Skip to main content

Neurological Functional Explorations

Neurological Functional Explorations welcome patients (children and adults) ( EEG ) , electromyogram ( EMG ), evoked potentials and repetitive transcranial magnetic stimulation (rTMS) examinations .

Specialized consultations for epilepsy are also offered.

  • Crew

  • Activities

    Activities and collaborations

    The neurological functional explorations department has a significant intra-hospital cross-functional activity:

    • Performing EEGs for all hospital departments, particularly in neurology, medical and surgical resuscitation, pediatrics, neonatology, geriatrics, emergencies, etc.
    • Intraoperative neurophysiological monitoring in pediatric orthopedic surgery and neurosurgery (interventions on scoliosis, brain tumours, etc.)

    The service works in close collaboration with the Neurology service for the care of epileptic patients. Consultations are provided by 2 neurologist practitioners from the Neurological Functional Explorations department but also by practitioners from the neurology .


    The service represents a resource activity at the level of the department and the region

    A number of electroencephalograms performed in other hospitals in the region, and in particular the majority of EEGs , are sent to us for remote interpretation via a dedicated platform.

    In addition, activities that are more confidential because they are very specialized are carried out only at the CHU de Caen (single fiber, oculography in parkinsonian syndromes +, rTMS in functional paralysis, EMG of the perineum, etc.).



    The team organizes quarterly meetings by videoconference, accessible to neurologists in the region and participates in inter-regional meetings with the University Hospitals of Rouen, Amiens and Lille to deal with difficult cases.

    Finally, it ensures the training of health professionals, the dissemination of good practices in terms of neurophysiological explorations and communication around epilepsy.


    For epilepsy consultations, appointments are offered upon written request from the patient's general practitioner and/or specialist. Neurophysiological explorations, which are essential for monitoring this pathology, are carried out in the Neurological Functional Explorations department for routine electroencephalograms, and in the Sleep Unit for long-term EEGs They are carried out by paramedical personnel specifically trained in this pathology.

    A specific Epilepsy-Work consultation is offered in collaboration with Professor Bénédicte Clin-Godard Occupational Health and Occupational Pathology department .

  • Your questions

    What is an electroencephalogram?

    Electroencephalography is a cerebral exploration method that measures the electrical activity of neurons, and its variations over time, through electrodes placed on the scalp.

    It allows the study of the functioning of the brain in healthy people (for example cerebral maturation in babies, or the different stages of sleep) , but also the diagnosis of certain diseases which modify cerebral electrical activity, in particular epilepsy and vigilance disorders or comas.

    It is a completely safe and painless "non-invasive" technique, most often requiring no preparation other than clean, dry hair, and which can be performed in all circumstances, on an outpatient basis, in intensive care, or at the patient's bedside, in both children and adults. Prior sleep deprivation is sometimes requested.

    For external examinations, except in the case of very small children or patients with an intellectual disability, a minimum of cooperation from the patient is desirable for a quality examination ( stay calm, open and close your eyes, blow, etc.).

    The examination generally lasts less than 30 minutes but it is possible to make recordings of longer duration, with sleep for example (during a nap or overnight) or over several consecutive days for exploration certain illnesses and epilepsies. These last examinations are carried out in the Sleep Unit.

    What is an electroneuromyogram (ENMG)?

    This is an examination of the nerves and muscles carried out by a neurologist specialized in this technique:

    The examination is carried out in two parts:

    • A first part, called stimulo-detection, studies the functioning of the nerves. An electrical stimulator placed on the skin near the nerve will activate the nerve, and trigger a muscle contraction or a sensory potential, thus making it possible to measure the conduction speed of the nerve and to highlight a possible loss in nerve fibers or damage. of the sheath that surrounds them (myelin). We can thus confirm the diagnosis of disease of the peripheral nerves (peripheral neuropathy) or of the motoneuron (cell located in the spinal cord which is at the origin of the motor nerve). Repetitive stimulation can also highlight a transmission disorder between nerve and muscle (as in myasthenia).
    • A second part, the electromyogram, is performed using a needle electrode that is pricked into the muscle: the activity of the muscle fibers is thus studied at rest and then during effort, in order to study the type recruitment of muscle fibers to effort, which makes it possible to direct towards a specific pathology of the muscle fibers (we then speak of myopathy) or towards a disease of the peripheral nerves or motor neurons.

    What is an evoked potential test?

    Evoked potentials are changes in brain electrical activity that can be recorded by the electroencephalogram.

    In clinical practice, these modifications are controlled, provoked, according to the sensory modality that one seeks to evaluate. Whatever the modality explored, the technique requires the recording of a consecutive series of responses, the average of which will present characteristics of amplitude (size) and latency (time to onset) that can be compared between normal and pathological situations.

    The modalities commonly explored in the service are the evoked, somatosensory and motor potentials. These examinations have a major interest in the exploration of spinal and peripheral neurological pathologies, can have an important prognostic value in the management of comatose patients in intensive care. This technique is also used in the department for perioperative monitoring of spine surgery.

    What is epilepsy?

    Epilepsy is a common disease that affects approximately 650,000 people in France, from early childhood to old age. It is a chronic neurological condition defined by the repetition of transient clinical phenomena called “epileptic seizures”. An epileptic seizure is a disorder of short duration resulting from an excessive and simultaneous electric discharge of a group of neurons of the cerebral cortex and its possible propagation.

    There are many different forms of seizures (convulsive seizures, absences, etc.) and therefore epileptic diseases. The causes of epilepsy are very numerous and varied (vascular or tumoral lesions, head trauma, malformations, genetic abnormalities, etc.). Having an epileptic seizure does not mean “being epileptic”, because it can be a single seizure, spontaneous or linked to an acute brain injury that will not recur. The level of seizure-related disability varies greatly depending on the severity of the disease and its impact on daily life.

    Diagnosis of the disease itself is based on observation of seizures and electroencephalogram ( see above). Instead, imaging tests like brain MRI aim to identify the cause of epilepsy.

    There is no medical treatment to cure the disease (only surgery can truly cure some forms of epilepsy), but many drugs are now available that can control seizures.