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Diagnostic tests in respiratory medicine
Published in Vibeke Backer, Peter G. Gibson, Ian D. Pavord, The Asthmas, 2023
Vibeke Backer, Peter G. Gibson, Ian D. Pavord
Many types of sensory receptors respond to mechanical, inflammatory, thermal and chemical stimuli. They are connected to the vagal afferent nerves. Recently, it has been demonstrated that cough reflex sensitivity, though transiently enhanced during acute upper-airway infection, remains stable during the first week of illness. Underlying causes of chronic cough in many patients are hypersensitivity of the afferent sensory neurons in the mucosal lining of the airway and overexpressed C-fibre receptors. There is evidence that hypersensitisation in the central nervous system may contribute to chronic cough as well. This overreaction results in coughing due to a variety of stimuli.
Computations on the Nervous System: Some Results
Published in Theodore B. Achacoso, William S. Yamamoto, AY's Neuroanatomy of C. elegans for Computation, 2022
Theodore B. Achacoso, William S. Yamamoto
To estimate a lowest frequency, one must consider adaptation. This differs according to neuron type. Some sensory receptors show very low adaptation and are functionally low-pass. Others, like most interneurons, adapt quickly, perhaps, as briefly as the postsynaptic potentials. If the adaptation time is taken as the time constant for the low frequency cutoff, one gets an estimate of the slowest effective signal. In a low-pass system, however small the input signal angular velocity (magnitude x), if the threshold is S > 0, eventually, after a time interval, xT > S, and the spacing xT = nπ. Alternatively, threshold may be used to determine a lowest frequency f = 1/2T = S/2π. Threshold appears to be an independent variable of the system, not necessarily related to R. In a bandpass system, both S and kernel participate through convolution with the input signal to determine the lowest effective frequency for impulse transmission. This characteristic, however, pertains to temporal summation, and does not necessarily affect the significance of delimited long interspike intervals. The bandwidth of a neuron may thus be estimated to lie between an upper bound f = 1/2R (500 hz) and a lower bound which may be estimated in terms of convolution kernel and threshold. The lower bound, however, does not appear to limit the range of signal magnitudes, but rather, the amount of error tolerated in establishing logical coincidences.
“Paradise Room”
Published in Paul A. Rodgers, Design for People Living with Dementia, 2022
The world is a sensory place, and through sensorial input, our mind stays connected with this world. “Sensory information is the fuel that makes the brain work” (Dunn, 2008: 18). Usually, we are flooded with sensations to one extent or another all day long – be it at home, on the street, or in the park, cooking, dancing, walking. Most of the time we are not aware of the endless flow of sensory information our brain is receiving. The significance of sensory stimulation to keep our brain active and healthy is often undervalued in favour of the cognitive. Being constantly deprived of sensory stimulation results in a significant decrease in well-being and health (Kovach, 2000). Multi-sensory impairment, the age-associated worsening of sensory function and declining performance of sensory receptors (e.g. eyes and ears) therefore not only has social and psychological implications (leading to isolation, loneliness, and depression) but can also impact cognitive function, increasing the risk of dementia (Brenowitz et al., 2020; Hwang et al., 2020).
Exploration of a novel physical therapy protocol that uses a sensory substitution device to improve the standing postural balance of children with balance disorders
Published in Physiotherapy Theory and Practice, 2022
Swati M. Surkar, Regina Harbourne, Brad Corr, David Arpin, Max J.Kurz
Sensory substitution is a method of delivering alternative sensory information obtained from an artificial sensory receptor to the brain via an intact sensory pathway (Bach-y-Rita, 1990). A primary principle of sensory substitution is that the loss of sensory information from one sensory modality can be replaced with inputs from another sensory modality. The organization of the brain is highly adaptive to the type of feedback it receives and the cross-modal recruitment theories of plasticity explain the replacement of one sensory system with sensory inputs from other systems (Collignon et al., 2011; Ptito, Moesgaard, Gjedde, and Kupers, 2005). Prior studies have established that the brain is capable of using this alternative sensory information and will reorganize itself to improve its function (Bach-y-Rita, Danilov, Tyler, and Grimm, 2005). For example, individuals who lose vision learn to ‘see’ words using the sense of touch instead of vision (Theoret, Merabet, and Pascual-Leone, 2004). Older individuals relied on vision when vestibular information was reduced (Alberts, de Brouwer, Selen, and Medendorp, 2016). Further evidence points to functional magnetic imaging (fMRI) studies showing that the visual cortex is active when blind individuals read braille (Sadato, 2005). Thus, it is possible that the brain is also capable of incorporating new and alternative sensory information provided by an augmentative device (Bach-y-Rita, Danilov, Tyler, and Grimm, 2005).
Evaluation of oral mechanical and gustatory sensitivities and salivary cotinine levels in adult smokers
Published in Acta Odontologica Scandinavica, 2020
Mariana Belardinelli Rosa, Mariana dos Santos Fernandes, Leonardo Rigoldi Bonjardim, Maria Beatriz Duarte Gavião, Leandro Augusto Calixto, Paula Midori Castelo
The sensory system is composed of sensory receptors, that is, structures responsible for the perception of stimuli from the environment and from the interior of the body. Taste is a chemical sense that allows the individual to select specific substances according to their wishes and according to the metabolic needs of the body tissues [10], which prepares the gastrointestinal system to receive food and influencing salivation and swallowing (or the pharyngeal reflex – choking – if the substance is unpleasant). According to Strapasson et al. [11], smell and taste disorders considerably reduce the quality of life and may even become severe, as people with reduced taste and odour sensitivity may try to compensate for these losses by increasing the intake of substances that may be harmful if ingested in excess.
Effect of Force Sense to Active Joint Position Sense and Relationships between Active Joint Position Sense, Force Sense, Jumping and Muscle Strength
Published in Journal of Motor Behavior, 2020
Haydar Kaynak, Muammer Altun, Serdar Tok
Studies investigating knee proprioception have mainly focused on active JPS assessment without applying any external loads to muscles (Foch & Milner, 2013). However, there are external loads acting on the muscles and joints, such as acceleration, deceleration, jumping to certain heights, and the defensive actions of opponents (Carr, 1997; Laszlo, 1992). These issues might additionally deteriorate sport movement efficiency. Thus, the proprioceptive acuity should be tested under load as the knee is normally affected by these external loads during athletic activity. Joint loading variables could influence the degree of afferent input provided when the participant is required to make a judgment about the joint position in space (Bullock-Saxton, Wong, & Hogan, 2001). To execute functional movements in daily activities, exercise, and sports, proprioceptive information from a variety of mechanoreceptors is available for central processing. The senses of effort, force, and heaviness are traditionally believed to be generated by signals of central origin associated with motor commands. Peripheral sensory receptors are also available to contribute to the sensation, including tendon organs, muscle spindles, and pressure-sensitive skin receptors. The load applied in the JPS test may increase the proprioceptive information to the central processing and therefore repositioning errors may be reduced.