Limits...
Enhancement of encoding and retrieval functions through theta phase-specific manipulation of hippocampus.

Siegle JH, Wilson MA - Elife (2014)

Bottom Line: Assessing the behavioral relevance of the hippocampal theta rhythm has proven difficult, due to a shortage of experiments that selectively manipulate phase-specific information processing.Using closed-loop stimulation, we triggered inhibition of dorsal CA1 at specific phases of the endogenous theta rhythm in freely behaving mice.Conversely, stimulation in the retrieval segment enhanced performance when inhibition was triggered by the trough of theta.

View Article: PubMed Central - PubMed

Affiliation: Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, United States Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, United States jsiegle@mit.edu.

No MeSH data available.


Related in: MedlinePlus

Overview of the behavioral task.(A) Scale drawing of the end-to-end T-maze used in allexperiments. On each trial, mice navigate through the ‘retrievalsegment’ in the direction of the solid arrow and must choose betweenone of two reward sites. Reward is delivered for trajectories that involvetwo turns in the same direction (e.g., the ‘left/left’trajectory shown). Once the reward site is reached, mice must travel back toone of two start locations in order to initiate the next trial. A movablebarrier determines the start location for that trial, and hence which rewardsite will contain the food pellet. The barrier is repositioned randomlyafter each visit to a reward site (whether correct or incorrect). A secondbarrier (not shown) prevents mice from navigating between reward sites aftera decision has been made. The maze is surrounded by 10 cm walls made ofclear acrylic, through which distal cues are visible. (B)Fraction of correct trials in each session leading up to the start ofoptogenetic stimulation for N = 4 individual mice(open shapes) and the mean ± SEM. across all subjects (5-day runningaverage). In the 5 days before the start of optogenetic stimulation (shadedregion), all mice perform significantly above chance (p<0.05, based onp.d.f. of the binomial distribution with probability of 0.5).(C) Trials per minute for the same sessions as inC. Mean for last 5 days (shaded region) is 36.1 ± 18.3trials per session per mouse.DOI:http://dx.doi.org/10.7554/eLife.03061.003
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4384761&req=5

fig1: Overview of the behavioral task.(A) Scale drawing of the end-to-end T-maze used in allexperiments. On each trial, mice navigate through the ‘retrievalsegment’ in the direction of the solid arrow and must choose betweenone of two reward sites. Reward is delivered for trajectories that involvetwo turns in the same direction (e.g., the ‘left/left’trajectory shown). Once the reward site is reached, mice must travel back toone of two start locations in order to initiate the next trial. A movablebarrier determines the start location for that trial, and hence which rewardsite will contain the food pellet. The barrier is repositioned randomlyafter each visit to a reward site (whether correct or incorrect). A secondbarrier (not shown) prevents mice from navigating between reward sites aftera decision has been made. The maze is surrounded by 10 cm walls made ofclear acrylic, through which distal cues are visible. (B)Fraction of correct trials in each session leading up to the start ofoptogenetic stimulation for N = 4 individual mice(open shapes) and the mean ± SEM. across all subjects (5-day runningaverage). In the 5 days before the start of optogenetic stimulation (shadedregion), all mice perform significantly above chance (p<0.05, based onp.d.f. of the binomial distribution with probability of 0.5).(C) Trials per minute for the same sessions as inC. Mean for last 5 days (shaded region) is 36.1 ± 18.3trials per session per mouse.DOI:http://dx.doi.org/10.7554/eLife.03061.003

Mentions: We trained mice on a navigation task that required encoding and retrieval of rewardlocation on individual trials. Mice were placed on an H-shaped track, which consistedof two choice points separated by a central arm (Jones and Wilson, 2005) (Figure1A). At one junction, a movable barrier forced mice to make a left or rightturn in order to arrive at the start location. At the other junction, mice were freeto turn in either direction. A food reward was delivered only if mice chose the armclosest to the most recent start location.10.7554/eLife.03061.003Figure 1.Overview of the behavioral task.


