Name: reversible cooling-induced deactivations to study cortical contributions to obstacle memory in the walking cat
Uploaded: 2017-12-11T12:30:00
Description: Watch this Scientific Journal Video about Reversible Cooling-induced Deactivations to Study Cortical Contributions to Obstacle Memory in the Walking Cat at JoVE.com

We gratefully acknowledge the support of the Canadian Institutes of Health Research, Natural Science and Engineering Research Council of Canada (NSERC), and the Canada Foundation for Innovation. C.W. was supported by an Alexander Graham Bell Canada Graduate Scholarship (NSERC).

All procedures were conducted in compliance with the National Research Council&#39;s Guide for the Care and Use of Laboratory Animals (eighth edition; 2011) and the Canadian Council on Animal Care&#39;s Guide to the Care and Use of Experimental Animals (1993), and were approved by the University of Western Ontario Animal Use Subcommittee of the University Council on Animal Care.
The following procedure can be applied to experiments studying cortical contributions to locomotor control in the wa...

<ol>
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G., Malhotra, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Double+dissociation+of+'what'+and+'where'+processing+in+auditory+cortex.">Double dissociation of 'what' and 'where' processing in auditory cortex.</a> Nat. Neurosci. 11, 609-616 (2008).</li><li>Lomber, S. G., Meredith, M. A., Kral, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cross-modal+plasticity+in+specific+auditory+cortices+underlies+visual+compensations+in+the+deaf.">Cross-modal plasticity in specific auditory cortices underlies visual compensations in the deaf.</a> Nat. Neurosci. 13, 1421-1427 (2010).</li><li>Kok, M. A., Stolzberg, D., Brown, T. A., Lomber, S. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dissociable+influences+of+primary+auditory+cortex+and+the+posterior+auditory+field+on+neuronal+responses+in+the+dorsal+zone+of+auditory+cortex.">Dissociable influences of primary auditory cortex and the posterior auditory field on neuronal responses in the dorsal zone of auditory cortex.</a> J. Neurophysiol. 113, 475-486 (2015).</li><li>Carrasco, A., Kok, M. A., Lomber, S. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+core+auditory+cortex+deactivation+on+neuronal+response+to+simple+and+complex+acoustic+signals+in+the+contralateral+anterior+auditory+field.">Effects of core auditory cortex deactivation on neuronal response to simple and complex acoustic signals in the contralateral anterior auditory field.</a> Cereb. Cortex. 25, 84-96 (2015).</li><li>Coomber, B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cortical+inactivation+by+cooling+in+small+animals.">Cortical inactivation by cooling in small animals.</a> Front. Syst. Neurosci. 5, 53 (2011).</li><li>Malmierca, M. S., Anderson, L. A., Antunes, F. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+cortical+modulation+of+stimulus-specific+adaptation+in+the+auditory+midbrain+and+thalamus:+a+potential+neuronal+correlate+for+predictive+coding.">The cortical modulation of stimulus-specific adaptation in the auditory midbrain and thalamus: a potential neuronal correlate for predictive coding.</a> Front. Syst. Neurosci. 9, 19 (2015).</li><li>Antunes, F. M., Malmierca, M. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+auditory+cortex+deactivation+on+stimulus-specific+adaptation+in+the+medial+geniculate+body.">Effect of auditory cortex deactivation on stimulus-specific adaptation in the medial geniculate body.</a> J. Neurosci. 31, 17306-17316 (2011).</li><li>Peel, T. R., Johnston, K., Lomber, S. G., Corneil, B. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bilateral+saccadic+deficits+following+large+and+reversible+inactivation+of+unilateral+frontal+eye+field.">Bilateral saccadic deficits following large and reversible inactivation of unilateral frontal eye field.</a> J. Neurophysiol. 111, 415-433 (2014).</li><li>Wong, C., Wong, G., Pearson, K. G., Lomber, S. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Memory-guided+stumbling+correction+in+the+hindlimb+of+quadrupeds+relies+on+parietal+area+5.">Memory-guided stumbling correction in the hindlimb of quadrupeds relies on parietal area 5.</a> Cereb. Cortex. , (2016).</li><li>Horsley, V., Clarke, R. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+structure+and+function+of+the+cerebellum+examined+by+a+new+method.">The structure and function of the cerebellum examined by a new method.</a> Brain Behav Evol. 31, 45-124 (1908).</li><li>Lomber, S. G., Malhotra, S., Hall, A. 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The described paradigm employs cooling-induced deactivations of discrete cortical areas using the cryoloop in order to study memory-guided obstacle locomotion in the cat. The visual and tactile obstacle memory paradigms are fairly simple for animals to execute as they exploit naturalistic locomotor behaviors that occur with minimal effort when an animal is motivated to follow a moving food source. Thus, the majority of the training period is devoted to acclimating the animal the testing room and cooling equipment. Most a...

