Total aphasia ( Global aphasia , Sensomotor aphasia )
Total aphasia is a simultaneous, severely expressed impairment of the motor and sensory components of speech. The syndrome is characterized by a lack of spontaneous and misunderstanding of addressed speech, disorder of reading and writing operations, which makes verbal contact with the patient impossible. Of the concomitant disorders, hemiplegia is observed. The affected area is established using cerebral MRI / CT, ultrasound of the cerebral arteries. In order to assess the patient’s speech and psychological status, testing is performed. Treatment includes pharmacotherapy, neurosurgical interventions, speech therapy, neurocorrection. In this article we will elaborate the Total aphasia symptoms classification.
General information
Total (global, sensorimotor) aphasia is the most severe form of aphatic disorder, in which expressive and receptive language skills are equally affected. The frequency of global aphasia is unknown, since more often diffuse speech impairment is of a transient nature and is observed only in the acute period of a cerebral catastrophe. In about a third of cases, total aphasia remains in the residual period of injury or illness. This leads to severe and long-term disability of patients, requires the involvement of significant rehabilitation resources.
The reasons
Total aphasia is the result of an extensive lesion of the dominant hemisphere, covering several areas of speech that are responsible for the production and understanding of speech. The centers of Broca, Wernicke (perisylvian region), insular lobe, parietal regions are involved in the pathological process in various combinations. Often, sensorimotor aphasia is caused by damage to the subcortical structures: the thalamus, basal nuclei, white matter of the brain. Such lesions can develop as a result of the following reasons:
- head trauma : severe brain contusion, open head injury , intracranial hematoma;
- cerebral strokes: cerebral infarctions (as a result of occlusion of the middle cerebral or internal carotid artery), hemorrhagic strokes ;
- brain tumors : with benign neoplasias, a differentiated form of aphasia develops first, then total; the rapid expansive growth of a malignant neoplasm leads early to the global disintegration of speech;
- degenerative neurological diseases : Pick’s disease, Landau-Kleffner syndrome , late stage Alzheimer’s dementia;
- encephalitis .
Transient global aphasia, when the patient loses speech function for a short time, may result from a transient ischemic attack , migraine attack, or epileptic seizure.
Pathogenesis
The mechanism of development of total aphasia depends on the area of the lesion. So, with the involvement of the perisylvian cortex (the area around the Sylvian groove separating the frontal and temporal lobes) and the parietal cortex adjacent to this area, oral-articulatory apraxia and acoustic agnosia develop . Pronunciation, understanding, repetition of oral and written utterances are impaired. The perisylvian region is supplied with blood from the basin of the middle cerebral artery, therefore, its occlusions or ruptures are most often the cause of total aphasia.
The defeat of the subcortical structures is closely related to the cortical speech centers. In the presence of subcortical pathological foci, speech activity is impaired by the type of pseudofrontal and pseudotemporal syndromes. In addition, total aphasia occurs if the lesion affects the white matter of any lobe of the brain: temporal, frontal, parietal.
Global aphasia is often observed in the first day after severe brain damage due to cerebral edema. After some time, as natural recovery and as a result of therapy, total aphasia can be transformed into expressive (motor) or receptive ( sensory ) aphasia . In some cases, the syndrome of total speech disintegration remains as the main one.
Classification
Total aphasia is divided into 2 types, depending on the preservation of speech functions:
- complete – an absolute lack of verbal capabilities: the patient is not able to speak and understand speech;
- partial – partly preserved may be the ability to understand the speech of others or pronounce individual sounds.
It was noticed that large in area, but small in extent, lesions (hemorrhages, ischemia) cause aphasia with partial preservation of understanding of the addressed speech. On the contrary, laterally located, anteroposteriorly elongated zones of damage determine the full form of total aphasia.
Symptoms of total aphasia
In the acute post-stroke or post-traumatic period, most aphatic disorders are global in nature. Patients have impaired both motor and sensory links of speech function. As a rule, in the first weeks after an acute cerebral accident, speech understanding gradually improves, and global aphasia is replaced by another form, more often by severe Broca’s aphasia . However, in some patients, the global disintegration of language function persists for a long time.
Despite the severity of the speech impairment, the language capabilities of individuals with global aphasia may vary. Some patients can pronounce some sounds and words, in particular, spontaneous answers “yes” and “no”, or automated series (counting, listing the days of the week, words of songs). These patients may have an emotionally charged speech embolus .
