Tactile Response

6-DUiydro-l-(2-hydroxyphenyl)-4-(-3-iiitrophenyl)-2(ltf)-pyrimidinone. (AKA IciUn, AG-3-5, CAS No. 36945-98-9, MW 311.3) 200 times more cooling than menthol. 4-Methyl-3-(l-pyrrolidinyl)-2[5H]-furanone. 35 times more powerful in the mouth, and 512 times more powerful on the skin than menthol, the active ingredient in mint, and the cooling effect lasts twice as long.  

Propanoic acid, 2-hydroxy-5-methyl-2-(l-methyletbyI) cyclobexyl ester, [1R-[1 alpha(R ), 

2 beta,5 alpha]]- (AKA 5-methyl-2-(l-methylethyl)-cyclohexyl-2-hydroxypropionate, (l)-Menthyl lactate, 1-menthyl lactatic acid-menthyl ester, Frescolat ML by Haarmann Reimer, CAS No. 59259-38-0, FEMA No. 3748, C13H24O3, MW 228.4) is faintly minty in odor and virtually tasteless, with a pleasant, long-lasting cooling effect.  

Source From Leffingwell, J.C., Cool without Menthol Cooler than Menthol. Leffingwell Associates, http //www.leffingwell.com/cooler than menthol.htm, 2001. 

Olfaction is the sensory component resulting from the interaction of volatile food components with olfactory receptors in the nasal cavity. We generally speak of the aroma or odor of a food. The stimulus for this sensation can be orthonasaL (the odor 

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The belt-and-braces sequence of sound + chemical => tactile response is explained by the necessity of perineal stimulation. In its absence defecation cannot begin, with lethal consequences. By 12 days, the pup s UHF response discriminates male and female adults calls are given only after removal of anaesthetised females, but not on male removal anosmia abolishes the discrimination unless an active female is present... 

Between about 3 and 4 dpf, larval movements and increasing tactile responsiveness necessitate anesthesia of larvae when detailed morphological assessments are performed. A 0.003% Tricaine solution is effective. 

Figure 4 Electrically evoked single-unit tactile responses recorded with microwire multielectrode arrays in rat hippocampus CA1, primary somatosensory cortex, and ventral posteromedial nucleus brain regions. (Upper) Raster plot of single-unit spikes before and after electrical current stimulation to whiskers. Each row is a separate trial. (Lower) Summed activity for all trials in 1-ms bins that demonstrate a response to electrical stimulation. The graphs show different latencies in firing for the three different regions. [Data reprinted from Ref. (1 3). Copyright (2007) National Academy of Sciences, U.S.]...

More recently, it has become clear that the RVM can facilitate as well as dampen pain (reviewed by Porreca et al. 2002). Stimulation of the RVM at relatively low current intensities increases the responses of spinal dorsal horn neurons to noxious stimuli. The role of this facilitation in chronic pain is suggested by studies showing that blockade of the RVM with lidocaine reduces abnormal tactile responses in rats with neuropathic pain (Pertovaara et al. 1996). Other studies of inflammatory and neuropathic pain converge in showing that descending facilitation is an important component of pathological pain. 

Since stearic acid is a solid that is virtually insoluble in saliva, this lipid is predicted to yield a minimal taste response when compared to long-chain fatty acids that are oils at physiological temperature. Saturated fats such as stearic acid produce insoluble mixtures in water that may cause both a tactile and a chemosensory response. However, hydrophobic chemosensory stimuli can be presented to subjects as complex emulsions of gum acacia, EDTA, water, and mineral oil that mask the viscosity of fatty acid stimuli [2,4,21,22, 77]. These emulsions may trigger a tactile response on the tongue surface, and may show heterogeneity in the distribution and amoimts of fatty acid that are suspended in the emulsion. 

More recently, stearic acid has been incorporated into edible strips that contain the polymers pullulan and hydroxypropyl methylcellulose [11]. With this delivery method, control strips and strips with taste stimuli yield similar tactile responses. In the presence of nasal airflow, Ebba et al. [11] reported that... 

One major limitation of taste studies in the human oral cavity is the lack of a standardized test that can be used for both hydrophilic and hydrophobic taste stimuli. In addition, long-chain saturated fats (such as stearic acid) often yield minimal gustatory responses in humans. This minimal response complicates the measurement of gustatory responses of long-chain saturated fats in the oral cavity. In order to advance the growing field of fatty acid chemoreception, improved delivery methods must be developed that allow sufficient amoimts of fatty acid to be presented to subjects for suprathreshold measurements while minimizing the tactile response of these stimuli. Under these conditions, a true gustatory response for fatty acids can be systematically examined in the human oral cavity. These studies could further identify whether some... 

