Javascript Associative Arrays

I've spent some time  looking into Javascript associative arrays.  But javascript doesn't have associative arrays. it has objects that can have values that can be accessed in a similar way to associative arrays in perl and PHP. Im no expert but heres how I created a multidimensional javascript array  from a PHP array .
The PHP  array has 4 levels  , that are read from a database .

So I've  read data from the database and  created a multidimensional PHP associative array

$ic[$sy][$si][$pr][$co]=$value;

so the php writes some javascript