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Phonetotopy
Phonetotopy is the concept that articulatory features as well as perceptual features of speech sounds are ordered in the brain in a similar way as tone (tonotopy), articulation and its somatosensory feedback (somatotopy), or visual location of an object (retinotopy). It is assumed that a phonetotopic ordering of speech sounds as well as of syllables can be found at a ''supramodal'' speech processing level (i.e. at a ''phonetic'' speech processing level) within the brain. The concept of phonetotopy was introduced in Kröger et al. (2009) on the basis of modeling speech production, speech perception, as well as speech acquisition. Moreover, fMRI measurements on ordering of vowels with respect to phonetic features as well as EEG, EEG-array measurements on vowel and syllable articulationKristofer E. Bouchard KE, Mesgarani N, Johnson K, Chang EF (2013) Functional organization of human sensorimotor cortex for speech articulation. Nature 495, 327–332 support this concept. The concept of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tonotopy
In physiology, tonotopy (from Greek tono = frequency and topos = place) is the spatial arrangement of where sounds of different frequency are processed in the brain. Tones close to each other in terms of frequency are represented in topologically neighbouring regions in the brain. Tonotopic maps are a particular case of topographic organization, similar to retinotopy in the visual system. Tonotopy in the auditory system begins at the cochlea, the small snail-like structure in the inner ear that sends information about sound to the brain. Different regions of the basilar membrane in the organ of Corti, the sound-sensitive portion of the cochlea, vibrate at different sinusoidal frequencies due to variations in thickness and width along the length of the membrane. Nerves that transmit information from different regions of the basilar membrane therefore encode frequency tonotopically. This tonotopy then projects through the vestibulocochlear nerve and associated midbrain structures ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Somatotopy
Somatotopy is the point-for-point correspondence of an area of the body to a specific point on the central nervous system. Typically, the area of the body corresponds to a point on the primary somatosensory cortex (postcentral gyrus). This cortex is typically represented as a sensory homunculus which orients the specific body parts and their respective locations upon the homunculus. Areas such as the appendages, digits, penis, and face can draw their sensory locations upon the somatosensory cortex. The areas which are finely controlled (e.g., the digits) have larger portions of the somatosensory cortex whereas areas which are coarsely controlled (e.g., the trunk) have smaller portions. Areas such as the viscera do not have sensory locations on the post central gyrus. Macaques, a kind of monkey, already exhibit somatotopy in their somatosensory and motor systems at birth. Sensorimotor mapping of the human cerebellum Functional magnetic resonance imaging (fMRI) was employed to dete ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Retinotopy
Retinotopy (from Greek τόπος, place) is the mapping of visual input from the retina to neurons, particularly those neurons within the visual stream. For clarity, 'retinotopy' can be replaced with 'retinal mapping', and 'retinotopic' with 'retinally mapped'. Visual field maps (retinotopic maps) are found in many amphibian and mammalian species, though the specific size, number, and spatial arrangement of these maps can differ considerably. Sensory topographies can be found throughout the brain and are critical to the understanding of one's external environment. Moreover, the study of sensory topographies and retinotopy in particular has furthered our understanding of how neurons encode and organize sensory signals. Retinal mapping of the visual field is maintained through various points of the visual pathway including but not limited to the retina, the dorsal lateral geniculate nucleus, the optic tectum, the primary visual cortex (V1), and higher visual areas (V2-V4). Retin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
FMRI
Functional magnetic resonance imaging or functional MRI (fMRI) measures brain activity by detecting changes associated with blood flow. This technique relies on the fact that cerebral blood flow and neuronal activation are coupled. When an area of the brain is in use, blood flow to that region also increases. The primary form of fMRI uses the blood-oxygen-level dependent (BOLD) contrast, discovered by Seiji Ogawa in 1990. This is a type of specialized brain and body scan used to map neural activity in the brain or spinal cord of humans or other animals by imaging the change in blood flow ( hemodynamic response) related to energy use by brain cells. Since the early 1990s, fMRI has come to dominate brain mapping research because it does not involve the use of injections, surgery, the ingestion of substances, or exposure to ionizing radiation. This measure is frequently corrupted by noise from various sources; hence, statistical procedures are used to extract the underlying signal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Distinctive Features
In linguistics, a distinctive feature is the most basic unit of phonological structure that distinguishes one sound from another within a language. For example, the feature oicedistinguishes the two bilabial plosives: and There are many different ways of defining and arranging features into ''feature systems'': some deal with only one language while others are developed to apply to all languages. Distinctive features are grouped into categories according to the natural classes of segments they describe: major class features, laryngeal features, manner features, and place features. These feature categories in turn are further specified on the basis of the phonetic properties of the segments in question. For phonemes to be in a particular natural class, they have to share the same distinctive features such as articulation and/or sound similar to each other. We can find distinctive features between two words by finding the minimal pair between them. The minimal pair are when tw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phonology
Phonology is the branch of linguistics that studies how languages or dialects systematically organize their sounds or, for sign languages, their constituent parts of signs. The term can also refer specifically to the sound or sign system of a particular language variety. At one time, the study of phonology related only to the study of the systems of phonemes in spoken languages, but may now relate to any linguistic analysis either: Sign languages have a phonological system equivalent to the system of sounds in spoken languages. The building blocks of signs are specifications for movement, location, and handshape. At first, a separate terminology was used for the study of sign phonology ('chereme' instead of 'phoneme', etc.), but the concepts are now considered to apply universally to all human languages. Terminology The word 'phonology' (as in 'phonology of English') can refer either to the field of study or to the phonological system of a given language. This is one ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neuroscience
Neuroscience is the science, scientific study of the nervous system (the brain, spinal cord, and peripheral nervous system), its functions and disorders. It is a Multidisciplinary approach, multidisciplinary science that combines physiology, anatomy, molecular biology, developmental biology, cytology, psychology, physics, computer science, chemistry, medicine, statistics, and Mathematical Modeling, mathematical modeling to understand the fundamental and emergent properties of neurons, glia and neural circuits. The understanding of the biological basis of learning, memory, behavior, perception, and consciousness has been described by Eric Kandel as the "epic challenge" of the Biology, biological sciences. The scope of neuroscience has broadened over time to include different approaches used to study the nervous system at different scales. The techniques used by neuroscientists have expanded enormously, from molecular biology, molecular and cell biology, cellular studies of indivi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phonetics
Phonetics is a branch of linguistics that studies how humans produce and perceive sounds, or in the case of sign languages, the equivalent aspects of sign. Linguists who specialize in studying the physical properties of speech are phoneticians. The field of phonetics is traditionally divided into three sub-disciplines based on the research questions involved such as how humans plan and execute movements to produce speech ( articulatory phonetics), how various movements affect the properties of the resulting sound ( acoustic phonetics), or how humans convert sound waves to linguistic information ( auditory phonetics). Traditionally, the minimal linguistic unit of phonetics is the phone—a speech sound in a language which differs from the phonological unit of phoneme; the phoneme is an abstract categorization of phones. Phonetics deals with two aspects of human speech: production—the ways humans make sounds—and perception—the way speech is understood. The communicative moda ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