On the tongue, the chemesthetic neurons are located in the papillae and are wrapped around the taste buds. The fungiform papillae, though lacking taste cells, possess chemesthetic neurons. These neurons make use of the structure of the taste bud to form a channel to the tongue surface. It has been reported that these neurons outnumber taste receptors nerves three to one [32]. The chemesthetic neurons are similar to taste receptors in that they have chemical specific receptors sites, however, they differ in that the neurons possess a set of other unique receptors. These receptors include mechanoreceptors for tactile response, thermoreceptors that detect temperature change, proprioceptors that detect motion, and nociceptors that mediate pain (comprise the somatosenses as a whole) [33]. 

The sensation of pain, following injury or disease, in response to a previously non-noxious stimulus is termed allodynia . Tactile allodynia is caused by... 

Cells communicate with each other in order to form and maintain the vertebrate body. Cells must know when and where to move, and what to do once they get there. This is accomplished by sending and receiving chemical, tactile, and perhaps even electrical signals (Cooper and Schliwa, 1986). Cells can be observed responding to at least some of these environmental cues in tissue culture, and also responding to each other. The response of cells to these factors is known as cell behavior. 

Association of Pain, neuropathic pain is defined as pain initiated or caused by a primary lesion, dysfunction in the nervous system". Neuropathy can be divided broadly into peripheral and central neuropathic pain, depending on whether the primary lesion or dysfunction is situated in the peripheral or central nervous system. In the periphery, neuropathic pain can result from disease or inflammatory states that affect peripheral nerves (e.g. diabetes mellitus, herpes zoster, HIV) or alternatively due to neuroma formation (amputation, nerve transection), nerve compression (e.g. tumours, entrapment) or other injuries (e.g. nerve crush, trauma). Central pain syndromes, on the other hand, result from alterations in different regions of the brain or the spinal cord. Examples include tumour or trauma affecting particular CNS structures (e.g. brainstem and thalamus) or spinal cord injury. Both the symptoms and origins of neuropathic pain are extremely diverse. Due to this variability, neuropathic pain syndromes are often difficult to treat. Some of the clinical symptoms associated with this condition include spontaneous pain, tactile allodynia (touch-evoked pain), hyperalgesia (enhanced responses to a painful stimulus) and sensory deficits. 

Fig. 5.8(b) VN-x and releasing hormone effects on female receptive behaviour facilitation by LHRH and latency to tactile induction of lordosis in hamster (latency duration, sec.). LHRH restores responsiveness over saline control (from Mackay-Sim and Rose, 1986). 

Features of central sensitization are pain in response to normally innocuous tactile stimuli, and the spread of pain sensitivity beyond the site of tissue injury. Central sensitization plays a major role in acute post-traumatic pain, and also in migraine, neuropathic pain (see below) and some diffuse chronic pain syndromes, such as fibromyalgia and irritable bowel syndrome. In these conditions, which have no detectable peripheral trigger, an autonomous central sensitization may be the pathology, increasing the gain in neuronal activity in the CNS and thereby producing abnormal responses to normal inputs. 

Using tactile startle, bufotenin, a hallucinogen that does not cross the blood-brain barrier readily, also produced biphasic dose-response effects when given intraventricularly (76). After systemic administration, however, low doses of indole hallucinogens have not been reported to increase tactile startle (73). Thus LSD (20-80 Mg/kg), DMT (0.25-1.0 mg/kg), and psilocin (2.5-5.0 mg/kg) did not increase tactile startle. A slightly higher dose of LSD (100 Mg/kg) did increase startle toward the end of the test session, perhaps because of blocking habituation (see below). 

Examples of common animal models that have been used over the last decade include the following (a) disruption of the conditioned avoidance response in rats (27), (b) mouse head twitch (43), (c) rabbit hyperthermia (1), (d) cat rage response (244) and cat limb flick (121), (e) mouse ear scratch (135,251), (f) flexor and stepping reflex in chronic spinal dog (140,143), (g) serotonin syndrome in rats (118), (h) tactile startle response in rats (68), and (i) two-lever drug discrimination in rats (84). 

Rabbit pups anticipate and prepare for the mother s vital, once-daily visit behaviourally and physiologically. An hour or so before the mother s arrival they become increasingly active, increasingly responsive to vibrational and tactile stimuli, and gradually uncover from the nest material (Hudson and Distel 1982). This enables them to reach the mother s ventrum unhindered and to start the rapid search for nipples the moment she stands over them. The anticipatory arousal is accompanied by a rise in pups (and mothers ) body temperature, and in the expression of... 

When using the term flavor , a certain inherent understanding of the term is evident. However, its use in the technical discussion of food requires a more imprecise definition. A common technical definition of the word flavor is the sum total of the sensory responses of taste and aroma combined with the general tactile and temperature responses to substances placed in the mouth. Flavor can also mean any individual substance or combination of substances used for the principal purpose of eliciting the latter responses. This latter usage will be the way in which the term is used in this chapter. 

In contrast to the limited information regarding the neurotoxicity of mirex, the neurotoxicity of chlordecone, which included tremoring and/or a time-dependent exaggerated startle response, was readily apparent in studies with experimental animals. Single oral doses of chlordecone resulted in increased tremoring and/or an exaggerated response to audio or tactile stimuli (Albertson et al. 

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