Although contemporary socio-cultural changes dramatically increased fathers' involvement in childrearing, little is known about the brain basis of human fatherhood, its comparability with the maternal brain, and its sensitivity to caregiving experiences. We measured parental brain response to infant stimuli using functional MRI, oxytocin, and parenting behavior in three groups of parents (n = 89) raising their firstborn infant: heterosexual primarycaregiving mothers (PC-Mothers), heterosexual secondary-caregiving fathers (SC-Fathers), and primary-caregiving homosexual fathers (PC-Fathers) rearing infants without maternal involvement. Results revealed that parenting implemented a global "parental caregiving" neural network, mainly consistent across parents, which integrated functioning of two systems: the emotional processing network including subcortical and paralimbic structures associated with vigilance, salience, reward, and motivation, and mentalizing network involving frontopolar-medial-prefrontal and temporo-parietal circuits implicated in social understanding and cognitive empathy. These networks work in concert to imbue infant care with emotional salience, attune with the infant state, and plan adequate parenting. PC-Mothers showed greater activation in emotion processing structures, correlated with oxytocin and parent-infant synchrony, whereas SC-Fathers displayed greater activation in cortical circuits, associated with oxytocin and parenting. PC-Fathers exhibited high amygdala activation similar to PC-Mothers, alongside high activation of superior temporal sulcus (STS) comparable to SC-Fathers, and functional connectivity between amygdala and STS. Among all fathers, time spent in direct childcare was linked with the degree of amygdala-STS connectivity. Findings underscore the common neural basis of maternal and paternal care, chart brain-hormone-behavior pathways that support parenthood, and specify mechanisms of brain malleability with caregiving experiences in human fathers.mothering | parent-infant interaction | alloparental care | transition to parenthood | social brain

Combining elaborate neurophysiological assessment, tractography-based neuronavigation, and updated IOUS images provided accurate localization of the CSTs and enabled the safe resection of tumors approximating these tracts. This is the first attempt to evaluate the distance from the CSTs using the threshold of subcortical monopolar stimulation with real-time IOUS for the correction of brain shift. The linear correlation between the distance to the CSTs and the threshold of subcortical stimulation producing a motor response provides an intraoperative technique to better preserve motor function.

Numerous neuroimaging studies have implicated default mode network (DMN) involvement in both internally driven processes and memory. Nevertheless, it is unclear whether memory operations reflect a particular case of internally driven processing or alternatively involve the DMN in a distinct manner, possibly depending on memory type. This question is critical for refining neurocognitive memory theorem in the context of other endogenic processes and elucidating the functional significance of this key network. We used functional MRI to examine DMN activity and connectivity patterns while participants overtly generated words according to nonmnemonic (phonemic) or mnemonic (semantic or episodic) cues. Overall, mnemonic word fluency was found to elicit greater DMN activity and stronger within-network functional connectivity compared with nonmnemonic fluency. Furthermore, two levels of functional organization of memory retrieval were shown. First, across both mnemonic tasks, activity was greater mainly in the posterior cingulate cortex, implying selective contribution to generic aspects of memory beyond its general involvement in endogenous processes. Second, parts of the DMN showed distinct selectivity for each of the mnemonic conditions; greater recruitment of the anterior prefrontal cortex, retroesplenial cortex, and hippocampi and elevated connectivity between anterior and posterior medial DMN nodes characterized the semantic condition, whereas increased recruitment of posterior DMN components and elevated connectivity between them characterized the episodic condition. This finding emphasizes the involvement of DMN elements in discrete aspects of memory retrieval. Altogether, our results show a specific contribution of the DMN to memory processes, corresponding to the specific type of memory retrieval.free recall | memory search | word fluency T he default mode network (DMN) is known to play a central role in internally based processes, including self-referential operations (1-4), internal mentation (5), and unconstrained thinking (6, 7). Additionally, during the past decades, the DMN has consistently been implicated in both semantic (8, 9) and episodic (10-13) memory processes. However, despite the fact that internal operations are inherent to many, if not all, mnemonic tasks, the unique contributions of the DMN to memory operations beyond its more general role in nonmnemonic internally based processes have not been sufficiently addressed thus far.One example of an internally based mnemonic process is mental search, which plays a central role in memory retrieval (14). Although a significant contribution of the DMN to memory search has been shown (12, 15), it is yet unclear whether this contribution merely reflects the DMN's involvement in nonspecific internal direction of attention or rather, a specific role for the DMN in mnemonic search processes. Direct comparison of DMN recruitment during memory search with its recruitment during nonmnemonic internal search operations may shed light on this matter. This questi...