Article

Prefrontal Neurons Predict Choices during an Auditory Same-Different Task

Department of Psychological and Brain Sciences, Center for Cognitive Neuroscience, Dartmouth College, Hanover, NH 03755, USA.
Current Biology (Impact Factor: 9.92). 10/2008; 18(19):1483-8. DOI: 10.1016/j.cub.2008.08.054
Source: PubMed

ABSTRACT The detection of stimuli is critical for an animal's survival [1]. However, it is not adaptive for an animal to respond automatically to every stimulus that is present in the environment [2-5]. Given that the prefrontal cortex (PFC) plays a key role in executive function [6-8], we hypothesized that PFC activity should be involved in context-dependent responses to uncommon stimuli. As a test of this hypothesis, monkeys participated in a same-different task, a variant of an oddball task [2]. During this task, a monkey heard multiple presentations of a "reference" stimulus that were followed by a "test" stimulus and reported whether these stimuli were the same or different. While they participated in this task, we recorded from neurons in the ventrolateral prefrontal cortex (vPFC; a cortical area involved in aspects of nonspatial auditory processing [9, 10]). We found that vPFC activity was correlated with the monkeys' choices. This finding demonstrates a direct link between single neurons and behavioral choices in the PFC on a nonspatial auditory task.

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    • "Beyond the auditory cortex, do latter processing stages (e.g., the monkey ventral prefrontal cortex and human inferior frontal cortex) process categories for even more complex sounds? A reexamination of previous findings from our lab (Russ et al., 2008b; Tsunada et al., 2011) indicated important differences in neural categorization between the lateral belt and the ventral prefrontal cortex (Figure 3). We found that, at the population level, the category sensitivity for speech sounds in the prefrontal cortex was weaker than that in the lateral belt although neural activity in the prefrontal cortex transmitted a significant amount of categorical information. "
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    Frontiers in Neuroscience 06/2014; 8:161. DOI:10.3389/fnins.2014.00161 · 3.70 Impact Factor
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    • "However, given the general role of the PFC in executive function (Miller and Cohen, 2001), we posit that examining vPFC activity during such passive-listening tasks is not an appropriate assay of the computations that occur in this brain region. Instead, when vPFC activity is examined during active behavioral tasks or more complex stimulus-presentation paradigms, it becomes clear that vPFC activity is involved in those functions that utilize vocalization information (and other auditory signals) to help guide goaldirected behaviors, including those behaviors that require nonspatial attention, working memory, decision-making, and abstract categorization (Gifford et al., 2005; Plakke et al., 2013a,b, 2012; Poremba et al., 2013; Russ et al., 2008a). "
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    • "These categories are represented in the ventral prefrontal cortex. Importantly, neural activity in the prefrontal cortex during categorization also predicts behavioral choice (Russ et al., 2008). Earlier in the stimulus-behavior transformation, these categories are differentially represented between interneurons and pyramidal neurons in the belt region of the auditory cortex (Tsunada et al., 2012), but this belt activity is not modulated by the monkey's categorical choices (Tsunada et al., 2011). "
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