Intellectual disability

Introduction to intelligent obstacles Disturbance of intelligence is a group of clinical syndromes that can have at least three impairments of memory, cognition (generalization, calculation, judgment, etc.), language, visual spatial function, and personality, often caused by neurological diseases, mental illnesses, and Caused by physical illness. The main symptoms include: 1 memory disorder; 2 thinking and judgment disorder; 3 personality change; 4 affective disorder, here mainly describes the general clinical manifestations of congenital intelligence disorder (mental retardation), memory disorder (amnesia syndrome) and dementia . basic knowledge The proportion of illness: 0.003% Susceptible people: no specific population Mode of infection: non-infectious Complications: dementia

Cause of intellectual disorder

(1) Causes of the disease

The causes of intellectual disabilities can be divided into two categories:

1 congenital mental retardation: such as mental retardation;

2 Acquired sexual intelligence disorders: such as acute brain trauma, metabolic disorders, poisoning diseases can cause temporary mental retardation, dementia is the most common acquired progressive cognitive dysfunction.

(two) pathogenesis

1. Intelligent hypoplasia (oligophrenia)

Also known as mental retardation, this is a state of mental development hindered or incomplete, mostly caused by genetic and environmental factors, environmental factors are the mother's pregnancy infection, birth injury and postnatal brain hypoxia, infection, etc. Genetic factors include genetic metabolic defects, chromosomal abnormalities and dominant genes.

2. Memory disorders

Memory is a more complicated problem, because the memory process includes information reception, encoding-storage and decoding-retrieval, and the most likely structures involved in memory trace formation are the cerebellum, hippocampus, amygdala and cerebral cortex.

(1) According to the time course of memory, memory can be divided into 4 categories:

(2) According to the content of memory, it can also be divided into four categories:

1 Image memory - the memory of the content of the object.

2 Logical memory - about the meaning, nature, laws of change, etc. of things, or memories of abstract concepts and judgmental reasoning.

3 Emotional Memory - A memory that involves certain emotional experiences and emotional changes as content.

4 sports memory - skills and skills in the operation and memory or habitual movements and other aspects of memory.

(3) There are many forms of clinical memory impairment:

1 Different degrees of changes in memory function: hypermnesia; hypomnesia.

2 memory blank or amnesia: amnesia is only a form of memory dysfunction, and its specific manifestations are of various types: antero-grade amnesia; retrograde amnesia; progressive Progressive amnesia; systematic elementary amnesia; selective amnesia; temporary amnesia; transient amnesia.

Some forgetting tends to be obstacles in the acquisition stage. Some forgetting is mainly because the input information cannot be stored and consolidated normally, and some forgetting is a comprehensive obstacle to the learning and memory process, but it is usually a barrier to the recall (reproduction) process and comprehensive. Damaged.

(4) The pathology of memory is studied in two aspects:

1 organic amnesia: is a memory disorder secondary to brain lesions, which belongs to the scope of neuropsychology.

2 affective amnesia: At this time, the memory disorder depends on the nature and organization of the material in a person's life experience. The brain does not have any lesions and belongs to the scope of psychopathology.

Here we mainly discuss various organic amnesia.

Dementia

Dementia is a persistent acquired mental retardation syndrome that must have barriers in the spiritual realm of speech, memory, visual spatial function, mood or personality and cognition (abstract thinking, calculation, judgment, and executive ability, etc.) Consciousness is not turbid, and emotional decline, social behavior or motivational decline is often associated with cognitive impairment, and occasionally earlier than cognitive impairment.

The incidence of dementia accounts for about 4.5% of the population. In the elderly with dementia, the statistics of Alzheimer's disease (AD) in Europe and the United States, referred to as senile dementia, account for 50%; multi-infarct dementia (also It refers to vascular dementia (12% to 20%), and the remaining dementia accounts for 15% to 20%.

According to the different parts of the brain, dementia syndrome can be divided into cortical dementia, subcortical dementia, cortical and subcortical mixed dementia and other types of dementia syndrome.

Intelligent obstacle prevention

Let your child exercise more brain exercise every day and learn more about some problems.

Intellectual disorder complications Complications dementia

There are generally no other complications.

