# Artificial Subjectivity: Personal Semantic Memory Model for Cognitive Agents
## 2 Related Work
### Proposed Architecture  
**Sensory memory** is the short-term memory of the agent received the external information \(l_{external}\) from sensors. \(l_{external}\) come as an input to the system in textual form. It consisted of a single sentence or multiple sentences. A sensory memory function named \(f_{sensory\ memory}\) in sensory memory was running that received the external information and tokenize it into sentences and words represented as low-level percepts. These low-level percepts named \(Percepts_{s}\) in Equation (1). The function \(f_{sensory\ memory}\) invoked the perception unit carrying the low-level percepts to the perception unit for further processing. \[percepts_{s}=f_{sensory\ memory}(I_{external})\,, \tag{1}\]  
**The perception** unit received the low-level percepts and performed the perception into three fragments: lingual perception, personality perception, and emotion perception. It holds perception information of agent, object, and recipient. In these fragments, perception of emotion, personality, and language took place. A perception function named \(f_{perception}\) was responsible for lingual perception, personality perception, and emotion perception. The output of this function was represented as high-level percepts, denoted as \(percepts_{p}\) in Equation (2). High-level percept consisted of the knowledge about the agent, action, recipient, personality, emotion, and sentiments and represented using language data frame in the form of name-value pairs. Action from the lingual perception was acted as a cue in working memory for fetching the relevant knowledge from the semantic memory. \[percepts_{p}=f_{perception}(percepts_{s}) \tag{2}\]  
**Working memory** was the executive control unit where the current knowledge temporarily resides named as content space \(C\). A working memory function named (\(f_{fc}\)) fetched the relevant knowledge from the semantic memory and the episodic memory based on the cue from \(percepts_{p}\). It retrieved the number of chunks \(C_{1},\ C_{2},\ C_{3},\ C_{4},\ C_{5}\dots\dots\ C_{n}\) from semantic memory denoted as \(C_{SM}\) in Equation (4). Chunks \(C_{1},\ C_{2},\ C_{3},\ C_{4},\ C_{5}\dots\dots\ C_{n}\) from episodic memory is denoted as \(C_{EM}\) in Equation (5). The chunk of content space \(C\) consisted of the percepts, \(C_{SM}\) and \(C_{EM}\) at this stage as shown in Equation (6) and Figure 2. This content space was used by the second phase for personal semantic formulation. \[C_{i}=f_{fc}(cue),\ \ i=SM,\ EM \tag{3}\]  
\[C_{SM}\text{: }C_{1},\ C_{2},\ C_{3},\ C_{4},\ C_{5}\dots\dots\ C_{n}, \tag{4}\]  
\[C_{EM}\text{: }C_{1},\ C_{2},\ C_{3},\ C_{4},\ C_{5}\dots\dots\ C_{n}, \tag{5}\]  
\[C\text{: }C_{SM}C_{EM},\ percepts \tag{6}\]  
Figure 2: Content Space in working memory. **Semantic Memory** is long-term memory that holds the general knowledge that plays a key role in the perceptual semantic phase [10; 31]. Here the semantic knowledge helped in analyzing the positivity and negativity of action performed for example if the agent receives external information \"_[PERSON] helps [PERSON]_\", how the agent can evaluate that some positive action has been performed by the [PERSON]? Semantic knowledge against the action \"_help_\" was required to evaluate the person [PERSON] for his action to build a type of person semantics like \"_[PERSON] is a good person_\", \"_I like [PERSON]_\", and \"_I always find [PERSON] doing good_\". Semantic memory can be constructed using conceptual graphs, semantic networks, etc. In this work, a semantic memory was constructed using knowledge graphs considering the benefits of knowledge graphs for easy extraction of complex knowledge [32]. **Episodic Memory** is the long-term memory accumulated the event knowledge in the form of episodes. Episodic memory stored the seven aspects of each event in the form of an episode.