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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] |
Neurological Disorder
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 inter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Semantic Memory
Semantic memory refers to general world knowledge that humans have accumulated throughout their lives. This general knowledge (Semantics, word meanings, concepts, facts, and ideas) is intertwined in experience and dependent on culture. New concepts are learned by applying knowledge learned from things in the past. Semantic memory is distinct from episodic memory—the memory of experiences and specific events that occur in one's life that can be recreated at any given point. For instance, semantic memory might contain information about what a cat is, whereas episodic memory might contain a specific memory of stroking a particular cat. Semantic memory and episodic memory are both types of explicit memory, explicit memory (or declarative memory), or memory of facts or events that can be consciously recalled and "declared". The counterpart to declarative or explicit memory is implicit memory (also known as nondeclarative memory). History The idea of semantic memory was first intr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Visual Disturbances And Blindness
The visual system is the physiological basis of visual perception (the ability to detect and process light). The system detects, transduces and interprets information concerning light within the visible range to construct an image and build a mental model of the surrounding environment. The visual system is associated with the eye and functionally divided into the optical system (including cornea and lens) and the neural system (including the retina and visual cortex). The visual system performs a number of complex tasks based on the ''image forming'' functionality of the eye, including the formation of monocular images, the neural mechanisms underlying stereopsis and assessment of distances to (depth perception) and between objects, motion perception, pattern recognition, accurate motor coordination under visual guidance, and colour vision. Together, these facilitate higher order tasks, such as object identification. The neuropsychological side of visual information proces ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tom N
Tom or TOM may refer to: * Tom (given name), including a list of people and fictional characters with the name. Arts and entertainment Film and television * ''Tom'' (1973 film), or ''The Bad Bunch'', a blaxploitation film * ''Tom'' (2002 film), a documentary film * ''Tom'' (American TV series), 1994 * ''Tom'' (Spanish TV series), 2003 Music * ''Tom'', a 1970 album by Tom Jones * Tom drum, a musical drum with no snares * Tom (Ethiopian instrument), a plucked lamellophone thumb piano * Tune-o-matic, a guitar bridge design Places * Tom, Oklahoma, US * Tom (Amur Oblast), a river in Russia * Tom (river), in Russia, a right tributary of the Ob Science and technology * A male cat * A male wild turkey * Tom (pattern matching language), a programming language * TOM (psychedelic), a hallucinogen * Text Object Model, a Microsoft Windows programming interface * Theory of mind (ToM), in psychology * Translocase of the outer membrane, a complex of proteins Transportation * ''Tom'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Patient DF
Patient DF is a woman with visual apperceptive agnosia who has been studied extensively due to the implications of her behavior for the two streams theory of visual perception. Though her vision remains intact, she has trouble visually locating and identifying objects. Despite being unable to identify or recognize objects, DF can still use visual input to guide her action. Her agnosia is thought to be caused by a bilateral lesion to her lateral occipital cortex, an area thought by dual-stream proponents to be the ventral "object recognition" stream. Lesion Patient DF's brain damage resulted from hypoxia due to accidental carbon monoxide poisoning in 1988, when she was 34 years old. The lateral occipital cortex (LOC) in her brain is severely damaged and shows no activation presented with line drawings of common objects where healthy people usually do. Moreover, there is a reduction of white matter connections between LOC and other areas. There is also some shrinkage in the i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Visual Space
Visual space is the experience of space by an aware observer. It is the subjective counterpart of the space of physical objects. There is a long history in philosophy, and later psychology of writings describing visual space, and its relationship to the space of physical objects. A partial list would include René Descartes, Immanuel Kant, Hermann von Helmholtz, William James, to name just a few. Object space and visual space Space of physical objects The location and shape of physical objects can be accurately described with the tools of geometry. For practical purposes the space we occupy is Euclidean. It is three-dimensional and measurable using tools such as rulers. It can be quantified using co-ordinate systems like the Cartesian x,y,z, or polar coordinates with angles of elevation, azimuth and distance from an arbitrary origin. Space of visual percepts Percepts, the counterparts in the aware observer's conscious experience of objects in physical space, constitute ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aphasia
Aphasia, also known as dysphasia, is an impairment in a person's ability to comprehend or formulate language because of dysfunction in specific brain regions. The major causes are stroke and head trauma; prevalence is hard to determine, but aphasia due to stroke is estimated to be 0.1–0.4% in developed countries. Aphasia can also be the result of brain tumors, epilepsy, autoimmune neurological diseases, brain infections, or neurodegenerative diseases (such as dementias). To be diagnosed with aphasia, a person's language must be significantly impaired in one or more of the four aspects of communication. In the case of progressive aphasia, a noticeable decline in language abilities over a short period of time is required. The four aspects of communication include spoken language production, spoken language comprehension, written language production, and written language comprehension. Impairments in any of these aspects can impact functional communication. The difficulties o ... [...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] |
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] |
Alzheimer's Disease
Alzheimer's disease (AD) is a neurodegenerative disease and the cause of 60–70% of cases of dementia. The most common early symptom is difficulty in remembering recent events. As the disease advances, symptoms can include problems with language, disorientation (including easily getting lost), mood swings, loss of motivation, self-neglect, and behavioral issues. As a person's condition declines, they often withdraw from family and society. Gradually, bodily functions are lost, ultimately leading to death. Although the speed of progression can vary, the average life expectancy following diagnosis is three to twelve years. The causes of Alzheimer's disease remain poorly understood. There are many environmental and genetic risk factors associated with its development. The strongest genetic risk factor is from an allele of apolipoprotein E. Other risk factors include a history of head injury, clinical depression, and high blood pressure. The progression of the di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Visual Agnosia
Visual agnosia is an impairment in recognition of visually presented objects. It is not due to a deficit in vision (acuity, visual field, and scanning), language, memory, or intellect. While cortical blindness results from lesions to primary visual cortex, visual agnosia is often due to damage to more anterior cortex such as the posterior occipital and/or temporal lobe(s) in the brain. /sup> There are two types of visual agnosia, apperceptive and associative. Recognition of visual objects occurs at two levels. At an apperceptive level, the features of the visual information from the retina are put together to form a perceptual representation of an object. At an associative level, the meaning of an object is attached to the perceptual representation and the object is identified. If a person is unable to recognize objects because they cannot perceive correct forms of the objects, although their knowledge of the objects is intact (i.e. they do not have anomia), they have appercepti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cognitive Neuroscience Of Visual Object Recognition
Visual object recognition refers to the ability to identify the objects in view based on visual input. One important signature of visual object recognition is "object invariance", or the ability to identify objects across changes in the detailed context in which objects are viewed, including changes in illumination, object pose, and background context. Basic stages of object recognition Neuropsychological evidence affirms that there are four specific stages identified in the process of object recognition. These stages are: :Stage 1 Processing of basic object components, such as color, depth, and form. :Stage 2 These basic components are then grouped on the basis of similarity, providing information on distinct edges to the visual form. Subsequently, figure-ground segregation is able to take place. :Stage 3 The visual representation is matched with structural descriptions in memory. :Stage 4 Semantic attributes are applied to the visual representation, providing meaning, and the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
