We would like to thank Joy Bergmann, Attilio Ceretti, Sarah Cohen, Nina Duncan, Arron Hall, Hanna Lefebo, and Madeleine Salvatore for their assistance with the behavior, and Dr. Vinay Parikh, Dr. Brittney Yegla, and Rob Cole for their advice on the SAT parameters. We would like to thank Dr. Jill McGaughy for tips on the training procedure. This work was supported by the National Institutes of Health grant NIMH 092438 and National Science Foundation grant IOS 1552416 to D.A.B.

All experiments were conducted in accordance with the National Institutes of Health guidelines and were approved by the Temple University Institutional Animal Use and Care Committee. This protocol was developed with adult (~60 days of age when starting the study) male and female Sprague-Dawley rats (Charles River).
1. Materials for Touchscreen SAT
<ol>
	<li>Ensure that a sound attenuation cubicle surrounds each touchscreen chamber and that chambers are equipped with a house light, tone generator, camera positioned above the chamber, and a pellet dispenser with feeder reward area (that can be illuminated) on the wall opposite the touchscreen.</li>
	<li>Use a feeder reward area with a large aperture if cannula or electrodes implants are planned. Use 45 mg reward pellets that have been sifted with a flour sifter to reduce dust, which can clog the feeder.</li>
	<li>Fit each chamber with a black acrylic mask (3.175 mm thick, matte) to limit response areas on the touchscreen. Prepare the mask with a central circle opening (28.58 mm diameter, 107.95 mm from the bottom, centered between the left and right side) for the light stimulus and two square response areas (28.57 mm x 28.57 mm) each positioned below and off center (one 85.73 mm from the left side and one 85.73 mm from the right side, and both 34.93 mm from the bottom). A depiction of the mask can be found in the publication, Wicks, et al.19.</li>
	<li>Place the mask in front of the touchscreen with matte finish positioned towards the chamber.</li>
</ol>
2. Schedule Design for Touchscreen SAT
NOTE: The below protocol details how to set the parameters for the shaping and testing schedules for touchscreen SAT. All these schedules are also available upon request. Table 1 depicts the schedule parameters.
<ol>
	<li>Nose Poke Shaping parameters.
	<ol>
		<li>Set program so that no signals are presented and the houselight remains off.</li>
		<li>Set the feeder reward area to illuminate to indicate the presence of a pellet and for this light to turn off following pellet retrieval as determined by the feeder port infrared beam.</li>
		<li>Set program so that nose-pokes in either response area are rewarded with food pellets under a fixed-ratio 1 (FR1) reinforcement schedule (i.e., each appropriate response is rewarded). However, set the program so that if the side differential for nose-pokes is five or greater, the rat must poke the non-favored side to receive a reward to prevent the development of a side bias.</li>
		<li>Set the session to end after 40 min or 120 rewarded pokes. Advance subjects to Training Schedule 1 if they complete 120 nose-pokes in 40 min for two consecutive days.</li>
	</ol>
	</li>
	<li>Description of shared parameters for Training Schedule 1, Training Schedule 2, and SAT.
	<ol>
		<li>Program training schedules so that the houselight remains on to increase attentional demands.</li>
		<li>Program each session so that it consists of 162 trials that can be divided into three blocks of 54 trials per block with the intertrial interval (ITI) set at 9 &#177; 3 s.</li>
		<li>Ensure that signal and non-signal trials are pseudorandomized such that the same number of signal and non-signal trials occur in each of the three blocks.</li>
		<li>Set the program to deliver a food pellet and turn on the food port light automatically at the start of each session. When an infrared beam break indicates that the rat has removed its head from the reward area, set the program to turn off the food port light and begin the first ITI.</li>
		<li>Following each trial (i.e., signal or non-signal), set the program to indicate the 4-s response window with a 200 ms, 70 dB tone (3 kHz).</li>
		<li>If the rat correctly responds, set the program to initiate the ITI when the rat removes its head from the reward area. If the rat incorrectly responds, set the ITI to begin following the response. If the rat omits (i.e., makes no response), set the ITI to begin after the termination of the response window.</li>
		<li>For counterbalancing, develop two versions of these schedules, the first with the right response area designated for hits (Version A) and the second with the left response area designated for hits (Version B).</li>
	</ol>
	</li>
	<li>Training Schedule 1 parameters.
	<ol>
		<li>Set all signal durations to 500 ms.</li>
		<li>On signal trials, set the program to simultaneously illuminate the response area designated for hits at 50% intensity, along with the signal, to draw the rat&#39;s attention to the correct response area.</li>
		<li>Keep the designated area for correct rejections unlit on non-signal trials.</li>
		<li>Set the program so that incorrect responses trigger correction trials in which the previous trial type (i.e., signal or non-signal) is presented again. Ensure that a correct response or four consecutive incorrect responses ends the series of correction trials. Do not count correction trials towards the 162 total trials required for task completion.</li>
		<li>Advance subjects to Training Schedule 2 if they have at least 70% hits, at least 70% correct rejections, and less than 20% omissions for three consecutive days.</li>
	</ol>
	</li>
	<li>Training Schedule 2 parameters.
	<ol>
		<li>Set all signal durations to 500 ms.</li>
		<li>Unlike Training Schedule 1, set the program to keep the response area for hits unlit on signal trials.</li>
		<li>Unlike Training Schedule 1, do not have the program execute correction trials.</li>
