2-1 Hoy et al 2016 Flashcards
Which strain of a mouse exhibits robust prey-capture behaviour?
The C57BL/6J strain of mouse exhibits robust prey-capture
behavior
What is essential for accurate long-range approach behaviour?
Vision is essential for accurate long-range approach behavior
____ and _____can each contribute to capture at short
ranges
Vision and audition can each contribute to capture at short
ranges
A visual approach paradigm reveals the … what?
A visual approach paradigm reveals the natural operating
parameters of mouse vision
What were previous studies investigating the circuitry that underlies complex ethologically relevant visual behaviors in the mouse restricted to?
fear responses
visual input is
required for accurate approach, allowing maintenance of bearing to within __ degrees of the target on
average during pursuit
visual input is
required for accurate approach, allowing maintenance of bearing to within 11 degrees of the target on
average during pursuit
what species did they use?
the commonly
used laboratory species of mouse (Mus musculus)
How did they test for prey-capture behaviour?
We first tested for prey-capture behavior in
Mus musculus by presenting live crickets (Acheta domestica)
to cricket-naive C57BL/6J mice in their home-cage in the presence of standard mouse chow.
When first testing for prey-capture behaviour, what did they find in group-housed and then individually housed mice?
Within 24 hr of placing crickets in the home-cage of group-housed mice, all of the crickets were captured and consumed.
When the mice were then housed individually, 96.5% (55/57) of the mice captured and consumed crickets.
This demonstrates that mice have both the inclination
and ability to capture live prey.
How did they quantify prey-capture detection and pursuit behaviour?
To quantify prey-capture detection and pursuit behavior, we
next recorded prey performance in an open-field arena
How did they acclimate mice to the set up?
First, mice were
acclimated to their handler and fed crickets once per day in their home-cage for 3 days.
Then, following 24 hr of food restriction, they were exposed to the arena and to crickets within the arena.
What happened on the first day of hunting?
On the first day of hunting (D1) in the arena, mice approached
crickets but often fled, leading to prolonged capture times or
failure to capture
On the first day of hunting (D1) in the arena, mice approached
crickets but often fled, leading to prolonged capture times or
failure to capture
what was this behaviour consistent with?
This behavior is consistent with
the natural tendencies of mice to suppress eating behaviors
in novel environments [9] and to find lit open fields inherently
aversive
How did avoidance behaviour change with repeated exposure in the arena?
avoidance behavior quickly receded with repeated
exposure in the arena.
After 3 days of capture trials, how many mice captured prey reliably?
96.4%, 53/55
When was capture performance deemed reliable?
Capture performance was deemed reliable if three
sequential trials each ended in capture of the cricket in under
30 s
How was prey-capture performance measured?
time to capture
Prey-capture performance reached an asymptote at __ on day __ of hunting in the arena and was stable on day __
Preycapture performance, as measured by time to capture, reached
asymptote at 13 ± 1.1 s on day 4 (D4) of hunting in the arena
and was stable on day 5 (D5)
Preycapture performance, as measured by time to capture, reached
asymptote at 13 ± 1.1 s on day 4 (D4) of hunting in the arena
and was stable on day 5 (D5)
what does this demonstrate?
Together,
this demonstrates that the commonly used C57BL/6L mouse
strain exhibits robust prey-capture behavior and that only
3 days of exposure to insects plus 3 days of contextual acclimation are required to optimize the behavior for measurement in a
controlled setting.
When did they compare prey-capture light/dark auditory/no auditory?
day 5 after
4 days of acclimation to capturing crickets in the arena
How did they eliminate visual cues
allowing mice to capture prey in darkness
How did they eliminate auditory cues
by implanting ear plugs
We observed striking impairments in prey-capture behavior in
the _____ and _____ conditions relative to
the baseline ____ and ____ conditions
We observed striking impairments in prey-capture behavior in
the dark (dark) and ear-plug-dark (EP dark) conditions relative to
the baseline light (light) and ear-plug-only (EP light) conditions
Mice took over ____ times as long to capture a
cricket in the ____ condition than in the ___ condition
Mice took over three times as long to capture a
cricket in the dark condition than in the light condition
Was capture time higher in the dark or the ear plug and dark condition?
EP + dark
What does EP + dark being the longest prey-capture condition suggest?
This confirms
the effectiveness of the ear plug manipulation, and this difference demonstrates that hearing can contribute to prey-capture
behavior in the absence of vision.
How big was the difference between EP light and light?
loss of hearing alone
in the EP light condition had little effect on capture performance
relative to that in the light condition (Figure 2B; EP light: 15 ± 3 s;
light: 11 ± 2 s, p > 0.05).
