Clarify nest device trigger documentation

source/_integrations/nest.markdown

@@ -40,6 +40,7 @@ Home Assistant is integrated with the following devices through the SDM API:
   - Example devices: All Google Nest Thermostat models
 - Display, Camera, and Doorbell Devices
   - The camera live stream is available as a `camera` entity
+  - Device Triggers for use in automations such as Person detected, Motion detected and Doorbell pressed
   - Example devices: All Google Nest Cam models, Google Nest Hello Video Doorbell, Google Nest Hub Max
 
 You are in control of the information and capabilities exposed to Home Assistant. You can authorize a single device, multiple devices, or different levels of functionality such as motion events, live streams, for any particular device. The integration is flexible enough to adapt based on what you allow.
@@ -252,14 +253,26 @@ Given a thermostat named `Upstairs` then sensors are created with names such as
 
 ## Automation and Device Triggers
 
-All Google Nest Cam models and the Google Nest Hello Video Doorbell support [Device Triggers](/docs/automation/trigger/#device-triggers) that enable automation in Home Assistant:
+The Nest integration makes [device triggers](/docs/automation/trigger/#device-triggers) available to enable automation
+in Home Assistant. You should review the [Automating Home Assistant](/getting-started/automation/) getting started guide on automations or the [Automation](/docs/automation/) documentation for full details.
 
-- `camera_motion`: Motion detected, when a [CameraMotion](https://developers.google.com/nest/device-access/traits/device/camera-motion#events) event is received.
-- `camera_person`: Person detected, when a [CameraPerson](https://developers.google.com/nest/device-access/traits/device/camera-person#events) event is received.
-- `camera_sound`: Sound detected, when a [CameraSound](https://developers.google.com/nest/device-access/traits/device/camera-sound#events) event is received.
-- `doorbell_chime`: Doorbell pressed, when a [DoorbellChime](https://developers.google.com/nest/device-access/traits/device/doorbell-chime#events) event is received.
+![Screenshot Device Triggers](/images/integrations/nest/device_triggers.png)
 
-See [Automating Home Assistant](/getting-started/automation/) for the getting started guide on automations or the [Automation](/docs/automation/) documentation for full details.
+All Google Nest Cam models and the Google Nest Hello Video Doorbell support device triggers:
+
+- **Motion detected**
+- **Person detected**
+- **Sound detected**
+- **Doorbell pressed** *for Google Nest Hello Video Doorbell only*
+
+The lower level Pub/Sub subscriber receives events in real time and internally fires `nest_event` events within Home Assistant:
+
+| Device Trigger | Pub/Sub Event | `nest_event` |
+| -------------- | ----- | ------------- |
+| Motion detected | [CameraMotion](https://developers.google.com/nest/device-access/traits/device/camera-motion#events) | `motion_detected` |
+| Person detected | [CameraPerson](https://developers.google.com/nest/device-access/traits/device/camera-person#events) | `person_detected` |
+| Sound detected | [CameraSound](https://developers.google.com/nest/device-access/traits/device/camera-sound#events) | `sound_detected` |
+| Doorbell pressed | [DoorbellChime](https://developers.google.com/nest/device-access/traits/device/doorbell-chime#events) | `doorbell_chime` |
 
 
 # Legacy Works With Nest API