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Sensory-motor Coupling
Sensory-motor coupling is the coupling or integration of the sensory system and motor system. For a given stimulus, there is no one single motor command. "Neural responses at almost every stage of a sensorimotor pathway are modified at short and long timescales by biophysical and synaptic processes, recurrent and feedback connections, and learning, as well as many other internal and external variables". Overview The integration of the sensory and motor systems allows an animal to take sensory information and use it to make useful motor actions. Additionally, outputs from the motor system can be used to modify the sensory system's response to future stimuli. To be useful it is necessary that sensory-motor integration be a flexible process because the properties of the world and ourselves change over time. Flexible sensorimotor integration would allow an animal the ability to correct for errors and be useful in multiple situations. To produce the desired flexibility it's proba ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sensory System
The sensory nervous system is a part of the nervous system responsible for processing sensory information. A sensory system consists of sensory neurons (including the sensory receptor cells), neural pathways, and parts of the brain involved in sensory perception and interoception. Commonly recognized sensory systems are those for vision, hearing, touch, taste, smell, balance and visceral sensation. Sense organs are transducers that convert data from the outer physical world to the realm of the mind where people interpret the information, creating their perception of the world around them. The receptive field is the area of the body or environment to which a receptor organ and receptor cells respond. For instance, the part of the world an eye can see, is its receptive field; the light that each rod or cone can see, is its receptive field. Receptive fields have been identified for the visual system, auditory system and somatosensory system. Senses and receptors Whi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Auditory System
The auditory system is the sensory system for the sense of hearing. It includes both the ear, sensory organs (the ears) and the auditory parts of the sensory system. System overview The outer ear funnels sound vibrations to the eardrum, increasing the sound pressure in the middle frequency range. The Middle ear, middle-ear ossicles further amplify the vibration pressure roughly 20 times. The base of the stapes couples vibrations into the cochlea via the oval window, which vibrates the perilymph liquid (present throughout the inner ear) and causes the round window to bulb out as the oval window bulges in. Vestibular duct, Vestibular and tympanic ducts are filled with perilymph, and the smaller cochlear duct between them is filled with endolymph, a fluid with a very different ion concentration and voltage. Vestibular duct perilymph vibrations bend organ of Corti outer cells (4 lines) causing prestin to be released in cell tips. This causes the cells to be chemically elongated an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parietal Lobe
The parietal lobe is one of the four Lobes of the brain, major lobes of the cerebral cortex in the brain of mammals. The parietal lobe is positioned above the temporal lobe and behind the frontal lobe and central sulcus. The parietal lobe integrates sensory information among various sensory modality, modalities, including spatial sense and navigation (proprioception), the main sensory receptive area for the sense of touch in the somatosensory cortex which is just posterior to the central sulcus in the postcentral gyrus, and the two-streams hypothesis#Dorsal stream, dorsal stream of the visual system. The major sensory inputs from the skin (mechanoreceptor, touch, thermoreceptor, temperature, and nociceptor, pain receptors), relay through the thalamus to the parietal lobe. Several areas of the parietal lobe are important in language processing in the brain, language processing. The somatosensory cortex can be illustrated as a distorted figure – the cortical homunculus (Latin: "li ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vocal Tract
The vocal tract is the cavity in human bodies and in animals where the sound produced at the sound source (larynx in mammals; syrinx in birds) is filtered. In birds, it consists of the trachea, the syrinx, the oral cavity, the upper part of the esophagus, and the beak. In mammals, it consists of the laryngeal cavity, the pharynx, the oral cavity, and the nasal cavity. The estimated average length of the vocal tract in men is 16.9 cm and 14.1 cm in women. See also *Language Language is a structured system of communication that consists of grammar and vocabulary. It is the primary means by which humans convey meaning, both in spoken and signed language, signed forms, and may also be conveyed through writing syste ... * Talking birds – species of birds capable of imitating human sounds, but without known comprehension * Speech organ * Speech synthesis * Manner of articulation References {{Anatomy-stub Human head and neck Human voice Respiratory system anatom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Accent (dialect)
In sociolinguistics, an accent is a way of pronouncing a language that is distinctive to a country, area, social class, or individual. An accent may be identified with the locality in which its speakers reside (a regional or geographical accent), the socioeconomic status of its speakers, their ethnicity (an ethnolect), their caste or social class (a social accent), or influence from their first language (a foreign accent). Accents typically differ in quality of voice, pronunciation and distinction of vowels and consonants, stress, and prosody. Although grammar, semantics, vocabulary, and other language characteristics often vary concurrently with accent, the word "accent" may refer specifically to the differences in pronunciation, whereas the word "dialect" encompasses the broader set of linguistic differences. "Accent" is often a subset of "dialect". History As human beings spread out into isolated communities, stresses and peculiarities develop. Over time, they can develo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deafness
