Phase-dependent effects of stimuli locked to oscillatory activity in cultured cortical networks.
Biophys J
; 98(11): 2452-8, 2010 Jun 02.
Article
em En
| MEDLINE
| ID: mdl-20513388
ABSTRACT
The archetypal activity pattern in cultures of dissociated neurons is spontaneous network-wide bursting. Bursts may interfere with controlled activation of synaptic plasticity, but can be suppressed by the application of stimuli at a sufficient rate. We sinusoidally modulated (4 Hz) the pulse rate of random background stimulation (RBS) and found that cultures were more active, burst less frequently, and expressed oscillatory activity. Next, we studied the effect of phase-locked tetani (four pulses, 200 s(-1)) on network activity. Tetani were applied to one electrode at the peak or trough of mRBS stimulation. We found that when tetani were applied at the peak of modulated RBS (mRBS), a significant potentiation of poststimulus histograms (PSTHs) occurred. Conversely, tetani applied at the trough resulted in a small but insignificant depression of PSTHs. In addition to PSTHs, electrode-specific firing rate profiles within spontaneous bursts before and after mRBS were analyzed. Here, significant changes in firing rate profiles were found only for stimulation at the peak of mRBS. Our study shows that rhythmic activity in culture is possible, and that the network responds differentially to strong stimuli depending on the phase at which they are delivered. This suggests that plasticity mechanisms may be differentially accessible in an oscillatory state.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Córtex Cerebral
/
Plasticidade Neuronal
Limite:
Animals
Idioma:
En
Revista:
Biophys J
Ano de publicação:
2010
Tipo de documento:
Article
País de afiliação:
Holanda