The deficit in stimulus-reward functions was demonstrated by Oscar-Berman and Pulaski who presented patients with reinforcements for certain stimuli but not others, and then required the patients to distinguish the rewarded stimuli from the non-rewarded stimuli. WKS patients displayed significant deficits in this task. The researchers were also successful in displaying a deficit in recognition memory by having patients make a yes/no decision as to whether a stimulus was familiar (previously seen) or novel (not previously seen). The patients in this study also showed a significant deficit in their ability to perform this task. Confabulation
People with WKS often show confabulation, spontaneous confabulation being seen more frequently than provoked confabulation. Spontaneous confabulations refer to incorrect memories that the patient holds to be true, and may act on, arising spontaneously without any provocation. Provoked confabulations can occur when a patient is cued to give a response, this may occur in test settings. The spontaneous confabulations viewed in WKS are thought to be produced by an impairment in source memory, where they are unable to remember the spatial and contextual information for an event, and thus may use irrelevant or old memory traces to fill in for the information that they cannot access. It has also been suggested that this behaviour may be due to executive dysfunction where they are unable to inhibit incorrect memories or because they are unable to shift their attention away from an incorrect response. Causes
WKS is usually found in people who have used alcohol chronically. Wernicke–Korsakoff syndrome results from thiamine deficiency.
Progesterone vaginal ring, also known as progesterone-only vaginal ring, is a form of vaginal ring used for birth control when breastfeeding. Use can begin at four weeks and continue for at least up to a year following childbirth. Failure rates with usual use is about 1.5 per 100 women. It is used within the vagina with one ring lasting three months. The woman is able to place and remove the ring herself. It is sold under the brand names Progering among others.Side effects include vaginal discharge and pain with urination. It does not appear to be associated with serious side effects. With use menstrual periods often do not resume. It was specifically made for use with breastfeeding as it does not affect milk production. It works by gradually releasing the hormone progesterone.Progesterone vaginal rings have been approved for medical use since 1998. It is on the World Health Organizations List of Essential Medicines. As of 2014, they are available in a number of South and Central American countries. As of 2016, it is not available in the United States. It was developed by the Population Council. See also
Pharmacokinetics of progesterone § Vaginal administration


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