Systems, devices, and methods related to a deep learning accelerator and memory are described. For example, a wearable electronic device may be configured to execute instructions with matrix operands and configured with: a housing to be worn on a person; a sensor having one or more sensor elements generate measurements associated with the person; random access memory to store instructions executable by the deep learning accelerator and store matrices of an artificial neural network; a transceiver; and a controller to monitor an output of the artificial neural network, generated using the measurements as an input to the artificial neural network. Based on the output, the controller may control selective storage of measurement data from the sensor, and/or selective communication of data from the wearable electronic device to a separate computer system.