Enhancement of encoding and retrieval functions through theta phase-specific manipulation of hippocampus.

Siegle JH, Wilson MA - Elife (2014)

Overview of the behavioral task.(A) Scale drawing of the end-to-end T-maze used in allexperiments. On each trial, mice navigate through the ‘retrievalsegment’ in the direction of the solid arrow and must choose betweenone of two reward sites. Reward is delivered for trajectories that involvetwo turns in the same direction (e.g., the ‘left/left’trajectory shown). Once the reward site is reached, mice must travel back toone of two start locations in order to initiate the next trial. A movablebarrier determines the start location for that trial, and hence which rewardsite will contain the food pellet. The barrier is repositioned randomlyafter each visit to a reward site (whether correct or incorrect). A secondbarrier (not shown) prevents mice from navigating between reward sites aftera decision has been made. The maze is surrounded by 10 cm walls made ofclear acrylic, through which distal cues are visible. (B)Fraction of correct trials in each session leading up to the start ofoptogenetic stimulation for N = 4 individual mice(open shapes) and the mean ± SEM. across all subjects (5-day runningaverage). In the 5 days before the start of optogenetic stimulation (shadedregion), all mice perform significantly above chance (p<0.05, based onp.d.f. of the binomial distribution with probability of 0.5).(C) Trials per minute for the same sessions as inC. Mean for last 5 days (shaded region) is 36.1 ± 18.3trials per session per mouse.DOI:http://dx.doi.org/10.7554/eLife.03061.003
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4384761&req=5

fig1: Overview of the behavioral task.(A) Scale drawing of the end-to-end T-maze used in allexperiments. On each trial, mice navigate through the ‘retrievalsegment’ in the direction of the solid arrow and must choose betweenone of two reward sites. Reward is delivered for trajectories that involvetwo turns in the same direction (e.g., the ‘left/left’trajectory shown). Once the reward site is reached, mice must travel back toone of two start locations in order to initiate the next trial. A movablebarrier determines the start location for that trial, and hence which rewardsite will contain the food pellet. The barrier is repositioned randomlyafter each visit to a reward site (whether correct or incorrect). A secondbarrier (not shown) prevents mice from navigating between reward sites aftera decision has been made. The maze is surrounded by 10 cm walls made ofclear acrylic, through which distal cues are visible. (B)Fraction of correct trials in each session leading up to the start ofoptogenetic stimulation for N = 4 individual mice(open shapes) and the mean ± SEM. across all subjects (5-day runningaverage). In the 5 days before the start of optogenetic stimulation (shadedregion), all mice perform significantly above chance (p<0.05, based onp.d.f. of the binomial distribution with probability of 0.5).(C) Trials per minute for the same sessions as inC. Mean for last 5 days (shaded region) is 36.1 ± 18.3trials per session per mouse.DOI:http://dx.doi.org/10.7554/eLife.03061.003
Mentions: We trained mice on a navigation task that required encoding and retrieval of rewardlocation on individual trials. Mice were placed on an H-shaped track, which consistedof two choice points separated by a central arm (Jones and Wilson, 2005) (Figure1A). At one junction, a movable barrier forced mice to make a left or rightturn in order to arrive at the start location. At the other junction, mice were freeto turn in either direction. A food reward was delivered only if mice chose the armclosest to the most recent start location.10.7554/eLife.03061.003Figure 1.Overview of the behavioral task.

Bottom Line: Assessing the behavioral relevance of the hippocampal theta rhythm has proven difficult, due to a shortage of experiments that selectively manipulate phase-specific information processing.Using closed-loop stimulation, we triggered inhibition of dorsal CA1 at specific phases of the endogenous theta rhythm in freely behaving mice.Conversely, stimulation in the retrieval segment enhanced performance when inhibition was triggered by the trough of theta.

View Article: PubMed Central - PubMed

Affiliation: Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, United States Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, United States jsiegle@mit.edu.

No MeSH data available.


Related in: MedlinePlus