Importantly, we observed no significant difference across conditions in the amount of time mice spent in a ______ ____ or in the ____ ______ _____ when the mouse
was not contacting the cricket
stationary state or the average locomotor speed
did all mice consume the cricket following capture? what does this imply?
yes. equal motivation
How did they try to clearly understand how vision contributes to efficient
prey capture?
we quantified the orienting behaviors of the mouse
what is the ‘range’?
distance between the mouse’s head and the cricket
what is the ‘azimuth’?
the angular position of the cricket relative to the bearing of the mouse’s head
Consistent with the capture-time data, we
found that mice spent significantly less time at close range
(
Consistent with the capture-time data, we
found that mice spent significantly less time at close range
(<4 cm) under conditions where vision was impaired
In particular, mice had nearly ____ _____ _____ to the
target when they could neither see nor hear.
In particular, mice had nearly randomly distributed range to the
target when they could neither see nor hear.
In particular, mice had nearly randomly distributed range to the
target when they could neither see nor hear.
what does this suggest?
This suggests a
limited role for olfactory and tactile cues in supporting distal
orienting behaviors during prey capture under our testing conditions.
In the absence of vision, hearing does allow mice to increase the likelihood of being within _____ ____,
compared to the absence of both vision and hearing
In the absence of vision, hearing does allow mice to increase the likelihood of being within contact range (<4 cm),
compared to the absence of both vision and hearing
mice maintained
a precise bearing centered on the target in _____ conditions
mice maintained
a precise bearing centered on the target in lighted conditions
prey azimuths were sharply centered on __degrees when mice
could see
prey azimuths were sharply centered on 0 degrees when mice
could see
when mice could neither see
nor hear, the relative angular position of the prey appeared
______, and this distribution was significantly different from ________________________
when mice could neither see
nor hear, the relative angular position of the prey appeared
random, and this distribution was significantly different from all
of the other conditions tested
The distributions of range and
azimuth were significantly different between ___ and __ _____
conditions, demonstrating that ____________________________________
The distributions of range and
azimuth were significantly different between dark and EP dark
conditions, demonstrating that hearing facilitates prey capture
orienting behaviors when vision is absent.
the range and azimuth data suggest what?
the range and azimuth data suggest that vision
is the primary modality driving efficient prey capture behavior
and that hearing may play a role when vision is absent.
How did they determine the cues available during prey capture?
made audio recordings of crickets in the arena
What did the acoustic analysis of crickets show?
crickets never chirped but did produce audible cues
approximately 5–10 dB above the background when they moved
over the substrate
How did they test whether motion was necessary
for capture in the light ?
by measuring performance with immobile targets (fresh-frozen crickets).
Under lit conditions, mice
contacted immobile targets in times comparable to _____________________________
Under lit conditions, mice
contacted immobile targets in times comparable to when they
first make contact with live crickets
Under lit conditions, mice
contacted immobile targets in times comparable to when they
first make contact with live crickets.
what does this mean?
motion
was not necessary to produce optimal prey-capture behavior
in the light, but auditory cues were available to the mouse
when prey moved.
To verify that darkness specifically disrupts performance via
visual impairment of the mouse, what did they do?
sutured the mouse’s eyelids closed
What were the differences between dark, eye-sutured
light, or eye-sutured dark
We saw no significant difference between three
conditions in which vision was impaired: dark, eye-sutured
light, or eye-sutured dark
We saw no significant difference between three
conditions in which vision was impaired: dark, eye-sutured
light, or eye-sutured dark.
What does this demonstrate?
This demonstrates that the impairment of prey-capture performance in
the dark was not due to factors such as changes to cricket
behavior, and it confirms the effectiveness of our visual
manipulations
By examining range, azimuth,
and mouse speed prior to target contact, we identified ___________________________
By examining range, azimuth,
and mouse speed prior to target contact, we identified behavioral criteria that successfully detected approach epochs.
The
co-occurrence of a consistent decrease in range and an absolute azimuth of less than __degrees, while the mouse was moving at
speeds greater than 5 cm/s, predicted 100% of target interceptions under baseline conditions
The
co-occurrence of a consistent decrease in range and an absolute azimuth of less than 90degrees, while the mouse was moving at
speeds greater than 5 cm/s, predicted 100% of target interceptions under baseline conditions
The
co-occurrence of a consistent decrease in range and an absolute azimuth of less than 90degrees, while the mouse was moving at
speeds greater than __cm/s, predicted 100% of target interceptions under baseline conditions
The
co-occurrence of a consistent decrease in range and an absolute azimuth of less than 90degrees, while the mouse was moving at
speeds greater than 5 cm/s, predicted 100% of target interceptions under baseline conditions
The
co-occurrence of a consistent decrease in range and an absolute azimuth of less than 90degrees, while the mouse was moving at
speeds greater than 5 cm/s, predicted ___% of target interceptions under baseline conditions
The
co-occurrence of a consistent decrease in range and an absolute azimuth of less than 90degrees, while the mouse was moving at
speeds greater than 5 cm/s, predicted 100% of target interceptions under baseline conditions
what was an interception?