		<li>Keep all other parameters the same as in Training Schedule 1.</li>
		<li>Advance subjects to SAT if they have at least 70% hits, at least 70% correct rejections, and less than 20% omissions for three consecutive days.</li>
	</ol>
	</li>
	<li>SAT parameters.
	<ol>
		<li>Set three signal durations: 500 ms, 50 ms, and 25 ms.</li>
		<li>Set the program to present the variable signals in a pseudorandom fashion, such that the three signal durations are presented an equal number of times during each one of the three trial blocks.</li>
		<li>Define criteria performance as at least 70% hits at the 500 ms signal duration, at least 70% correct rejections, and less than 20% omissions for three consecutive days.</li>
	</ol>
	</li>
</ol>
<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Training Stage</td>
			<td>Max. Trials</td>
			<td>Signal Duration (ms)</td>
			<td>Special Conditions</td>
			<td>Criteria</td>
			<td>Median Days per Stage</td>
		</tr>
		<tr>
			<td>Nose Poke Shape</td>
			<td>120</td>
			<td>No events</td>
			<td>Houselight on</td>
			<td>120 trials in 40 minutes</td>
			<td>Males: 2, Females: 2</td>
		</tr>
		<tr>
			<td>Training Schedule 1</td>
			<td>162</td>
			<td>500</td>
			<td>Houselight on; Correction trials; Response window lit at 50% during signal trials</td>
			<td>&#62; 70% Hits, &#62; 70% CR, &#60; 20% Omissions for 3 consecutive days</td>
			<td>Males: 19, Females: 25</td>
		</tr>
		<tr>
			<td>Training Schedule 2</td>
			<td>162</td>
			<td>500</td>
			<td>Houselight on</td>
			<td>&#62; 70% Hits, &#62; 70% CR, &#60; 20% Omissions for 3 consecutive days</td>
			<td>Males: 13, Females: 21</td>
		</tr>
		<tr>
			<td>SAT</td>
			<td>162</td>
			<td>500, 50, 25</td>
			<td>Houselight on</td>
			<td>&#62; 70% Hits at 500 ms, &#62; 70% CR, &#60; 20% Omissions for 3 consecutive days</td>
			<td>Males: 18, Females: 12</td>
		</tr>
	</tbody>
</table>
Table 1: Training Schedules and Average Acquisition Time for Each Schedule.
<ol start="6">
	<li>Distractor SAT.
	<ol>
		<li>Keep parameters for Blocks 1 and 3 identical to SAT.</li>
		<li>Program the houselight so that it flashes at a frequency of 0.5 Hz during Block 2.</li>
		<li>When analyzing data, compare performance between Blocks 1, 2, and 3 to analyze performance before, during, and after the distractor within the same session.</li>
	</ol>
	</li>
	<li>Data extraction program.
	<ol>
		<li>Extract the following data for SAT and distractor SAT broken down by trial block and each signal duration (for VI and percent hits):
		<ol>
			<li>Calculate the percentage of hits by dividing the number of hits by the combined number of hits and misses and then multiplying by 100.</li>
			<li>Calculate the percentage of correct rejections by dividing the number of correct rejections by the combined number of correct rejections and false alarms and then multiplying by 100.</li>
			<li>Calculate the vigilance index (VI), an overall measure of attentional performance, using the following formula: <img alt="Equation" src="/files/ftp_upload/56219/56219eq1.jpg" /> where h and f are the proportion of hits on signal trials and false alarms on non-signal trials, respectively. The values of VI range from -1 to +1 with a value of 0 indicating that the rat is unable to distinguish between signal and non-signal trials. Do not include omitted trials in the VI measure.</li>
			<li>Calculate the percentage of omissions by determining the percentage of trials where no response occurred.</li>
		</ol>
		</li>
	</ol>
	</li>
</ol>
3. Procedure for Running Rats in Touchscreen SAT
<ol>
	<li>Reverse light/dark cycle considerations 
	NOTE: We test our rats during their dark cycle, but see the discussion section for considerations regarding testing in the light cycle.
	<ol>
		<li>For testing during the dark cycle, begin behavior testing at least 30 min after the start of the dark cycle.</li>
		<li>Once the equipment is set up, keep the behavioral testing room in darkness during all training and testing procedures to avoid interfering with the rats&#39; sleep/wake cycle.</li>
		<li>Cover rat cages with black towels during transport to minimize light exposure.</li>
		<li>Use headlights with red lights turned on for hands-free work in the dark without disrupting the light/dark cycle.</li>
	</ol>
	</li>
	<li>Food restriction procedures and schedule assignment
	<ol>
		<li>Don appropriate personal protective equipment (PPE; e.g., gloves, mask, bonnet, lab coat, shoe covers, etc.) prior to handling the rats.</li>
		<li>When rats arrive to the colony room, house rats individually or in groups. Most rats in our studies are eventually implanted with cannulae, which necessitates individual housing.</li>
		<li>Handle rats daily for 5 min per day, 5 days prior to the start of the study.</li>
		<li>Prior to food restriction, record each rat&#39;s free feeding weight and calculate their target weight at 85% of their free feeding weight.</li>
		<li>Food restrict rats for 3 days before beginning shaping.</li>
		<li>Prior to shaping, pre-expose rats to 15 food reward pellets in their home cage.</li>
		<li>After the initial food restriction, adjust daily food amounts as needed to maintain performance on the attention task and ~85% of each rat&#39;s free-feeding body weight allowing for slight weight gain over time (see guidelines25). Prior to starting a new schedule, restrict rats more than usual to increase motivation.</li>
		<li>On the day(s) of a week when rats do not perform behavior, increase their food by at least 1.0 g to make-up for the calories that they would have received while being rewarded during the behavioral task.</li>
		<li>Record each rat&#39;s weight after their session is completed.</li>
		<li>Do not feed rats until at least 30 min after completing their session to avoid an association between behavioral testing cessation and feeding time. If rats are group housed, feed each rat separately for 1 h, then put rats back into the group housing condition.</li>
