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Agnosia
Agnosia is a neurological disorder characterized by an inability to process sensory information. Often there is a loss of ability to recognize objects, persons, sounds, shapes, or smells while the specific sense is neither defective nor is there any significant memory loss. It is usually associated with brain injury or neurological illness, particularly after damage to the occipitotemporal border, which is part of the ventral stream. Agnosia affects only a single modality, such as vision or hearing. More recently, a top-down interruption is considered to cause the disturbance of handling perceptual information. Types Visual agnosia Visual agnosia is a broad category that refers to a deficiency in the ability to recognize visual objects. Visual agnosia can be further subdivided into two different subtypes: apperceptive visual agnosia and associative visual agnosia. Individuals with apperceptive visual agnosia display the ability to see contours and outlines w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apperceptive Agnosia
Apperceptive agnosia is a neurological disorder characterized by failures in recognition due to a failure of perception. In contrast, associative agnosia is a type of agnosia where perception occurs but recognition still does not occur. When referring to apperceptive agnosia, visual and object agnosia are most commonly discussed; this occurs because apperceptive agnosia is most likely to present visual impairments. However, in addition to visual apperceptive agnosia there are also cases of apperceptive agnosia in other sensory areas. Auditory apperceptive agnosia Auditory apperceptive agnosia are impairments in audition that take place despite intact audiogram. In some cases the deficit is in the ability to recognize spoken words, and in other cases, may be a deficit in recognizing environmental sounds. In all cases individuals are able to read, write, name objects, and converse intelligently. Similar to visual impairments, the deficit arise because of damage in the primary se ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Associative Visual Agnosia
Associative visual agnosia is a form of visual agnosia. It is an impairment in Recall (memory), recognition or assigning meaning to a Stimulus (physiology), stimulus that is accurately perception, perceived and not associated with a generalized deficit in intelligence, memory, language or attention. The disorder appears to be very uncommon in a "pure" or uncomplicated form and is usually accompanied by other complex neuropsychological problems due to the nature of the etiology. Affected individuals can accurately distinguish the object, as demonstrated by the ability to draw a picture of it or categorize accurately, yet they are unable to identify the object, its features or its functions. Classification Agnosias are sensory modality specific, usually classified as Visual system, visual, Auditory system, auditory, or Somatosensory system, tactile. Associative visual agnosia refers to a subtype of visual agnosia, which was labeled by Lissauer (1890), as an inability to connect th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Auditory Agnosia
Auditory agnosia is a form of agnosia that manifests itself primarily in the inability to recognize or differentiate between sounds. It is not a defect of the ear or "hearing", but rather a neurological inability of the brain to process sound meaning. While auditory agnosia impairs the understanding of sounds, other abilities such as reading, writing, and speaking are not hindered. It is caused by bilateral damage to the anterior superior temporal gyrus, which is part of the auditory pathway responsible for sound recognition, the auditory "what" pathway. Persons with auditory agnosia can physically hear the sounds and describe them using unrelated terms, but are unable to recognize them. They might describe the sound of some environmental sounds, such as a motor starting, as resembling a lion roaring, but would not be able to associate the sound with "car" or "engine", nor would they say that it ''was'' a lion creating the noise. All auditory agnosia patients read lips in order ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Auditory Verbal Agnosia
Auditory verbal agnosia (AVA), also known as pure word deafness, is the inability to comprehend speech. Individuals with this disorder lose the ability to understand language, repeat words, and write from dictation. Some patients with AVA describe hearing spoken language as meaningless noise, often as though the person speaking was doing so in a foreign language. However, spontaneous speaking, reading, and writing are preserved. The maintenance of the ability to process non-speech auditory information, including music, also remains relatively more intact than spoken language comprehension. Individuals who exhibit pure word deafness are also still able to recognize non-verbal sounds. The ability to interpret language via lip reading, hand gestures, and context clues is preserved as well. Sometimes, this agnosia is preceded by cortical deafness; however, this is not always the case. Researchers have documented that in most patients exhibiting auditory verbal agnosia, the discriminati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Autotopagnosia
Autotopagnosia from the Greek ''a'' and ''gnosis,'' meaning "without knowledge", ''topos'' meaning "place", and ''auto'' meaning "oneself", autotopagnosia virtually translates to the "lack of knowledge about one's own space," and is clinically described as such. Autotopagnosia is a form of agnosia, characterized by an inability to localize and orient different parts of the body. The psychoneurological disorder has also been referred to as "body-image agnosia" or "somatotopagnosia." ''Somatotopagnosia'' has been argued to be a better suited term to describe the condition. While autotopagnosia emphasizes the deficiencies in localizing only one's own body parts and orientation, ''somatotopagnosia'' also considers the inability to orient and recognize the body parts of others or representations of the body (e.g., manikins, diagrams). Typically, the cause of autotopagnosia is a lesion found in the parietal lobe of the left hemisphere of the brain. However, it as also been noted that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Astereognosis
