Related Experiment Video
Updated: Jun 15, 2026
09:07
Fluorescent Calcium Imaging and Subsequent In Situ Hybridization for Neuronal Precursor Characterization in Xenopus laevis
Published on: February 18, 2020
Calcium dynamics encode the magnitude of a graded memory underlying sensorimotor adaptation
Nikolai C Dembrow1, Diana L Pettit, Harold H Zakon
1Center for Learning and Memory, University of Texas at Austin, Austin, TX 78712-0805, USA. nikolai@mail.clm.utexas.edu
Journal of Neurophysiology
|February 26, 2010
Summary
Calcium dynamics (Ca2+) encode the strength of sensorimotor adaptation memory in electric fish. This cellular mechanism explains how graded memory magnitude is encoded, challenging binary views of memory formation.
Area of Science:
- Neuroscience
- Animal Behavior
- Cellular Biology
Background:
- Memory formation is often viewed simplistically, yet many memories exhibit graded strength and persistence.
- The precise role of calcium ions (Ca2+) in encoding these nuanced memory characteristics remains incompletely understood.
Purpose of the Study:
- To investigate how Ca2+ dynamics encode the magnitude of sensorimotor adaptation in weakly electric fish.
- To explore the cellular mechanisms underlying graded memory formation.
Main Methods:
- Electrophysiological recordings in weakly electric fish to monitor neural activity and Ca2+ dynamics.
- Analysis of sensorimotor adaptation in electromotor output following various stimuli.
Main Results:
- Ca2+ dynamics were found to accurately encode the magnitude of sensorimotor adaptation.
- A synaptically induced, Ca2+-dependent enhancement of neuronal intrinsic excitability was identified as the neural correlate of this graded memory.
- The observed changes in Ca2+ predicted memory magnitude across a range of stimulus intensities.
Conclusions:
- Ca2+ dynamics play a crucial role in encoding the graded magnitude of sensorimotor memory.
- A straightforward cellular mechanism involving enhanced neuronal excitability can mediate graded memory over timescales from seconds to minutes.
Related Concept Videos
01:27Feedback Regulation of Calcium Concentration
Calcium is an essential signaling molecule required for various cellular functions. Calcium pumps and ion channels on cell and organellar membranes, such as those on the endoplasmic reticulum (ER), regulate calcium concentrations inside the cell. They remain closed, keeping the cytosolic calcium levels low at a resting state.
Various transmembrane receptors, such as G protein-coupled receptors (GPCRs), elicit a response to extracellular signals by increasing cytosolic calcium. Activated GPCRs...
Various transmembrane receptors, such as G protein-coupled receptors (GPCRs), elicit a response to extracellular signals by increasing cytosolic calcium. Activated GPCRs...
01:16Calmodulin-dependent Signaling
Calmodulin (CaM) is a calcium-binding protein in eukaryotes that controls various calcium-regulated cellular processes. It has four calcium-binding sites that bind calcium to form the calcium-calmodulin ( Ca2+-CaM) complex. GPCR stimulation increases the calcium levels in the cells that bind to CaM and induces a conformational change.
The Ca2+-CaM complex does not have enzymatic activity by itself. Instead, the complex binds downstream target proteins, including membrane proteins or enzymes,...
The Ca2+-CaM complex does not have enzymatic activity by itself. Instead, the complex binds downstream target proteins, including membrane proteins or enzymes,...
01:19Graded Potential
Graded potentials are localized fluctuations in the cell membrane's electrical charge, commonly found in the dendrites of neurons. The magnitude of these potential changes depends on the strength of the initiating stimulus. In a membrane at its resting potential, a graded potential signifies a voltage shift either above -70 mV or below -70 mV.
Graded potentials fall into two categories: depolarizing and hyperpolarizing. Depolarizing graded potentials typically occur when sodium (Na+) or calcium...
Graded potentials fall into two categories: depolarizing and hyperpolarizing. Depolarizing graded potentials typically occur when sodium (Na+) or calcium...
01:21Skeleton and Calcium Homeostasis
Calcium is not only the most abundant mineral in bone but also the most abundant mineral in the human body. Calcium ions are needed for bone mineralization, tooth health, heart rate regulation and strength of contraction, blood coagulation, the contraction of smooth and skeletal muscle cells, and the regulation of nerve impulse conduction. The average calcium level in the blood is about 10 mg/dL. When the body cannot maintain this level, a person will experience hypo or hypercalcemia.
01:03Long-term Depression
Long-term depression, or LTD, is one of the ways by which synaptic plasticity—changes in the strength of chemical synapses—can occur in the brain. LTD is the process of synaptic weakening that occurs over time between pre and postsynaptic neuronal connections. The synaptic weakening of LTD works in opposition to synaptic strengthening by long-term potentiation (LTP) and together are the main mechanisms that underlie learning and memory.
Calcium Ion Concentration Mechanism
If over time, all...
Calcium Ion Concentration Mechanism
If over time, all...