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Thirteen episodes. One pool. Plenty to argue about.
An audio series for anyone who has ever stared at a probe trial and wondered what it really means.
Image: credit
Put the kettle on. Each episode takes about ten minutes and one big question: how a pool of milky water became a test of memory, why the probe trial matters, what the radial arm, T-maze, Barnes maze and open field add, and which measures tell you what an animal really learned.
Every episode comes with a full transcript, show notes and the papers behind it. Subscribe with the feed, or pick an episode below.
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Episode 1: The pool: how the Morris water maze began
How did a pool of milky water and a hidden platform become one of the most trusted tests of memory?
Episode 2: The probe trial: when the platform disappears
What happens when the platform is taken away, and why is that the real test of spatial memory?
Episode 3: The virtual water maze: the pool test for people
How do you give a person the rodent pool test without the pool, and what changes when you do?
Episode 4: The radial arm maze: eight arms and a running list
What can eight runways and a few food pellets tell us about memory for places?
Episode 5: The open field: what an empty box reveals
How did an empty, brightly lit box become one of the most used and most argued about tests in behaviour?
Episode 6: The T-maze: left, right and a change of mind
Why does a mouse choose the other arm on its second visit, and what does that choice reveal?
Episode 7: The Barnes maze: spatial memory on dry land
How does a bright table ringed with holes test spatial memory without making an animal swim?
Episode 8: Thigmotaxis and search strategies: the shape of a search
Two mice reach the platform in the same time. How can one have learned where it is and the other not?
Episode 9: Proximity and path efficiency: measuring a search well
Why can average distance from the goal be a better measure of memory than counting platform crossings?
Episode 10: Tracking in VR rehabilitation: from the pool to the clinic
What does the evidence say about virtual reality for stroke rehabilitation, and where does tracking fit in?
Episode 11: The Atlantis platform: escape that rises on demand
Why invent a platform that waits under the pool and only rises when the animal stays in the right place?
Episode 12: Floating: when stillness looks like forgetting
Why does a quiet animal in the pool wreck latency, and how do you measure the pause?
Episode 13: Reversal learning: when the platform moves
What happens when the hidden platform moves, and how do you tell a flexible memory from a stubborn one?
Watch
How to see path efficiency ratio in Morris water maze analysis by HVS Image
Path efficiency, one of the stars of episode nine, shown on screen in under three minutes.
Video from the HVS Image channel on YouTube. It's loaded in privacy-enhanced mode and only plays when you press play.
From the journals
Lab notes and measures worth a listen
HVS Image in a teaching lab, a new path-measure note from HVS Image Software Ltd, plus maze studies we'd happily give an episode to. Our rewrites; their originals.
Four pools, Atlantis platforms, and an HVS 2020 tracker
George Mason University's Cognitive and Behavioral Neuroscience facilities page lists a Morris water maze that works with the HVS 2020 system to collect behavioural data for rats and mice. The lab keeps four pools, six, five, four and three feet across, two feet deep, paintable white or black so dark or albino animals can be tracked. Platforms cover Atlantis and moving-platform paradigms, a camera above the maze feeds the HVS imaging system, and large black cues sit on a white surround. The same HVS 2020 set-up can also score open-field behaviour. A rare public inventory that names both the tracker and the Atlantis kit in one place.
Read the original at George Mason University CBNWhen the first stretch of a swim path tells more than the whole trial
A technical note deposited on Zenodo by HVS Image Software Ltd defines the Baker-Hawthorne Direct Path Measures for Morris water maze analysis: how to implement them, how to read them, where they fail, and when to use them. The point is to catch different forms of early, goal-directed navigation toward the target or its immediate vicinity, detail that whole-trial scores can bury. The same principles are meant to travel from rodent pools to virtual reality spatial tasks in humans. Open access under DOI 10.5281/zenodo.21870805.
Zenodo
Read the original at ZenodoExercise order matters, and BDNF doesn't tell the whole story
Forty male Wistar rats were split into five groups for eight weeks: endurance running, rotarod training, each combination in either order, or no training. Endurance work gave the highest hippocampal BDNF, yet the group that did rotarod first and endurance second learned the water maze fastest. Probe trials, object recognition and passive avoidance showed no group differences. The neat lesson: a molecular marker and a behavioural score won't always rise together.
Read the original at Bioengineer.orgNewborn anaesthesia: the Y-maze caught what the water maze didn't
Seven-day-old rats had two hours of sevoflurane or propofol. Both raised hippocampal caspase-3 and left a lasting working-memory dip in the Y-maze at day 42, yet the Morris water maze showed no difference. Metabolomics found drug-specific fingerprints: six metabolites stayed high after propofol, and one phosphatidylcholine stayed low after sevoflurane. A useful case for running more than one test.
Read the original at Scientific Reports