		<li>Prior to the start of the study, randomly assign each rat to one of the two versions of the training schedules (A or B) and maintain them on their designated version throughout the training and SAT procedures.</li>
	</ol>
	</li>
	<li>Daily running procedure
	<ol>
		<li>Don appropriate PPE.</li>
		<li>Power up operant chambers and the computer.</li>
		<li>Check that the pellet dispensers are filled with pellets and that the mask is inserted in front of the touchscreen.</li>
		<li>Ensure that each box is functioning properly by verifying that the feeder is properly dispensing food and the screen, lights, and tone are working. A simple box test schedule can be written for this purpose and ours is available upon request.</li>
		<li>Load the correct schedule in each box, paying close attention to the appropriate version (i.e., A or B). Input relevant information regarding animal ID, sex, experimental condition, user initials, and other notes if needed (e.g., infusion day 1).</li>
		<li>Retrieve rats from colony room and put them in the appropriate box.</li>
		<li>Start the session.</li>
		<li>Watch performance via the video camera set-up at the start of the session for several minutes to ensure that everything is functioning properly. Check performance periodically.</li>
		<li>Once a session is complete, record summary data (e.g., percent hits, percent CRs, percent omissions) and any issues in the notebook.</li>
		<li>Wipe each chamber with 10% ethanol and replace the bedding in between sets of animals.</li>
		<li>After running the final set of rats for the day, clean the chambers thoroughly with 10% ethanol, ensuring that the floor grid is as clean as possible, and replace the bedding.</li>
		<li>Back up data on a cloud server and extract any critical data.</li>
		<li>Power down equipment.</li>
		<li>Run animals at the same time in the same boxes each day.</li>
		<li>Run rats 5 - 6 days a week (we run our rats 6 days a week).</li>
	</ol>
	</li>
</ol>
4. Troubleshooting the Behavior
NOTE: It is normal for performance to drop when rats are transitioned to the next shaping phase (i.e., Nose Poke Shape to Training Schedule 1, Training Schedule 1 to Training Schedule 2, Training Schedule 2 to SAT). However, if performance does not improve over time or if a rat was performing well and then suddenly stops performing well, most often the issue is with food restriction.
<ol>
	<li>Troubleshooting food restriction issues
	<ol>
		<li>If food restriction is a suspected issue, watch the rat perform the task to help diagnose where the problem lies and check the omission numbers, particularly across the session.</li>
		<li>If a rat has high omissions, especially if they increase in Block 3, and sits calmly in the box not performing, reduce daily food amount by 1 g and monitor the situation to determine if performance is improved.</li>
		<li>If a rat has high omissions, impatiently pokes the screen, and runs back and forth to the food port throughout the session, increase daily food amount by 1 g and monitor the situation to determine if performance is improved.</li>
		<li>In cases where it is difficult to tell whether a rat is over- or underfed, increase food amount for 2 days and monitor performance. If performance does not improve or gets worse, decrease food amount for 2 days and monitor performance</li>
		<li>If performance does not improve after adjusting food restriction, move the rat to an easier scheduled as detailed next.</li>
	</ol>
	</li>
	<li>Troubleshooting performance at different schedules of training 
	NOTE: Drop a poorly performing rat if its acquisition time exceeds two standard deviations above the mean number of days that it takes an animal of its same sex to reach criteria on that schedule. We have made suggestions based on our data for cut-offs for Sprague-Dawley rats, but these numbers may need to be adjusted for different strains.
	<ol>
		<li>Training Schedule 1: For Training Schedule 1, drop Sprague-Dawley males if they cannot acquire after 36 days and drop females if they have not acquired after 48 days.</li>
		<li>Training Schedule 2: If a rat&#39;s performance on Training Schedule 2 stagnates below criteria for 12 days in a row and a food restriction issue has been ruled out, move the rat back down to Training Schedule 1 for a minimum of 5 days or until it reaches criteria. If the rat does not reach criteria on training Schedule 1 after 12 days, drop the rat from the study. If the rat passes Training Schedule 1 and is moved back to Training Schedule 2, but does not improve after 36 and 42 days for males and females, respectively, after initially starting Training Schedule 2, then drop the rat from the study.</li>
		<li>SAT: If a rat&#39;s performance on SAT stagnates below criteria for 12 days in a row and a food restriction issue has been ruled out, move the rat back down to Training Schedule 1 for a minimum of 5 days or until they reach criteria. If the rat does not reach criteria on Schedule 1 in 12 days, drop the rat from the study. If the rat passes Training Schedule 1 and is moved back to SAT, but does not improve after 41 and 28 days for males and females, respectively, after initially starting SAT, drop the rat from the study.</li>
	</ol>
	</li>
	<li>Troubleshooting other issues
	<ol>
		<li>If a rat develops a side bias (i.e., consistently scoring &#62;70% hits and &#60;40% on correct rejections, or vice versa) while on Training Schedule 2 or SAT, move the rat to Training Phase 1, which has correction trials that encourage the rat to respond to both response areas. Keep the rat at Training Schedule 1 for a minimum of 5 days or until they reach criteria. Drop the rat from the study if criteria on training Schedule 1 is not met after 12 days.</li>
		<li>Consult with the veterinary staff immediately if a rat stops eating, develops porphyrin, or otherwise is showing signs of pain and distress.</li>
	</ol>
	</li>
</ol>

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C., 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=The+touchscreen+operant+platform+for+assessing+executive+function+in+rats+and+mice.">The touchscreen operant platform for assessing executive function in rats and mice.</a> Nat Protoc. 8 (10), 1985-2005 (2013).</li><li>Gill, T. M., Sarter, M., Givens, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sustained+visual+attention+performance-associated+prefrontal+neuronal+activity:+evidence+for+cholinergic+modulation.">Sustained visual attention performance-associated prefrontal neuronal activity: evidence for cholinergic modulation.</a> J Neurosci. 20 (12), 4745-4757 (2000).</li><li>Mazure, C. M., Jones, D. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Twenty+years+and+still+counting:+including+women+as+participants+and+studying+sex+and+gender+in+biomedical+research.">Twenty years and still counting: including women as participants and studying sex and gender in biomedical research.</a> BMC Womens Health. 15 (1), 94 (2015).</li><li>Toth, L. A., Gardiner, T. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Food+and+Water+Restriction+Protocols:+Physiological+and+Behavioral+Considerations.">Food and Water Restriction Protocols: Physiological and Behavioral Considerations.</a> J Am Assoc Lab Anim Sci. 39 (6), 9-17 (2000).</li><li>Nuechterlein, K. H., Luck, S. J., Lustig, C., Sarter, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=CNTRICS+Final+Task+Selection:+Control+of+Attention.">CNTRICS Final Task Selection: Control of Attention.</a> Schizo Bull. 35 (1), 182-196 (2009).</li><li>Burk, J. A., Herzog, C. D., Porter, M. C., Sarter, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Interactions+between+aging+and+cortical+cholinergic+deafferentation+on+attention.">Interactions between aging and cortical cholinergic deafferentation on attention.</a> Neurobiol Aging. 23 (3), 467-477 (2002).</li><li>St Peters, M., Demeter, E., Lustig, C., Bruno, J. P., Sarter, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Enhanced+control+of+attention+by+stimulating+mesolimbic-corticopetal+cholinergic+circuitry.">Enhanced control of attention by stimulating mesolimbic-corticopetal cholinergic circuitry.</a> J Neurosci. 31 (26), 9760-9771 (2011).</li><li>Turchi, J., Holley, L. A., Sarter, M. <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+nicotinic+acetylcholine+receptor+ligands+on+behavioral+vigilance+in+rats.">Effects of nicotinic acetylcholine receptor ligands on behavioral vigilance in rats.</a> Psychopharmacology. 118 (2), 195-205 (1995).</li><li>Newman, L. A., McGaughy, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Attentional+effects+of+lesions+to+the+anterior+cingulate+cortex:+How+prior+reinforcement+influences+distractibility.">Attentional effects of lesions to the anterior cingulate cortex: How prior reinforcement influences distractibility.</a> Behav neurosci. 125 (3), 360-371 (2011).</li><li>Gritton, H. J., Stasiak, A. M., Sarter, M., Lee, T. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cognitive+Performance+as+a+Zeitgeber:+Cognitive+Oscillators+and+Cholinergic+Modulation+of+the+SCN+Entrain+Circadian+Rhythms.">Cognitive Performance as a Zeitgeber: Cognitive Oscillators and Cholinergic Modulation of the SCN Entrain Circadian Rhythms.</a> PLOS ONE. 8 (2), e56206 (2013).</li><li>Newman, L. A., McGaughy, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cholinergic+deafferentation+of+prefrontal+cortex+increases+sensitivity+to+cross-modal+distractors+during+a+sustained+attention+task.">Cholinergic deafferentation of prefrontal cortex increases sensitivity to cross-modal distractors during a sustained attention task.</a> J Neurosci. 28 (10), 2642-2650 (2008).</li><li>Yu, A., Dayan, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Uncertainty,+Neuromodulation,+and+Attention.">Uncertainty, Neuromodulation, and Attention.</a> Neuron. 46 (4), 681-692 (2005).</li><li>Bari, A., Dalley, J. W., Robbins, T. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+application+of+the+5-choice+serial+reaction+time+task+for+the+assessment+of+visual+attentional+processes+and+impulse+control+in+rats.">The application of the 5-choice serial reaction time task for the assessment of visual attentional processes and impulse control in rats.</a> Nat Protoc. 3 (5), 759-767 (2008).</li><li>Bhandari, J., Daya, R., Mishra, R. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Improvements+and+important+considerations+for+the+5-choice+serial+reaction+time+task-An+effective+measurement+of+visual+attention+in+rats.">Improvements and important considerations for the 5-choice serial reaction time task-An effective measurement of visual attention in rats.</a> J Neurosci Meth. 270, 17-29 (2016).</li><li>Bangasser, D. A., Shors, T. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+hippocampus+is+necessary+for+enhancements+and+impairments+of+learning+following+stress.">The hippocampus is necessary for enhancements and impairments of learning following stress.</a> Nat Neurosci. 10 (11), 1401-1403 (2007).</li><li>Wiersielis, K. R., 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=Sex+differences+in+corticotropin+releasing+factor-evoked+behavior+and+activated+networks.">Sex differences in corticotropin releasing factor-evoked behavior and activated networks.</a> Psychoneuroendocrinology. 73, 204-216 (2016).</li><li>Parikh, V., 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=Diminished+trkA+receptor+signaling+reveals+cholinergic-attentional+vulnerability+of+aging.">Diminished trkA receptor signaling reveals cholinergic-attentional vulnerability of aging.</a> Eur J Neurosci. 37 (2), 278-293 (2013).</li><li>Prusky, G. T., Harker, K. T., Douglas, R. M., Whishaw, I. Q. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Variation+in+visual+acuity+within+pigmented,+and+between+pigmented+and+albino+rat+strains.">Variation in visual acuity within pigmented, and between pigmented and albino rat strains.</a> Behav Brain Res. 136 (2), 339-348 (2002).</li><li>Peters, M., Cherian, A. K., Bradshaw, M., Sarter, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sustained+attention+in+mice:+Expanding+the+translational+utility+of+the+SAT+by+incorporating+the+Michigan+Controlled+Access+Response+Port+(MICARP).">Sustained attention in mice: Expanding the translational utility of the SAT by incorporating the Michigan Controlled Access Response Port (MICARP).</a> Behav Brain Research. 225 (2), 574-583 (2011).</li><li>Romberg, C., Mattson, M. P., Mughal, M. R., Bussey, T. J., Saksida, L. 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The authors have nothing to disclose.