Deafness has varying definitions in cultural and medical contexts. In medical contexts, the meaning of deafness is hearing loss that precludes a person from understanding spoken language, an audiological condition. In this context it is written with a lower case ''d''. It later came to be used in a cultural context to refer to those who primarily communicate with a deafness aid or through sign language regardless of hearing ability, often capitalized as ''Deaf'' and referred to as "big D Deaf" in speech and sign. The two definitions overlap but are not identical, as hearing loss includes cases that are not severe enough to impact spoken language comprehension, while cultural Deafness includes hearing people who use sign language, such as children of deaf adults. Medical context In a medical context, deafness is defined as a degree of hearing difficulties such that a person is unable to understand speech, even in the presence of amplification. In profound deafness, eve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hearing (sense)
Hearing, or auditory perception, is the ability to perceive sounds through an organ, such as an ear, by detecting vibrations as periodic changes in the pressure of a surrounding medium. The academic field concerned with hearing is auditory science. Sound may be heard through solid Solid is a state of matter where molecules are closely packed and can not slide past each other. Solids resist compression, expansion, or external forces that would alter its shape, with the degree to which they are resisted dependent upon the ..., liquid, or gaseous matter. It is one of the traditional five senses. Partial or total inability to hear is called hearing loss. In humans and other vertebrates, hearing is performed primarily by the auditory system: mechanical waves, known as vibrations, are detected by the ear and transduction (physiology), transduced into nerve impulses that are perceived by the brain (primarily in the temporal lobe). Like touch, audition requires sensitivity ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Babbling
A babbling infant, age 6 months, making ''ba'' and ''ma'' sounds Babbling is a stage in child development and a state in language acquisition during which an infant appears to be experimenting with uttering articulate sounds, but does not yet produce any recognizable words. Babbling begins shortly after birth and progresses through several stages as the infant's repertoire of sounds expands and vocalizations become more speech-like. Infants typically begin to produce recognizable words when they are around 12 months of age, though babbling may continue for some time afterward. Babbling can be seen as a precursor to language development or simply as vocal experimentation. The physical structures involved in babbling are still being developed in the first year of a child's life. This continued physical development is responsible for some of the changes in abilities and variations of sound babies can produce. Abnormal developments such as certain medical conditions, developmen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Speech
Speech is the use of the human voice as a medium for language. Spoken language combines vowel and consonant sounds to form units of meaning like words, which belong to a language's lexicon. There are many different intentional speech acts, such as informing, declaring, asking, persuading, directing; acts may vary in various aspects like enunciation, Intonation (linguistics), intonation, loudness, and Speech tempo, tempo to convey meaning. Individuals may also unintentionally communicate aspects of their social position through speech, such as sex, age, place of origin, physiological and mental condition, education, and experiences. While normally used to facilitate communication with others, people may also use speech without the intent to communicate. Speech may nevertheless express emotions or desires; people Talking to oneself, talk to themselves sometimes in acts that are a development of what some psychologists (e.g., Lev Vygotsky) have maintained is the use of silent spee ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Speech Acquisition
Speech acquisition focuses on the development of vocal, acoustic and oral language by a child. This includes motor planning and execution, pronunciation, phonological and articulation patterns (as opposed to content and grammar which is language). Spoken speech consists of an organized set of sounds or phonemes that are used to convey meaning while language is an arbitrary association of symbols used according to prescribed rules to convey meaning. While grammatical and syntactic learning can be seen as a part of language acquisition, speech acquisition includes the development of speech perception and speech production over the first years of a child's lifetime. There are several models to explain the norms of speech sound or phoneme acquisition in children. Development of speech perception Sensory learning concerning acoustic speech signals already starts during pregnancy. Hepper and Shahidullah (1992) described the progression of fetal response to different pure tone freq ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corollary Discharge
In physiology, an efference copy or efferent copy is an internal copy of an outflowing (''Efferent nerve fiber, efferent''), movement-producing signal generated by an organism's motor system.Jeannerod, Marc (2003): "Action Monitoring and Forward Control of Movement". In: Michael Arbib (Ed.), ''The Handbook of Brain Theory and Neural Networks.'' Second Edition. Cambridge, Mass.: MIT Press, pp. 83–85, here: p. 83. It can be collated with the (reafferent) sensory input that results from the agent's movement, enabling a comparison of actual movement with desired movement, and a shielding of perception from particular self-induced effects on the sensory input to achieve perceptual stability. Together with internal model (motor control), internal models, efference copies can serve to enable the brain to predict the effects of an action. An equal term with a different history is ''corollary discharge''. Efference copies are important in enabling motor adaptation such as to enhance gaze ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Central Pattern Generator
Central pattern generators (CPGs) are self-organizing biological neural circuits that produce rhythmic outputs in the absence of rhythmic input. They are the source of the tightly-coupled patterns of neural activity that drive rhythmic and stereotyped motor behaviors like walking, swimming, breathing, or chewing. The ability to function without input from higher brain areas still requires modulatory inputs, and their outputs are not fixed. Flexibility in response to sensory input is a fundamental quality of CPG-driven behavior. To be classified as a rhythmic generator, a CPG requires: # "two or more processes that interact such that each process sequentially increases and decreases, and # that, as a result of this interaction, the system repeatedly returns to its starting condition." CPGs are found in humans and most other vertebrates, and in some invertebrates. Physiology CPG neurons CPG neurons can have different intrinsic membrane properties (see schematic). Some neurons ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
