
Contents
-
-
-
-
-
-
-
-
-
5.1 Nonlinear Interaction among Excitation and Inhibition 5.1 Nonlinear Interaction among Excitation and Inhibition
-
5.1.1 Absolute versus Relative Suppression 5.1.1 Absolute versus Relative Suppression
-
5.1.2 General Analysis of Synaptic Interaction in a Passive Tree 5.1.2 General Analysis of Synaptic Interaction in a Passive Tree
-
5.1.3 Location of the Inhibitory Synapse 5.1.3 Location of the Inhibitory Synapse
-
5.1.4 Shunting Inhibition Implements a “Dirty” Multiplication 5.1.4 Shunting Inhibition Implements a “Dirty” Multiplication
-
Effectiveness of Shunting Inhibition Effectiveness of Shunting Inhibition
-
Temporal Specificity Temporal Specificity
-
-
5.1.5 Hyperpolarizing Inhibition Acts Like a Linear Subtraction 5.1.5 Hyperpolarizing Inhibition Acts Like a Linear Subtraction
-
5.1.6 Functional Interpretation of the Synaptic Architecture and Dendritic Morphology: AND-NOT Gates 5.1.6 Functional Interpretation of the Synaptic Architecture and Dendritic Morphology: AND-NOT Gates
-
5.1.7 Retinal Directional Selectivity and Synaptic Logic 5.1.7 Retinal Directional Selectivity and Synaptic Logic
-
-
5.2 Nonlinear Interaction among Excitatory Synapses 5.2 Nonlinear Interaction among Excitatory Synapses
-
5.2.1 Sensitivity of Synaptic Input to Spatial Clustering 5.2.1 Sensitivity of Synaptic Input to Spatial Clustering
-
5.2.2 Cluster Sensitivity for Pattern Discrimination 5.2.2 Cluster Sensitivity for Pattern Discrimination
-
5.2.3 Detecting Coincident Input from the Two Ears 5.2.3 Detecting Coincident Input from the Two Ears
-
-
5.3 Synaptic Microcircuits 5.3 Synaptic Microcircuits
-
5.4 Recapitulation 5.4 Recapitulation
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
1175 Synaptic Interactions In A Passive Dendritic Tree
Get access-
Published:November 1998
Cite
Abstract
Nerve cells are the targets of many thousands of excitatory and inhibitory synapses. An extreme case are the Purkinje cells in the primate cerebellum, which receive between one and two hundred thousand synapses onto dendritic spines from an equal number of parallel fibers (Braitenberg and Atwood, 1958; Llinas and Walton, 1998). In fact, this structure has a crystalline-like quality to it, with each parallel fiber making exactly one synapse onto a spine of a Purkinje cell. For neocortical pyramidal cells, the total number of afferent synapses is about an order of magnitude lower (Larkman, 1991). These numbers need to be compared against the connectivity in the central processing unit (CPU) of modern computers, where the gate of a typical transistor usually receives input from one, two, or three other transistors or connects to one, two, or three other transistor gates. The large number of synapses converging onto a single cell provide the nervous system with a rich substratum for implementing a very large class of linear and nonlinear neuronal operations. As we discussed in the introductory chapter, it is only these latter ones, such as multiplication or a threshold operation, which are responsible for “computing” in the nontrivial sense of information processing. It therefore becomes crucial to study the nature of the interaction among two or more synaptic inputs located in the dendritic tree. Here, we restrict ourselves to passive dendritic trees, that is, to dendrites that do not contain voltage-dependent membrane conductances. While such an assumption seemed reasonable 20 or even 10 years ago, we now know that the dendritic trees of many, if not most, cells contain significant nonlinearities, including the ability to generate fast or slow all-or-none electrical events, so-called dendritic spikes. Indeed, truly passive dendrites may be the exception rather than the rule in the nervous In Sec. 1.5, we studied this interaction for the membrane patch model. With the addition of the dendritic tree, the nervous system has many more degrees of freedom to make use of, and the strength of the interaction depends on the relative spatial positioning, as we will see now. That this can be put to good use by the nervous system is shown by the following experimental observation and simple model.
Sign in
Personal account
- Sign in with email/username & password
- Get email alerts
- Save searches
- Purchase content
- Activate your purchase/trial code
- Add your ORCID iD
Purchase
Our books are available by subscription or purchase to libraries and institutions.
Purchasing informationMonth: | Total Views: |
---|---|
October 2022 | 3 |
November 2022 | 1 |
April 2023 | 4 |
May 2023 | 3 |
June 2023 | 2 |
August 2023 | 3 |
October 2023 | 2 |
January 2024 | 4 |
March 2024 | 1 |
April 2024 | 1 |
May 2024 | 1 |
June 2024 | 5 |
August 2024 | 1 |
October 2024 | 5 |
December 2024 | 6 |
January 2025 | 3 |
February 2025 | 7 |
March 2025 | 2 |
April 2025 | 4 |
Get help with access
Institutional access
Access to content on Oxford Academic is often provided through institutional subscriptions and purchases. If you are a member of an institution with an active account, you may be able to access content in one of the following ways:
IP based access
Typically, access is provided across an institutional network to a range of IP addresses. This authentication occurs automatically, and it is not possible to sign out of an IP authenticated account.
Sign in through your institution
Choose this option to get remote access when outside your institution. Shibboleth/Open Athens technology is used to provide single sign-on between your institution’s website and Oxford Academic.
If your institution is not listed or you cannot sign in to your institution’s website, please contact your librarian or administrator.
Sign in with a library card
Enter your library card number to sign in. If you cannot sign in, please contact your librarian.
Society Members
Society member access to a journal is achieved in one of the following ways:
Sign in through society site
Many societies offer single sign-on between the society website and Oxford Academic. If you see ‘Sign in through society site’ in the sign in pane within a journal:
If you do not have a society account or have forgotten your username or password, please contact your society.
Sign in using a personal account
Some societies use Oxford Academic personal accounts to provide access to their members. See below.
Personal account
A personal account can be used to get email alerts, save searches, purchase content, and activate subscriptions.
Some societies use Oxford Academic personal accounts to provide access to their members.
Viewing your signed in accounts
Click the account icon in the top right to:
Signed in but can't access content
Oxford Academic is home to a wide variety of products. The institutional subscription may not cover the content that you are trying to access. If you believe you should have access to that content, please contact your librarian.
Institutional account management
For librarians and administrators, your personal account also provides access to institutional account management. Here you will find options to view and activate subscriptions, manage institutional settings and access options, access usage statistics, and more.