The role of hippocampus during observational learning

Mapping Intimacies ◽

10.1101/832758 ◽

2019 ◽

Author(s):

Yerko Fuentealba ◽

José L Valdés

Keyword(s):

Observational Learning ◽

Critical Role ◽

Memory Task ◽

Pyramidal Cells ◽

Learning Task ◽

Behavioral Performance ◽

Reversible Inactivation ◽

Goal Directed Behavior ◽

Spatial Learning Task

ABSTRACTObservational learning is a fundamental cognitive ability present in several species, where a naïve animal imitates a goal-directed behavior from the observation of a congener which acts as a demonstrator. Recent evidence in bat and rats suggests that hippocampal place cells of an observer may generate a spatial representation of the locations visited by a demonstrator, during spatial navigation. However, it is still unclear whether this hippocampal neural activity is critical for the process of observational learning or if the patterns of activity during observation differ from those emerging from the execution of a spatial memory task previously observed. To test this idea, we assess the role of the hippocampus by pharmacological reversible inactivation during the observation of a spatial learning task, demonstrating a critical role for this structure in observational learning. Then we recorded the neuronal activity of principal pyramidal cells of the same animal when it was observing or solving the memory task, and two different representation of the space emerged after observation or navigation. This evidences demonstrated that the hippocampus is necessary for observational learning and indicated that the observed and executed hippocampal representation are different, confirming the idea that the hippocampus could represent the position of others in the space, and use this information to improve his behavioral performance.

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Value-related neuronal responses in the human amygdala during observational learning

10.1101/865568 ◽

2019 ◽

Author(s):

Tomas G. Aquino ◽

Juri Minxha ◽

Simon Dunne ◽

Ian B. Ross ◽

Adam N. Mamelak ◽

...

Keyword(s):

Social Cognition ◽

Observational Learning ◽

Single Neuron ◽

Population Level ◽

Learning Task ◽

Neuronal Responses ◽

Neurosurgical Patients ◽

Measured Activity ◽

Value Coding

AbstractThe amygdala plays an important role in many aspects of social-cognition and reward-learning. Here we aimed to determine whether human amygdala neurons are involved in the computations necessary to implement learning through observation. We performed single-neuron recordings from the amygdalae of human neurosurgical patients (male and female) while they learned about the value of stimuli through observing the outcomes experienced by another agent interacting with those stimuli. We used a detailed computational modeling approach to describe patients’ behavior in the task. Then, using both population-level decoding and single neuron analyses we found evidence to implicate amygdala neurons in two key computations relevant for observational-learning: tracking the expected future reward associated with a given stimulus, and in tracking outcome values received by oneself or other agents. Encoding and decoding analyses suggested observational value coding in amygdala neurons occurred in a different subset of neurons than experiential value coding. Collectively, these findings support a key role for the human amygdala in the computations underlying the capacity for learning through observation.Significance statementSingle neuron studies of the human brain provide a unique window into the computational mechanisms of cognition. In this study, epilepsy patients implanted intracranially with depth microelectrodes performed an observational learning task. We measured activity bilaterally in the amygdala and found a representation for observational rewards as well as observational expected reward values. Additionally, the representation of self-experienced and observational values was performed by distinct subsets of amygdala neurons. This study thus provides a rare glimpse into the role of human amygdala neurons in social cognition.

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The functional role of sequentially neuromodulated synaptic plasticity in behavioural learning

PLoS Computational Biology ◽

10.1371/journal.pcbi.1009017 ◽

2021 ◽

Vol 17 (6) ◽

pp. e1009017

Author(s):

Grace Wan Yu Ang ◽

Clara S. Tang ◽

Y. Audrey Hay ◽

Sara Zannone ◽

Ole Paulsen ◽

...

Keyword(s):

Reversal Learning ◽

Cholinergic Neurons ◽

Learning Rule ◽

Computational Prediction ◽

Learning Task ◽

Spike Timing ◽

Weight Changes ◽

Experimental Findings ◽

Spatial Learning Task

To survive, animals have to quickly modify their behaviour when the reward changes. The internal representations responsible for this are updated through synaptic weight changes, mediated by certain neuromodulators conveying feedback from the environment. In previous experiments, we discovered a form of hippocampal Spike-Timing-Dependent-Plasticity (STDP) that is sequentially modulated by acetylcholine and dopamine. Acetylcholine facilitates synaptic depression, while dopamine retroactively converts the depression into potentiation. When these experimental findings were implemented as a learning rule in a computational model, our simulations showed that cholinergic-facilitated depression is important for reversal learning. In the present study, we tested the model’s prediction by optogenetically inactivating cholinergic neurons in mice during a hippocampus-dependent spatial learning task with changing rewards. We found that reversal learning, but not initial place learning, was impaired, verifying our computational prediction that acetylcholine-modulated plasticity promotes the unlearning of old reward locations. Further, differences in neuromodulator concentrations in the model captured mouse-by-mouse performance variability in the optogenetic experiments. Our line of work sheds light on how neuromodulators enable the learning of new contingencies.