On naturalistic, uneven terrain, sensory information about an obstacle, which can be acquired via vision or touch, can rapidly modify locomotion for avoidance. This careful coordination of stepping movements involves multiple cortical regions1,2. For example, areas of motor cortex3,4 and parietal cortex5,6,7 have been implicated during complex locomotor tasks such as obstacle avoidance. In quadrupedal animals, step modulations required for obstacle avoidance must extend to both the forelegs and hindlegs. If forward locomotion is delayed between the foreleg and hindleg obstacle clearance (which may arise as an animal treads carefully through a complex, naturalistic environment stalking prey), information about the obstacle maintained in the memory is used to guide the hindleg stepping over the obstacle once walking resumes.
Experimental techniques aimed to deactivate discrete cortical areas can be used to study cortical contributions to memory-guided obstacle locomotion. Cooling-induced cortical deactivation provides a reversible, reliable, and reproducible method for assessing cortical contributions to an overt behavior8. Cryoloops made from stainless steel tubing are shaped specific to the cortical area of interest, ensuring highly selective and discrete deactivation of loci. Once implanted, chilled methanol pumped through the lumen of a cryoloop cools the region of cortex directly beneath the loop to &#60;20 &#176;C. Below this critical temperature, synaptic transmission is inhibited in the region of the cortex directly beneath the loop. Such deactivation can be reversed simply by ceasing the flow of methanol. This method has been used to study cortical contributions to sensory processing and behaviors9,10,11,12,13,14,15,16,17, as well as the motor control of saccadic eye movements18 and memory-guided obstacle locomotion19.
The purpose of this protocol is to use reversible cooling-induced deactivations to assess the involvement of the parietal cortical areas for locomotor coordination in the cat. Specifically, memory-guided obstacle locomotion was examined with or without active parietal cortex. These methods have been used to successfully demonstrate the role of parietal area 5 in memory-guided obstacle avoidance in the walking cat19.

<table>
	<tbody>
		<tr>
			<td>Camera</td>
			<td>IDS Imaging Development Systems GmbH</td>
			<td>Model: UI-5240CP-C-HQ</td>
			<td></td>
		</tr>
		<tr>
			<td>Intake tubing</td>
			<td>Restek</td>
			<td>25306</td>
			<td>Unflanged end is submerged in the methanol reservoir while the flanged end is connected to the pump</td>
		</tr>
		<tr>
			<td>Pump</td>
			<td>Fluid Metering, Inc.</td>
			<td>Model: QG 150</td>
			<td></td>
		</tr>
		<tr>
			<td>Nalgene Dewar vacuum flask</td>
			<td>Sigma-Aldrich</td>
			<td>F9401</td>
			<td></td>
		</tr>
		<tr>
			<td>Teflon tubing</td>
			<td>Ezkem</td>
			<td>A051754</td>
			<td></td>
		</tr>
		<tr>
			<td>Microprobe thermometer</td>
			<td>Physitemp</td>
			<td>Model: BAT-12</td>
			<td></td>
		</tr>
		<tr>
			<td>Flanged tube end fittings</td>
			<td>Valco Instruments Co. Inc.</td>
			<td>CF-1BK</td>
			<td>Assorted colours available for colour coding. Packages include the same number of washers as fittings</td>
		</tr>
		<tr>
			<td>Washers</td>
			<td>Valco Instruments Co. Inc.</td>
			<td>CF-W1</td>
			<td>Extra washers</td>
		</tr>
		<tr>
			<td>Flanging kit</td>
			<td>Pro Liquid GmbH</td>
			<td>201553</td>
			<td></td>
		</tr>
		<tr>
			<td>Tubing connector</td>
			<td>Restek</td>
			<td>25323</td>
			<td></td>
		</tr>
		<tr>
			<td>Tubing cutter</td>
			<td>Restek</td>
			<td>25069</td>
			<td></td>
		</tr>
		<tr>
			<td>Male thermocouple connector</td>
			<td>Omega</td>
			<td>SMPW-T-M</td>
			<td>Used to make cable connection to thermometer</td>
		</tr>
		<tr>
			<td>Thermocouple wire</td>
			<td>Omega</td>
			<td>PP-T-24S</td>
			<td>Used to make cable connection to thermometer</td>
		</tr>
		<tr>
			<td>MATLAB</td>
			<td>MathWorks</td>
			<td>n/a</td>
			<td></td>
		</tr>
	</tbody>
</table>

