CAVE Quickstart

The Connectome Annotation Versioning Engine (CAVE) is a suite of tools developed at the Allen Institute and Seung Lab to manage large connectomics data.

Initial Setup

Before using any programmatic access to the data, you first need to set up your CAVEclient token.

CAVEclient

Most programmatic access to the CAVE services occurs through CAVEclient, a Python client to access various types of data from the online services.

Full documentation for CAVEclient is available here.

To initialize a caveclient, we give it a datastack, which is a name that defines a particular combination of imagery, segmentation, and annotation database. For the MICrONs public data, we use the datastack name minnie65_public.

from caveclient import CAVEclient
datastack_name = 'minnie65_public'
client = CAVEclient(datastack_name)

# Show the description of the datastack
client.info.get_datastack_info()['description']
'This is the publicly released version of the minnie65 volume and segmentation. '

Materialization versions

Data in CAVE is timestamped and periodically versioned - each (materialization) version corresponds to a specific timestamp. Individual versions are made publicly available. The materialization service provides annotation queries to the dataset. It is available under client.materialize.

Periodic updates are made to the public datastack, which will include updates to the available tables. Some cells will have different pt_root_id because they have undergone proofreading.

It is worth checking the version of the data you are using, and specifying the version for analysis consistency.

# see the available materialization versions
client.materialize.get_versions()
[1078, 117, 661, 343, 1181, 795, 943]

And these are their associated timestamps (all timestamps are in UTC):

for version in client.materialize.get_versions():
    print(f"Version {version}: {client.materialize.get_timestamp(version)}")
Version 1078: 2024-06-05 10:10:01.203215+00:00
Version 117: 2021-06-11 08:10:00.215114+00:00
Version 661: 2023-04-06 20:17:09.199182+00:00
Version 343: 2022-02-24 08:10:00.184668+00:00
Version 1181: 2024-09-16 10:10:01.121167+00:00
Version 795: 2023-08-23 08:10:01.404268+00:00
Version 943: 2024-01-22 08:10:01.497934+00:00
# set materialization version, for consistency
materialization = 1181 # current public as of 9/16/2024
client.version = materialization

CAVEclient Basics

The most frequent use of the CAVEclient is to query the database for annotations like synapses. All database functions are under the client.materialize property. To see what tables are available, use the get_tables function:

client.materialize.get_tables()
['nucleus_alternative_points',
 'allen_column_mtypes_v2',
 'bodor_pt_cells',
 'aibs_metamodel_mtypes_v661_v2',
 'allen_v1_column_types_slanted_ref',
 'aibs_column_nonneuronal_ref',
 'nucleus_ref_neuron_svm',
 'apl_functional_coreg_vess_fwd',
 'vortex_compartment_targets',
 'baylor_log_reg_cell_type_coarse_v1',
 'functional_properties_v3_bcm',
 'l5et_column',
 'pt_synapse_targets',
 'coregistration_auto_phase3_fwd_apl_vess_combined',
 'coregistration_manual_v4',
 'vortex_manual_myelination_v0',
 'synapses_pni_2',
 'nucleus_detection_v0',
 'vortex_manual_nodes_of_ranvier',
 'vortex_astrocyte_proofreading_status',
 'bodor_pt_target_proofread',
 'nucleus_functional_area_assignment',
 'coregistration_auto_phase3_fwd',
 'synapse_target_structure',
 'proofreading_status_and_strategy',
 'aibs_metamodel_celltypes_v661']

For each table, you can see the metadata describing that table. For example, let’s look at the nucleus_detection_v0 table:

client.materialize.get_table_metadata('nucleus_detection_v0')
{'aligned_volume': 'minnie65_phase3',
 'created': '2020-11-02T18:56:35.530100',
 'id': 45664,
 'schema': 'nucleus_detection',
 'table_name': 'nucleus_detection_v0',
 'valid': True,
 'schema_type': 'nucleus_detection',
 'user_id': '121',
 'description': 'A table of nuclei detections from a nucleus detection model developed by Shang Mu, Leila Elabbady, Gayathri Mahalingam and Forrest Collman. Pt is the centroid of the nucleus detection. id corresponds to the flat_segmentation_source segmentID. Only included nucleus detections of volume>25 um^3, below which detections are false positives, though some false positives above that threshold remain. ',
 'notice_text': None,
 'reference_table': None,
 'flat_segmentation_source': 'precomputed://https://bossdb-open-data.s3.amazonaws.com/iarpa_microns/minnie/minnie65/nuclei',
 'write_permission': 'PRIVATE',
 'read_permission': 'PUBLIC',
 'last_modified': '2022-10-25T19:24:28.559914',
 'segmentation_source': '',
 'pcg_table_name': 'minnie3_v1',
 'last_updated': '2024-10-24T22:00:00.145632',
 'voxel_resolution': [4.0, 4.0, 40.0]}

You get a dictionary of values. Two fields are particularly important: the description, which offers a text description of the contents of the table and voxel_resolution which defines how the coordinates in the table are defined, in nm/voxel.