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Dynamic encoding of saccade sequences in primate frontal eye field

10.1101/2020.08.01.232488 ◽

2020 ◽

Author(s):

Jing Jia ◽

Zhen Puyang ◽

Qingjun Wang ◽

Xin Jin ◽

Aihua Chen

Keyword(s):

Critical Role ◽

Frontal Eye Field ◽

List Type ◽

Sequence Structure ◽

Reversible Inactivation ◽

Eye Field ◽

Saccade Direction ◽

Context Dependent

AbstractFrontal eye field (FEF) is a key part of oculomotor system, with dominant responses to the direction of single saccades. However, whether and how FEF contributes to sequential saccades remain largely unknown. Here by training rhesus monkeys to perform sequential saccades and recording the neuronal activities in FEF, we found that the sequence-related activities are clearly represented in FEF, and many neurons’ selectivity to saccade direction undergoes dynamic changes during sequential task. In addition, the sequence-related activities are context-dependent, with different firing activities during memory- versus visually-guided sequence. Supra-threshold microstimulation in FEF evokes saccade without altering the overall sequence structure. Pharmacological inactivation of FEF severely impaired the monkey’s performance of sequential saccades, with different effects on the same actions at different positions within the sequence. These results reveal the context-dependent dynamic encoding of saccade direction in FEF, and underscore a critical role of FEF in planning and execution of sequential saccades.In BriefJia, Puyang et al. employed in vivo recording to reveal the dynamic encoding of sequential saccades in primate frontal eye field (FEF), then used electric microstimulation and reversible inactivation to demonstrate the causal role of FEF in controlling saccade sequences.HighlightsFEF neurons respond differently during sequential vs. single saccadesSequence-related FEF activity is context-dependentFEF microstimulation induced saccade without altering sequence structureFEF inactivation severely impaired the performance of sequential saccades

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Variability in locomotor dynamics reveals the critical role of feedback in task control

eLife ◽

10.7554/elife.51219 ◽

2020 ◽

Vol 9 ◽

Cited By ~ 1

Author(s):

Ismail Uyanik ◽

Shahin Sefati ◽

Sarah A Stamper ◽

Kyoung-A Cho ◽

M Mert Ankarali ◽

...

Keyword(s):

System Dynamics ◽

Closed Loop ◽

Critical Role ◽

Tracking Task ◽

Behavioral Performance ◽

Task Control ◽

Neural Controllers ◽

Eigenmannia Virescens ◽

The Impact

Animals vary considerably in size, shape, and physiological features across individuals, but yet achieve remarkably similar behavioral performances. We examined how animals compensate for morphophysiological variation by measuring the system dynamics of individual knifefish (Eigenmannia virescens) in a refuge tracking task. Kinematic measurements of Eigenmannia were used to generate individualized estimates of each fish’s locomotor plant and controller, revealing substantial variability between fish. To test the impact of this variability on behavioral performance, these models were used to perform simulated ‘brain transplants’—computationally swapping controllers and plants between individuals. We found that simulated closed-loop performance was robust to mismatch between plant and controller. This suggests that animals rely on feedback rather than precisely tuned neural controllers to compensate for morphophysiological variability.

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Variability in Locomotor Dynamics Reveals the Critical Role of Feedback in Task Control

10.1101/764621 ◽

2019 ◽

Author(s):

Ismail Uyanik ◽

Shahin Sefati ◽

Sarah A. Stamper ◽

Kyoung-A Cho ◽

M. Mert Ankarali ◽

...

Keyword(s):

System Dynamics ◽

Closed Loop ◽

Critical Role ◽

Tracking Task ◽

Behavioral Performance ◽

Task Control ◽

Neural Controllers ◽

Eigenmannia Virescens ◽

The Impact

AbstractAnimals vary considerably in size, shape, and physiological features across individuals, but yet achieve behavioral performances that are virtually indistinguishable between conspecifics. We examined how animals compensate for morphophysiological variation by measuring the system dynamics of individual knifefish (Eigenmannia virescens) in a refuge tracking task. Kinematic measurements of Eigenmannia were used to generate individualized estimates of each fish’s locomotor plant and controller revealing substantial variability between fish. To test the impact of this variability on behavioral performance, these models were used to perform simulated ‘brain transplants’—computationally swapping controllers and plants between individuals. We found that simulated closed-loop performance was robust to mismatch between plant and controller. This suggests that animals rely on feedback rather than precisely tuned neural controllers to compensate for morphophysiological variability.

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The Role of the SLP in Autism Spectrum Disorder Screening and Assessment

Perspectives on Language Learning and Education ◽

10.1044/lle15.2.50 ◽

2008 ◽

Vol 15 (2) ◽

pp. 50-59 ◽

Cited By ~ 1

Author(s):

Amy Philofsky

Keyword(s):

Language Development ◽

Critical Role ◽

Children With Autism ◽

Autism Spectrum ◽

Children With Asd ◽

Prevalence Estimates ◽

Notable Increase ◽

Screening Assessment ◽

Critical Components

AbstractRecent prevalence estimates for autism have been alarming as a function of the notable increase. Speech-language pathologists play a critical role in screening, assessment and intervention for children with autism. This article reviews signs that may be indicative of autism at different stages of language development, and discusses the importance of several psychometric properties—sensitivity and specificity—in utilizing screening measures for children with autism. Critical components of assessment for children with autism are reviewed. This article concludes with examples of intervention targets for children with ASD at various levels of language development.

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