| Definition of "zones of interest" (that is a specific area into the scenery with some behavioural meaning for the user) is an easy task by using the drawing tools offered by SMART. Figure 1Figure 1. Aspect of the "zones editor" screen [click here to see image].
The drawing tools must be selected according to the shape to be defined (circular, square, irregular polygons, circle segment or free-hand drawn zones are available) and according to the zone to which the covered surface is to be assigned.
The scenery in which zones are to be defined is present in the computer screen and used to draw the zones behind.
The scenery image can be refreshed as many times as necessary just by pressing the "get image" button in the screen. In figure 1, the appearance of the "zones editor" screen is shown. In the video screen (left of the screen), on a "T" maze is superimposed the drawn of several zones. The cursor is over the "zone 5" ("zone 5" is the default name of the zone identified with the sky-blue colour), as indicated by the coloured bar below the button allowing for the edition of the names of the zones. Cursor position (in x, y co-ordinates, in absolute or in user values if defined) is always shown at the bottom right corner. |
| Figure 2Figure 2. Seeing zones as surfaces.A button allows for the seeing of the full zones surface [click here to see image].
A zone is defined by selecting a drawing tool and a drawing colour (selecting it from the zones selecting pad in the middle right of the screen).
Once a draw is done in the video screen, the pixels under the virtual surface of the draw are assigned to the corresponding zone; a zone must be always a closed surface.
To make easy the draw, only the perimeter of the zone is shown, thus making possible to continue seeing the working scenery. |
Figure 3Figure 3. Additionally, a magnifier tool, an eraser, a filling and a selecting tool are also provided (see second line).
Besides the possibility of draw by picking and dragging with the mouse, it is also possible to draw by stating the origin co-ordinates, the width and height values of the figure and then press a "draw now" button (see figure 3, bottom line). In this way several zones with the same dimensions can be drawn repetitively. |
| Figure 4Figure 4 show some samples of the versatility of the drawing tools offered by SMART. Some "zones", as done with the SMART's drawing tools [click here to see image].
Once a "zone definition" is completed, it can be filed and recovered latterly as many times as necessary. It is important to note that a zone definition is linked to a real scenery and is valid only when the recording conditions (camera position and focus) correspond exactly to those prevalent at the moment of the definition.
Other important point is the full independence between motor activity data and zones definition (this is entirely true for position tracking but arguable for motor activity analysis; it will be discussed later). This means that all track information can be analysed using as many different zone definitions as necessary (even that each one of them needs to be coherent with the experimental situation, as it is obvious). In this way, data can be fully exploded in all its potentiality .
All zones have the same functional significance, except for the zone 32, that is always understood as a "zone of exclusion". The zone of exclusion is a user defined area in which no analysis must been done; it is as if the activity occurring in it where non-existent.
The zone of exclusion is a very useful tool, as allow for the virtual elimination of artefacts coming from areas without significance for the experiment (see the black area –exclusion zone– in figure 2, in which the only "active" areas are those above the maze). Other exception is the capability of design a zone as "target zone". The target zone allows for the selection of a specific working mode in which the system is running on and automatically stops when the subject reach the target.
Data analysis is carried out for each zone independently. Either activity or track analysis information is obtained referred to each zone. Additionally, the user can freely define associations between different zones, allowing for the obtainment of consolidated data referred to several combined zones. This can be important if, for instances, the experimenter want to know, at the same time, data obtained in different peripheral areas. |