Annotation tables

You can also find a semantic description of the most commonly used tables at the Annotation Tables page.

Querying Tables

To get the contents of a table, use the query_table function. This will return the whole contents of a table without any filtering, up to for a maximum limit of 200,000 rows. The table is returned as a Pandas DataFrame and you can immediately use standard Pandas function on it.

cell_type_df = client.materialize.query_table('nucleus_detection_v0')
cell_type_df.head()
id created superceded_id valid volume pt_supervoxel_id pt_root_id pt_position bb_start_position bb_end_position
0 730537 2020-09-28 22:40:41.780734+00:00 NaN t 32.307937 0 0 [381312, 273984, 19993] [nan, nan, nan] [nan, nan, nan]
1 373879 2020-09-28 22:40:41.781788+00:00 NaN t 229.045043 96218056992431305 864691136090135607 [228816, 239776, 19593] [nan, nan, nan] [nan, nan, nan]
2 601340 2020-09-28 22:40:41.782714+00:00 NaN t 426.138010 0 0 [340000, 279152, 20946] [nan, nan, nan] [nan, nan, nan]
3 201858 2020-09-28 22:40:41.783784+00:00 NaN t 93.753836 84955554103121097 864691135373893678 [146848, 213600, 26267] [nan, nan, nan] [nan, nan, nan]
4 600774 2020-09-28 22:40:41.785273+00:00 NaN t 135.189791 0 0 [339120, 276112, 19442] [nan, nan, nan] [nan, nan, nan]
Caution

While most tables are small enough to be returned in full, the synapse table has hundreds of millions of rows and is too large to download this way

Tables have a collection of columns, some of which specify point in space (columns ending in _position), some a root id (ending in _root_id), and others that contain other information about the object at that point. Before describing some of the most important tables in the database, it’s useful to know about a few advanced options that apply when querying any table.

  • desired_resolution : This parameter allows you to convert the columns specifying spatial points to different resolutions. Many tables are stored at a resolution of 4x4x40 nm/voxel, for example, but you can convert to nanometers by setting desired_resolution=[1,1,1].
  • split_positions : This parameter allows you to split the columns specifying spatial points into separate columns for each dimension. The new column names will be the original column name with _x, _y, and _z appended.
  • select_columns : This parameter allows you to get only a subset of columns from the table. Once you know exactly what you want, this can save you some cleanup.
  • limit : This parameter allows you to limit the number of rows returned. If you are just testing out a query or trying to inspect the kind of data within a table, you can set this to a small number to make sure it works before downloading the whole table. Note that this will show a warning so that you don’t accidentally limit your query when you don’t mean to.

For example, using all of these together:

cell_type_df = client.materialize.query_table('nucleus_detection_v0', split_positions=True, desired_resolution=[1,1,1], select_columns=['pt_position', 'pt_root_id'], limit=10)
cell_type_df
pt_position_x pt_position_y pt_position_z pt_root_id
0 241856.0 374464.0 838720.0 0
1 227200.0 389120.0 797160.0 0
2 230144.0 422336.0 795320.0 0
3 239488.0 386432.0 794120.0 0
4 239744.0 423488.0 803120.0 864691136050815731
5 245888.0 384512.0 800120.0 0
6 249792.0 391680.0 807080.0 0
7 243328.0 403008.0 794280.0 0
8 247872.0 386816.0 805320.0 0
9 260352.0 416640.0 802360.0 864691135013273238

Filtering Queries

Filtering tables so that you only get data about certain rows back is a very common operation. While there are filtering options in the query_table function (see documentation for more details), a more unified filter interface is available through a “table manager” interface.

Rather than passing a table name to the query_table function, client.materialize.tables has a subproperty for each table in the database that can be used to filter that table.

The general pattern for usage is

client.materialize.tables.{table_name}({filter options}).query({format and timestamp options})

where {table_name} is the name of the table you want to filter, {filter options} is a collection of arguments for filtering the query, and {format and timestamp options} are those parameters controlling the format and timestamp of the query.