reversible cooling-induced deactivations to study cortical contributions to obstacle memory in the walking cat

On complex, naturalistic terrain, sensory information about an environmental obstacle can be used to rapidly adjust locomotor movements for avoidance. For example, in the cat, visual information about an impending obstacle can modulate stepping for avoidance. Locomotor adaptation can also occur independent of vision, as sudden tactile inputs to the leg by an expected obstacle can modify the stepping of all four legs for avoidance. Such complex locomotor coordination involves supraspinal structures, such as the parietal cortex. This protocol describes the use of reversible, cooling-induced cortical deactivation to assess parietal cortex contributions to memory-guided obstacle locomotion in the cat. Small cooling loops, known as cryoloops, are specially shaped to deactivate discrete regions of interest to assess their contributions to an overt behavior. Such methods have been used to elucidate the role of parietal area 5 in memory-guided obstacle avoidance in the cat.

This protocol has been successfully used to examine parietal cortex contributions to obstacle memory in the walking cat19. In this study, cryoloops were implanted bilaterally over parietal areas 5 and 7 in three adult (&#62;6 months of age) female cats (Figure 5A). Animals were assessed in the tactile obstacle memory paradigm in the absence of cooling (warm, control condition), or when area 5 or 7 was bilaterally deactivated.
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Watch this Scientific Journal Video about Reversible Cooling-induced Deactivations to Study Cortical Contributions to Obstacle Memory in the Walking Cat at JoVE.com

Reversible Cooling-induced Deactivations to Study Cortical Contributions to Obstacle Memory in the Walking Cat

Complex locomotion in naturalistic environments requiring careful coordination of the limbs involves regions of the parietal cortex. The following protocol describes the use of reversible cooling-induced deactivation to demonstrate the role of parietal area 5 in memory-guided obstacle avoidance in the walking cat.

On complex, naturalistic terrain, sensory information about an environmental obstacle can be used to rapidly adjust locomotor movements for avoidance. For ...

The overall goal of the use of cooling-induced deactivations in this study is to assess cortical contributions to obstacle memory in the walking cat. This method can help answer key questions in the field of locomotor control, such as whether the parietal cortex is involved in memory-guided obstacle avoidance. The main advantage of this technique is the ability to reverse the deactivation.This allows each animal to serve as its own control. To begin, construct the apparatus shown here as described in the accompanying text protocol. Next, place the animal onto the testing apparatus while wearing the testing harness, to acclimate the animal to the setup.This leash orientation allows the animal to walk along the central portion of the apparatus without any tension, thus encouraging the animal to remain within this portion of the apparatus. Establishing such boundaries is helpful when working with a moving test subject. Place soft food onto the food platform and then set the animal onto the walkway, allowing it to eat from the platform.Ensure that the animal is comfortable with handling, including instances where the animal must be moved to the start area of the walkway. In order to assess visual obstacle memory, raise the obstacle onto the walkway and place the platform on the far side of the obstacle. Then set the animal at the start area of the walkway and allow the animal to approach the food, stepping over the obstacle with only its forelegs in order to eat from the platform.As the animal continues to eat, lower the obstacle such that it becomes flush with the walkway to prevent any further visual or tactile inputs. Following a variable delay period, move the food forwards again to encourage the animal to resume walking. Also perform trials where the obstacle is absent in order to prevent habituation to the obstacle and development of a learned avoidance response.Observe hind-leg stepping in obstacle-present and obstacle-absent trials to verify typical locomotor behaviors and intact visual obstacle memory prior to cooling. Ensure that the animal can clear the obstacle without contact and that stepping of all four legs is significantly elevated in obstacle-present trials in comparison to obstacle-absent trials. To assess tactile obstacle memory, begin by ensuring that the obstacle is not raised onto the walkway.Then place the animal at the start of the walkway and allow it to walk towards the food platform placed on the far side of the obstacle slot. As the animal eats, raise the obstacle onto the walkway beneath the food dish, preventing any visual input of the obstacle. Then move the food forward.As the food is moved forwards, the animal should contact the obstacle with their forelegs before stepping over it. Allow the animal to continue eating while straddling the obstacle between their fore and hind legs. During this time, lower the obstacle so that it becomes flush with the walkway to prevent any further visual or tactile inputs.Following a variable delay period, move the food forwards once again to encourage the animal to resume walking. In tactile obstacle-absent trials, have the animal approach and eat from the food platform. However, raise and lower the obstacle before moving the food forward with a variable delay.Perform trials where the obstacle is absent and no foreleg contact occurs, to prevent habituation to the presence of the obstacle or the development of a learned avoidance response. Observe the hind-leg stepping in the obstacle-present and obstacle-absent trials to verify normal locomotor behaviors and intact obstacle memory prior to beginning cortical cooling. To deactivate discrete regions of the brain and to assess their contributions to memory-guided obstacle avoidance, implant CryoLoops bilaterally over areas five and seven according to previously reported surgical procedures as described in the accompanying text protocol.Prior to testing, prepare the cooling circuit by combining 200 milliliters of methanol with 500 cc of dry ice to form an ice bath. Connect the intake tube from the methanol reservoir to the pump. Connect the outflow tube that runs to the ice bath to the other side of the pump.Connect the tubing ends to a dummy CryoLoop and ensure that the ends fit snugly over the inlet and outlet tubes to complete the cooling circuit. Next attach the thermocouple plug to a digital thermometer for continuous temperature monitoring. Ensure that the length of this cable and the tubing are sufficient to reach the head of the animal when connected.Then turn on the piston pump using the switch and verify that all connections are snug and no leaks are present. Ensure that the pump setting, length of tubing inside the ice bath, and length of tubing from the ice bath to the dummy loops are optimal such that the dummy CryoLoop temperature can reach a steady state below 5 degrees Celsius. Once satisfied with the initial setup, switch the pump off and remove the dummy CryoLoop.Place the animal on the testing apparatus and buckle the harness. Then secure the strap and attach the leash. Next, remove the protective cap of the implanted CryoLoop to expose the inlet and outlet tubes.Fit tubing ends snugly over the inlet and outlet tubes of the CryoLoop, and connect the thermocouple plug to the digital thermometer. Begin the testing session with a visual or tactile obstacle memory trial. After the initial test, follow with additional trials of all four types in a random fashion.Next, switch on the piston pump and wait one to two minutes for the CryoLoop to reach a temperature of three degrees Celsius. Then run a cool block of trials. During the trials, ensure that the temperature of the CryoLoop is maintained around three degrees Celsius.Then switch off the piston pump and wait for the CryoLoop to return to its original temperature. Run a final rewarm block of trials after the piston pump has been switched off. When the behavioral testing is concluded, remove the tubing from inlet and outlet tubes and ensure that the protective caps are replaced.Be conscious of residual methanol that may drip from the tubing ends and may irritate the animal. Remove the leash and harness and then return the animal to the colony. Finally, use a tube cutter to trim the tube ends to prevent leaky connections on the next testing day.When area five of the cat's brain is bilaterally cooled, hind-leg stepping was significantly attenuated in the obstacle-present trials for both the leading and trailing hind legs. The peak step height of the forelegs in the obstacle-present trials and all of the legs in the obstacle-absent trials were not affected by area five deactivation. Similarly, the peak step height for any leg in either obstacle-present or obstacle-absent trials did not differ from the warm condition when area seven was deactivated.In comparison to both warm and area seven cooled conditions, step clearance was reduced in the leading hind-leg step and in the trailing hind-leg step for the area five cooled condition. Additionally, the step trajectory of the trailing hind leg was affected by area five deactivation as the peak occurred before the obstacle, unlike the stepping in both warm and area seven cooled conditions. While attempting this procedure, it's important to remember to monitor the temperature of cooling loops throughout the experiment to ensure proper deactivation.After watching this video you should have a good understanding of how to reversibly deactivate regions of cortex with cooling in a behaving animal.