where the
mouse successfully reaches the location of the prey
what was a capture?
where the mouse successfully grabs and consumes the
prey
how did they measure average frequency of initiating approaches?
the number of approaches per minute
We found that the average frequency of initiating approaches, measured as the number of approaches per minute,
was significantly greater under both ____ conditions as
compared to both ___conditions
We found that the average frequency of initiating approaches, measured as the number of approaches per minute,
was significantly greater under both sighted conditions as
compared to both dark conditions
the likelihood that an approach would end with target interception was
significantly higher in the ___conditions
the likelihood that an approach would end with target interception was
significantly higher in the light conditions
we saw no significant differences in
these measures of approach between the ___ and __ _____
conditions. What did this suggest?
we saw no significant differences in
these measures of approach between the dark and EP dark
conditions, further suggesting that hearing does not play a significant role in the long-distance approach phase of prey
capture.
Although hearing does not affect the accuracy of individual
approaches, the total capture time increased dramatically
when _______________
Although hearing does not affect the accuracy of individual
approaches, the total capture time increased dramatically
when hearing is removed in the dark.
Although hearing does not affect the accuracy of individual
approaches, the total capture time increased dramatically
when hearing is removed in the dark.
how did they try to understand this?
To understand this, we
analyzed the probability of a successful capture given an interception event, or the p(capture|interception)
what did the probability of a successful capture given an interception event show?
that mice performed equally well in the control
condition or with either visual or auditory deprivation alone.
However, when both visual and auditory cues were removed,
the probability of capture following an interception dropped
3-fold
In the probability of a successful capture given an interception event analysis,
when both visual and auditory cues were removed,
the probability of capture following an interception dropped
___-fold
when both visual and auditory cues were removed,
the probability of capture following an interception dropped
3-fold
when we compared the duration
of each intercept that did not lead to capture, mice stayed in
contact (within 4 cm) significantly longer when _____was
available
when we compared the duration
of each intercept that did not lead to capture, mice stayed in
contact (within 4 cm) significantly longer when hearing was
available
How were the trajectories of approaches determined?
The trajectories of approaches were determined by
calculating the azimuth as a function of range for each sensory condition
At ranges of __-__ cm or
less, prey azimuth decreased significantly
under the lighted conditions
At ranges of 15–20 cm or
less, prey azimuth decreased significantly
under the lighted conditions
in the light, mice maintained
a precise bearing as they closed in on the
target (____degrees ± ___degrees at end of approach;
Figure 3F).
in the light, mice maintained
a precise bearing as they closed in on the
target (11.4degrees ± 1.4degrees at end of approach;
Figure 3F).
The accuracy of targeting in
the dark (41.1degrees ± 1.2degrees; Figure 3F) was
near _____, since the azimuth must be
less than ___degrees to be approaching the
target.
The accuracy of targeting in
the dark (41.1degrees ± 1.2degrees; Figure 3F) was
near chance, since the azimuth must be
less than 90degrees to be approaching the
target.
The demonstration that C57BL/6J mice utilize vision to perform
prey capture opens up the potential to study the visual neural circuitry that underlies this behavior.
How did they facilitate these efforts?
we
developed a simplified approach paradigm that relies on vision
The demonstration that C57BL/6J mice utilize vision to perform
prey capture opens up the potential to study the visual neural circuitry that underlies this behavior.
How did they set up a paradigm?
we placed live crickets behind a clear acrylic barrier
that attenuated non-visual cues
why did they restrict the cricket to a 1-D path
simplified the analysis of approaches
What was lateral error?
quantified the horizontal distance
between mouse head position and cricket position during approaches
When was performance in the modified paradigm assessed?
day 5 of training protocol. Identical to the timeline used in the open-field condition.
why did they choose to do the modified paradigm when they did?
the mice were experienced in prey capture
but naive to the experience of encountering prey behind an
acrylic barrier.
In the light, when mice were on the side of the arena with the cricket, what did they do?
In the light, when mice were on the side of the arena with the
cricket, they nearly always directly approached and investigated the cricket’s location , even
though they could not actually contact or capture the cricket
On average, mice in the light contacted the barrier within a lateral error of
___± 0.2 cm of the target, or approximately the length of a ____
On average, mice contacted the barrier within a lateral error of
1.6 ± 0.2 cm of the target, or approximately the length of a cricket
__% ± 5% of mice in the light made contact at the
barrier with a lateral error of less than __cm from target
93% ± 5% of mice made contact at the
barrier with a lateral error of less than 4 cm from target
what happened when mice were placed in the arena in the dark?
