The Radiens Data Model
Covers Study, Experiment, Session, Trial, Subject, Metadata and NWB (Neurodata Without Borders).
Study
Study
The top tier of the Radiens data hierarchy: study ⊃ experiment ⊃ session ⊃ trial. A study is an overarching scientific program comprising one or more experiments.
Study is an organizational concept rather than a first-class Radiens software object — it structures how work is planned and discussed, not a managed entity in the software today.
Experiment
Experiment
The organizational tier between study and session in the Radiens data hierarchy (study ⊃ experiment ⊃ session ⊃ trial). An experiment groups one or more sessions within a study.
Experiment is an organizational concept, not a first-class Radiens software object. In everyday lab usage the word is overloaded — "doing an experiment today" often refers to a single session or recording rather than the formal experiment tier. For that reason, experiment is avoided as a precise term in product specifications.
Session
Session
A recording session: a subject implanted with a probe, and an operator acquiring data with Allego. In the Radiens data hierarchy a session contains one or more trials (study ⊃ experiment ⊃ session ⊃ trial).
Current status: session is loosely defined today — inferred by grouping a subject's trial files by their date and time, rather than managed as a first-class object. A richer, explicitly modeled Session is on the near-term Radiens roadmap.
Trial
Trial
The atomic unit of data collection in Radiens. A trial is one recording — a single Record start-to-stop in Allego — saved as one streaming data file. The terms trial, recording, and data file refer to the same object.
Trial is a first-class Radiens construct. Event-gated analyses such as the peri-stimulus time histogram (PSTH) operate on a trial — accumulating responses live as the trial streams in Allego, or post hoc in Videre.
Subject
Subject
The experimental subject — an animal implanted with a probe — from which data is acquired during a recording session. Colloquially, operators speak of "running an animal."
Subject is the formal register; animal is the common colloquial equivalent.
Metadata
Metadata is descriptive information about recorded neural data — including the subject, recording date, sampling rate, filter settings, hardware configuration, and processing history.
Why it matters: Without complete metadata, neural recordings lose scientific value. Metadata enables reproducibility, proper analysis configuration, data sharing, and long-term archival. It is a cornerstone of FAIR (Findable, Accessible, Interoperable, Reusable) data principles.
Key metadata fields: Subject ID, species, brain region, recording date, sampling rate, headstage type, filter settings, probe configuration, software version, and experimenter.
Software: Radiens Allego captures hardware metadata automatically during acquisition. Radiens tracks processing provenance — the exact sequence of transforms applied to the data.
NWB (Neurodata Without Borders)
NWB (Neurodata Without Borders) is the open standard file format for neurophysiology data. It holds the recording, the electrode geometry, the stimulus and the subject metadata in one file, so a dataset stays interpretable after the software that made it has moved on.
Radiens treats NWB as first class: it opens NWB files natively with no conversion step, and it writes or converts any recording to NWB. That matters at the two ends of a study. At the start, data recorded elsewhere can be read without a translation stage. At the end, a deposit-ready file is a write rather than a project.
The alternative is an acquisition system's own format, which is usually faster to write and harder to read five years later. NWB is the trade in the other direction.
Research use only.