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. 2016 Dec 8;11(12):e0166598. doi: 10.1371/journal.pone.0166598

Fig 7. Our algorithm applied to recordings from the human medial temporal lobe (MTL).

Fig 7

A 15 seconds of bandpass filtered data (passband 300 Hz to 1000 Hz) from a micro-electrode in the right anterior hippocampus. Extraction threshold is marked in red. Several artifact events are clearly visible. B This recording channel is extremely noisy: Our pre-sorting artifact detection removed ≈ 77% of all spikes from the recorded data. The pink lines depict the cumulative count of events over the course of the recording (28 minutes). C Cluster sizes at different temperatures. Left panel, input to the first clustering step were all non-artifact spikes. Right panel, input to the second clustering step were residual spikes not assigned to any cluster in the first clustering step. Color code of marked dots as in Fig 3. D Output of our sorting algorithm. Post-sorting artifact detection correctly identified several artifact clusters, but missed one (number 4). Six non-artifact clusters remain. E Result that expert operators generated manually with WaveClus. Two clusters were identified, ≈ 17000 spikes were left unassigned. F Results of the picture presentation experiment. Displayed are raster plots corresponding to Clusters 1 and 2 from D, and to Cluster 1 from E. Responses to four different pictures are shown. It is clearly visible that Cluster D 2 responds sharply to pictures of four male celebrities, while the responses of Cluster E 1 to the second, third and fourth picture are barely recognizable. No other cluster from D responded to any stimulus. S, score of the response; R, rating given to the response by human raters (see main text for details). Stimulus pictures displayed here have been replaced by similar pictures for legal and privacy reasons. Copyright notes: F.1 Photographer: Armin Kübelbeck, CC BY-SA 3.0, Wikimedia Commons (https://commons.wikimedia.org/wiki/File:Campino_02.jpg) F.2 “Mel Gibson at the Cannes film festival” by Georges Biard is licensed under CC BY-SA 3.0, Wikimedia Commons (https://commons.wikimedia.org/wiki/File:Mel_Gibson_2011_cropped.jpg) F.3 cropped from “German actor Jan Josef Liefers at the Cinema for Peace gala” by Thore Siebrands, licensed under CC BY 3.0, ipernity (http://www.ipernity.com/doc/siebbi/10852332) F.4 cropped from “Letztes Training von Olli Kahn beim FC Bayern München” by Dirk Vorderstraße, licensed under CC BY 2.0, Flickr (https://www.flickr.com/photos/dirkvorderstrasse/10560731386).