Related Experiment Video
Updated: Jul 11, 2026
26:41
Perspectives on Neuroscience
Published on: July 31, 2007
The place of 'codes' in nonlinear neurodynamics
1Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720-3206, USA. dfreeman@berkeley.edu
Progress in Brain Research
|October 11, 2007
Summary
Cognitive science explores how brains translate sensory input into abstract concepts using neural codes. This review examines materialist, cognitivist, and dynamist approaches, using olfaction as a model.
Area of Science:
- Cognitive Science
- Neuroscience
- Computational Neuroscience
Background:
- Explaining the neural basis of abstract concept formation from sensory stimuli is a central challenge.
- Understanding the transition from specific stimulus energy to generic concepts requires examining neural coding mechanisms.
Purpose of the Study:
- To review and compare three major approaches to neural coding: materialist, cognitivist, and dynamist.
- To use olfaction as a paradigm to illustrate how neural codes mediate diverse brain functions from sensation to action.
Main Methods:
- Analysis of materialist approaches focusing on rate and frequency codes in action potentials.
- Examination of cognitivist approaches involving symbolic codes and hierarchical feature detection.
- Review of dynamist approaches utilizing oscillatory fields and chaotic attractors in brain state space.
Main Results:
- Neural codes lack the alphabet and syntax of systems like DNA or the periodic table.
- These codes function as epistemological metaphors for experimental measurement and engineering models.
- Olfaction serves as a model system for understanding how neural codes generate cortical activities.
Conclusions:
- Neural codes are crucial for bridging sensory input and abstract conceptualization.
- Different coding strategies (rate, symbolic, dynamic) offer distinct perspectives on brain function.
- The study of olfaction provides insights into the neural mechanisms underlying sensation, perception, and action.
Related Concept Videos
01:25Neural Circuits
Neural circuits and neuronal pools are two of the main structures found in the nervous system. Neural circuits are networks of neurons that work together to carry out a specific task or process. They consist of interconnected neurons and glial cells, which provide structural and metabolic support.
Neuronal pools are collections of nerve cells with similar functions and interact through chemical and electrical signals. These pools include both interneurons (the central neural circuit nodes that...
Neuronal pools are collections of nerve cells with similar functions and interact through chemical and electrical signals. These pools include both interneurons (the central neural circuit nodes that...
01:28Neuronal Communication
Neurons, the fundamental units of the brain and nervous system, communicate through complex electrochemical signals that underpin all cognitive and bodily functions. This communication is primarily facilitated by a process involving the generation and propagation of an action potential along the axon of the neuron. When the internal electrical charge of a neuron surpasses a certain threshold, an action potential is triggered. This rapid change in voltage travels swiftly along the axon to the...
01:23Propagation of Action Potentials
The propagation of an action potential refers to the process by which a nerve impulse, or "action potential," travels along a neuron.
Neurons (nerve cells) have a resting membrane potential, with a slightly negative charge inside compared to outside. This is maintained by ion channels, such as sodium (Na+) and potassium (K+) channels, which control the flow of ions. When a stimulus, like a touch or a signal from another neuron, triggers the neuron, sodium channels open, allowing sodium ions to...
Neurons (nerve cells) have a resting membrane potential, with a slightly negative charge inside compared to outside. This is maintained by ion channels, such as sodium (Na+) and potassium (K+) channels, which control the flow of ions. When a stimulus, like a touch or a signal from another neuron, triggers the neuron, sodium channels open, allowing sodium ions to...
01:19The Role of Ion Channels in Neuronal Computation
A postsynaptic neuron usually receives numerous impulses from several other presynaptic neurons. The axon hillock of the postsynaptic neuron integrates all these signals and determines the likelihood of firing an action potential.
Sometimes a single EPSP is strong enough to induce an action potential in the postsynaptic neuron. However, multiple presynaptic inputs must often create EPSPs around the same time for the postsynaptic neuron to be sufficiently depolarized to fire an action potential.
Sometimes a single EPSP is strong enough to induce an action potential in the postsynaptic neuron. However, multiple presynaptic inputs must often create EPSPs around the same time for the postsynaptic neuron to be sufficiently depolarized to fire an action potential.
01:22Neurons as Communicators of the Brain
Neurons, the fundamental units of the brain and nervous system, function as the primary transmitters of information throughout the body. Their ability to communicate through electrical and chemical signals is vital for every bodily function, from regulating the heartbeat to processing complex thoughts. Each neuron has three main components: the cell body (soma), dendrites, and an axon, each specialized to facilitate swift and efficient neural communication.
Cell Body
The cell body, also known...
Cell Body
The cell body, also known...
01:26Classification of Systems-I
Linearity is a system property characterized by a direct input-output relationship, combining homogeneity and additivity.
Homogeneity dictates that if an input x(t) is multiplied by a constant c, the output y(t) is multiplied by the same constant. Mathematically, this is expressed as:
Homogeneity dictates that if an input x(t) is multiplied by a constant c, the output y(t) is multiplied by the same constant. Mathematically, this is expressed as: