Spatial Learning Flashcards
1
Q
OLTON & SAMUELSON (1976)
A
- how do animals learn spatial locations/routes in radical maze?
- WM = remembering places w/trial (ie. remember which arms already visited)
- reference memory = remember places between trials (ie. remember which arms contain food)
- rats learn spatial relations between arms/external landmarks rather than following rule/marking visited arms
- Q: which tests/evidence required for conclusion?
2
Q
HIPPOCAMPAL LESIONS IMPAIR SPATIAL LEARNING
A
- control condition in hippocampus lesion studies = non-spatial learning (cued learning)
HUMANS - declarative (facts) memories lost w/hippocampal damage BUT not procedural memories; old memories oft NOT lost
ANIMALS - hippocampus = important for acquisition of new info/spatial learning
3
Q
REINER (2009)
A
- new way of thinking about avian forebrain organisation/beh capabilities
- aka. spatial learning in birds
- hippocampus = involved in spatial orientation/learning in birds
4
Q
NAVIGATION
A
WHERE AM I?
- reference to abstract map/allocentric representation; allows to plan for novel route w/o learning it
HOW DO I GET FROM HERE -> GOAL LOCATION?
- following learned routes, novel routes link to learned info; egocentric/allocentric representations
5
Q
WOLF (2011)
A
- path integration in desert ant
- multimodal sensory info used
- cognitive map = using visual allocentric cues in object-centred reference frame to infer direction/distance
- view-matching = inferring direction/distance from views matched w/memorised views in egocentric frame of reference (ie. retiontopic maps)
- path integration (dead reckoning) = updating location/directional orientation by recording idiothetic cues over long distances (ie. turns/steps/odometry); prone to cummulative error
6
Q
EKSTRON, ARNOLD & IARIA (2014)
A
- pointing tasks
- egocentric pointing task = SOP task (ie. please point to ice-cream shop)
- allocentric pointing = JRD task (ie. imagine you’re standing at bookstore facing fast food restaurant; point to camera store)
- accuracy increased in JRD task
- humans may rely on allocentric knowledge for some tasks
- most ethological situations can be solved w/both; could be continuum how each contributes
7
Q
JRD TASK
A
- judgements of relative direction task
- human spatial cognition assay
- requires language use
- pps recall spatial layout in mind for pointing to landmark relative to others
- BUT independent of pps physical position/heading
8
Q
SOP TASK
A
- scene/orientation-dependent pointing task
- verbal instructions
- pps see scene; asked to point to landmarks relative to pps position/heading
9
Q
RINALDI ET AL. (2020)
A
- flexible use of allocentric/egocentric spatial memories activates dif neural networks in mice
- allocentric navigation isn’t only dependent on hippocampus but also distributed neural circuits (dorsomedial striatum/nucleus accumbens/prelimbic & infralimbic cortex)
- retrieval of allocentric/egocentric info = mediated by distinct neural systems
10
Q
FILIMON (2015)
A
- egocentric/allocentric representations in humans
- widely suggested that humans/mammals have cognitive maps based on allocentric representations in brain
- BUT many brain areas map spatila location of objects in egocentric reference frame (ie. relative to eye/head/hand) in (ie.) parieto-frontal cortex
- Q: could allocentric representations be explained via egocentric spatial reference frames?
