Memorial Service for "Hannah" and "Heidi"
Tuesday, April 23, 2002
Noon to 1:30 pm
University of Toronto Faculty of Dentistry
124 Edward Street
(1 block north of Dundas, between University and Bay)
Activists from Freedom for Animals, Ark II, Action Volunteers for Animals, and University of Toronto Animal Rights Advocates will gather at the U of T Faculty of Dentistry to mourn the senseless deaths of "Hannah" and "Heidi", two macaque monkeys who were subjected to invasive brain experiments and then killed.
Please bring flowers and other tokens to create a memorial at the site.
Hannah and Heidi were two young female monkeys, known only as H5 and H6 to researcher Barry Sessle and his graduate students Gregory Murray, Li-Deh Lin, and Ekram Mahmoud Moustafa. (Activists named them "Hannah" and "Heidi" posthumously.)
The researchers implanted two metal cylinders in each monkey's skull through which electrodes could be inserted to electrically stimulate different parts of the brain. Hannah and Heidi also had "headcap[s] of dental acrylic fixed to the skull" each of which had a brass bolt 1 cm across which was used to hold the head still during experimentation. Additional electrodes were inserted in different muscles used for chewing and swallowing.
While fully conscious, Hannah and Heidi were restrained in "primate chairs" with their heads immobilized by "headholders".
As thirst was used as a training motivator, Hannah and Heidi were given only two thirds of their normal water intake (except on weekends when they could drink their fill). They had to learn to bite or stick out their tongues in response to a computer signal in order to get a small amount of juice as a reward.
After training, the experimenters then cooled parts of the brain to 2-4 C.
Hannah and Heidi would then lose control of the muscles controlled by those parts of the brain (i.e. those used to chew, swallow, stick out their tongues).
The experimenters also poked Hannah and Heidi's faces and mouths with cotton swabs, their fingers, or probes and measured any resulting brain activity.
On other occasions, the experimenters would electrically stimulate parts of Hannah and Heidi's brains, causing them to move against their will. (Remember, the monkeys were fully conscious for all of these experiments--they were not even given sedatives.)
Experiments published in 1991, 1992, 1994, and 1998 mention Hannah and Heidi specifically. Hannah was also used in an experiment published in 1997, along with another monkey.
It is not known how long in total Hannah and Heidi were imprisoned in the Faculty of Dentistry and experimented on. One article, published in 1994, mentions experiments which were spread out over an entire year.
Ultimately, Hannah and Heidi were killed by the experimenters.
The experiments in which Hannah and Heidi suffered and died are part of a series of monkey brain experiments Barry Sessle began in 1982. The Canadian
Institutes for Health Research continues to Barry Sessle's research: for the 2001-2002 academic year, Sessle received $120,417 for "Neural mechanisms of orofacial function" and $200,000 as a Canada Research Chairholder.
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