Gambhira is a ritual form of masked dance, performed in the Malda region of West Bengal and, formerly at least, in nearby villages of what is now Bangladesh. The name is thought to derive from an old term for the inner sanctum of a Saivite temple. The dances are traditionally part of a series of ceremonies honoring Siva and Shakti that are performed in the four days leading up to Chaitra Parva. The oldest items in the repertoire, perhaps dating back to the 7th century AD, are solo dances representing and invoking various aspects of Shakti: Kali, Narasinghi, Chamunda, Druga Mahishamardini, Giridhinivishal, Jhantakali, and Ugrachanda. These dances are extremely energetic and are marked by rapid shifts of weight, sudden drops to the knees, and the flailing of arms and pointing of fingers. The masks used for these Shakti dances are traditionally made of dumiri or margosa wood by a professional caste of Sutradhars and painted by Patuas. These masks are thought to provide a conduit for visitation. The possession of the male dancer by an aspect of Shakti is facilitated by the driving rhythms of the dholak drum and cymbals accompanying the dance, and the possession of the performer is said to provide a model for the erasure of the duality between the worshipper and the worshipped, the individual and the cosmos. Recently, possession has be deemphasized (though it still can occur). Since the early twentieth century, papier mache masks have also been made and deployed in scenes from Puranic legends that have been added to the repertoire, and even non-masked items such as the tupa "dance" depicting traditional fishing methods may be interposed, adding a more theatre-like aspect the the ritually based ceremonies.