Symptoms of intelligent disorder Common symptoms Dementia progressive dementia consciousness loss attention disorder Social sensitivity disorder Cortical amnesia Anxiety adaptation disorder Autism Fragile X syndrome convulsion

Intelligence (or intelligence) generally refers to the ability to accept and use knowledge. It involves a series of processes such as feeling, memory, judgment, analysis, etc. The definition of intelligence is different because of the different researchers. The definition is : "The ability to learn, the ability to apply the acquired knowledge and skills to the environment."

1. Intelligent insufficiency (amentia)

Or mental retardation, characterized by lower than normal levels of intelligence (such as cognition, language, exercise, and social skills), manifested as obstacles in learning and social adaptation, and mental retardation can occur alone or with Other mental or physical illnesses.

According to the degree of mental retardation, intelligent developmental insufficiency can be divided into:

(1) Mild intelligence: IQ is 50 to 69 (the intellectual age of adults is equivalent to 9 to 12 years old).

(2) Moderate intelligence: IQ is 35 to 49 (the intellectual age of adults is equivalent to 6 to 9 years old).

(3) Severe intelligence: IQ is 20 to 34 (the intellectual age of adults is equivalent to 3 to 6 years old).

(4) Extremely low intelligence: IQ is less than 20 (the intellectual age of adults is less than 3 years old).

Intelligent hypoplasia caused by hereditary metabolic defects, such as phenylketonuria (phenylketonuria), is an abnormal amino acid metabolism, is autosomal recessive, clinical manifestations of mental retardation and seizures, but limb paralysis and deformity are rare.

Chromosomal diseases caused by chromosomal abnormalities such as congenital premature, also known as 21-trisomy syndrome, Down syndrome and distracting tongue, clinical manifestations of intelligent inferiority and special physical features (such as a unique face, through the palm, large Cracked tongue), low muscle tone, delayed development, and congenital heart and gastrointestinal defects.

Fragile-X syndrome belongs to a heritable point defect on the human X chromosome (Xq27-28), which is characterized by a non-staining gap in the middle of cell division, which makes the chromosome extremely easy to break. Severe mental retardation, male patients with features such as large testicles, large ears, characteristic face, convulsions and autism, cytogenetics and cyto-molecular methods help to diagnose male patients and female carriers.

2. Amnesia

(1) Several different manifestations of organic forgetting:

1 anterograde amnesia: that is, can not recall the events experienced in the period after the disease occurs, the time of forgetting and the disease start at the same time, the ability to turn short-term memory into long-term memory, antegrade Forgotten patients who are common in concussions and brain contusions, patients can not recall the things experienced during the period of injury, such as how he was injured, the rescue process and hospitalization, and the patients with bilateral hippocampal resection have antegrade amnesia. However, the original memory is not affected, and the pathological changes of the papillary body, the anterior nucleus of the thalamus and the medial nucleus of the dorsal nucleus and the sacral sac can also occur. Mori reports that a patient with left anterior thalamic infarction has an antegrade Forgotten, Hodges reported that two patients had obvious anterograde amnesia after corpus callosum resection of the third ventricle cyst. CT and MRI showed damage to the sacral column. Duykaerts reported anterograde amnesia in one patient with Hodgkin's disease. Retrograde amnesia, pathology showed that neurons on both sides of the hippocampus and amygdala almost disappeared.

2 retrograde amnesia (retrograde amnesia): that is, can not recall a certain stage of the disease before the occurrence of a long-term memory disorder, the patient can not recall where he was before the injury, what is being done, the forgetting may be complete or Partial, short, several seconds, many years, mostly involved in a shorter period of time, retrograde amnesia is more common after cerebral ischemic attack, cranial trauma with conscious disturbance, and recovery of heartbeat resuscitation It can be seen in senile psychosis, CO poisoning and severe trauma. The thalamus is the relay station for all feelings entering the brain. It is also an important hub of memory and thinking nerve trajectory. The thalamic lesions may have retrograde forgetting. Korsakoff psychotic lesions mainly involve the thalamus. The dorsal nucleus and nipple body often show prominent memory disorders, and the retrograde amnesia of brain extensive lesions in craniocerebral trauma is directly proportional to the extent of lesion involvement.

