Relationship between parenthood and cortical thickness in late adulthood

Pregnancy and the early postpartum period alter the structure of the brain; particularly in regions related to parental care. However, the enduring effects of this period on human brain structure and cognition in late life is unknown. Here we use magnetic resonance imaging to examine differences in cortical thickness related to parenthood in late life, for both sexes. In 235 healthy older women, we find a positive relationship between parity (number of children parented) and memory performance in mothers. Parity was also associated with differences in cortical thickness in women in the parahippocampus, precuneus, cuneus and pericalcarine sulcus. We also compared non-parents to parents of one child, in a sub-sample of older women (N = 45) and men (N = 35). For females, six regions differed in cortical thickness between parents and non-parents; these regions were consistent with those seen earlier in life in previous studies. For males, five regions differed in cortical thickness between parents and non-parents. We are first to reveal parenthood-related brain differences in late-life; our results are consistent with previously identified areas that are altered during pregnancy and the postpartum period. This study provides preliminary evidence to suggest that neural changes associated with early stages of parenthood persist into older age, and for women, may be related to marginally better cognitive outcomes

Cognitive changes associated with ADT: a review of the literature

The use of androgen deprivation therapy (ADT) has increased since the early 1990s after early detection efforts and greater use of the prostate-specific antigen (PSA) test. Although ADT is associated with favorable clinical outcomes, ADT has been associated with an increased risk for cardiovascular disease, increased serum cholesterol, triglycerides, insulin resistance, body mass index and fat body mass. Here we review findings from 11 clinical studies examining the effects of ADT on cognition as measured by standardized tests in cognitive domains such as verbal and spatial memory. Most of these studies have important limitations, including small sample sizes, suboptimal control groups and baseline group differences in confounding factors. Despite these limitations, the best designed studies, those comparing patients on ADT to healthy controls, generally suggest that spatial memory might be especially sensitive to the effects of ADT. Critically, to date there is only one study involving random assignment of ADT versus close clinical observation. That study revealed a decrease in verbal memory with ADT, but was limited in sample size and did not include a measure of spatial memory. A recent observational study revealed no substantial evidence of cognitive impairment with ADT, even in the domain of verbal memory. Like the randomized study, however, this large observational study lacked a measure of spatial memory. Overall, the studies with the best controls suggest a potential negative impact of ADT on spatial memory, and perhaps verbal memory, and a need for continued investigation of the impact of ADT on cognition, particularly in these two cognitive domains

Neural correlates of semantic associations in patients with schizophrenia

Patients with schizophrenia have semantic processing disturbances leading to expressive language deficits (formal thought disorder). The underlying pathology has been related to alterations in the semantic network and its neural correlates. Moreover, crossmodal processing, an important aspect of communication, is impaired in schizophrenia. Here we investigated specific processing abnormalities in patients with schizophrenia with regard to modality and semantic distance in a semantic priming paradigm. Fourteen patients with schizophrenia and fourteen demographically matched controls made visual lexical decisions on successively presented word-pairs (SOA = 350 ms) with direct or indirect relations, unrelated word-pairs, and pseudoword-target stimuli during fMRI measurement. Stimuli were presented in a unimodal (visual) or crossmodal (auditory-visual) fashion. On the neural level, the effect of semantic relation indicated differences (patients > controls) within the right angular gyrus and precuneus. The effect of modality revealed differences (controls > patients) within the left superior frontal, middle temporal, inferior occipital, right angular gyri, and anterior cingulate cortex. Semantic distance (direct vs. indirect) induced distinct activations within the left middle temporal, fusiform gyrus, right precuneus, and thalamus with patients showing fewer differences between direct and indirect word-pairs. The results highlight aberrant priming-related brain responses in patients with schizophrenia. Enhanced activation for patients possibly reflects deficits in semantic processes that might be caused by a delayed and enhanced spread of activation within the semantic network. Modality-specific decreases of activation in patients might be related to impaired perceptual integration. Those deficits could induce and increase the prominent symptoms of schizophrenia like impaired speech processing