Using holographic illumination to study synaptic signal integration at individual dendritic spines

A fundamental problem in taste research is to determine how gustatory signals are processed and disseminated in the mammalian central nervous system. An important first step toward understanding information processing is the identification of cell types in the nucleus of the solitary tract (NST) and their synaptic relationships with oral primary afferent terminals. Facial and glossopharyngeal (LIX) terminals in the hamster were labelled with HRP, examined with EM, and characterized as containing moderate concentrations of medium-sized round vesicles, and engaging in asymmetrical synaptic junctions. Ultrastructurally the endings resemble excitatory synapses in other brain regions.Labelled facial afferent endings in the RC subdivision synapse almost exclusively with distal dendrites and dendritic spines of NST cells. Most synaptic relationships between the facial synapses and the dendrites are simple. However, 40% of facial endings engage in complex synaptic relationships within glomeruli containing unlabelled axon endings particularly ones termed "SP" endings. SP endings are densely packed with small, pleomorphic vesicles and synapse with both the facial endings and their postsynaptic dendrites by means of nearly symmetrical junctions.

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Three-dimensional structure of dendritic spines, neuronal specializations that impart both stability and flexibility to synaptic function

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100146308 ◽

1993 ◽

Vol 51 ◽

pp. 92-93

Author(s):

Kristen M. Harris

Keyword(s):

Dendritic Spines ◽

Three Dimensional ◽

Synaptic Function ◽

Dimensional Structure ◽

Excitatory Synapses ◽

Concept Of Function ◽

Section Electron ◽

High Quality Information ◽

The Central Nervous System ◽

Mathematical Analyses

Dendritic spines are the tiny protrusions that stud the surface of many neurons and they are the location of over 90% of all excitatory synapses that occur in the central nervous system. Their small size and variable shapes has in large part made detailed study of their structure refractory to conventional light microscopy and single section electron microscopy (EM). Yet their widespread occurrence and likely involvement in learning and memory has motivated extensive efforts to obtain quantitative descriptions of spines in both steady state and dynamic conditions. Since the seminal mathematical analyses of D’Arcy Thompson, the power of establishing quantitatively key parameters of structure has become recognized as a foundation of successful biological inquiry. For dendritic spines highly precise determinations of structure and its variation are proving themselves as the kingpin for establishing a valid concept of function. The recent conjunction of high quality information about the structure, function, and theoretical implications of dendritic spines has produced a flurry of new considerations of their role in synaptic transmission.

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Frontiers in Synaptic Plasticity: Dendritic Spines, Circuitries and Behavior

10.3389/978-2-88919-947-1 ◽

2016 ◽

Keyword(s):

Synaptic Plasticity ◽

Dendritic Spines ◽

And Behavior

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Enhanced Detection Sensitivity with Pulsed Laser Digital Signal Integration Algorithm

ISTFA 2006: Conference Proceedings from the 32nd International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2006p0234 ◽

2006 ◽

Author(s):

A.C.T. Quah ◽

J.C.H. Phang ◽

L.S. Koh ◽

S.H. Tan ◽

C.M. Chua

Keyword(s):

Fault Localization ◽

Pulsed Laser ◽

Digital Signal ◽

Detection Sensitivity ◽

Signal Integration ◽

Laser Operation ◽

Frequency Range ◽

Integration Algorithm ◽

Detection Systems ◽

Lock In

Abstract This paper describes a pulsed laser induced digital signal integration algorithm for pulsed laser operation that is compatible with existing ac-coupled and dc-coupled detection systems for fault localization. This algorithm enhances laser induced detection sensitivity without a lock-in amplifier. The best detection sensitivity is achieved at a pulsing frequency range between 500 Hz to 1.5 kHz. Within this frequency range, the algorithm is capable of achieving more than 9 times enhancement in detection sensitivity.

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