Psycholinguistic variables matter in odor naming

People from Western societies generally find it difficult to name odors. In trying to explain this, the olfactory literature has proposed several theories that focus heavily on properties of the odor itself but rarely discuss properties of the label used to describe it. However, recent studies show speakers of languages with dedicated smell lexicons can name odors with relative ease. Has the role of the lexicon been overlooked in the olfactory literature? Word production studies show properties of the label, such as word frequency and semantic context, influence naming; but this field of research focuses heavily on the visual domain. The current study combines methods from both fields to investigate word production for olfaction in two experiments. In the first experiment, participants named odors whose veridical labels were either high-frequency or low-frequency words in Dutch, and we found that odors with high-frequency labels were named correctly more often. In the second experiment, edibility was used for manipulating semantic context in search of a semantic interference effect, presenting the odors in blocks of edible and inedible odor source objects to half of the participants. While no evidence was found for a semantic interference effect, an effect of word frequency was again present. Our results demonstrate psycholinguistic variables-such as word frequency-are relevant for olfactory naming, and may, in part, explain why it is difficult to name odors in certain languages. Olfactory researchers cannot afford to ignore properties of an odor's label

Spontaneous angular momentum generation of two-dimensional fluid flow in an elliptic geometry

Spontaneous spin-up, i.e. the significant increase of the total angular momentum of a flow that initially has no net angular momentum, is very characteristic for decaying two-dimensional turbulence in square domains bounded by rigid no-slip walls. In contrast, spontaneous spin-up is virtually absent for such flows in a circular domain with a no-slip boundary. In order to acquire understanding of this strikingly different behavior observed on the square and the circle we consider a set of elliptic geometries with a gradual increase of the eccentricity. It is shown that a variation of the eccentricity can be used as a control parameter to tune the relative contribution of the pressure and viscous stresses in the angular momentum balance. Direct numerical simulations demonstrate that the magnitude of the torque can be related to the relative contribution of the pressure. As a consequence, the number of spin-up events in an ensemble of slightly different initial conditions strongly depends on the eccentricity.For small eccentricities strong and rapid spin-up events are observed occasionally, whereas the majority of the runs does not show significant spin-up. Small differences in the initial condition can result in a completely different evolution of the flow and appearance of the end-state of the decay process. For sufficiently large eccentricities all the runs in the ensemble demonstrate strong and rapid spin-up, which is consistent with the flow development on the square. It is verified that the number of spin-up events for a given eccentricity does not depend on the Reynolds number of the flow. This observation is consistent with the conjecture that it is the pressure on the domain boundaries thatdrives the spin-up processes

Motor-induced visual motion: hand movements driving visual motion perception

Visual perception can be changed by co-occurring input from other sensory modalities. Here, we explored how self-generated finger movements (left–right or up–down key presses) affect visual motion perception. In Experiment 1, motion perception of a blinking bar was shifted in the direction of co-occurring hand motor movements, indicative of motor-induced visual motion (MIVM). In Experiment 2, moving and static blinking bars were combined with either directional moving or stationary hand motor movements. Results showed that the directional component in the hand movement was crucial for MIVM as stationary motor movements even declined visual motion perception. In Experiment 3, the role of response bias was excluded in a two-alternative forced-choice task that ruled out the effect of response strategies. All three experiments demonstrated that alternating key presses (either horizontally or vertically aligned) induce illusory visual motion and that stationary motor movements (without a vertical or horizontal direction) induce the opposite effect, namely a decline in visual motion (more static) perception. Keywords: Visual motion perception, Motor visual, Multisensory, Visual ambiguity, Motor actio