spatial cognition

Previous studies have shown promising findings on effectiveness of noisy Galvanic Vestibular Stimulation (nGVS) in various cognitive disorders. The connections of the vestibular system with the hippocampus has been proven. Here we investigated the effect of vestibular galvanic stimulation on the improvement of spatial learning and memory of rats.

Twelve Wistar rats were randomly divided into control and nGVS groups. The nGVS group underwent 30-minute sessions of stimulation at sub-threshold levels for a duration of fourteen days. Following the intervention, both groups underwent assessments of cognitive indices through the Morris water maze task, hippocampal neuronal spike rate by Single-Unit Recording (SUR) and the concentrations of c-fos protein in the hippocampus were measured using ELISA device.

The nGVS group exhibited a significant difference compared to the control group in both the time taken to reach the target platform and the percentage of time spent in the goal quarter during the Morris water maze test. The nGVS treatment significantly enhanced spike rate of hippocampal dentate gyrus (p<0.01) compared to the control group. Additionally, c-fos protein concentrations were increased in the nGVS (5.833) than the control group (4.126), (p<0.001).

According to the obtained results, nGVS plays a role in improving spatial memory, and a longer duration of intervention is suggested to achieve more obvious improvement results.

Hepatic encephalopathy (HE) is a neuropsychiatric syndrome that causes brain disturbances. Thymoquinone (TQ) has a wide spectrum of activities such as antioxidant, anti-inflammatory, and anticancer. This study aimed to evaluate the effects of TQ on spatial memory and hippocampal long-term potentiation (LTP) in rats with thioacetamide (TAA)-induced liver injury and hepatic encephalopathy. Adult male Wistar rats were divided into six groups randomly: 1) Control; 2) HE, received TAA (200 mg/kg); 3-5) Treated groups (HE+TQ5, HE+TQ10, and HE+TQ20). TQ (5, 10, and 20 mg/kg) was injected intraperitoneally (IP) for 12 consecutive days from day 18 to 29. Subsequently, spatial memory performance was evaluated by the Morris water maze paradigm and hippocampal LTP was recorded from the dentate gyrus (DG) region. Activity levels of Malondialdehyde (MDA) and superoxide dismutase (SOD) were measured in the hippocampal tissue. Data showed that the hippocampal content of MDA was increased while SOD activities were decreased in TAA-induced HE. TQ treatment significantly improved spatial memory and LTP. Moreover, TQ restored the levels of MDA and SOD activities in the hippocampal tissue in HE rats. Our data confirm that TQ could attenuate cognitive impairment and improve LTP deficit by modulating the oxidative stress parameters in this model of HE, which leads to impairment of spatial cognition and LTP deficit. Thus, these results suggest that TQ may be a promising agent with positive therapeutic effects against liver failure and HE defects.

The competence to perceive the spatial surroundings is vital to tasks ranging from catching nearby objects to complex navigation through an unknown environment. Yet, many studies testing the functioning of visually impaired people in spatial tasks reported mixed results. Although the role of vision still remains critical in various aspects for such activities, vision experience is not necessarily needed for productive spatial cognition. The neural plasticity of the remaining modalities can reorganize the human brain to compensate the effects of blindness in order to efficiently implement the spatial cognition for navigating. The ability to discern the true nature of the human spatial cognition will lead to potential precise applications in the development of aids for visually impaired people.

Centella asiatica extract on cognition and hippocampal pathology of mild chronic cerebral hypoperfusion (CCH) that was induced by permanent right common carotid artery occlusion (RCO) in rats.
Sixty-four male Sprague-Dawley rats were randomly divided into four groups of Sham-veh, Sham-C. asiatica, RCO-veh and RCO-C. asiatica, which were further divided into short-term and long-term CCH induction. Oral treatments with 20 mg/kg C. asiatica initiated 24 hours and 12 months after CCH and continued for 14 consecutive days. According to the cognition and histopathological evaluation period, the experiment was divided into 2 sets of either 2 or 12 months of CCH.
Results showed that 2-month CCH induced learning flexibility deficit associated with CA1 neuronal damage and internal capsule (IC) astroglia activation. Long-lasting (12 months) mild CCH induced spatial learning, memory and flexibility deficits associated with progressive dorsal hippocampal damage. Treatment with 20 mg/kg of C. asiatica improved learning flexibility deficit after 2 and 12 months of CCH. C. asiatica ameliorated neuronal damage in the dorsal hippocampus at 2 months of CCH when given 24 hours after CCH onset. Treatment with C. asiatica after 12 months of cerebral blood flow reduction improved memory and learning flexibility deficits and was associated with the dentate gyrus neuronal damage reduction.
Our finding indicates the therapeutic potential of C. asiatica either when given immediately after ischemic insult or when administered one year after ischemic insult, in a CCH rat model.

Parallel mathematical descriptions of behavioral structures across species are not necessarily associated with parallel cognitive outcomes. The present discussion provides an analysis of the mechanisms that might be involved in generating such superficial parallel behaviours and sketches a theoretical framework to outline a possible way of understanding cognitive superiority in humans as a qualitative difference. Piaget’s version of recapitulation theory is the focus of this study, which will be presented in three main sections: first a “thought experiment” will demonstrate that Piaget’s version of recapitulation leads to a logical difficulty in explaining cognitive outcomes based on parallel behaviors across species. Then, examples of different brain areas that might be involved in generating such superficial parallel structures in spatial navigation will be discussed and finally a theoretical framework will be proposed to demonstrate how a redirection from Piaget’s focus on the behaviour as the “motor of evolution” to a consideration of the division of labour in the brain would potentially explain the superior cognitive outcomes in humans based on the abstraction of computational patterns generated by neuronal firing in relevant brain areas..