[[File:Spike triggered averages.png|alt=Spike-triggered averages|thumb|321x321px|Spike-triggered averages of LFP from 4 recording sites. The spike is the sharp downward deflection at t = 0. The spike is preceded by slow oscillations (alpha), the spike happens at the trough of the LFP.<ref name=":0">{{Cite journal |last=Oostenveld |first=Robert |last2=Fries |first2=Pascal |last3=Maris |first3=Eric |last4=Schoffelen |first4=Jan-Mathijs |date=2011 |title=FieldTrip: Open Source Software for Advanced Analysis of MEG, EEG, and Invasive Electrophysiological Data |url=http://www.hindawi.com/journals/cin/2011/156869/ |journal=Computational Intelligence and Neuroscience |language=en |volume=2011 |pages=1–9 |doi=10.1155/2011/156869 |issn=1687-5265 |pmc=PMC3021840 |pmid=21253357}}</ref>]]
The local field potential is believed to represent the sum of synaptic inputs into the observed area, as opposed to the [[Action potential|spikespikes]] data, which represents the output from the area. In the LFP, high-frequency fluctuations in the potential difference are filtered out, leaving only the slower fluctuations. The fast fluctuations are mostly caused by the short inward and outward currents of action potentials, while the direct contribution of action potentials is minimal in the LFP. The LFP is thus composed of the more sustained currents in the tissue,suchthat asare thegenerated by synaptic activity ([[synapseExcitatory postsynaptic potential|synapticEPSC]]s and somato-[[DendriteInhibitory postsynaptic potential|dendriticIPSC]]s).<ref currentsname="Kamondi 1998">{{cite journal |last=Kamondi |first=A |author2=Acsády, L |author3=Wang, XJ |author4=Buzsáki, G |year=1998 |title=Theta oscillations in somata and dendrites of hippocampal pyramidal cells in vivo: activity-dependent phase-precession of action potentials. |journal=Hippocampus |volume=8 |issue=3 |pages=244–61 |doi=10.1002/(SICI)1098-1063(1998)8:3<244::AID-HIPO7>3.0.CO;2-J |pmid=9662139 |s2cid=10021185}}</ref> Data-driven models have shown a predictive relationship between the LFPs and spike activity.<ref name="Michmizos 2012">{{cite journal|last=Michmizos|first=K|author2=Sakas, D |author3=Nikita, K |title=Prediction of the timing and the rhythm of the parkinsonian subthalamic nucleus neural spikes using the local field potentials.|journal=IEEE Transactions on Information Technology in Biomedicine|year=2012|volume=16|issue=2|pages=190–97|doi=10.1109/TITB.2011.2158549|pmid=21642043|s2cid=11537329}}</ref> TheA majorcommon slowmethod currentsto involvedinvestigate inLFP generatingoscillations thethat LFP are believedlead to bespikes theis sameto thatcalculate generatespike-triggered theaverages [[postsynaptic(see potential]] (PSPfigure). ItThis wasis originallydone thoughtafter thatthe [[Excitatoryrecording postsynaptic(off potential|EPSP]]sline) andby [[Inhibitorydetecting postsynapticthe potential|IPSP]]sspikes wereas thefast exclusivedownward constituentsdeflections, ofcutting LFPs,out butthe phenomenatemporal unrelatedsections toaround synapticthe eventsspike were(+/- later250 foundms) toand contribute toaveraging the signalspike-aligned (Kobayashitraces 1997)for each recording site.<ref name="Kamondi:0" 1998"/>{{citejournal|last=Kamondi|first=A|author2=AcsádyAlternatively, Lspikes |author3=Wang,can XJbe |author4=removed Buzsáki,from Gthe |title=Thetaextracellular oscillationsrecording intraces somataby and dendrites of hippocampal pyramidal cells in vivo: activitylow-dependentpass phase-precessionfiltering, ofrevealing actionthe potentialsLFP.|journal=Hippocampus|year=1998|volume=8|issue=3|pages=244–61|doi=10.1002/(SICI)1098-1063(1998)8:3<244::AID-HIPO7>3.0.CO;2-J|pmid=9662139|s2cid=10021185}}</ref>A common method to investigate LFP oscillations that lead to spikes is to calculate spike-triggered averages (see figure).