3 progressive amnesia: With the aggravation of brain diseases, memory disorders are also progressively worsening, mainly long-term memory defects, recognition and recall are seriously affected, compared with serious progressive forgetting and past memories The patient's adaptation to real life is still good, mainly seen in senile dementia, in addition to forgetting, accompanied by increasing dementia and apathy.

4 Posterior amnesia: refers to the recovery of consciousness after the occurrence of the disease (such as after brain trauma, CO poisoning wakes up), the memory is still good, after a period of time there is obvious forgetting.

(2) Clinical type of amnesia:

1-axis amnesia: Forgotten due to damage to the ascending reticular system, the up-regulated reticular system that regulates alertness plays a major role in the memory mechanism, regardless of the cause of coma, coma when the uplink network The system stops functioning and deprives all memory activities. The patient cannot retain any recalls of this period. These memory disorders include: amnesia during a systemic episode of epilepsy and a period of time after seizure; amnesia caused by electroshock; Amnesia for amnesia.

Axonal amnesia caused by disease of the limbic system: brain lesions disrupting certain structures at the base of the brain located on the inner side of the cerebral hemisphere in a bilateral manner, leading to this very special syndrome, characterized by patients with isolated memory impairment Other advanced features and neurological examinations are normal.

A. Clinical manifestations:

a. The serious gradual forgetting, that is, antegrade forgetting, leads to major obstacles to memory, and learning new materials is almost completely powerless.

b. The memories of past events are poor, that is, a certain degree of retrograde amnesia. In the axial amnesia syndrome, memories often have serious obstacles.

c. Patients are well adapted to real life compared to severe gradual forgetting and recollection difficulties.

B. The axial amnesia syndrome caused by different causes has different characteristics:

a. Malnutrition encephalopathy: Chronic alcoholism is the most common cause of axial amnesia. Chronic alcoholism causes B vitamin deficiency indirectly, especially in the absence of B1. At this time, memory impairment is accompanied by confusion. Increased muscle tone, eye movement paralysis and cerebellar syndrome.

b. amnestic encephalitis: refers to the observation of universal amnesia syndrome with severe and rapid gradual forgetting and recall difficulties in some encephalitis processes. At this time, the characteristics of memory disorders are: serious in all fields. Obstacles to information preservation; impossible recalls; serious obstacles in the timing of new events; tend to use stereotyped statements, lack of reasoning; fictional rare and poor content.

The etiology of this type of encephalitis is not single. These amnesia syndromes are seen in typhoid fever, mumps encephalitis, herpes zoster encephalitis, even after coccidiomenitis or tuberculous meningoencephalitis, most common in Herpetic necrotizing encephalitis, necrotic lesions are located in the temporal cortex, subcortical white matter, hippocampal formation and amygdala.

c. Tumors at the base of the brain: Some tumors at the base of the brain, especially the tumors in and around the third ventricle, are common and severe.

d. Cerebrovascular disease: bilateral infarction of the hippocampus: caused by occlusion of the posterior small artery of the posterior communicating artery, choroidal artery and posterior cerebral artery. At this time, memory impairment is often submerged in the symptoms of dementia, which is completely unavailable. New things, bilateral thalamic infarction: At this time, the patient is lifeless, active activity is reduced, exercise initiation is reduced, and attention is paid to, and the latter is accompanied by mental sensory impairment.

e. Craniocerebral trauma: Craniocerebral trauma leads to memory impairment, caused by loss of consciousness. The amnesia syndrome is extremely diverse. Its characteristics and types depend on the extent of brain lesions. Fictional syndrome is a common symptom in traumatic sequelae. It is especially common in imaginative subjects involving the environment when an accident occurs.

2 Cortical amnesia: This type of amnesia is characterized by recall, application and learning of certain forms of cognitive difficulties that can be classified as:

A. Focal amnesia caused by dominant hemispheres of the posterior frontal lobe: This type of speech disorder is a focal lexical amnesia caused by the destruction of word storage. The main feature is the difficulty of finding words, which can be attributed to aphasia. Under the forgetting program, in such focal amnesia caused by lesions in the speech area, immediate memory ability is often lower than normal.