A similar situation is observed with the understanding of speech. Some patients recognize by ear and react to personally meaningful designations (names of loved ones, names of familiar places), while other topics of conversation remain incomprehensible. People with total aphasia can guess the facial expressions or tone of voice of the speaker, so they often seem to understand speech better than they actually do. Other patients with total aphasia are unable to utter a single sound and do not understand the addressed speech .
Reading, counting, writing ( alexia , acalculia , agraphia ) are grossly violated or completely impossible . Almost all patients have right-sided hemiplegia / hemiparesis, deep hemihyposthesia or hemianesthesia, hemianopsia are often detected . Thanks to the preservation of the right hemisphere, a person with total aphasia can express himself with the help of facial expressions, intonation, and gestures.
Complications
Extensive brain damage that disrupts speech potential can also impair other mental functions. In the presence of concomitant cognitive deficits, difficulties with attention, memory, and learning may arise. Without proper restorative treatment and rehabilitation, patients with total aphasia remain deeply disabled due to the complete impossibility of communication with the outside world, restrictions on movement and self-service. Such patients experience deep depression and often lack sufficient motivation to exercise.
Diagnostics
Examination of a patient with a total decay of speech skills begins with determining the cause and zone of cerebral lesion. Establishment of the form of aphasia becomes possible only after the end of the acute period of cerebral catastrophe. Doctors-neurologists and neurosurgeons, speech therapists, neuropsychologists participate in diagnostic consulting of patients . Minimum survey plan: Total aphasia symptoms classification
- Determination of the cause and focus of the lesion. Immediately after a brain accident, patients undergo non-contrast CT or MRI of the brain . For the detection of pathology of the cerebral and precerebral arteries, MR angiography or CT angiography is most informative . Ultrasound of the vessels is also used (ultrasound of the carotid and vertebral arteries, TCD of the cerebral arteries). With the help of these methods, foci of ischemia, hemorrhages, atrophy of the medulla are revealed.
- Consultation with an aphasiologist . In the case of total aphasia, the speech therapist states the lack of independent speech, understanding of commands and instructions, the ability to count, write, and read. Productive speech contact with the patient is impossible. Sometimes the preservation of automated speech, partial understanding of circulation, embolophrasia is noted.
- Consultation with a neuropsychologist . In the study of higher mental functions, attention is paid to the state of various types of gnosis, praxis, attention, memory. Batteries of cognitive tests are underway. The use of intact links in correctional work helps to speed up the process of restoration of speech and non-speech functions.
Treatment of total aphasia
Therapy and surgery
In the first hours of ischemic stroke, reperfusion therapy (intravenous or intra-arterial thrombolysis ) is most effective . To combat cerebral edema, diuretics, moderate hypothermia are used. During the treatment period, patients receive anticoagulants , antiplatelet agents, neuroprotectors, antioxidants, antihypertensive drugs.
According to the indications, surgical interventions are carried out: carotid endarterectomy , implantation of a carotid stent into the internal carotid artery, removal of cerebral neoplasias. Intracranial hemorrhages require craniotomy and surgical removal of the intracerebral hematoma , aspiration of the hematoma through the milling hole, and stereotaxic removal .
Physical rehabilitation
Physical rehabilitation methods are aimed at enhancing physical activity, the ability to self-service. Patients are recommended dosed physical activity: therapeutic exercises , mechanotherapy , ergotherapy. With concomitant dysphagia, Vocastim neuromuscular stimulation sessions are performed . In case of paresis, it is advisable to prescribe procedures for electrophoresis , myostimulation , magnetotherapy, darsonvalization .
Speech therapy correction
In speech restoration classes, priority is given to improving the perception of addressed speech. For this, non-speech auditory gnosis, acoustic attention and control are first activated. Then they move on to the differentiated perception of speech sounds and their pronunciation. At the same time, they rely on tactile sensations, visual perception, and resort to gustatory and olfactory stimulation.
In the speech rehabilitation of persons with total aphasia, a special role is played by the use of various mobile applications, means and methods of alternative speech communication, sign speech. Despite the fact that speech therapy is not always effective in the syndrome of total aphasia, it can significantly expand communication skills, improve the well-being of patients, and reduce the level of depression.