Deficits in sustained attention are reported in neuropsychiatric, neurodevelopmental, and neurodegenerative disorders1,2,3, but the processes that contribute to optimal versus disrupted attention are understudied. This is, in part, because specialized equipment limits the easy adaptation of rodent attention tasks. However, touchscreen chambers are addressing this issue by providing the flexibility to run a variety of cognitive t...

Disorders ranging from attention deficit hyperactivity disorder (ADHD) to schizophrenia to Alzheimer&#39;s disease, share attentional impairments as a feature1,2,3. Deficits in sustained attention&#8212;the ability to monitor continuously a situation for intermittent and unpredictable events&#8212;are particularly disruptive, because sustained attention is crucial for selective and divided attention, as well as other cognitive processes4,5. Even in healthy people, difficulty with sustaining attention negatively affects cognition, impairing daily function6. Thus, understanding the neurobiological basis of sustained attention and how it becomes dysregulated could lead to interventions to improve cognition that would benefit many people.
In order to delineate circuits and molecular processes that contribute to proper versus disrupted attention, many researchers have turned to non-human animal models, where the manipulation of specific cell populations and molecular processes during attention tasks is possible. The effort has led to the development of a variety of operant attention tasks that can assess the ability to sustain attention7,8,9,10. One such paradigm, developed by McGaughy and Sarter (1995), is known as the sustained attention task (SAT). Rodents trained in SAT must distinguish signal trials, in which a signal light briefly flashes, from non-signal trials. Attentional demands can be increased by introducing a visual distractor (flashing houselight)10. The parameters critical for assessing attention in SAT are well documented and this task has been validated in male and female rats and mice10,11,12. A version has even been adapted for humans, highlighting the translational utility of SAT13. Importantly, the use of this task helped implicate the basal forebrain corticopetal system in sustained attention4. Specifically, cholinergic neurons in the nucleus basalis of Meynert (NBM)/ substantia inominata (SI) region of the basal forebrain that project to the prefrontal cortex are critical for hits, which are accurate responses on signal trials14,15. In contrast, GABAergic neurons in this region are thought to mediate performance during correct rejections (CRs), which are accurate responses on non-signal trials16. Once the basic circuit for this task was established, factors that modulate this circuit to impair attention ranging from stress hormones to neurotoxic proteins have been identified17,18. Collectively, these studies highlight the utility of SAT.
One limitation to implementing SAT in the laboratory is that the original procedure requires operant chambers permanently configured for the task, with a center panel light and two extendable levers, one designated for hits and one for CRs10. On a signal trial, the panel light briefly illuminates and then levers extend to indicate a 4 s response window. During that window, if the designated hit lever is pressed, then the rat receives a reward (either food or water). Incorrect lever presses on signal trials, known as misses, are not rewarded. On non-signaled trials, the panel light remains off, then levers are extended. While a CR is rewarded, incorrect lever presses on non-signaled trials, known as false alarms, are not rewarded. A failure to make any response during the response window counts as an omission. To expand the availability of SAT, we recently modified the task for touchscreen operant chambers, in which one wall is a touchscreen that can both display visual stimuli and record nose-poke responses19. Touchscreen chambers are becoming popular because of their versatility to run a variety of tasks (e.g., paired associate learning, reversal learning, etc.) with one piece of equipment20. Similar to other touchscreen procedures20,21,22, our adaptation of SAT requires the use of an opaque plastic touchscreen cover, called a mask, with holes cut into it. A central, circular hole allows for the presentation of a signal by presenting a white stimulus on the screen behind it, and two square response areas, one designated for hits and one for CRs, allow the rat to make touch responses19. In the traditional chambers, the 4-s response window is typically indicated with the presentation of the levers, but a previous study demonstrated that a tone can also be used to signal the response window23. In touchscreen SAT, we similarly signal the response window with a brief tone. Other training parameters (e.g., number of trials, intertrial interval, etc.) are kept similar between traditional and touchscreen SAT. We previously assessed performance between the traditional and touchscreen SAT versions and found that it was comparable, suggesting that touchscreen SAT is a valid way to measure sustained attention19. The touchscreen modification makes SAT more versatile because it can now be adapted for widespread use in touchscreen operant boxes.
The present protocol details how to run touchscreen SAT in the laboratory. The training schedules have been slightly altered from our previous report of the task19 to optimize acquisition time in female rats, which, unlike males, had difficulty advancing through the previous schedules24. Results illustrating typical performance in male and female rats are included, along with tips for troubleshooting issues with the task.