For example, let’s look at the table aibs_metamodel_celltypes_v661, which has cell type predictions across the dataset. We can get the whole table as a DataFrame:

cell_type_df = client.materialize.tables.aibs_metamodel_celltypes_v661().query()
cell_type_df.head()
id created valid volume pt_supervoxel_id pt_root_id id_ref created_ref valid_ref target_id classification_system cell_type pt_position bb_start_position bb_end_position
0 336365 2020-09-28 22:42:48.966292+00:00 t 272.488202 93606511657924288 864691136274724621 36916 2023-12-19 22:47:18.659864+00:00 t 336365 excitatory_neuron 5P-IT [209760, 180832, 27076] [nan, nan, nan] [nan, nan, nan]
1 110648 2020-09-28 22:45:09.650639+00:00 t 328.533443 79385153184885329 864691135489403194 1070 2023-12-19 22:38:00.472115+00:00 t 110648 excitatory_neuron 23P [106448, 129632, 25410] [nan, nan, nan] [nan, nan, nan]
2 112071 2020-09-28 22:43:34.088785+00:00 t 272.929423 79035988248401958 864691136147292311 1099 2023-12-19 22:38:00.898837+00:00 t 112071 excitatory_neuron 23P [103696, 149472, 15583] [nan, nan, nan] [nan, nan, nan]
3 197927 2020-09-28 22:43:10.652649+00:00 t 91.308851 84529699506051734 864691136050858227 13259 2023-12-19 22:41:14.417986+00:00 t 197927 nonneuron oligo [143600, 186192, 26471] [nan, nan, nan] [nan, nan, nan]
4 198087 2020-09-28 22:41:36.677186+00:00 t 161.744978 83756261929388963 864691135809440972 13271 2023-12-19 22:41:14.685474+00:00 t 198087 nonneuron astrocyte [137952, 190944, 27361] [nan, nan, nan] [nan, nan, nan]

and we can add similar formatting options as in the last section to the query function:

cell_type_df = client.materialize.tables.aibs_metamodel_celltypes_v661().query(split_positions=True, desired_resolution=[1,1,1], select_columns=['pt_position', 'pt_root_id', 'cell_type'], limit=10)
cell_type_df
cell_type pt_position_x pt_position_y pt_position_z pt_root_id
0 23P 257600.0 487936.0 802760.0 864691135724233643
1 23P 260992.0 493568.0 801560.0 864691136436395166
2 NGC 256256.0 466432.0 831040.0 864691135462260637
3 23P 255744.0 480640.0 833200.0 864691136723556861
4 23P 262144.0 505856.0 824880.0 864691135776658528
5 23P 257536.0 521728.0 804440.0 864691135941166708
6 23P 251840.0 552896.0 832320.0 864691135545065768
7 23P 251136.0 546048.0 821320.0 864691135479369926
8 23P 256000.0 626368.0 814000.0 864691135697633557
9 astrocyte 324096.0 417920.0 658880.0 864691135937358133

However, now we can also filter the table to get only cells that are predicted to have cell type "BC" (for “basket cell”).

my_cell_type = "BC"
client.materialize.tables.aibs_metamodel_celltypes_v661(cell_type=my_cell_type).query()
id_ref created_ref valid_ref target_id classification_system cell_type id created valid volume pt_supervoxel_id pt_root_id pt_position bb_start_position bb_end_position
0 43009 2023-12-19 22:48:53.577191+00:00 t 369908 inhibitory_neuron BC 369908 2020-09-28 22:40:41.814964+00:00 t 332.862751 96002690286851358 864691136522768017 [227104, 207840, 20841] [nan, nan, nan] [nan, nan, nan]
1 12051 2023-12-19 22:40:57.133228+00:00 t 193846 inhibitory_neuron BC 193846 2020-09-28 22:40:41.897904+00:00 t 306.148966 82838443188669165 864691135684976823 [131568, 168496, 16452] [nan, nan, nan] [nan, nan, nan]
2 83044 2023-12-19 22:58:50.269173+00:00 t 615735 inhibitory_neuron BC 615735 2020-09-28 22:40:41.957345+00:00 t 314.539540 112181247505371364 864691136311774525 [344880, 161104, 17084] [nan, nan, nan] [nan, nan, nan]
3 48718 2023-12-19 22:50:21.192138+00:00 t 401681 inhibitory_neuron BC 401681 2020-09-28 22:40:42.066718+00:00 t 497.801462 98465046644219429 864691136052141043 [245232, 203952, 21268] [nan, nan, nan] [nan, nan, nan]
4 82324 2023-12-19 22:58:39.896999+00:00 t 613047 inhibitory_neuron BC 613047 2020-09-28 22:40:41.982376+00:00 t 242.159780 113234168401651200 864691136065413528 [352688, 141616, 25312] [nan, nan, nan] [nan, nan, nan]
... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ...
3360 8968 2023-12-19 22:40:09.246333+00:00 t 170777 inhibitory_neuron BC 170777 2020-09-28 22:45:25.310708+00:00 t 499.103662 81230957054577082 864691135065994564 [119600, 250560, 15373] [nan, nan, nan] [nan, nan, nan]
3361 15548 2023-12-19 22:41:48.382554+00:00 t 208056 inhibitory_neuron BC 208056 2020-09-28 22:45:25.401800+00:00 t 521.621668 84540007091735344 864691135801456226 [143472, 262944, 23693] [nan, nan, nan] [nan, nan, nan]
3362 79472 2023-12-19 22:57:53.993099+00:00 t 591219 inhibitory_neuron BC 591219 2020-09-28 22:45:25.526753+00:00 t 567.517839 110216764830845707 864691135279126177 [330320, 204752, 25060] [nan, nan, nan] [nan, nan, nan]
3363 55791 2023-12-19 22:52:02.582669+00:00 t 438586 inhibitory_neuron BC 438586 2020-09-28 22:45:25.430745+00:00 t 529.501389 99807894274485381 864691135395662581 [254912, 247440, 23680] [nan, nan, nan] [nan, nan, nan]
3364 50504 2023-12-19 22:50:48.576826+00:00 t 419363 inhibitory_neuron BC 419363 2020-09-28 22:45:25.436862+00:00 t 530.642698 99716496901116512 864691136691390838 [254416, 90336, 20469] [nan, nan, nan] [nan, nan, nan]

