Photodiode array systems have been used to
make the following recordings:
|Page display and multi-frame pseudocolor display of a control response (a) and epileptic activity (b) in brain slices. a) A control slice of piriform cortex stimulated in layer Ib at 400 mA (single trial). |
b) An epileptogenic slice stimulated in layer II at 275 mA (single trial). Each multi-frame display shows images at 3.8 msec intervals. Note the large secondary response in the epileptogenic slice. In this experiment the site of onset was the dorsal edge of the En. Epileptiform activity which originated at this site spread to the overlying piriform cortex and the neighboring AI/PRha.
Provided by Rezan Demir and Meyer Jackson , University of Wisconsin
|Enlargement of B (top) in the figure above. |
Each trace is 967 msec in duration.
|Responses evoked by electrical stimulation of dentate gyrus in a hippocampal slice (frame interval = 2 msec)|
Provided by Pavel Balaban, Institute of Higher Nervous Activity, Moscow.
|Multi-frame pseudocolor display (8 msec/frame) of the oscillatory responses to odorant in the turtle olfactory bulb. The signal on the right (rostral bulb) has a frequency twice that of the signal on the left (caudal bulb). |
For Trace display ; for Page display .
Provided by Yin-wan Lam, Larry Cohen, Michal Zockowski, Yale University. (J Neuroscience 20:749-762, 2000)
| Initiation of epileptiform activity in brain slice preparations with experimentally induced focal cortical malformations. Epileptiform activity (0 Mg2+) from brain slices (500 ? m) of adult rats with focal cortical malformations (microgyrus, cf. Redecker et al., J. Neurosci., 2000, 20:5045-53) was monitored using conventional field potential recordings and optical imaging of membrane potential (VSD RH795). The movie shows both the epileptic field potential and the corresponding optical signal. The positions of the field potential electrode and the optical frame are projected onto the original histology of the slice.|
Note that the initiation site of epileptiform activity (focus) is located in the dysplastic cortex and that there is ongoing activity even after the decay of the epileptiform field potential.
Click here to view movie.
The movie is quite large (185KB), so it may be slow on a dial up connection.
Provided by Christoph Redecker, Paul Boerrigter, Georg Hagemann, Erwin-Josef Speckmann et al. (Redecker et al., Soc. Neurosci. Abs., 27: 757.5, 2001)
|Spontaneous activity from a ganglion of the submucous plexus in guinea pig small intestine. |
Provided by Ana Lia Obaid, Tetsuro Sakai & Brian Salzberg, University of Pennsylvania. (J Neuroscience, 19: 3073-3093, 1999)
|Di-8-ANEPPS labelled enteric ganglion, submucosal plexus. |
A - Di-8-ANEPPS labeled enteric ganglion, submucosal plexus.
B & C - Synaptic activation after single pulse fiber tract stimulation; fast EPSP triggered action potentials (left panels) as well as subthreshold fast EPSPs (right panels) are shown. Note that the remaining fast EPSP in the intracellular recording is clearly present in the optical recording.
D & E- Response to a depolarizing current pulse (D and E) and
F & G- one expanded action potential (F and G).
H & I- Slow EPSP associated increase in spike discharge. Note that a previously subthreshold current pulse evokes multiple action potentials after fiber tract stimulation (20Hz, 1.5s, indicated by).
Provided by Michael Schemann, Department of Human Biology, Technical University of Munich, Germany. (Neurogastroenterol Motil., 11: 393-402, 1999)
|Action potential signals from individual neurons stained with an absorption dye. Response to a siphon touch in an Aplysia abdominal ganglion. |
Provided by Chun X. Falk , Yale University. (J. Neuroscience, 14: 4167-4184, 1994)