dont use array() .eg array($currentSessionData['Category'])
Try this.
$cat_ids=array(0=>10,1=>51,2=>51,3=>6561,4=>1,5=>561);
$this->YourModelName->find('all', array(
'conditions' => array(
"YourModelName.id" => cat_ids /*dont use array() */
)
));
i hope its helpful for you :)