diff --git a/src/schema/objects/extensions.yaml b/src/schema/objects/extensions.yaml
index 1a0dc4d299..6c678d5149 100644
--- a/src/schema/objects/extensions.yaml
+++ b/src/schema/objects/extensions.yaml
@@ -187,6 +187,11 @@ niigz:
   display_name: Compressed NIfTI
   description: |
     A compressed Neuroimaging Informatics Technology Initiative (NIfTI) data file.
+nix:
+  value: .nix
+  display_name: Neuroscience Information Exchange Format
+  description: |
+    A [Neuroscience Information Exchange](https://nixio.readthedocs.io) file.
 nwb:
   value: .nwb
   display_name: Neurodata Without Borders Format
diff --git a/src/schema/objects/modalities.yaml b/src/schema/objects/modalities.yaml
index 16c7d5474d..e6bdb16965 100644
--- a/src/schema/objects/modalities.yaml
+++ b/src/schema/objects/modalities.yaml
@@ -31,3 +31,6 @@ micr:
 nirs:
   display_name: Near-Infrared Spectroscopy
   description: Data acquired with NIRS.
+ephys:
+  display_name: Electrophysiology
+  description: Data acquired using microelectrodes.
diff --git a/src/schema/objects/suffixes.yaml b/src/schema/objects/suffixes.yaml
index 9e5a41b966..e4a093d066 100644
--- a/src/schema/objects/suffixes.yaml
+++ b/src/schema/objects/suffixes.yaml
@@ -579,6 +579,11 @@ electrodes:
   display_name: Electrodes
   description: |
     File that gives the location of (i)EEG electrodes.
+ephys:
+  value: ephys
+  display_name: Electrophysiology
+  description: |
+    Extra- or intracellular microelectrode recording data.
 epi:
   value: epi
   display_name: EPI
@@ -730,6 +735,11 @@ physio:
   display_name: Physiological recording
   description: |
     Physiological recordings such as cardiac and respiratory signals.
+probe:
+  value: probe
+  display_name: A recording probe
+  description: |
+    A probe with one or more recording contacts.
 probseg:
   value: probseg
   display_name: Probabilistic Segmentation