The lesions of several other oral conditions are sometimes described as aphthae, including Bednars aphthae (infected, traumatic ulcers on the hard palate in infants), oral candidiasis, and foot-and-mouth disease. When used without qualification, aphthae commonly refers to lesions of recurrent aphthous stomatitis. Since the word aphtha is often taken to be synonymous with ulcer, it has been suggested that the term "aphthous ulcer" is redundant, but it remains in common use. Stomatitis is also a non-specific term referring to any inflammatory process in the mouth, with or without oral ulceration. It may describe many different conditions apart from aphthous stomatitis such as angular stomatitis. The current most widely used medical term is "recurrent aphthous stomatitis" or simply "aphthous stomatitis". Historically, many different terms have been used to refer to recurrent aphthous stomatitis or its sub-types, and some are still in use. Mikuliczs aphthae is a synonym of minor RAS, named after Jan Mikulicz-Radecki. Synonyms for major RAS include Suttons ulcers (named after Richard Lightburn Sutton), Suttons disease, Suttons syndrome and periadenitis mucosa necrotica recurrens. Synonyms for aphthous stomatitis as a whole include (recurrent) oral aphthae, (recurrent) aphthous ulceration and (oral) aphthosis.In traditional Chinese medicine, claimed treatments for aphthae focus on clearing heat and nourishing Yin.Rembrandt Gentle White toothpaste did not contain sodium lauryl sulfate, and was specifically marketed as being for the benefit of "canker sore sufferers".
The brain must correctly integrate features such as edges, light intensity, and color from sensory information to form a complete percept of an object. If a failure occurs during this process, a percept of an object is not fully formed and thus it cannot be recognized. Tasks requiring copying, matching, or drawing simple figures can distinguish the individuals with apperceptive agnosia because they cannot perform such tasks.Associative agnosia is an inability to identify objects even with apparent perception and knowledge of them. It involves a higher level of processing than apperceptive agnosia. Individuals with associative agnosia can copy or match simple figures, indicating that they can perceive objects correctly. They also display the knowledge of objects when tested with tactile or verbal information. However, when tested visually, they cannot name or describe common objects. This means that there is an impairment in associating the perception of objects with the stored knowledge of them.Although visual agnosia can be general, there exist many variants that impair recognition of specific types. These variants of visual agnosia include prosopagnosia (inability to recognize faces), pure word blindness (inability to recognize words, often called "agnosic alexia" or "pure alexia"), agnosias for colors (inability to differentiate colors), agnosias for the environment (inability to recognize landmarks or difficulty with spatial layout of an environment, i.e. topographagnosia) and simultanagnosia (inability to sort out multiple objects in a visual scene). Categories and subtypes of visual agnosia
The two main categories of visual agnosia are:

Apperceptive visual agnosia, impaired object recognition.