{\displaystyle \pi _{1}(\mathbf {T} ^{2})=\pi _{1}(S^{1})\times \pi _{1}(S^{1})\cong \mathbf {Z} \times \mathbf {Z} .} Intuitively speaking, this means that a closed path that circles the torus "hole" (say, a circle that traces out a particular latitude) and then circles the torus "body" (say, a circle that traces out a particular longitude) can be deformed to a path that circles the body and then the hole. So, strictly latitudinal and strictly longitudinal paths commute. An equivalent statement may be imagined as two shoelaces passing through each other, then unwinding, then rewinding. If a torus is punctured and turned inside out then another torus results, with lines of latitude and longitude interchanged. This is equivalent to building a torus from a cylinder, by joining the circular ends together, in two ways: around the outside like joining two ends of a garden hose, or through the inside like rolling a sock (with the toe cut off). Additionally, if the cylinder was made by gluing two opposite sides of a rectangle together, choosing the other two sides instead will cause the same reversal of orientation. The first homology group of the torus is isomorphic to the fundamental group (this follows from Hurewicz theorem since the fundamental group is abelian). Two-sheeted cover
The 2-torus double-covers the 2-sphere, with four ramification points. Every conformal structure on the 2-torus can be represented as a two-sheeted cover of the 2-sphere. The points on the torus corresponding to the ramification points are the Weierstrass points.
The disorder is extraordinarily rare with fewer than 100 recorded cases. While individuals of all backgrounds have been reported with the disorder, there is a higher inclination towards males (75% or more). The average age of those with Ganser syndrome is 32, though it stretches from ages 15–62 years old. Differential diagnosis
Factitious disorder should be distinguished from somatic symptom disorder (formerly called somatization disorder), in which the patient is truly experiencing the symptoms and has no intention to deceive. In conversion disorder (previously called hysteria), a neurological deficit appears with no organic cause. The patient, again, is truly experiencing the symptoms and signs and has no intention to deceive. The differential also includes body dysmorphic disorder and pain disorder. Treatment
No true psychiatric medications are prescribed for factitious disorder. However, selective serotonin reuptake inhibitors (SSRIs) can help manage underlying problems. Medicines such as SSRIs that are used to treat mood disorders can be used to treat factitious disorder, as a mood disorder may be the underlying cause of factitious disorder. Some authors (such as Prior and Gordon 1997) also report good responses to antipsychotic drugs such as Pimozide. Family therapy can also help. In such therapy, families are helped to better understand patients (the individual in the family with factitious disorder) and that persons need for attention. In this therapeutic setting, the family is urged not to condone or reward the factitious disorder individuals behavior. This form of treatment can be unsuccessful if the family is uncooperative or displays signs of denial and/or antisocial disorder.