Taken together, our neuronal and behavioral findings demonstrate that:
- High childhood stress and trauma
- Is related to lower MPFC activation during both rest and the self-oriented task.
- This is behaviorally manifested as an abnormal shift from internally to externally guided decision making, even in situations where internal guidance is required.
This preliminary study was conducted to investigate the relations between childhood stress and trauma and the (brain) MPFC function during a resting state and self-oriented task. Our obtained NIRS data have revealed that:
- Childhood stress and trauma is associated with decreased activation within the surface regions of MPFC during rest and during the self-oriented task
- In addition, childhood stress and trauma and the decreased activation within the MPFC during the self-oriented task was associated with a tendency to make a decision based on a salient external criterion during the self-oriented task.
This study is expected to be of great interest in the field of childhood stress and trauma itself in that it provides evidence about the relations among childhood stress and trauma, resting-state brain activity, task induced brain activity, and behavioral tendencies.
Based on these notions, a possible explanation underlying these correlations is that participants with a high degree of childhood stress and trauma cannot shift to refer to their own internal criteria during self-oriented tasks because changes in their (brains) do not allow them to make the shift from external to internal. They are stuck in the external, which makes it appear as though they avoid making decisions based on their own internal criteria to eliminate anxiety about one’s own decision. This possibility seems more plausible in light of the observations that childhood stress and trauma induces anxiety-related behaviors in adulthood.
Given that childhood stress and trauma disrupts a balance between LPFC and MPFC function leading to biasing decisions based on internal criteria during the self-oriented task,
Taken together, it is feasible that the participants with a high degree of the childhood stress and trauma cannot shift to refer to their own internal criteria during self-oriented tasks because their MPFC (brains) does not allow them to make the shift from external to internal, especially in the case that the resting-state activity in LPFC was enhanced…
How are our findings related to the self?…Our data hint that such comparing and relating against an internal standard, the self, is deficient in participant with high childhood stress and trauma, which raises two questions related to mediating neuronal mechanisms and related to the presupposed concept of the self.
Our data contribute to the first question. In addition to the task-related activity during color-preference judgment, childhood stress and trauma were predicted by the degree of resting-state activity. This suggests some kind of encoding (or representation) of self-related information (about the self) in the resting-state activity itself; this is well in line with previous findings that observed neural overlap (or even prediction) between resting-state activity and self-related activity…
The present study contributes here in that it suggests this self-related information in the resting state to be susceptible to, at least in part, childhood stress and trauma that seems to affect the self (or better its encoding or representation in the resting state) directly. That leads us directly to the second question: what concept of self do we presuppose here? The resting-state activity itself, by definition:
- Shows no kind of cognitive activity related to specific stimuli or task
- It also shows no sensory, motor, or affective neural activity.
- Consequently, the self that is encoded or represented in the resting state cannot be described as sensorimotor self, cognitive self, or social self.
- Instead, the self that is encoded in the resting state and susceptible to early stressful life events must be described conceptually independent of any specific sensory, motor, affective, cognitive, or social contents
- Instead it is apparently more like some kind of structure or organization that serves as the internal standard or reference for subsequent comparing and relating of stimuli like colors that is color preference. Accordingly, our findings suggest a structure or organization-based concept of self which is well compatible with approaches in both neurophilosophy and the concept of the ego in neuropsychoanalysis.
Despite the importance of these data for revealing the relation between childhood stress and trauma and brain function, these findings leave several questions unresolved… These results tempt us to advance the following hypothesis:
- Childhood stress and trauma results in increased LPFC during rest and decreased MPFC during rest and self-oriented task later in life.
- Because of these characteristics of neural activities, people with childhood stress and trauma make decisions based on a salient external criterion even when they must make a decision based on their own internal criteria.
This hypothesis, however, remains speculative in the absence of data to corroborate these causal relations…This result lends further support to the notion that childhood stress and trauma is associated with attenuated or decreased MPFC function. However, we must be careful about this discrepancy to interpret the correlation result: it is possible that the regions showing a significant difference between these two tasks were dissociated from the regions showing correlation with the CATS score. Additional studies using fMRI must be undertaken to examine this possibility.”
The Degree Of Early Life Stress Predicts Decreased Medial Prefrontal Activations And The Shift From Internally To Externally Guided Decision Making: An Exploratory Nirs Study During Resting State And Self-Oriented Task Takashi Nakao1* Excerpted and edited from full article here