<table>
	<tbody>
		<tr>
			<td>Bussey-Saksida Rat Touch Screen Chambers Easy-Install System</td>
			<td>Lafayette Instrument</td>
			<td>80604-20</td>
			<td>Includes: Touch Screen, Chamber base with perforated floors, Large Feeder Reward Area (44.5mm wide x 92.5mm high), Speaker, Houselight, Tone Generator, SAC; Trapezoidal animal working area is 126mm wide at the Feeder, 240mm wide and 332 mm deep at the Screen, and 300 mm in height</td>
		</tr>
		<tr>
			<td>Sound Attenuation Cubicles (SAC)</td>
			<td>Lafayette Instrument</td>
			<td>80604-20</td>
			<td>Attenuation to approximately 35dB; 38kg in weight; External dimensions: 600mm wide x 670mm tall x 352mm deep; Internal dimensions: 540mm wide x 610mm tall x 532mm deep</td>
		</tr>
		<tr>
			<td>Abet II Software for Touch Screens</td>
			<td>Lafayette Instrument</td>
			<td>89505</td>
			<td>Version 2.19</td>
		</tr>
		<tr>
			<td>Whisker Multimedia</td>
			<td>Lafayette Instrument</td>
			<td>80698-1</td>
			<td>Required for Abet II Touch Operation</td>
		</tr>
		<tr>
			<td>Pellet Dispenser</td>
			<td>Lafayette Instrument</td>
			<td>80209-45</td>
			<td>45mg Interchangeable Pellet Size Wheel</td>
		</tr>
		<tr>
			<td>Camera</td>
			<td>Lafayette Instrument</td>
			<td>80600-CAM</td>
			<td>Filtered and focused for IR light</td>
		</tr>
		<tr>
			<td>Microsoft Windows</td>
			<td>Microsoft</td>
			<td></td>
			<td>Windows 7-64 bit recommended</td>
		</tr>
		<tr>
			<td>Controller PC-Touch Screen Chambers</td>
			<td>Lafayette Instrument</td>
			<td>88530</td>
			<td>Dual Core Pentinum Processor; 2.5 GHz or greater; keyboard, mouse, and monitor; Installed PCI card, cable and expansion; Four RS232 ports; Four VGA ports</td>
		</tr>
		<tr>
			<td>Dustless Precision Pellets</td>
			<td>BioServe</td>
			<td>F0165</td>
			<td>45 mg</td>
		</tr>
		<tr>
			<td>Black Acrylic Mask</td>
			<td>Everything Plastic</td>
			<td>Custom Product</td>
			<td>Black polycarbonate with one matte finish side, 3.18 mm thick; Central circular opening, 28.58 mm diameter, 107.95 mm from the bottom, centered between the left and right side; Two square response areas, 28.57 mm x 28.57mm each positioned below and off center, one 85.725 mm from the left and one 85.725 mm from right side, and both 34.925 mm from the bottom.</td>
		</tr>
		<tr>
			<td>Utility Cart</td>
			<td>Fisher Scientific</td>
			<td>11-954-754</td>
			<td>30.75 in. x 18.38 in x 33 in</td>
		</tr>
		<tr>
			<td>Black towel</td>
			<td></td>
			<td></td>
			<td>Large enough to cover cages for animal transport</td>
		</tr>
		<tr>
			<td>Headlights with red lights</td>
			<td>Energizer</td>
			<td>HDL33A2E</td>
			<td>LED white and red light</td>
		</tr>
	</tbody>
</table>