In contrast, when mice were placed in the arena in the dark,
their paths appeared directed to random locations along the
acrylic barrier
how often did mice in the dark contact with the barrier
They contacted
the barrier, on average, 13.5 ± 1.4 cm from the target
in the dark condition…
They contacted
the barrier, on average, 13.5 ± 1.4 cm from the target
This is almost ___the length of _______, suggesting what?
This is almost half the length of the barrier, suggesting that barrier contact locations arose randomly
In the dark condition….
Furthermore, the mice
made a ‘‘successful’’ contact on only ___% ± 6% of approaches,
compared to the ___% predicted by chance based on geometry
Furthermore, the mice
made a ‘‘successful’’ contact on only 14% ± 6% of approaches,
compared to the 20% predicted by chance based on geometry
Dark condition mice failed to modify
_____________________________ as they approached
the barrier
o failed to modify
their approach trajectory relative to the prey as they approached
the barrier
Examining the lateral error during approaches shows that mice began deviating toward the target at a range of
___-____ cm, similar to the range at which
they deviated toward the target in the
______
Examining the lateral error during approaches shows that mice began deviating toward the target at a range of 15–20 cm, similar to the range at which they deviated toward the target in the open arena (
How long are crickets?
2cm in length
Given that the crickets are approximately
2 cm in length, a rough estimate of the angular size at which
vision begins to guide approach at ___–___cm is ___degrees–___degrees.
Given that the crickets are approximately
2 cm in length, a rough estimate of the angular size at which
vision begins to guide approach at 15–20 cm is 6degrees–8degrees.
What did this study demonstrate?
that C57BL/6J mice pursue and capture
live insect prey.
Most previous visual behavioral
paradigms with laboratory mice have either relied on ____ ____ ____ [1, 16–19] or _____, including in _____ ____[20, 21].
Most previous visual behavioral
paradigms with laboratory mice have either relied on non-ethological operant training [1, 16–19] or navigation, including in virtual reality [20, 21].
This study also revealed that auditory cues play a role in
mouse prey-capture behavior at ___ ____ _____, although
they were not sufficient for accurate ____-____ ____ in
our paradigm.
This study also revealed that auditory cues play a role in
mouse prey-capture behavior at short target distances, although
they were not sufficient for accurate long-range approaches in
our paradigm.
This study also revealed that auditory cues play a role in
mouse prey-capture behavior at short target distances, although
they were not sufficient for accurate long-range approaches in
our paradigm.
why may this be?
This may be due to the fact that the auditory
cues generated by spontaneous cricket movement were relatively weak at distances where vision could guide approaches
Our results also suggest that olfactory
and tactile cues are insufficient for ______________________________________
Our results also suggest that olfactory
and tactile cues are insufficient for effective orientation behavior
at a distance
olfaction may still play a role in motivation, and mouse strains with poor visual acuity have demonstrated relatively ______ ____ ____
olfaction may still play a role in motivation, and mouse strains with poor visual acuity have demonstrated relatively enhanced olfactory capabilities
M. musculus
is more often considered to be a nocturnal prey species rather
than a ____
M. musculus
is more often considered to be a nocturnal prey species rather
than a predator
Nevertheless, they do consume invertebrates in the wild [30] and are active at dawn and dusk as
well as night, consistent with our findings that they use vision
for prey capture.
Studies of prey capture in non-mammalian species suggest a
role for the ____ ____ in the behavior we observe here
Studies of prey capture in non-mammalian species suggest a
role for the superior colliculus in the behavior we observe here
Classic work investigating prey capture versus object avoidance in toads demonstrated that distinct visual pathways are
required to produce the two types of visually guided behaviors:
what are they?
the optic tectum (non-mammalian homolog of the superior colliculus) mediates prey capture, and the pre-tectum mediates
avoidance [31–33].
recent work in the zebrafish, a
genetically tractable species, has established a role for specific
retinal ____ ______ ____ in triggering approach, as well as
defined ____ ____ ___ within the optic tectum that provide the size tuning that distinguishes prey versus predator
stimuli
recent work in the zebrafish, a
genetically tractable species, has established a role for specific
retinal ganglion cell types in triggering approach, as well as
defined inhibitory cell types within the optic tectum that provide the size tuning that distinguishes prey versus predator
stimuli
In rodents, a combination of lesion and micro-stimulation
experiments conducted in the ___ ___have shown
striking effects on orienting and alerting behavior
In rodents, a combination of lesion and micro-stimulation
experiments conducted in the superior colliculus have shown
striking effects on orienting and alerting behavior
Moreover, recent
studies of predator avoidance behavior in mice have revealed
that the _____can modulate the processing of visual stimuli
that drive innate behaviors in the superior colliculus
Moreover, recent
studies of predator avoidance behavior in mice have revealed
that the cortex can modulate the processing of visual stimuli
that drive innate behaviors in the superior colliculus