Astereognosis (or tactile agnosia if only one hand is affected) is the inability to identify an object by active touch of the hands without other sensory input, such as visual or sensory information. An individual with astereognosis is unable to identify objects by handling them, despite intact elementary tactile, proprioceptive, and thermal sensation. With the absence of vision (i.e. eyes closed), an individual with astereognosis is unable to identify what is placed in their hand based on cues such as texture, size, spatial properties, and temperature. As opposed to agnosia, when the object is observed visually, one should be able to successfully identify the object. Individuals with tactile agnosia may be able to identify the name, purpose, or origin of an object with their left hand but not their right, or vice versa, or both hands. Astereognosis refers specifically to those who lack tactile recognition in both hands. In the affected hand(s) they may be able to identify basic s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Akinetopsia
Akinetopsia (from Greek ''akinesia'' 'absence of movement' and ''opsis'' 'seeing'), also known as cerebral akinetopsia or motion blindness, is an extremely rare neuropsychological disorder, having only been documented in a handful of medical cases, in which a patient cannot perceive motion in their visual field, despite being able to see stationary objects without issue. The syndrome is the result of damage to visual area V5, whose cells are specialized to detect directional visual motion. There are varying degrees of akinetopsia: from seeing motion as frames of a cinema reel to an inability to discriminate any motion. There is currently no effective treatment or cure for akinetopsia. Signs and symptoms Akinetopsia can manifest in a spectrum of severity and some cases may be episodic or temporary. It may range from "inconspicuous akinetopsia" to "gross akinetopsia", based on symptom severity and the amount the akinetopsia affects the patient's quality of life. Inconspicuous akin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anosognosia
Anosognosia is a condition in which a person with a disability is cognitively unaware of having it due to an underlying physical condition. Anosognosia results from physiological damage to brain structures, typically to the parietal lobe or a diffuse lesion on the fronto-temporal-parietal area in the right hemisphere, and is thus a neuropsychiatric disorder. A deficit of self-awareness, the term was first coined by the neurologist Joseph Babinski in 1914, in order to describe the unawareness of hemiplegia. Phenomenologically, anosognosia has similarities to denial, which is a psychological defense mechanism; attempts have been made at a unified explanation. The name derives from Ancient Greek: ἀ-, ''a-'' ('without'), νόσος, ''nosos ('''disease'), and γνῶσις, ''gnōsis'' ('knowledge'). It is considered a disorder that makes the treatment of the patient more difficult, since it may affect negatively the therapeutic relationship. Anosognosia is sometim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Recognition Memory
Recognition memory, a subcategory of explicit memory, is the ability to recognize previously encountered events, objects, or people.Medina, J. J. (2008)The biology of recognition memory. ''Psychiatric Times''. When the previously experienced event is reexperienced, this environmental content is matched to stored memory representations, eliciting matching signals. As first established by psychology experiments in the 1970s, recognition memory for pictures is quite remarkable: humans can remember thousands of images at high accuracy after seeing each only once and only for a few seconds.Standing, L. (1973). "Learning 10,000 pictures". ''The Quarterly Journal of Experimental Psychology'', 25(2), 207–222. Retrieved Jan 20 2020, from . Recognition memory can be subdivided into two component processes: recollection and familiarity, sometimes referred to as "remembering" and "knowing", respectively. Recollection is the retrieval of details associated with the previously experienced event ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neurological Illness
Neurological disorders represent a complex array of medical conditions that fundamentally disrupt the functioning of the nervous system. These disorders affect the brain, spinal cord, and nerve networks, presenting unique diagnosis, treatment, and patient care challenges. At their core, they represent disruptions to the intricate communication systems within the nervous system, stemming from genetic predispositions, environmental factors, infections, structural abnormalities, or degenerative processes. The impact of neurological disorders is profound and far-reaching. Conditions like epilepsy create recurring seizures through abnormal electrical brain activity, while multiple sclerosis damages the protective myelin covering of nerve fibers, interrupting communication between the brain and body. Parkinson's disease progressively affects movement through the loss of dopamine-producing nerve cells, and strokes can cause immediate and potentially permanent neurological damage by interr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lesion
A lesion is any damage or abnormal change in the tissue of an organism, usually caused by injury or diseases. The term ''Lesion'' is derived from the Latin meaning "injury". Lesions may occur in both plants and animals. Types There is no designated classification or naming convention for lesions. Because lesions can occur anywhere in the body and their definition is so broad, the varieties of lesions are virtually endless. Generally, lesions may be classified by their patterns, sizes, locations, or causes. They can also be named after the person who discovered them. For example, Ghon lesions, which are found in the lungs of those with tuberculosis, are named after the lesion's discoverer, Anton Ghon. The characteristic skin lesions of a varicella zoster virus infection are called '' chickenpox''. Lesions of the teeth are usually called dental caries, or "cavities". Location Lesions are often classified by their tissue types or locations. For example, "skin lesions" or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