touchscreen sustained attention task (sat) for rats

Sustained attention is the ability to monitor intermittent and unpredictable events over a prolonged period of time. This attentional process subserves other aspects of cognition and is disrupted in certain neurodevelopmental, neuropsychiatric, and neurodegenerative disorders. Thus, it is clinically important to identify mechanisms that impair and improve sustained attention. Such mechanisms are often first discovered using rodent models. Therefore, several behavior procedures for testing aspects of sustained attention have been developed for rodents. One, first described by McGaughy and Sarter (1995), called the sustained attention task (SAT), trains rats to distinguish between signal (i.e., brief light presentation) and non-signal trials. The signals are short and thus require careful attention to be perceived. Attentional demands can be increased further by introducing a distractor (e.g., flashing houselight). We have modified this task for touchscreen operant chambers, which are configured with a touchscreen on one wall that can present stimuli and record responses. Here we detail our protocol for SAT in touchscreen chambers. Additionally, we present standard measures of performance in male and female Sprague-Dawley rats. Comparable performance on this task in both sexes highlights its use for attention studies, especially as more researchers are including female rodents in their experimental design. Moreover, the easy implementation of SAT for the increasingly popular touchscreen chambers increases its utility.

For most attention studies, rats are trained to criteria on SAT and then manipulations to disrupt or improve attention are performed. Acquisition data is not typically presented, but we do so here to illustrate rates of acquisition in male and female Sprague-Dawley rats. To this end, we quantified the median number of days to reach criteria on SAT (starting on the Nose Poke Phase). Note that a few rats never made it to criteria (n = 5 males, and n = 1 female). The median days that it took...

Watch this Scientific Journal Video about Touchscreen Sustained Attention Task SAT for Rats at JoVE.com

Touchscreen Sustained Attention Task SAT for Rats

Sustained attention, or continuously monitoring situations for intermittent and unpredictable events, is a critical aspect of cognition. Here we detail how to test sustained attention in rats using touchscreen operant chambers. We demonstrate comparable performance in male and female rats, making this task useful for studying attention in both sexes.

Touchscreen Sustained Attention Task (SAT) for Rats

Sustained attention is the ability to monitor intermittent and unpredictable events over a prolonged period of time. This attentional process subserves ...

touchscreen-sustained-attention-task-sat-for-rats

Research

JoVE Journal

Neuroscience

9.7K Views.  Temple University. Sustained attention, or continuously monitoring situations for intermittent and unpredictable events, is a critical aspect of cognition. Here we detail how to test sustained attention in rats using touchscreen operant chambers. We demonstrate comparable performance in male and female rats, making this task useful for studying attention in both sexes.