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Behavior

Stereotaxic Microinjection of Viral Vectors Expressing Cre Recombinase to Study the Role of Target Genes in Cocaine Conditioned Place Preference

Microinjecting recombinant adenoassociated viral (rAAV) vectors expressing Cre recombinase into distinct mouse brain regions to selectively knockout genes of interest allows for enhanced temporally- and regionally-specific control of gene deletion, compared to existing methods. While conditional deletion can also be achieved by mating mice that express Cre recombinase under the control of specific gene promoters with mice carrying a floxed gene, stereotaxic microinjection allows for targeting of discrete brain areas at experimenter-determined time points of interest. In the context of cocaine conditioned place preference, and other cocaine behavioral paradigms such as self-administration or psychomotor sensitization that can involve withdrawal, extinction and/or reinstatement phases, this technique is particularly useful in exploring the unique contribution of target genes to these distinct phases of behavioral models of cocaine-induced plasticity. Specifically, this technique allows for selective ablation of target genes during discrete phases of a behavior to test their contribution to the behavior across time. Ultimately, this understanding allows for more targeted therapeutics that are best able to address the most potent risk factors that present themselves during each phase of addictive behavior.

This article describes how to microinject viral vectors into mouse brain and then test in a conditioned place preference paradigm that includes an acquisition, extinction and reinstatement phase.

Microinjecting recombinant adenoassociated viral (rAAV) vectors expressing Cre recombinase into distinct mouse brain regions to selectively knockout genes ...

A Procedure to Study the Effect of Prolonged Food Restriction on Heroin Seeking in Abstinent Rats

In human drug addicts, exposure to drug-associated cues or environments that were previously associated with drug taking can trigger relapse during abstinence. Moreover, various environmental challenges can exacerbate this effect, as well as increase ongoing drug intake.
The procedure we describe here highlights the impact of a common environmental challenge, food restriction, on drug craving that is expressed as an augmentation of drug seeking in abstinent rats.
Rats are implanted with chronic intravenous i.v. catheters, and then trained to press a lever for i.v. heroin over a period of 10-12 days. Following the heroin self-administration phase the rats are removed from the operant conditioning chambers and housed in the animal care facility for a period of at least 14 days. While one group is maintained under unrestricted access to food (sated group), a second group (FDR group) is exposed to a mild food restriction regimen that results in their body weights maintained at 90% of their nonrestricted body weight. On day 14 of food restriction the rats are transferred back to the drug-training environment, and a drug-seeking test is run under extinction conditions (i.e.&#160;lever presses do not result in heroin delivery).
The procedure presented here results in a highly robust augmentation of heroin seeking on test day in the food restricted rats. In addition, compared to the acute food deprivation manipulations we have used before, the current procedure is a more clinically relevant model for the impact of caloric restriction on drug seeking. Moreover, it might be closer to the human condition as the rats are not required to go through an extinction-training phase before the drug-seeking test, which is an integral component of the popular reinstatement procedure.

A procedure that allows a demonstration of robust augmentation of drug seeking in food-restricted rats is described. Following heroin self-administration training, rats go through an abstinence period, in a drug-free environment, during which they are mildly food restricted. Drug seeking is then tested in the drug-associated environment.

In human drug addicts, exposure to drug-associated cues or environments that were previously associated with drug taking can trigger relapse during ...

