## 3 Results: Publication Analysis
### Relationships between Sense of Presence and the Study Variables
#### 3.4.1 Relationships between Sense of Presence and Environmental Stimuli
Study [23] is notable in that it registered improvements in spatial memory in response to stimuli affecting different sensory channels (auditory, tactile, smell), underlining the potential of multisensory configurations to reduce cognitive biases in virtual environments. Regarding emotional responses, [24] noted trends in specific changes in anxiety, sadness and relaxation, in relation to stimulation type (smell or tactile). The lack of significance in the results found by these authors shows that more evidence is needed to establish solid patterns in the evocation of emotions by the environmental stimuli used in virtual environments. Study [20] examined the effects on presence of including an avatar in the virtual environment. The results revealed that users felt more fear when an avatar was present than in the control condition without the avatar. However, the authors suggested \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Ref.** & **Categories** & \multicolumn{2}{c}{**Human Responses (HR)**} & \multicolumn{2}{c}{**HR Behavior**} \\ \hline \multicolumn{2}{c}{**Environmental Stimuli with Effects on HR**} & \multicolumn{2}{c}{**Presence Indicators**} & \multicolumn{2}{c}{**HR is (\textless{} / \(\equiv\) / \textgreater{}) in (A) than in (B)**} \\ \hline  & & & Anxiety & & (Smell) 1 & \(>\) & (Cortrol), (Texture), (Both) & (Control), (Texture), (Control), (Smell), (Both) & (Control), (Smell), (Control), (Smell), (Smell), (Both) & (Control), (Smell), (Control), (Smell), (Both) & (Control) \\  & & & & & & (Smell), (Texture), (Both) & (Control) \\  & & & & & & (Smell), (Texture), (Both) & (Control) \\  & & & & & & (Smell), (Texture), (Both) & (Control) \\  & & & & & & (Smell), (Texture), (Both) & (Control) \\  & & & & & & (Smell), (Texture), (Both) & (Control) \\ \hline
[20] & \begin{tabular}{c} Stimulus \\ Scenery \\ Stimulus \\ \end{tabular} & \begin{tabular}{c} Sociocultural, \\ Comparative, \\ \end{tabular} & \begin{tabular}{c} Co-presence \\ External/Internal \\ \end{tabular} & \
\begin{tabular}{c} Invol./Att. \\ Emotion (Fear) \\ \end{tabular} &
\begin{tabular}{c} (NPC) \\ (NPC) \\ \end{tabular} & \(>\) & (Control) \\ \hline
[69] & \begin{tabular}{c} Stimulus \\ Scociultural, \\ \end{tabular} & \begin{tabular}{c} Affordances \\ \end{tabular} & \
\begin{tabular}{c} Engagement \\ Naturalness, CS \\ motor responses \\ \end{tabular} &
\begin{tabular}{c} (Interactive) \\ \end{tabular} & \(>\) & (Control) \\ \hline
[70] & \begin{tabular}{c} Stimulus \\ Stimulus \\ Stimulus \\ \end{tabular} & \begin{tabular}{c} Sociocultural, \\ Sococultural, \\ Sococultural, \\ Semantic \\ \end{tabular} & \begin{tabular}{c} Affordances \\ Co-presence \\ Semantic \\ \end{tabular} & \begin{tabular}{c} Realism, \\ Invol./Att. \\ Nonol./Att. \\ Nonol./Att. \\ Nonol./Att. \\ Non./Att. \\ Non./Att. \\ Non./Att. \\ Non./Att. \\ \end{tabular} & \
\begin{tabular}{c} (Navigation) \\ \(\equiv\) \\ (Navigation) \\ (Animation) \\ \end{tabular} & \(\equiv\) &
\begin{tabular}{c} (Control) \\ (Control) \\ (No \\ interaction) \\ \end{tabular} \\ \hline \hline \end{tabular} Note. 1 This result is indicated as a trend by the authors. M: Moderator effect; S: Sensation; CS: Cybersickness; En: Engagement; Nat: Naturalness; Invol./Att.: Involvement/Attention; AV: Affective Valence.  
\end{table} 
Table 11: _Cont._that this was due to the role of the avatar, a police officer chasing the user. Nonetheless, this finding highlights the emotional impact that a feeling of copresence with other virtual actors can exert. Study [69] evaluated interactive versus non-interactive affordances, noting that, although affordances may increase sense of presence, their effect critically depends on the level of interactivity of the VE, which in turn can improve engagement. Along the same lines, [51] found that the mere fact of believing they can interact within a VE has no effect on participants' sense of presence: the effect is only enhanced when the participants carry out interactions successfully.