: 158–9  Brazelton argues that too much cheering a child up devalues the emotion of sadness for them;: 52  and Selma Fraiberg suggests that it is important to respect a childs right to experience a loss fully and deeply.Margaret Mahler also saw the ability to feel sadness as an emotional achievement, as opposed for example to warding it off through restless hyperactivity. D. W. Winnicott similarly saw in sad crying the psychological root of valuable musical experiences in later life. Neuroanatomy
A large amount of research has been conducted on the neuroscience of sadness. According to the American Journal of Psychiatry, sadness has been found to be associated with "increases in bilateral activity within the vicinity of the middle and posterior temporal cortex, lateral cerebellum, cerebellar vermis, midbrain, putamen, and caudate." Jose V. Pardo has his M.D and Ph.D and leads a research program in cognitive neuroscience. Using positron emission tomography (PET) Pardo and his colleagues were able to provoke sadness among seven normal men and women by asking them to think about sad things. They observed increased brain activity in the bilateral inferior and orbitofrontal cortex. In a study that induced sadness in subjects by showing emotional film clips, the feeling was correlated with significant increases in regional brain activity, especially in the prefrontal cortex, in the region called Brodmanns area 9, and the thalamus. A significant increase in activity was also observed in the bilateral anterior temporal structures.
Neonatal alloimmune thrombocytopenia (NAITP, NAIT, NATP or NAT) is a disease that affects babies in which the platelet count is decreased because the mothers immune system attacks her fetus or newborns platelets. A low platelet count increases the risk of bleeding in the fetus and newborn. If the bleeding occurs in the brain, there may be long-term effects. Platelet antigens are inherited from both mother and father. NAIT is caused by antibodies specific for platelet antigens inherited from the father but which are absent in the mother. Fetomaternal transfusions (or fetomaternal hemorrhage) results in the recognition of these antigens by the mothers immune system as non-self, with the subsequent generation of allo-reactive antibodies which cross the placenta. NAIT, hence, is caused by transplacental passage of maternal platelet-specific alloantibody and rarely human leukocyte antigen (HLA) allo-antibodies (which are expressed by platelets) to fetuses whose platelets express the corresponding antigens. NAIT occurs in somewhere between 1/800 and 1/5000 live births. More recent studies of NAIT seem to indicate that it occurs in around 1/600 live births in the Caucasian population. Signs and symptoms
The diagnosis of NAIT is usually made after an incidental finding of a low platelet count on a blood test or because of bleeding complications ranging from bruising or petechiae to intracranial hemorrhage in the fetus or newborn.Frequently, the reduction in platelet count is mild and the affected neonates remain largely asymptomatic.