Memory engrams: Recalling the past and imagining the future

Science, Год журнала: 2020, Номер 367(6473)

Опубликована: Янв. 3, 2020

In 1904, Richard Semon introduced the term "engram" to describe neural substrate for storing memories. An experience, proposed, activates a subset of cells that undergo off-line, persistent chemical and/or physical changes become an engram. Subsequent reactivation this engram induces memory retrieval. Although Semon's contributions were largely ignored in his lifetime, new technologies allow researchers image and manipulate brain at level individual neurons has reinvigorated research. We review recent progress studying engrams, including evaluation evidence existence importance intrinsic excitability synaptic plasticity lifetime Together, these findings are beginning define as basic unit memory.

Язык: Английский

---

The connectome of the adult Drosophila mushroom body provides insights into function

eLife, Год журнала: 2020, Номер 9

Опубликована: Дек. 14, 2020

Making inferences about the computations performed by neuronal circuits from synapse-level connectivity maps is an emerging opportunity in neuroscience. The mushroom body (MB) well positioned for developing and testing such approach due to its conserved architecture, recently completed dense connectome, extensive prior experimental studies of roles learning, memory, activity regulation. Here, we identify new components MB circuit Drosophila, including visual input output neurons (MBONs) with direct connections descending neurons. We find unexpected structure sensory inputs, transfer information different modalities MBONs, modulation that dopaminergic (DANs). provide insights into circuitry used integrate outputs, between central complex inputs DANs, feedback MBONs. Our results a foundation further theoretical work.

Язык: Английский

---

Behavioral and neurobiological mechanisms of pavlovian and instrumental extinction learning

Physiological Reviews, Год журнала: 2020, Номер 101(2), С. 611 - 681

Опубликована: Сен. 24, 2020

This article reviews the behavioral neuroscience of extinction, phenomenon in which a behavior that has been acquired through Pavlovian or instrumental (operant) learning decreases strength when outcome reinforced it is removed. Behavioral research indicates neither nor operant extinction depends substantially on erasure original but instead new inhibitory primarily expressed context learned, as exemplified by renewal effect. Although nature inhibition may differ and either case decline responding depend both generalization decrement correction prediction error. At neural level, requires tripartite circuit involving amygdala, prefrontal cortex, hippocampus. Synaptic plasticity amygdala essential for learning, cortical neurons encoding fear memories involved retrieval. Hippocampal-prefrontal circuits mediate relapse phenomena, including renewal. Instrumental involves distinct ensembles corticostriatal, striatopallidal, striatohypothalamic well their thalamic returns (extinction) excitatory (renewal other phenomena) control over responding. The field made significant progress recent decades, although fully integrated biobehavioral understanding still awaits.

Язык: Английский

---

FlyWire: online community for whole-brain connectomics

Nature Methods, Год журнала: 2021, Номер 19(1), С. 119 - 128

Опубликована: Дек. 23, 2021

Язык: Английский

---

Distinct Dopamine Receptor Pathways Underlie the Temporal Sensitivity of Associative Learning

Cell, Год журнала: 2019, Номер 178(1), С. 60 - 75.e19

Опубликована: Июнь 1, 2019

Язык: Английский

---

The natverse, a versatile toolbox for combining and analysing neuroanatomical data

eLife, Год журнала: 2020, Номер 9

Опубликована: Апрель 14, 2020

To analyse neuron data at scale, neuroscientists expend substantial effort reading documentation, installing dependencies and moving between analysis visualisation environments. facilitate this, we have developed a suite of interoperable open-source R packages called the natverse. The natverse allows users to read local remote data, perform popular analyses including clustering graph-theoretic neuronal branching. Unlike most tools, enables comparison across many neurons morphology connectivity after imaging or co-registration within common template space. also transformations different spaces modalities. We demonstrate tools that integrate vast majority

Язык: Английский

---

Amygdala Reward Neurons Form and Store Fear Extinction Memory

Neuron, Год журнала: 2020, Номер 105(6), С. 1077 - 1093.e7

Опубликована: Янв. 14, 2020

Язык: Английский

---

The Drosophila Mushroom Body: From Architecture to Algorithm in a Learning Circuit

Annual Review of Neuroscience, Год журнала: 2020, Номер 43(1), С. 465 - 484

Опубликована: Апрель 14, 2020

The Drosophila brain contains a relatively simple circuit for forming Pavlovian associations, yet it achieves many operations common across memory systems. Recent advances have established clear framework learning and revealed the following key operations: a) pattern separation, whereby dense combinatorial representations of odors are preprocessed to generate highly specific, nonoverlapping odor patterns used learning; b) convergence, in which sensory information is funneled small set output neurons that guide behavioral actions; c) plasticity, where changing mapping input requires strong reinforcement signal, also modulated by internal state environmental context; d) modularization, consists multiple parallel traces, distinct stability flexibility exist anatomically well-defined modules within network. Cross-module interactions allow higher-order effects past experience influences future learning. Many these parallels with processes formation action selection more complex brains.

Язык: Английский

---

Dopamine neurons drive fear extinction learning by signaling the omission of expected aversive outcomes

eLife, Год журнала: 2018, Номер 7

Опубликована: Ноя. 13, 2018

Extinction of fear responses is critical for adaptive behavior and deficits in this form safety learning are hallmark anxiety disorders. However, the neuronal mechanisms that initiate extinction largely unknown. Here we show, using single-unit electrophysiology cell-type specific fiber photometry, dopamine neurons ventral tegmental area (VTA) activated by omission aversive unconditioned stimulus (US) during extinction. This signal occurred specifically beginning when US unexpected, correlated strongly with learning. Furthermore, temporally-specific optogenetic inhibition or excitation at time revealed both necessary for, sufficient to accelerate, normal These results identify a prediction error-like reveal crucial role DA

Язык: Английский

---

Recurrent architecture for adaptive regulation of learning in the insect brain

Nature Neuroscience, Год журнала: 2020, Номер 23(4), С. 544 - 555

Опубликована: Март 23, 2020

Язык: Английский

---