Rowena Kong

Hyperthermia-induced vasoconstriction is a paradoxical physiological phenomenon that has limited explanation and exploration in research, despite being observed in clinical case studies. The bodily response of vasoconstriction and vasodilation to increased heat loss and gain respectively work on the principle that heat transfer through the amount of vascular surface area exposed can be moderated in order to be minimised or maximised. Hyperthermia-induced vasoconstriction likely transitions from the break point of maximal limit of vasodilation to counter extreme heat loss beyond this point and to mitigate the potential detrimental effect in arterial pressure disturbance by extreme temperature condition. We also propose an additional explanation of this physiological counter mechanism based on the perspective of body core-peripheral steep temperature gradient reduction during hyperthermia or significant temperature increase, and a spontaneous tendency to avoid unstable blood pressure perturbation.

The amygdala is a crucial brain region responsible for emotional processing and fear conditioning and learning. The major classes of neuroreceptors and pathways present in this region are significantly engaged in such functions that extend to memory associations, cognition, appraisal and responsiveness to emotional and fearful stimuli. There is evidence of a rich integration of neurofunctions and connection with the rest of the human physiological system. Gender differences in amygdala reactivity to stimuli are also discussed to aid understanding of external factors that may play a role in causation of such differences.

In a recent case-control study by Zimny et al. (2021), the development of unruptured cerebral artery aneurysm can be reasonably traced to the combined factor of high wall shear stress and wall shear stress gradient. In addition, regions of bifurcation apices with such factor of significant wall shear stress are critical in aneurysm formation. A consideration of directional and spatial changes in opposition against the inertia and seamless hemodynamic blood flow in approaching the juncture of bifurcation apex that increase interaction of contact forces between arterial walls and blood volume may aid in further discussion of causality.

The paradoxical phenomena of hyperthermia-induced vasoconstriction, hyperthermia-induced hypothermia, and hyperthermia induced arterial vasoconstriction have been observed in animal heatstroke clinical case studies. We attempt to explain the basic mechanism behind such findings in terms of the principle of body heat conservation and natural countermeasure against heat exposure through reduction in the extent of vascular surface area exposed. Hyperthermia-induced vasoconstriction is a paradoxical physiological phenomenon that has limited explanation and exploration in research, despite being observed in clinical case studies. The bodily response of vasoconstriction and vasodilation to increased heat loss and gain work on the principle that heat transfer through the amount of vascular surface area exposed can be moderated in order to be minimised or maximised. Hyperthermia-induced vasoconstriction likely transitions from the break point of maximal limit of vasodilation to counter further rapid heat loss beyond this point. We also propose an explanation of this physiological counter mechanism from the perspective of body core-peripheral steep temperature gradient reduction during hyperthermia or extreme temperature conditions and a spontaneous tendency to avoid unstable blood pressure perturbation. One study which examined the outcome of heating a rabbit's carotid artery produced graded vasoconstriction which is proportional to temperature increase (Mustafa, Thulesius, & Ismael, 2004). These interesting results point out a spontaneous physiological counteractive measure to minimise organ and/or arterial surface area heat exposure through extreme vasodilation by inducing vasoconstriction to counter against persistent excessive heat loss from rapidly increasing temperature of internal organ(s) to the ambient environment, as well as to restore and re-elevate the simultaneous significant arterial blood pressure reduction due to extreme heat gain.

Gallbladder disease commonly affects the general population of Western developed nations and the standard surgical treatment of laparoscopic cholecystectomy normally follows severe cases of this condition. However, the negative health and life quality consequences of this standard line of treatment are lesser known and stand the chance of being taken lightly by healthcare professionals. Complications include bile duct injury, dropped gallstones and a second open invasive surgery, of which could be life threatening for some rare cases. It is, therefore, necessary to highlight the limitations of such a procedure and the need for improvement and widening of the range of treatment options for vulnerable members of the patient population. Additionally, here is a brief overview introduction of a new procedure called endoscopic ultrasound guided gallbladder drainage with promising success rates that can be a potentially feasible alternative to traditional surgical procedures to offer gallbladder disease patients.

