Ruidong Chen

• Postdoc at MIT

We use our experiences to form and update beliefs about the hidden states of the world. When possible, we also gather evidence by observing others. However, how the brain integrates experiential and observational evidence is not understood. We studied the dynamics of evidence integration in a two-player game with volatile hidden states. Both humans...

Mistakes in performance feel disappointing, suggesting that brain pathways for aversive feedback may play a role in motor learning. Here we tested if the lateral habenula (LHb), an evolutionarily conserved part of the limbic system known in mammals to relay aversive feedback from ventral pallidum (VP) to ventral tegmental area (VTA) dopamine neuron...

Mistakes in performance feel disappointing, suggesting that brain pathways for aversive feedback may play a role in motor learning. Here we tested if the lateral habenula (LHb), an evolutionarily conserved part of the limbic system known in mammals to relay aversive feedback from ventral pallidum (VP) to ventral tegmental area (VTA) dopamine neuron...

Mistakes in performance feel disappointing, suggesting that brain pathways for aversive feedback may play a role in motor learning. Here we tested if the lateral habenula (LHb), an evolutionarily conserved part of the limbic system known in mammals to relay aversive feedback from ventral pallidum (VP) to ventral tegmental area (VTA) dopamine neuron...

Movement-related neuronal discharge in ventral tegmental area (VTA) and ventral pallidum (VP) is inconsistently observed across studies. One possibility is that some neurons are movement-related and others are not. Another possibility is that the precise behavioral conditions matter - that a single neuron can be movement related under certain behav...

It feels rewarding to ace your opponent on match point. Here, we propose common mechanisms underlie reward and performance learning. First, when a singing bird unexpectedly hits the right note, its dopamine (DA) neurons are activated as when a thirsty monkey receives an unexpected juice reward. Second, these DA signals reinforce vocal variations mu...

Movement-related neuronal discharge in ventral tegmental area (VTA) and ventral pallidum (VP) is inconsistently observed across studies. One possibility is that some neurons are movement-related and others are not. Another possibility is that the precise behavioral conditions matter - that a single neuron can be movement related under certain behav...

Motor skills improve with practice, requiring outcomes to be evaluated against ever-changing performance benchmarks, yet it remains unclear how performance error signals are computed. Here, we show that the songbird ventral pallidum (VP) is required for song learning and sends diverse song timing and performance error signals to the ventral tegment...

Ventral tegmental area (VTA) dopamine neurons contribute to reinforcement learning by signaling prediction error, the difference between actual and predicted outcome, but it remains unclear how error is computed. Here we identify in songbirds that a VTA-projecting ventral basal ganglia (vBG) region outside the classic song system is required for so...

Proteins, synapses, and neural connections are in constant flux, yet motor behaviors somehow remain stable. In this issue of Neuron, Katlowitz et al. (2018) show that temporally precise neural activity driving birdsong production is stable for weeks.

In reinforcement learning (RL) agents are typically tasked with maximizing a single objective function such as reward. But it remains poorly understood how agents might pursue distinct objectives at once. In machines, multiobjective RL can be achieved by dividing a single agent into multiple sub-agents, each of which is shaped by agent-specific rei...

Motor circuits vary in topographic organization, ranging from a coarse relationship between neuron location and function to highly localized regions controlling specific behaviors. For unclear reasons, vocal learning circuits lie at this second extreme: they repeatedly evolved to be spatially segregated from other parts of the motor system. Here we...

Birds of a feather sing together How do birds know that a song that they hear is from a member of their own species, and how do they learn their songs in the first place? Araki et al. identified two types of brain cells involved in how finches learn their songs (see the Perspective by Tchernichovski and Lipkind). When zebra finches were raised by B...