3365 rows × 15 columns

or maybe we just want the cell types for a particular collection of root ids:

my_root_ids = [864691135771677771, 864691135560505569, 864691136723556861]
client.materialize.tables.aibs_metamodel_celltypes_v661(pt_root_id=my_root_ids).query()
id created valid volume pt_supervoxel_id pt_root_id id_ref created_ref valid_ref target_id classification_system cell_type pt_position bb_start_position bb_end_position
0 19116 2020-09-28 22:41:51.767906+00:00 t 301.426115 74737997899501359 864691135771677771 11282 2023-12-19 22:40:43.249642+00:00 t 19116 excitatory_neuron 23P [72576, 108656, 20291] [nan, nan, nan] [nan, nan, nan]
1 21783 2020-09-28 22:41:59.966574+00:00 t 263.637074 75795590176519004 864691135560505569 15681 2023-12-19 22:41:50.365399+00:00 t 21783 excitatory_neuron 23P [80128, 124000, 16563] [nan, nan, nan] [nan, nan, nan]
2 4074 2020-09-28 22:42:41.341179+00:00 t 313.678234 73543309863605007 864691136723556861 50080 2023-12-19 22:50:42.474168+00:00 t 4074 excitatory_neuron 23P [63936, 120160, 20830] [nan, nan, nan] [nan, nan, nan]

You can get a list of all parameters than be used for querying with the standard IPython/Jupyter docstring functionality, e.g. client.materialize.tables.aibs_metamodel_celltypes_v661.

Caution

Use of this functionality will show a brief warning that the interface is experimental. This is because the interface is still being developed and may change in the near future in response to user feedback.

Querying Proofread neurons

Proofread neurons

Proofreading is necessary to obtain accurate reconstructions of a cell. In the MICrONS dataset, the general rule is that dendrites onto cells with a single cell body are sufficiently proofread to trust synaptic connections onto a cell. Axons on the other hand require so much proofread that only ~1,000 cells have axons that were proofread to various degrees such that their outputs can be used for analysis.

The table proofreading_status_and_strategy contains proofreading information about ~1,300 neurons. This website provides the most detailed overview. In brief, axons annotated with any strategy_axon were cleaned of false mergers but not all were fully extended. The most important distinction is axons annotated with axon_column_truncated were only proofread within a certain volume wheras others were proofread without such bias.

proof_all_df = client.materialize.query_table("proofreading_status_and_strategy", desired_resolution=[1, 1, 1], split_positions=True)
proof_all_df["strategy_axon"].value_counts()
strategy_axon
axon_partially_extended    979
axon_column_truncated      233
none                       185
axon_interareal            144
axon_fully_extended         80
Name: count, dtype: int64

We can filter our query to only return rows that match a condition by adding a filter to our query:

proof_df = client.materialize.query_table("proofreading_status_and_strategy", filter_in_dict={"strategy_axon": ["axon_partially_extended", "axon_fully_extended", "axon_interareal", "axon_column_truncated"]}, desired_resolution=[1, 1, 1], split_positions=True)
proof_df["strategy_axon"].value_counts()
strategy_axon
axon_column_truncated      598
axon_partially_extended    341
axon_interareal            146
axon_fully_extended         77
Name: count, dtype: int64
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