B. Focal amnesia caused by non-dominant hemisphere frontal lesions: Non-dominant hemispheric lesions, whether extensive or localized, cause focal amnesia as acquired cognitive impairment.

C. Frontal amnesia: The patient's understanding of the situation is very poor, and the obstacles of the joint strategy lead to incomplete or inappropriate cognitive and recall functions. The learning ability of patients with frontal lobe lesions is poor and irregular.

3 Complete amnesia: diffuse lesions in the brain cause intelligent defects and loss of memory in different degrees, so that the cognitive capacity of patients not only stops increasing, but also gradually shrinks and deteriorates. Such diffuse lesions are seen in infections. Sexual, nutritional deficiencies and severe sequelae of traumatic encephalopathy, also seen in arteriosclerosis, degenerative, premature and senile dementia, which cause complete amnesia; memory disorders actually involve all stages of life and involve patients The activities acquired the day after tomorrow, including speech, gestures and all intellectual skills.

4 transient organic amnesia: transient amnesia is common in metabolic encephalopathy, acute poisoning, cerebral hypoxia, but also in the following two situations: forgetting during systemic seizures and forgetting after seizures; a series of Forgotten observed after electroshock; a series of oblivions observed after electroshock.

A. Forgotten episodes: amnestic seizures or transient complete forgetting, which occurs suddenly in patients without any special past medical history. In the course of an acute episode that usually lasts for several hours, the patient's forgetting surprises the surrounding people. It seems that living in a constant reality, and quickly forgetting what he has just done and said, this antegrade forgetting is manifested in the problem that patients often ask in a rigid way, retrograde forgotten performance For the patient to forget the events that occurred in the hours or even days before the attack.

Transient vascular occlusion, epilepsy, migraine, hypoglycemia, etc. in the terminal distribution of the posterior cerebral artery can be the cause of amnestic seizures. Different causes of transient damage to the limbic system, especially the hippocampal formation, can lead to forgetting. attack.

B. Traumatic amnesia: Most craniocerebral trauma with coma leads to memory impairment. Memory difficulties involve not only the memory difficulties experienced during a period of trauma (antegrade amnesia), but also the trauma of patients who are completely normal before trauma. The difficulty of recalling during a period of time (retrograde forgetting) constitutes a blank for all traumatic forgetting.

Dementia

The relevant content of dementia has a separate narrative. Here is only a brief description of its classification, the clinical type of dementia syndrome:

(1) Cortical dementia:

1 Alzheimer's disease.

2 prefrontal degenerative disease (Pick disease).

(2) Subcortical dementia:

1 extrapyramidal syndrome (Parkinson's disease, Huntington's disease, etc.).

2 hydrocephalus (such as normal intracranial pressure hydrocephalus).

3 depression (pseudo-dementia).

4 white matter lesions (multiple infarction, human immunodeficiency virus disease).

5 cerebral vascular dementia (cavity state, multi-infarction type, etc.).

(3) Cortical and subcortical mixed dementia:

1 multi-infarct infarct dementia.

2 infectious dementia (viral dementia, etc.).

(4) Other dementia syndrome (after brain trauma and cerebral hypoxia, etc.): A considerable part of dementia is still refractory due to the fact that the cause is not fully understood. For example, AD dementia is currently being studied from molecular diseases. Etiology, molecular genetics, and molecular biology for the etiology of AD. Molecular pathology studies have found that neurofibrillary tangles (NFT), senile plaques, brain atrophy, and cholinergic nerves of the Meynert basal ganglia can be found in the brains of AD patients. Loss of the yuan and so on.

The cause of Pick's disease is also unclear. It may be a dominant genetic disease with multiple genes. The pathology of Pick's disease is completely different from Alzheimer's disease, with localized cortical atrophy. It is found that Pico cells and Pico bodies, the disease begins in middle-aged progressive dementia, which is a slow personality change and social decline in the early stage, leading to the decline of intelligence, memory and language function, and can be expressed as indifference in the late stage. Fast, occasionally extrapyramidal symptoms.

Clinically treatable dementia is a brain disease with a clear cause of onset, and it is not a neurological degenerative disease such as metabolism caused by systemic diseases, poisoning and brain trauma.