Uncovering Beat Deafness: Detecting Rhythm Disorders with Synchronized Finger Tapping and Perceptual Timing Tasks

A set of behavioral tasks for assessing perceptual and sensorimotor timing abilities in the general population (i.e., non-musicians) is presented here with the goal of uncovering rhythm disorders, such as beat deafness. Beat deafness is characterized by poor performance in perceiving durations in auditory rhythmic patterns or poor synchronization of movement with auditory rhythms (e.g., with musical beats). These tasks include the synchronization of finger tapping to the beat of simple and complex auditory stimuli and the detection of rhythmic irregularities (anisochrony detection task) embedded in the same stimuli. These tests, which are easy to administer, include an assessment of both perceptual and sensorimotor timing abilities under different conditions (e.g., beat rates and types of auditory material) and are based on the same auditory stimuli, ranging from a simple metronome to a complex musical excerpt. The analysis of synchronized tapping data is performed with circular statistics, which provide reliable measures of synchronization accuracy (e.g., the difference between the timing of the taps and the timing of the pacing stimuli) and consistency. Circular statistics on tapping data are particularly well-suited for detecting individual differences in the general population. Synchronized tapping and anisochrony detection are sensitive measures for identifying profiles of rhythm disorders and have been used with success to uncover cases of poor synchronization with spared perceptual timing. This systematic assessment of perceptual and sensorimotor timing can be extended to populations of patients with brain damage, neurodegenerative diseases (e.g., Parkinson&#8217;s disease), and developmental disorders (e.g., Attention Deficit Hyperactivity Disorder).

Behavioral tasks that allow for the assessment of perceptual and sensorimotor timing abilities in the general population (i.e., non-musicians) are presented. Synchronization of finger tapping to the beat of an auditory stimuli and detecting rhythmic irregularities provides a means of uncovering rhythm disorders.

A set of behavioral tasks for assessing perceptual and sensorimotor timing abilities in the general population (i.e., non-musicians) is presented here ...

Utilizing the Modified T-Maze to Assess Functional Memory Outcomes After Cardiac Arrest

Background: Evaluating mild to moderate cognitive impairment in a global cerebral ischemia (i.e. cardiac arrest) model can be difficult due to poor locomotion after surgery. For example, rats who undergo surgical procedures and are subjected to the Morris water maze may not be able to swim, thus voiding the experiment.
New Method: We established a modified behavioral spontaneous alternation T-maze test. The major advantage of the modified T-maze protocol is its relatively simple design that is powerful enough to assess functional learning/memory after ischemia. Additionally, the data analysis is simple and straightforward. We used the T-maze to determine the rats&#39; learning/memory deficits both in the presence or absence of mild to moderate (6 min) asphyxial cardiac arrest (ACA). Rats have a natural tendency for exploration and will explore the alternate arms in the T-maze, whereas hippocampal-lesioned rats tend to adopt a side-preference resulting in decreased spontaneous alternation ratios, revealing the hippocampal-related functional learning/memory in the presence or absence of ACA.
Results: ACA groups have higher side-preference ratios and lower alternations as compared to control.
Comparison with Existing Method(s): The Morris water and Barnes maze are more prominent for assessing learning/memory function. However, the Morris water maze is more stressful than other mazes. The Barnes maze is widely used to measure reference (long-term) memory, while ACA-induced neurocognitive deficits are more closely related to working (short-term) memory.
Conclusions: We have developed a simple, yet effective strategy to delineate working (short-term) memory via the T-maze in our global cerebral ischemia model (ACA).

This protocol describes the use of a modified T-maze to evaluate functional learning/memory in asphyxia cardiac arrest-induced cerebral ischemia.

Background: Evaluating mild to moderate cognitive impairment in a global cerebral ischemia (i.e. cardiac arrest) model can be difficult due to poor ...

Modified Blood Collection from Tail Veins of Non-anesthetized Mice with a Vacuum Blood Collection System and Eyeglass Magnifier

Blood sample collection is the basis of experimental animal research. It is of importance to obtain adequate blood samples for various research purposes. The tail veins of mice are small, and it is sometimes difficult to obtain the required blood volume by conventional puncture methods. This study investigates the superiority of repeated blood sample collection from tail veins of mice through use of a vacuum blood collection system and eyeglass magnifier (experimental group) compared to conventional blood sampling methods (conventional group), performed by beginners and experts, respectively. With the help of an eyeglass magnifier, a butterfly needle tip is inserted into the tail vein of each mouse in the experimental group. When the vein is penetrated successfully, a blood sample is collected in the vacuum collection tube by insertion of the rubber end of a butterfly needle into the vacuum blood collection tube. The plunger is then used to collect blood without the help of the eyeglass magnifier in the conventional group. Success rates of blood sample collection by the beginners and experts were shown to be 70% vs. 100% (p &#60; 0.01) in the experimental group and 35% vs. 85% (p &#60; 0.01) in the conventional group. For both beginners and experts, puncture times required for obtaining required blood sample were significantly lower in the experimental group compared to the conventional group (2.40 &#177; 0.75 vs. 2.90 &#177; 0.31, p &#60; 0.05; 1.15 &#177; 0.37 vs. 1.55 &#177; 0.76, p &#60; 0.05). In conclusion, the presented blood sampling technique is feasible and easy to practice and enables frequent sampling of adequate blood volumes from non-anesthetized mice.&#160;

