Chapter 15 Flashcards
Accross-Fiber patterns
The pattern of nerve firing that a stimulus creates across a number of neurons (distributed coding)
Amiloride
A substance that blocks the flow of sodium into taste receptors
Amygdala
subcortical structure that is involved in emotional responding and in processing olfactory signals
Bimodal neuron
A neron that response to stimuli associated with more than one sense
Calcium imaging
method of measuring receptor activity by using fluorescence to measure the concentration of calcium inside the receptor, has been used to measure the activation of olfactory receptor neurons
Chemotopic map
pattern of activation in the olfactory system in which chemicals with different properties create a “map” of activation based on these properties, for example there is eveidence that chemicals are mapped in the olfactory bulb based on carbon-chain length (odotopic/odor map)
Detection threshold
minimum amount of energy that can be detected - detection threshold for smell is the lowest concentration at which an oderant can be detected (recognition threshold requires a higher concentration)
Flavour
perception that occurs from the combination of taste and olfaction
Frontal operculum cortex
area in the frontal lobe of the cortex that receives signals from the taste system
Glomeruli
small structures in the olfactory bylb that receive signals from similar olfactory receptor neurons, one function of each glomerulus is to collect information about a small group of oderants
Insula
area in the frontal lobe of the cortex that receives signals from the taste system and is also involved in the affective component of pain perception
Macrosmatic
having a keen sense of smell; usually important to an animal’s survival
Microsmatic
Having a weak sense of smell; usually occurs in animals like humans where smell is not crucial for survival
Nasal Pharynx
passageway that connects mouth cavity and nasal passageway
Neurogenesis
occurs for olfaction and taste - cycle of birth, development and death of a neuron
Nontaster
a person who can not taste the compound phenylthiocarbamide (PTC)
Nucleus of solitary tract
The nucleus in the brain stem that receives signals from the tongue, mouth, and the larynx transmitted by the chorda tympani, glossopharyngeal, and vagus nerves
Odor map
pattern of activation in the olfactory system in which chemicals with different properties create a “map” of activation based on these properties, for example there is eveidence that chemicals are mapped in the olfactory bulb based on carbon-chain length (chemotopic/odotopic map)
Odor object
The source of an odor
Odotopic map
pattern of activation in the olfactory system in which chemicals with different properties create a “map” of activation based on these properties, for example there is eveidence that chemicals are mapped in the olfactory bulb based on carbon-chain length (chemotopic/odor map)
Olfaction
sense of smell, usually resulting from stimulation of receptors in the olfactory mucosa
Olfactometer
a device that presents olfactory stimuli with great precision
Olfactory bulb
the structure that receives signals directly from the olfactory receptors. THe olfactory bulb contains glomeruli, which receive these signals from the receptors.
Olfactory mucosa
The region inside the nose that contains the receptors for sense of smell
Olfactory receptor neurons (ORNs)
sensory neurons in olfactory mucosa that contain olfactory receptors
Olfactory receptors
a protein string that responds to odor stimuli
Optical imaging
technique to measure activity of large areas ont he olfactory bulb by measuring the intensity of red light reflected from the bulb
Oral capture
Condition in which sensations from olfaction and taste are perceived as being located in the mouth
Orbitofrontal cortex
area in frontal lobe near the eyes that receives signals originating in the olfactory receptors, also known as secondary olfactory cortex
Papillae
ridges and valleys of the tongue, some of which contain taste buds - filiform, fungiform, foliate, circumvallate
Pheremone
chemical signal released by an individual that affects the physiology and behaviour of other individuals
Piriform cortex
an area under the temporal lobe that receives signals from glomeruli in the olfactory bulb (primary olfactory cortex)
Primary olfactory area
small area under the temporal lobe that receives signals from glomeruli in the olfactory bulb. Also called piriform cortex.
Proust effect
Elicitation of memories through taste and olfaction, named for Proust who described unlocked childhood memories from taste and smell of tea soaked madeleine cake
Recognition profile
Pattern of olfactory activation for an odourant, indicating which ORNs are activated by the oderant
Recognition threshold
concentration at which the quality of an odour can be recognized
Retronasal route
opening from oral cavity, through nasal pharynx, into nasal cavity. The basis for how smell combines with taste to create flavour.
Secondary olfactory area
area in frontal lobe near the eyes that receives signals originating in the olfactory receptors, also known as orbitofrontal cortex
Sensory-specific satiety
The effect on perception of the odor associated with food eaten to satiety (i.e. full of bananas, odor is rated negative, vanilla odor is lessened but still positive)
Supertaster
A person especially sensitive to bitter substance 6-n-propylthiouracil (PROP)
Tastebud
A structure located within the papillae on the tongue that contains the taste cells
Taste cell
cells located in taste buds that causes the transduction of chemical to electrical energy when chemicals contact receptor sites or channels located at the tip of the cell
Taste pore
Opening in the taste bud through which the tips of the taste cell protrude. When chemicals enter a taste pore they stimulate the taste cell and result in transduction.
Taster
A person who can taste the compound phenythiocarbamide (PTC)
2-deoxyglucose technique
injecting a radioactive 2-deoxyglucose (2DG) molecule into an animal and exposing the animal to different chemicals. Glucose in 2DG is taken up by active neurons, so by measuring radioactivity in various parts of a structure we can determine which neurons are most activated by the different chemicals.
Video microscopy
a technique that has been used to take pictures of pappilae and taste buds on the tongue
Yes/No procedure
participants are given trials with odours along with blank trials, yes/no response, bias as participant chooses to respond
Forced choice
2 trials, one with and one without odorant, participant indicates which smells strongest.
Combinatorial code for odour
Malnic et al. from results of calcium imaging experiments, odourants coded by patterns of activation olfactory receptors called recognition profiles (the smell we recognize)
Filiform
shaped like cones – on entire surface (no taste buds)
Fungiform
shaped like mushrooms and found on sides and tip
Foliate
series of folds on back and sides
Circumvallate
shaped like flat mounds in a trench located at the back
Taste buds
10,000 w 50-100 taste cells (transduction occurs when chemicals contact receptor sites on tips)
