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Fulltext Analysis of motorcyclist riding behaviour on speed table

Yuen CW, Karim MR, Saifizul A

ScientificWorldJournal, 2014;2014:236396.
PMID: 24991638 DOI: 10.1155/2014/236396

This paper focuses on the study of the change of various types of riding behaviour, such as speed, brake force, and throttle force applied, when they ride across the speed table. An instrumented motorcycle equipped with various types of sensor, on-board camera, and data logger was used in acquiring the traffic data in the research. Riders were instructed to ride across two speed tables and the riding data were then analyzed to study the behaviour change from different riders. The results from statistical analysis showed that the riding characteristics such as speed, brake force, and throttle force applied are influenced by distance from hump, riding experience, and travel mileage of riders. Riders tend to apply higher brake intensity at distance point 50 m before the speed table and release the braking at point -10 m after the hump. In short, speed table has different rates of influence towards riding behaviour on different factors, such as distance from hump and different riders' attributes.

Matched MeSH terms: Spatial Behavior*
Spatial memory performance of Wistar rats exposed to mobile phone

Narayanan SN, Kumar RS, Potu BK, Nayak S, Mailankot M

Clinics (Sao Paulo), 2009;64(3):231-4.
PMID: 19330250

INTRODUCTION: With the tremendous increase in number of mobile phone users world wide, the possible risks of this technology have become a serious concern.
OBJECTIVE: We tested the effects of mobile phone exposure on spatial memory performance.
MATERIALS AND METHODS: Male Wistar rats (10-12 weeks old) were exposed to 50 missed calls/day for 4 weeks from a GSM (900/1800 MHz) mobile phone in vibratory mode (no ring tone). After the experimental period, the animals were tested for spatial memory performance using the Morris water maze test.
RESULTS: Both phone exposed and control animals showed a significant decrease in escape time with training. Phone exposed animals had significantly (approximately 3 times) higher mean latency to reach the target quadrant and spent significantly (approximately 2 times) less time in the target quadrant than age- and sex-matched controls.
CONCLUSION: Mobile phone exposure affected the acquisition of learned responses in Wistar rats. This in turn points to the poor spatial navigation and the object place configurations of the phone-exposed animals.

Matched MeSH terms: Spatial Behavior/physiology; Spatial Behavior/radiation effects*
Space, repetition and collective interlocution: Psychiatric interviews in a Borneo longhouse

Barrett RJ

Commun Med, 2004;1(1):25-34.
PMID: 16808686

An analysis is presented of psychiatric research interviews conducted among the Iban, a longhouse dwelling people of Sarawak, Malaysia. It draws on transcripts of interviews recorded in the course of carrying out research into schizophrenia in this group. The article examines three different interview spaces within the longhouse--public, family, and private--in order to explore the interplay between ethnographic context and interview conversation. The public setting is notable for the number of relatives who join in and transform the communication from dyadic to collective interlocution; the role of repetition in recruiting them into the conversation is explored. Indirect contrast is the private space, which allows for a level of confidentiality commensurate with Western psychiatric research practice. Intermediate between the two is the family space. The communicative forms that correspond to these settings influence the way symptoms of schizophrenia are experienced and expressed in the Iban. Implications for the practice of psychiatry cross-culturally are examined.

Matched MeSH terms: Spatial Behavior*
A Bayesian analysis of the temporal change of local density of proboscis monkeys: implications for environmental effects on a multilevel society

Matsuda I, Kubo T, Tuuga A, Higashi S

Am J Phys Anthropol, 2010 Jun;142(2):235-45.
PMID: 20091847 DOI: 10.1002/ajpa.21218

To understand the effects of environmental factors on a social system with multilevel society in proboscis monkey units, the temporal change of the local density of sleeping sites of monkeys was investigated along the Menanggul river from May 2005 to 2006 in Malaysia. Proboscis monkeys typically return to riverside trees for night sleeping. The sleeping site locations of a one-male unit (BE-unit) were recorded and the locations of other one-male and all-male units within 500 m of the BE-unit were verified. In addition, environmental factors (food availability, the water level of the river, and the river width) and copulation frequency of BE-unit were recorded. From the analyses of the distance from the BE-unit to the nearest neighbor unit, no spatial clumping of the sleeping sites of monkey units on a smaller scale was detected. The results of a Bayesian analysis suggest that the conditional local density around the BE-unit can be predicted by the spatial heterogeneity along the river and by the temporal change of food availability, that is, the local density of monkey units might increase due to better sleeping sites with regard to predator attacks and clumped food sources; proboscis monkeys might not exhibit high-level social organization previously reported. In addition, this study shows the importance of data analysis that considers the effects of temporal autocorrelation, because the daily measurements of longitudinal data on monkeys are not independent of each other.