This study reports blood sampling from tail vein in mice using a vacuum extraction tube system with eyeglass magnifier. Our method is easy to practice and could be used for repeat blood sampling in mice.

Blood sample collection is the basis of experimental animal research. It is of importance to obtain adequate blood samples for various research purposes. ...

Assessing the Coherence of Parents' Short Narratives Regarding their Child Using the Five-Minute Speech Sample Procedure

Valid and efficient measures for assessing the quality of parent-child relationships are needed to facilitate research and evidence-based practice with parents. This paper focuses on such a method, namely Five-Minute Speech Sample-Coherence (FMSS-Coherence). In this method, a parent is asked to speak for five uninterrupted minutes about her/his child and their relationship. The resulted narrative is coded for coherence, namely the extent to which the parent provides&#160;in the narrative&#160;a clear, consistent, multidimensional and well-supported portrayal of the child. FMSS-Coherence is based on attachment research that shows that the coherence of parents&#8217; narratives is indicative of the quality of the parent-child relationship and child adjustment. It overcomes the limitations of attachment narrative measures which are typically labor intensive. FMSS-Coherence is less nuanced than extant attachment narrative measures. Yet, studies of families from different cultural backgrounds, across different child ages and in the context of typically developing children as well as children with special needs suggest that coherence can be reliably evaluated using the FMSS procedure. Furthermore, parents&#8217; FMSS-Coherence is associated with parenting quality and children&#8217;s socio-emotional adjustment. Thus, it holds promise for researchers and practitioners who seek a relatively time- and cost-effective method for assessing the coherence of parents&#8217; narratives regarding their child.

This paper introduces a method for assessing the coherence of parents' short narratives regarding their child and their relationship using the five-minute speech sample procedure.

Valid and efficient measures for assessing the quality of parent-child relationships are needed to facilitate research and evidence-based practice with ...

Assessment of Memory Function in Pilocarpine-induced Epileptic Mice

Cognitive impairment is one of the most common comorbidities in temporal lobe epilepsy. To recapitulate epilepsy-associated cognitive decline in an animal model of epilepsy, we generated pilocarpine-treated chronic epileptic mice. We present a protocol for three different behavioral tests using these epileptic mice: novel object location (NL), novel object recognition (NO), and pattern separation (PS) tests to evaluate learning and memory for places, objects, and contexts, respectively. We explain how to set the behavioral apparatus and provide experimental procedures for the NL, NO, and PS tests following an open field test that measures the animals&#8217; basal locomotor activities. We also describe the technical advantages of the NL, NO, and PS tests with respect to other behavioral tests for assessing memory function in epileptic mice. Finally, we discuss possible causes and solutions for epileptic mice failing to make 30 s of good contact with the objects during the familiarization sessions, which is a critical step for successful memory tests. Thus, this protocol provides detailed information about how to assess epilepsy-associated memory impairments using mice. The NL, NO, and PS tests are simple, efficient assays that are appropriate for the evaluation of different kinds of memory in epileptic mice.

This article presents experimental procedures for assessing memory impairments in pilocarpine-induced epileptic mice. This protocol can be used to study the pathophysiologic mechanisms of epilepsy-associated cognitive decline, which is one of the most common comorbidities in epilepsy.

Cognitive impairment is one of the most common comorbidities in temporal lobe epilepsy. To recapitulate epilepsy-associated cognitive decline in an animal ...

