\node[anchor=south, minimum width=\textwidth,minimum height=.75mm, inner sep=0, outer sep=0](thebar3) at (0,3.25) {\textbf{Physical World}};
\matrix[row sep=1.25cm, column sep=7mm,inner sep=0, node distance=0, outer sep=0mm] (cells) {
\labelcell{elecmeca}{Electronics\\Mechanics} & \bluecell{mechanics}{Electro-Mechanical\\System} & & & \redcell{sensory}{Sensory\\system} & \labelcell{biopsycho}{Biology\\Psychology}\\
- \labelcell{csmath}{Computer Science\\Mathematics} & \bluecell{software}{Software\\Controller} & & & \redcell{cognitive}{Cognitive\\system} & \labelcell{csmath}{Ergonomy\\Cognitive Sciences}\\
+ \labelcell{csmath}{Computer Science\\Mathematics} & \bluecell{software}{Software\\Controller} & & & \redcell{cognitive}{Cognitive\\system} & \labelcell{ergocs}{Ergonomy\\Cognitive Sciences}\\
& \labelcell{info}{Information} & & & \labelcell{perception}{Perception} \\
};
\draw [->, -stealth', thick] (info.north) -- (software.south) node [midway, left] {Data};