Matched MeSH terms: Spatial Behavior*
Baclofen blocks the acquisition and expression of mitragynine-induced conditioned place preference in rats

Yusoff NHM, Mansor SM, Müller CP, Hassan Z

Behav Brain Res, 2018 06 01;345:65-71.
PMID: 29499286 DOI: 10.1016/j.bbr.2018.02.039

Mitragynine is the major alkaloid found in the leaves of M. speciosa Korth (Rubiaceae), a plant that is native to Southeast Asia. This compound has been used, either traditionally or recreationally, due to its psychostimulant and opioid-like effects. Recently, mitragynine has been shown to exert conditioned place preference (CPP), indicating the rewarding and motivational properties of M. speciosa. Here, the involvement of GABAB receptors in mediating mitragynine reward is studied using a CPP paradigm in rats. First, we examined the effects of GABAB receptor agonist baclofen (1.25, 2.5 and 5 mg/kg) on the acquisition of mitragynine (10 mg/kg)-induced CPP. Second, the involvement of GABAB receptors in the expression of mitragynine-induced CPP was tested. We found that the acquisition of mitragynine-induced CPP could be blocked by higher doses (2.5 and 5 mg/kg) of baclofen. Baclofen at a high dose inhibited locomotor activity and caused a CPP. Furthermore, we found that baclofen (2.5 and 5 mg/kg) also blocked the expression of mitragynine-induced CPP. These findings suggest that both, the acquisition and expression of mitragynine's reinforcing properties is controlled by the GABAB receptor.

Matched MeSH terms: Spatial Behavior/drug effects; Spatial Behavior/physiology
Fulltext Impact of individual demographic and social factors on human-wildlife interactions: a comparative study of three macaque species

Balasubramaniam KN, Marty PR, Samartino S, Sobrino A, Gill T, Ismail M, et al.

Sci Rep, 2020 12 15;10(1):21991.
PMID: 33319843 DOI: 10.1038/s41598-020-78881-3

Despite increasing conflict at human-wildlife interfaces, there exists little research on how the attributes and behavior of individual wild animals may influence human-wildlife interactions. Adopting a comparative approach, we examined the impact of animals' life-history and social attributes on interactions between humans and (peri)urban macaques in Asia. For 10 groups of rhesus, long-tailed, and bonnet macaques, we collected social behavior, spatial data, and human-interaction data for 11-20 months on pre-identified individuals. Mixed-model analysis revealed that, across all species, males and spatially peripheral individuals interacted with humans the most, and that high-ranking individuals initiated more interactions with humans than low-rankers. Among bonnet macaques, but not rhesus or long-tailed macaques, individuals who were more well-connected in their grooming network interacted more frequently with humans than less well-connected individuals. From an evolutionary perspective, our results suggest that individuals incurring lower costs related to their life-history (males) and resource-access (high rank; strong social connections within a socially tolerant macaque species), but also higher costs on account of compromising the advantages of being in the core of their group (spatial periphery), are the most likely to take risks by interacting with humans in anthropogenic environments. From a conservation perspective, evaluating individual behavior will better inform efforts to minimize conflict-related costs and zoonotic-risk.

Matched MeSH terms: Spatial Behavior
Opioid receptors mediate the acquisition, but not the expression of mitragynine-induced conditioned place preference in rats

Yusoff NHM, Mansor SM, Müller CP, Hassan Z

Behav Brain Res, 2017 08 14;332:1-6.
PMID: 28559179 DOI: 10.1016/j.bbr.2017.05.059

Mitragynine is the main psychoactive ingredient of the herbal drug preparation Kratom (Ketum), derived from the plant Mitragyna speciosa. Kratom is a widely abused drug in Southeast Asian and has a psychostimulant profile at low-medium doses, while high doses have opioidergic effects. Mitragynine was shown to possess opiate receptor affinity. However, its role in the behavioural effects of mitragynine is unclear. Here we asked whether the reinforcing effects of mitragynine are mediated by opiate receptors using a conditioned place preference (CPP) paradigm in rats. In the first experiment we tested the effects of the opiate receptor antagonist naloxone (0.1, 0.3 and 1.0mg/kg) on the acquisition of mitragynine (10mg/kg)-induced CPP. In the second experiment, we tested the involvement of opiate receptors in the expression of mitragynine-induced CPP in rats. We found that naloxone suppresses the acquisition of mitragynine-induced CPP. This effect was already evident at a dose of naloxone (0.1mg/kg) which, by itself, had no conditioned place aversion (CPA) effect. Higher doses of naloxone induced a CPA and blocked mitragynine-induced CPP. In contrast, naloxone had no effect on the expression of mitragynine-induced CPP. These findings suggest that the acquisition, but not the expression of the reinforcing effects of mitragynine is mediated by opiate receptors.