The possible significance of compromised exposure to positive stimuli during an individual's early childhood could contribute to impoverished positive memory development and subsequently dysregulated emotional responses to such valence of stimuli in adulthood. This could potentially explain dampened positive emotional responses of depressed individuals as reported in imaging studies of the brain's mesolimbic reward pathways. This paper provides emphasis and suggestions for a preliminary exploration of positive cartoon stimuli as a new tool in therapeutic targets for depression treatment and research that cater to a subgroup of depressive individuals who had experienced childhood trauma and stressful episodes as their primary causes of the disorder. Cartoon stimuli as a form of visual and interactive therapy may provide a compensatory and restorative component for the emotional losses and insults on an otherwise healthy childhood positivity required for normal and balanced neuropsychological development and growth. Unfortunately, such readily available resources for therapy have hardly been considered and utilized. The potential benefit of exposure to cartoon stimuli may extend beyond the method of positive mood induction and further addresses the need for both implicit and explicit comfort, understanding, emotional and situational relatedness that compensate for the lack of such stimulation during an early stressful life. Through evoking childlike positive associations, it is hypothesized that depression could reduce in severity and the threshold for activation of response to positive stimuli and themes lowered, thereby restoring negative and positive mood imbalances.

The paradoxical phenomena of hyperthermia-induced vasoconstriction, hyperthermia- induced hypothermia, and hyperthermia induced arterial vasoconstriction have been observed in animal heatstroke clinical case studies. We attempt to explain the basic mechanism behind such findings in terms of the principle of body heat conservation and natural countermeasure against heat exposure through reduction in the extent of vascular surface area exposed. One study which examined the outcome of heating a rabbit carotid artery produced graded vasoconstriction which is proportional to temperature increase. These interesting results pointed out a spontaneous physiological counteractive measure to minimize organ and/or arterial surface area heat exposure through vasoconstriction which might otherwise prompt excessive heat gain from the ambient environment, or vasodilation, should it occur. When a blood vessel or artery constricts through smooth muscle activation, the amount of vascular surface area being exposed, whether to heat that is external from or internal within the body, is reduced. Since such vasoconstriction is proportional to temperature increase, the speed or rate at which this constriction responds and therefore, the extent of vascular surface area being reduced, may be drastic with extreme means of bodily cooling under a heat wave environment, such as whole-body cold-water bath or shower. The reason being extreme vasoconstriction of both cerebral and peripheral blood vessels, which may result in increased intravascular pressure due to intravascular spatial volume decrease and as an above study concluded, cerebral blood flow decreases and ischemia brain damage.

The functional roles of ventromedial prefrontal cortex (VMPF) and amygdala in affecting emotional processing in decision-making have been raised in support of the somatic marker hypothesis. However, later studies demonstrated challenges to such support based on preserved cognition in the form of reversal learning in VMPF damaged patients tested with a shuffled variant of Iowa Gambling Task. This finding provides implications for cognitive neglect in somatic marker hypothesis with its magnified emphasis on the link between somatic markers and emotion-guided decision-making. It also suggests that cognition could compensate for emotion impairment in the absence of crucial prefrontal cortical region needed for low-risk choice and decision-making. Emotional somatic marker signaling is proposed to be an assistive initiation mechanism for choice decision-making between gains and losses instead of a fixated necessity in the process, and that it works in concert with concurrent conscious knowledge and cognition of the situation, building upon the nature of close connections between the VMPF and other brain region(s).

A previously atypical symptom report of a hospitalized patient experiencing unusual visual broadcasting has been documented but has received minimal attention in the research and clinical field of psychiatry. A preliminary hypothesis is proposed of an implicit mechanism of motivation for action and emotional relief functional significance of elevated cortisol and dopamine correlation, that is loosely based on the concept of stress-induced psychosis and which could have led to a concurrent "visual and thought" psychotic episode. In addition, the implication of the effect of increased dopamine on intracranial pressure and indirectly on cerebral perfusion pressure is briefly discussed. A follow-up on the insight and comprehensive understanding of such atypical and novel symptom as an extension of schizophrenia is warranted.