551 research outputs found
On the path integration system of insects: there and back again
Navigation is an essential capability of animate organisms and robots. Among animate organisms of particular interest are insects because they are capable of a variety of navigation competencies solving challenging problems with limited resources, thereby providing inspiration for robot navigation.
Ants, bees and other insects are able to return to their nest using a navigation strategy known as path integration. During path integration, the animal maintains a running estimate of the distance and direction to its nest as it travels. This estimate, known as the `home vector', enables the animal to return to its nest.
Path integration was the technique used by sea navigators to cross the open seas in the past. To perform path integration, both sailors and insects need access to two pieces of information, their direction and their speed of motion over time. Neurons encoding the heading and speed have been found to converge on a highly conserved region of the insect brain, the central complex. It is, therefore, believed that the central complex is key to the computations pertaining to path integration.
However, several questions remain about the exact structure of the neuronal circuit that tracks the animal's heading, how it differs between insect species, and how the speed and direction are integrated into a home vector and maintained in memory. In this thesis, I have combined behavioural, anatomical, and physiological data with computational modelling and agent simulations to tackle these questions.
Analysis of the internal compass circuit of two insect species with highly divergent ecologies, the fruit fly Drosophila melanogaster and the desert locust Schistocerca gregaria, revealed that despite 400 million years of evolutionary divergence, both species share a fundamentally common internal compass circuit that keeps track of the animal's heading. However, subtle differences in the neuronal morphologies result in distinct circuit dynamics adapted to the ecology of each species, thereby providing insights into how neural circuits evolved to accommodate species-specific behaviours.
The fast-moving insects need to update their home vector memory continuously as they move, yet they can remember it for several hours. This conjunction of fast updating and long persistence of the home vector does not directly map to current short, mid, and long-term memory accounts. An extensive literature review revealed a lack of available memory models that could support the home vector memory requirements.
A comparison of existing behavioural data with the homing behaviour of simulated robot agents illustrated that the prevalent hypothesis, which posits that the neural substrate of the path integration memory is a bump attractor network, is contradicted by behavioural evidence.
An investigation of the type of memory utilised during path integration revealed that cold-induced anaesthesia disrupts the ability of ants to return to their nest, but it does not eliminate their ability to move in the correct homing direction. Using computational modelling and simulated agents, I argue that the best explanation for this phenomenon is not two separate memories differently affected by temperature but a shared memory that encodes both the direction and distance.
The results presented in this thesis shed some more light on the labyrinth that researchers of animal navigation have been exploring in their attempts to unravel a few more rounds of Ariadne's thread back to its origin. The findings provide valuable insights into the path integration system of insects and inspiration for future memory research, advancing path integration techniques in robotics, and developing novel neuromorphic solutions to computational problems
2023-2024 Graduate School Catalog
You and your peers represent more than 67 countries and your shared scholarship spans 140 programs - from business administration and biomedical engineering to history, horticulture, musical performance, marine science, and more. Your ideas and interests will inform public health, create opportunities for art and innovation, contribute to the greater good, and positively impact economic development in Maine and beyond
30th European Congress on Obesity (ECO 2023)
This is the abstract book of 30th European Congress on Obesity (ECO 2023
2015 GREAT Day Program
SUNY Geneseo’s Ninth Annual GREAT Day.https://knightscholar.geneseo.edu/program-2007/1009/thumbnail.jp
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Rulemaking as Play: A Transdisciplinary Inquiry about Virtual Worldmaking
In the age of computing, we rely on software to manage our days, from the moment we wake up until we go to sleep. Software predicts the future based on actualized data from the past. It produces procedures instead of experiences and solutions instead of care. Software systems tend to perpetuate a normalized state of equilibrium. Their application in social media, predictive policing, and social profiling is increasingly erasing diversity in culture and identity. Our immediate reality is narrowing towards cultural conventions shared among the powerful few, whose voices directly influence contemporary digital culture.
On the other hand, computational collective intelligence can sometimes generate emergent forces to counter this tendency and force software systems to open up. Historically, artists from different artistic moments have adopted collaborative making to redefine the boundary of creative expression. Video Gaming, especially open-world simulation games, is rapidly being adopted as an emerging form of communication, expression, and self-organization.
How can gaming conventions such as Narrative Emergence, Hacking, and Modding help us understand collective play as countering forces against the systematic tendency of normalization? How can people from diverse backgrounds come together to contemplate, make, and simulate rules and conditions for an alternative virtual world? What does it mean to design and virtually inhabit a world where rules are rewritten continuously by everyone, and no one is in control
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