Matched MeSH terms: Spatial Behavior/drug effects*; Spatial Behavior/physiology
Fulltext Omega 3 polyunsaturated fatty acid improves spatial learning and hippocampal peroxisome proliferator activated receptors (PPARα and PPARγ) gene expression in rats

Hajjar T, Meng GY, Rajion MA, Vidyadaran S, Othman F, Farjam AS, et al.

BMC Neurosci, 2012;13:109.
PMID: 22989138 DOI: 10.1186/1471-2202-13-109

This study examined the effects of dietary polyunsaturated fatty acids (PUFA) as different n-6: n-3 ratios on spatial learning and gene expression of peroxisome- proliferator-activated receptors (PPARs) in the hippocampus of rats. Thirty male Sprague-Dawley rats were randomly allotted into 3 groups of ten animals each and received experimental diets with different n-6: n-3 PUFA ratios of either 65:1, 22:1 or 4.5:1. After 10 weeks, the spatial memory of the animals was assessed using the Morris Water Maze test. The expression of PPARα and PPARγ genes were determined using real-time PCR.

Matched MeSH terms: Spatial Behavior/drug effects*
Conceptual Design of Haptic-Feedback Navigation Device for Individuals with Alzheimer's Disease

Che Me R, Biamonti A, Mohd Saad MR

Stud Health Technol Inform, 2015;217:195-203.
PMID: 26294473

Wayfinding ability in older adults with Alzheimer's disease (AD) is progressively impaired due to ageing and deterioration of cognitive domains. Usually, the sense of direction is deteriorated as visuospatial and spatial cognition are associated with the sensory acuity. Therefore, navigation systems that support only visual interactions may not be appropriate in case of AD. This paper presents a concept of wearable navigation device that integrates the haptic-feedback technology to facilitate the wayfinding of individuals with AD. The system provides the simplest instructions; left/right using haptic signals, as to avoid users' distraction during navigation. The advantages of haptic/tactile modality for wayfinding purpose based on several significant studies are presented. As preliminary assessment, a survey is conducted to understand the potential of this design concept in terms of (1) acceptability, (2) practicality, (3) wearability, and (4) environmental settings. Results indicate that the concept is highly acceptable and commercially implementable. A working prototype will be developed based on the results of the preliminary assessment. Introducing a new method of navigation should be followed by continuous practices for familiarization purpose. Improved navigability allows the good performance of activities of daily living (ADLs) hence maintain the good quality of life in older adults with AD.

Matched MeSH terms: Spatial Behavior
Fulltext Mitragynine attenuates withdrawal syndrome in morphine-withdrawn zebrafish

Khor BS, Jamil MF, Adenan MI, Shu-Chien AC

PLoS One, 2011;6(12):e28340.
PMID: 22205946 DOI: 10.1371/journal.pone.0028340

A major obstacle in treating drug addiction is the severity of opiate withdrawal syndrome, which can lead to unwanted relapse. Mitragynine is the major alkaloid compound found in leaves of Mitragyna speciosa, a plant widely used by opiate addicts to mitigate the harshness of drug withdrawal. A series of experiments was conducted to investigate the effect of mitragynine on anxiety behavior, cortisol level and expression of stress pathway related genes in zebrafish undergoing morphine withdrawal phase. Adult zebrafish were subjected to two weeks chronic morphine exposure at 1.5 mg/L, followed by withdrawal for 24 hours prior to tests. Using the novel tank diving tests, we first showed that morphine-withdrawn zebrafish display anxiety-related swimming behaviors such as decreased exploratory behavior and increased erratic movement. Morphine withdrawal also elevated whole-body cortisol levels, which confirms the phenotypic stress-like behaviors. Exposing morphine-withdrawn fish to mitragynine however attenuates majority of the stress-related swimming behaviors and concomitantly lower whole-body cortisol level. Using real-time PCR gene expression analysis, we also showed that mitragynine reduces the mRNA expression of corticotropin releasing factor receptors and prodynorphin in zebrafish brain during morphine withdrawal phase, revealing for the first time a possible link between mitragynine's ability to attenuate anxiety during opiate withdrawal with the stress-related corticotropin pathway.

Matched MeSH terms: Spatial Behavior/drug effects