11
Q
POTENTIAL ALLOCENTRIC TASK EFFECTS
A
- mental shift of objects to center it frontally (egocentric left-right decisions)
- mental rotation
- could mediate view-dependent object/scene recognition
12
Q
LIMBIC SYSTEM
A
- thalamus
- cingulate gyrus
- fornix
- amygdala
- hippocampus
- parahippocampal gyrus
13
Q
MORRIS ET AL. (1982)
A
- hippocampus lesions prior to training DON’T specifically impair working/reference memory BUT spatial task
- all rats showed same escape latency in 2nd experiment phase (cue-based navigation)
- reversal to hidden platform in 3rd phase = rats w/hippocampal lesions performed poorly again
- lesions after training = less strong effects; hippocampus ISN’T site for permanent memory storage
14
Q
O’KEEFE & DOSTROVSKY (1971)
A
- place cells in hippocampus; encoding of observer-independent spatial location
- populations of neurons (extracellular recordings of freely moving rats) w/dif spatial preferences in hippocampus; collectively said cells form spatial maps
15
Q
MULLER ET AL. (1987)
A
- place field maps; signal place recognition
- dif cells encode dif locations
- shape/size of firing fields vary
- not all complex spike cells act like place cells; preference can change in novel environment
- single cells can code for dif spatial locations in dif contexts firing w/varied patterns; may have dif patterns in same environment (ie. lights on/off)
16
Q
EICHENBAUM ET AL. (1987)
A
- place cells rely on spatial info derived from idiothetic cues
- vestibular activation/visual input from animal’s own movement modulate firing patterns of place cells
- place cells continue firing in dark (ie. when light switched off)
- rats trained to alternate turns; some place cells fired for location as expected BUT others fired location in conjunction w/anticipation of left/right turn to be made
17
Q
CAREW (2005)
A
- head direction cells fire w/directional pref maintained in familiar/novel environments
- head direction cells = location-invariant
18
Q
MOSER & MOSER (2007)
A
- coding representation of space
- grid cells (together w/other cells in entorhinal cortex that recognise direction of animal head/border of room) form networks w/place cells in hippocampus
- said circuitry constitutes comprehensive positioning system (aka. inner GPS) in brain; positioning system in appears to have similar components as those in rats
19
Q
TAUBE (2006)
A
AVH CELLS
- angular head velocity cells
- firing rate increases linearly as function of angular speed (ie. for both CW/CCW head turns in symmetrical AVH cells)
GRID CELL
- neuron that fires at multiple locations in environment; locations of high activity form repeating hexagonal grid-like pattern
HD CELLS
- head direction cells
20
Q
GOLGI’S METHOD
A
- staining neurons; revolutionised study of brains/neurons
HIPPOCAMPAL FORMATION (MEDIAL TEMPORAL LOBE) - dentate gyrus
- hippocampus proper (cornu ammonis)
- subiculum (incl. adjacent areas of parahippocampal gyrus (ie. presubiculum/parasubiculum/entorhinal cortex)
21
Q
LOPEZ-ROJAS & KREUTZ (2016)
A
- dentate gyrus filters incoming excitation from entorhinal cortex
- classical trisynaptic hippocampal circuit model of info processing (Anderson et al. (1971))
- parallel connectivity; entorhinal cortex projects to both CA1/CA3
22
Q
CAREW (2000)
A
- CA1/CA3 = major subdivisions in hippocampus
- CA = cornu ammonis (Ammon’s horn); pyramidal cell layers
- remarkably regular arrangement of soma/projections of principle neurons (pyramidal cells)
- can take slices from hippocampus that preserve functioning network
23
Q
TRISYNAPTIC CIRCUIT
A
- connection from entorhinal cortex -> dentate granule cells via preforant path
- connection from granule cells -> CA3 pyramidal cells via mossy fibers
- connection from CA3 pyramidal cells -> CA1 pyramidal cells via Schaffer collaterals
24
Q
TSIEN ET AL. (1996)
A
- targeting NMDA receptor w/genetic tools
- LTP = normal in wild-type animals/controls (genetically engineered) BUT absent in NMDA knockouts
25
Q
MORRIS ET AL. (1986)
A
- Q: does hippocampal LTP have anything to do w/spatial learning?
- APV = NMDA blocker
- 8 days training w/hidden platform
- day 9 = test w/o platform
- same APV treatment also suppressed LTP
26
Q
SUMMARY (1)
A
- spatial info = important for beh
- animals can find/learn routes & rely on egocentric ref frames
- some animals (birds travelling over long distances/mice)/humans also form allocentric representations
- hippocampus = major important for spatial learning/navigation in vertebrates BUT not exclusive role; other areas also involved
27
Q
SUMMARY (2)
A
- blocking NMDA receptors prevents LTP/spatial learning providing evidence for causal link
- explanations for species/sex-based/individual dif = intuitive to human beh BUT can be influenced by researcher’s confirmation/biases; experimental scrutiny/bias awareness/diversity = key to advance scientific knowledge
