), with compensatory and adaptive function . Indeed, neurotransmitters, in addition to their bioelectric conduction activity, also act on neurotrophic factors. Aim The aim of this study is to evaluate cognitive abilities in healthy subjects and in patients with neurological injury of various kinds (such as multiple sclerosis, Parkinson's disease, dementia, cranial trauma, stroke, epilepsy or other neurological syndromes) as well as to deepen the contribution of specific brain areas in carrying out these cognitive tasks. This will be made possible thanks to the specific skills of a multidisciplinary team of neurologists and physiatrists, health professionals such as physiotherapists, occupational therapists, psychologists, speech therapists, and the support of a biomedical engineer. These professional figures are already available at the UUOOCC of Neurology Neurosurgery and Neurosurgery directed by the proposer.

Associative learning tasks will be inspired by those previously used in literature during which subjects should learn a series of stimulus-outcome associations (pavlovian learning) or response-outcome (instrumental learning).

Neurological deficits can affect the ability to learn from past mistakes and make decisions for the future. To observe the decision-making mechanisms and to analyze the ability to choose, a series of more or less risky economic choices will be presented, which can result in both a payout or a loss. Initially participants receive a sum of virtual money with the instruction to maximize the payout. An unaltered decision skill should have the ability to make the least risky choice and involve more long-term wins.

To evaluate social and emotional cognition, a series of tests will be used to quantify both the ability to empathize and understand the emotions of others, and the ability to intrepret their thoughts and intentions. A classical test involves the presentation of facial expressions and is asked to choose which word best describes what the person in the image is thinking or trying.

Inclusion criteria: Males or females aged between 18 and 80; Presence of brain damage resulting from: Multiple Sclerosis, Parkinson Disease, Dementia, Cranial Trauma, Neurosurgical Intervention, Ictus, Epilepsy or Other Neurological Syndromes (for the experimental group only); Absence of neurological disorders (for the control group only); be able to follow the protocol's directions throughout the study; Female subjects undertake not to schedule a pregnancy for the duration of the study; Patients should be able to follow protocol guidelines throughout the study; Patients should be able to understand the aims and risks of the study; Signature of informed consent, approved by our Ethics Committee. Exclusion criteria: Incapability even partial to understand and want; Patients with other pathologies which, according to the opinion of the scientific manager, prevent the recruitment; When using non-invasive brain stimulation techniques or subjects should not submit any of their own contraindications (for further details, see the "Methods" and "Stimulation Evaluation Questionnaire" attached to this proposal); Pregnancy, breastfeeding, and delivery not less than three months before the start of the study.

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