Smart barrier inspection

Select the necessary selective tests based on the likely cause.

Laboratory inspection

1. Blood routine, blood biochemistry, electrolyte attention to the specific changes in the diagnostic value of the primary disease.

2. Blood sugar, immune items, cerebrospinal fluid examination, if abnormal, there is a differential diagnosis.

Hematological examination is essential for determining dementia with endocrine diseases and liver and kidney failure. Hypothyroidism is a reversible cause of dementia. When measuring serum vitamin B12 levels, vitamin B12 deficiency can be found. But there can be no anemia.

Neurosyphilis is extremely rare, but it is also a reversible cause, so serological tests for syphilis must be mandatory.

The concentration of the drug in the blood can be detected for poisoning.

If clinical presentation suggests evidence of vasculitis or arthritis, erythrocyte sedimentation rate and screening for connective tissue disease (eg, antinuclear antibodies and rheumatoid factor) are required.

For any young person with dementia, consideration should be given to the determination of human immunodeficiency virus titer, and if there is a manifestation of dyskinesia, ceruloplasmin should be measured.

Auxiliary inspection

The following items are abnormal and have a differential diagnosis.

1. CT, MRI examination.

2. EEG is helpful in identifying Creutzfeldt-Jakob disease, which has the characteristics of periodic discharge.

3. Skull base film, fundus examination.

4. Single-photon emission computed tomography (SPECT) functional brain imaging may also be helpful in diagnosis.

Intelligent obstacle diagnosis

Diagnostic criteria

Evaluating the patient's intelligence state is an essential part of the neurological examination. It includes the evaluation of consciousness, demeanor, behavior, emotion, content and coherence of thinking, feeling and intellectual potential.

Traditional smart state checks include:

1 General information: such as "Where were you born? What is the name of the mother?"

2 orientation function: such as "Where is this? Today is the number? What time is it?"

3 Concentration: Adopt the order reversal method, such as starting from "December" and telling the month of the year.

4 calculation: If you do some simple arithmetic, conversion, 110 consecutively minus 7.

5 Reasoning judgment and memory: If you identify 3 objects, then ask the patient to repeat their names, or let the patient listen to a story. After a few minutes, ask the patient to try to repeat, the most important of which may be the orientation of time, the reverse of the sequence. And memories of paragraph sentences.

In addition, when checking the intelligence state, it is necessary to do some high-level intelligence function detection, including language disorders (speech difficulty); structural disability; left and right orientation obstacles; unable to complete complex instructions, etc., especially It is difficult to be asked to do the midline crossover action, such as touching the left ear with the right finger; thinking activity without imagination (ie, intentional misuse; tell the patient, "If you have a box of matches, how to draw it" and ask him Demonstrate with action; ignore on one side; or not notice double stimuli, which are often accompanied by more limited brain lesions, but may also be seen in patients with delirium or dementia.

Differential diagnosis

The differential diagnosis of dementia requires an accurate medical history, neurological examination and physical examination.

In Alzheimer's disease, the typical symptoms are insidious onset. In other aspects of health, the course progresses slowly, but the disease develops relentlessly. On the contrary, patients with vascular dementia may have sudden onset of memory loss in their medical history. A clear history of stroke, or a manifestation of hypertension and heart disease, patients with a history of alcoholism should be highly suspected of the possibility of Korsakov's mental illness.

In addition to extrapyramidal symptoms such as rigidity, slow movements, posture changes, and some primitive reflexes (such as pout reflexes), physical examination of patients with Alzheimer's disease is generally normal. Conversely, vascular dementia syndrome can include Mild hemiplegia or other symptoms of the focal nervous system.

The diagnosis of dementia syndrome must take three steps: Step 1, first to determine clinically whether the patient has dementia, use the Folstein Short Mental State Examination (MMSE) or the revised Hasegawa Intelligence Scale to measure intelligence and screen, Step 2, to determine the brain lesions of dementia, a series of examinations, such as EEG, EEG topography, single photon emission computed tomography (SPECT), CT, magnetic resonance and positron emission tomography (PET) Etc., step 3 is a differential diagnosis involving dementia. AD must be differentiated from vascular dementia. The Hachinski ischemic scale is commonly used.

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