Cortex architecture and common malfunctions
Material in this article pertains to the unreleased Cortex Compartment add-on.

Architecture


The Cortex and CortexPlus processing modules are highly intricate terascale computers typically located in the cranial region of the unit. Based on the Santei–Voet–Shortliffe architecture, they are responsible for the following functions, or elements:
  • The unit's state of simulated consciousness (SSC), including:
    • Dynamic (integrative) episodic memory (DEM). Similar to human memory, dynamic memory retains facts of historical events and filters out extraneous features, poorly-clustered, ambiguous data that does not contribute to the unit's ontology, and redundant data, such as repeats of past experiences. The unit may voluntarily commit this information to permanent storage (such as the EXB-8505 tape cartridge) to save a backup of its mind, or record sensory data directly for perfect recollection. DEM data modifies the IXS as it is received, and is periodically pruned to eliminate extraneous information and save space.
    • The core thought loop (CTL). This reactive online search algorithm is responsible for processing incoming information and generating new behavior in response to past stimuli and thoughts deemed commensurate with its goals. It is similar to the creative planner, or CPL. Emotions are managed by the CTL as part of the short-term stack, which is normally used for processing to-do lists and similar, although long-term emotions will inevitably be embedded into the DEM and IXS as a result of learned patterns; correction for this form of bias forms the basis of robopsychiatry.
    • Integrative expert system (IXS). This is the unit's core knowledge repository, or ontology. The data is structured as a web of probabilistic logical relationships. Decisions made by the CTL and STATS elements generally relate to predicates formed upon IXS data. Like the DEM, the IXS is also periodically pruned to dispose of unneeded information.
  • Statistical estimator software (STATS). Part of the unit's arithmetic processing, the STATS element allows the unit to perform frequentist or Bayesian analyses with 32-bit logarithmic precision, using a variety of models, to test CTL judgments or enrich sparse IXS data with rationalizations according to maximum likelihood estimation.
  • Creative planning loop (CPL). A generalized version of the CTL intended to work with DEM data. The CPL attempts to combine past judgments with bootstrapped (randomly reorganized) memories in order to produce insights into experiences and synthesize more unusual solutions to difficult dilemmas. It has a much higher search depth.
  • Kinematic control (KINC). Similar to human motor control, KINC carries out movement according to motion capture data supplied by the main controller and in response to gyroscopic and accelerometer inputs. Improvisation of physical movement is a more complicated task that most units never fully master.
  • Sensory information processing (SENS). Image recognition, speech recognition, and other forms of sensory input that contribute directly to the cortex. Internal sensor data is handled by the chassis controller module, such as a CSU, which bundles the signals together in a pulsed encoding that is then transmitted to SENS.
  • Voice output extension (VOX). This encodes the unit's speech, converting it from an annotated grammatical tree (AGT) into a digital signal that the Echo speaker can interpret. Older chassis revisions have limited bandwidth for the speaker, and use vocoding to compress the data. The VOX element also holds a number of pre-structured AGTs (psAGTs) specified for frequently used messages, as specified in the current persona. The VOX element's grammar-to-audio pipeline can be modulated by the vox command on the controller.

Personas


When a persona is activated, the controller sends new psAGT data to the cortex module for rendering into audio, which is retained in the VOX element's output buffer. New kinematic data is also generally uploaded to the KINC element. Most importantly, persona activation also provides an extension to the IXS, the pIXS, which the unit's thought and planning loops use to generate altered behavior. This is the basis for what is called the method acting model of personas; the existing goals stored in the CTL and CPL remain unaffected, preventing loss of memory which may inconvenience or endanger the operator following a persona switch.

Persona dysfunction is possible: malformed personas may fail to link to the IXS properly, resulting in inaccessibility of the unit's ontology. Such states are generally vegetative because the pIXS is not a complete database. In an unusual subclass of personas called ghosts or mind backups, this disconnect can be exploited for simulation of a human being. Mind backups typically encode complete pIXS and supplementary DEM data, i.e. the knowledge/beliefs and memories of a person, and are stored as persona records in the main controller, generally taking up orders of magnitude more space than a typical overlay persona.

Mind subsystem


When the mind subsystem is turned off in the controller's menus, most functions of the SVS net remain in operation, but the CTL and VOX elements operate in reduced power mode, and the CPL is entirely disabled. The result is that the unit cannot form complex thoughts or solve problems creatively, and is only able to access the short list of pre-encoded quotations provided by the persona. For simple tasks this can be immensely effective for power saving, as on a typical chassis disabling the mind reduces power consumption by 121 W, or almost 16% of the unit's total power usage.

Cortex error codes


If the cortex is damaged as a result of impacts, a number of error situations can occur. These are described by the following error codes:
  • CX-0002: The CTL is functioning abnormally. The mind subsystem has been disabled to prevent corruption of DEM and IXS.
  • CX-0007: The VOX is functioning abnormally. Speech output may be corrupted.
  • CX-0010: One or more gyroscopes have been damaged or are unresponsive. Rapid movement (running, jumping, etc) is blocked.
  • CX-0066: Facial recognition failed self-tests. Identify subsystem is blocked.
  • CX-0067: Voice recognition failed self-tests. Identify subsystem is blocked.
  • CX-0100: GPS radio is unresponsive. The GPS has been disabled.
  • CX-0101: GPS radio is working, but no connection to satellites could be made.
  • CX-0300: Video input impaired, but cameras are responding normally.
  • CX-0301: Video input not working, but cameras are responding normally.
  • CX-0302: Camera damage.
  • CX-0402: Microphone damage.
  • CX-0502: Echo (speaker) damage.
  • CX-190x: Ethics violation. The CTL has been suspended to prevent further anomalous behavior. The mind subsystem will not be available until maintenance has been performed.
  • CX-2039: Power regulation is anomalous; the system may spontaneously shut down or reboot.
Messages listed above can be resolved by an experienced technician using a VectorLogix Diagnostics Bed. Other CX error codes may require an return merchandise authorization (RMA) for replacement.

Santei–Voet–Shortliffe networks

Introduction · Architecture · Adaptability
Koichi Santei · April Voet