The mouse is receiving growing interest as a model organism for studying visual perception. However, little is known about how discrimination and learning interact to produce visual conditioned responses. Here, we adapted a two-alternative forced-choice visual discrimination task for mice and examined how training with equiprobable stimuli of varying similarity influenced conditioned response a...

The present studies were carried out to investigate the effects of different retroactive stimuli on pitch discrimination in a short-term recognition memory task. Tones, Gaussian noise, and "Blank" stimuli were employed in the retroactive (interference) interval. Tones in the interference interval can enhance memory for pitch if the observer (0) employs the interference stimulus as a point of re...

Same/different discrimination is a classic task for investigating relational learning in animals. Recent research suggests that pigeons can learn a trial-unique same/different discrimination, which eliminates the opportunity to memorize the training items (Brooks & Wasserman, 2008). The authors conducted three tests to elucidate the role that item-based comparison plays in this trial-unique dis...

In this issue of Neuron, Uka and DeAngelis report a neural signature of the strategy that monkeys' brains developed to solve a visual discrimination task by training them on one version of the task and testing them on another. Extensive training on one version caused decision networks in the animals' brains to ignore certain classes of neurons whose signals would have been useful on the modifie...

In the present study, we investigated whether luminance and the side of response execution are associated, showing a SNARC-like effect (faster responses with the left hand for dark stimuli, and vice versa for light stimuli). A total of 30 participants were tested in two experiments. In Experiment 1, the association between space and the luminance of chromatic stimuli was directly tested (bright...

Does conceptual knowledge about objects influence their perceptual processing? There is some evidence for interactions between semantic and visual knowledge in tasks requiring both long-term memory and lexical access. Here we assessed whether similar perceptual/semantic interactions arise during sequential visual matching, a task that does not require access to semantic information. Matching of...

Brain activity during wakefulness is characterized by rapid fluctuations in neuronal responses. Whether these fluctuations play any role in modulating the accuracy of behavioral responses is poorly understood. Here, we investigated whether and how trial changes in the population response impact sensory coding in monkey V1 and perceptual performance. Although the responses of individual neurons ...

Absolute pitch (AP), the ability to name a musical note in the absence of a reference note, is extremely rare in the U.S. and Europe, and its genesis is unclear. The prevalence of AP was examined among students in an American music conservatory as a function of age of onset of musical training, ethnicity, and fluency in speaking a tone language. Taking those of East Asian ethnicity, the perform...

This experiment examined the generation of virtual pitch for harmonically related tones that do not overlap in time. The interval between successive tones was systematically varied in order to gauge the integration period for virtual pitch. A pitch discrimination task was employed, and both harmonic and nonharmonic tone series were tested. The results confirmed that a virtual pitch can be gener...