Using a Virtual Reality Walking Simulator to Investigate Pedestrian Behavior

To cross a road successfully, individuals must coordinate their movements with moving vehicles. This paper describes use of a walking simulator in which people walk on a treadmill to intercept gaps between two moving vehicles in an immersive virtual environment. Virtual reality allows for a safe and ecologically varied investigation of gap crossing behavior. Manipulating the initial starting distance can further the understanding of a participant&#8217;s speed regulation while approaching a gap. The speed profile may be assessed for various gap crossing variables, such as initial distance, vehicle size, and gap size. Each walking simulation results in a position/time series that can inform how velocity is adjusted differently depending on the gap characteristics. This methodology can be used by researchers investigating pedestrian behavior and behavioral dynamics while employing human participants in a safe and realistic setting.

This protocol describes use of a walking simulator that serves as a safe and ecologically valid method to study pedestrian behavior in the presence of moving traffic.

To cross a road successfully, individuals must coordinate their movements with moving vehicles. This paper describes use of a walking simulator in which ...

Simultaneous Monitoring of Wireless Electrophysiology and Memory Behavioral Test as a Tool to Study Hippocampal Neurogenesis

Brainwaves amplitude obtained from electroencephalography (EEG) has been well-recognized as a basis for cognitive capacity, memory, and learning on animals and humans. Adult neurogenesis mechanism is also linked to memory and learning improvement. Traditionally, researchers used to assess learning and memory parameters in rodent models by behavioral tasks. Therefore, the simultaneous monitoring of behavioral changes and EEG is particularly interesting in correlating data between brain activity and task-related behaviors. However, most of the equipment required to perform both studies are either complex, expensive, or uses a wired setup network that hinders the natural animals&#8217; movement. In this study, EEG was recorded with a wireless electrophysiology device along with the execution of a novel object recognition task (NORT). The animal&#8217;s behavior was monitored simultaneously by a video tracking system. Both recordings were analyzed offline by their timestamps which were synched to link EEG signals with the animal&#8217;s actions. Subjects consist of adult Wistar rats after medium-term environmental enrichment treatment. Six skull screw electrodes were fixed in pairs on both hemispheres over frontal, central, and parietal regions and were referenced to an electrode located posterior of the nasal bone. NORT protocol consists of exposing the animal to two identical objects for 10 min. After 2 h and 24 h, one of the objects was replaced with a novel one. Exploration time for each object was monitored by a behavioral tracking software (BTS) and EEG data recording. The analysis of the EEG synced with behavioral data consists of estimations of alpha and beta relative band power and comparisons between novel object recognition versus familiar object exploration, between three experimental stages. In this manuscript, we have discussed electrodes manufacturing process, epidural electrodes implantation surgery, environmental enrichment protocol, NORT protocol, BTS setup, EEG &#8211; BTS coupling for simultaneous monitoring in real-time, and EEG data analysis based on automatic events detection.

The protocol presented here provides information on the simultaneous electroencephalography (EEG) and behavioral assessment in real-time. We have discussed all steps involved in this protocol as an attractive solution for researchers in many fields of neuroscience, particularly in learning and memory areas.

Brainwaves amplitude obtained from electroencephalography (EEG) has been well-recognized as a basis for cognitive capacity, memory, and learning on ...

Lower-Limb Biomechanical Characteristics Associated with Unplanned Gait Termination Under Different Walking Speeds

Gait termination caused by unexpected stimulus is a common occurrence in everyday life. This study presents a protocol to investigate the lower-limb biomechanical changes that occur during unplanned gait termination (UGT) under different walking speeds. Fifteen male participants were asked to perform UGT on a walkway at normal walking speed (NWS) and fast walking speed (FWS), respectively. A motion analysis system and plantar pressure platform were applied to collect lower-limb kinematic and plantar pressure data. Paired-sampled T-test was used to examine the differences in lower-limb kinematics and plantar pressure data between two walking speeds. The results showed larger range of motion in the hip, knee, and ankle joints in the sagittal plane as well as plantar pressure in forefoot and heel regions during UGT at FWS when compared with NWS. With the increase in walking speed, subjects exhibited different lower-limb biomechanical characteristics that show FWS associated with greater potential injury risks.

This study compared the biomechanical characteristics of the lower extremity during unplanned gait termination under different walking speeds. The lower-limb kinematic and kinetic data from fifteen subjects with normal and fast walking speeds were collected using a motion analysis system and plantar pressure platform.

Gait termination caused by unexpected stimulus is a common occurrence in everyday life. This study presents a protocol to investigate the lower-limb ...