Video: Touchscreen Sustained Attention Task SAT for Rats

Assessment of Ultrasonic Vocalizations During Drug Self-administration in Rats

Drug self-administration procedures are commonly used to study behavioral and neurochemical changes associated with human drug abuse, addiction and relapse. Various types of behavioral activity are commonly utilized as measures of drug motivation in animals. However, a crucial component of drug abuse relapse in abstinent cocaine users is "drug craving", which is difficult to model in animals, as it often occurs in the absence of overt behaviors. Yet, it is possible that a class of ultrasonic vocalizations (USVs) in rats may be a useful marker for affective responses to drug administration, drug anticipation and even drug craving. Rats vocalize in ultrasonic frequencies that serve as a communicatory function and express subjective emotional states. Several studies have shown that different call frequency ranges are associated with negative and positive emotional states. For instance, high frequency calls ("50-kHz") are associated with positive affect, whereas low frequency calls ("22-kHz") represent a negative emotional state. This article describes a procedure to assess rat USVs associated with daily cocaine self-administration. For this procedure, we utilized standard single-lever operant chambers housed within sound-attenuating boxes for cocaine self-administration sessions and utilized ultrasonic microphones, multi-channel recording hardware and specialized software programs to detect and analyze USVs. USVs measurements reflect emotionality of rats before, during and after drug availability and can be correlated with commonly assessed drug self-administration behavioral data such lever responses, inter-response intervals and locomotor activity. Since USVs can be assessed during intervals prior to drug availability (e.g., anticipatory USVs) and during drug extinction trials, changes in affect associated with drug anticipation and drug abstinence can also be determined. In addition, determining USV changes over the course of short- and long-term drug exposure can provide a more detailed interpretation of drug exposure effects on affective functioning.

Drug self-administration and ultrasonic vocalizations (USV) are used as behavioral assessments in animal research, but rarely in combination. The purpose of this article is to describe the advantages of recording USVs during drug self-administration procedures to assess affective responses to drug experience.

Drug self-administration procedures are commonly used to study behavioral and neurochemical changes associated with human drug abuse, addiction and ...

A Procedure for Studying the Footshock-Induced Reinstatement of Cocaine Seeking in Laboratory Rats

The most insidious aspect of drug addiction is the high propensity for relapse. Animal models of relapse, known as reinstatement procedures, have been used extensively to study the neurobiology and phenomenology of relapse to drug use. Although procedural variations have emerged over the past several decades, the most conventional reinstatement procedures are based on the drug self-administration (SA) model. In this model, an animal is trained to perform an operant response to obtain drug. Subsequently, the behavior is extinguished by withholding response-contingent reinforcement. Reinstatement of drug seeking is then triggered by a discrete event, such as an injection of the training drug, re-exposure to drug-associated cues, or exposure to a stressor 1.
Reinstatement procedures were originally developed to study the ability of acute non-contingent exposure to the training drug to reinstate drug seeking in rats and monkeys 1, 2. Reinstatement procedures have since been modified to study the role of environmental stimuli, including drug-associated cues and exposure to various forms of stress, in relapse to drug seeking 1, 3, 4.
Over the past 15 years, a major focus of the reinstatement literature has been on the role of stress in drug relapse. One of the most commonly used forms of stress for studying this relationship is acute exposures to mild, intermittent, electric footshocks. The ability of footshock stress to induce reinstatement of drug seeking was originally demonstrated by Shaham and colleagues (1995) in rats with a history of intravenous heroin SA5. Subsequently, the effect was generalized to rats with histories of intravenous cocaine, methamphetamine, and nicotine SA, as well as oral ethanol SA 3, 6.
Although footshock-induced reinstatement of drug seeking can be achieved reliably and robustly, it is an effect that tends to be sensitive to certain parametrical variables. These include the arrangement of extinction and reinstatement test sessions, the intensity and duration of footshock stress, and the presence of drug-associated cues during extinction and testing for reinstatement. Here we present a protocol for footshock-induced reinstatement of cocaine seeking that we have used with consistent success to study the relationship between stress and cocaine seeking.

Animal models of relapse, known as reinstatement procedures, have been used extensively to study the role of stress in relapse to drug seeking. Here, we report on a method for inducing the reinstatement of cocaine seeking in laboratory rats via acute exposures to mild, intermittent electric footshock.

The most insidious aspect of drug addiction is the high propensity for relapse.  Animal models of relapse, known as reinstatement procedures, have been ...

Correlating Behavioral Responses to fMRI Signals from Human Prefrontal Cortex: Examining Cognitive Processes Using Task Analysis

The aim of this methods paper is to describe how to implement a neuroimaging technique to examine complementary brain processes engaged by two similar tasks. Participants' behavior during task performance in an fMRI scanner can then be correlated to the brain activity using the blood-oxygen-level-dependent signal. We measure behavior to be able to sort correct trials, where the subject performed the task correctly and then be able to examine the brain signals related to correct performance. Conversely, if subjects do not perform the task correctly, and these trials are included in the same analysis with the correct trials we would introduce trials that were not only for correct performance. Thus, in many cases these errors can be used themselves to then correlate brain activity to them. We describe two complementary tasks that are used in our lab to examine the brain during suppression of an automatic responses: the stroop1 and anti-saccade tasks. The emotional stroop paradigm instructs participants to either report the superimposed emotional 'word' across the affective faces or the facial 'expressions' of the face stimuli1,2. When the word and the facial expression refer to different emotions, a conflict between what must be said and what is automatically read occurs. The participant has to resolve the conflict between two simultaneously competing processes of word reading and facial expression. Our urge to read out a word leads to strong 'stimulus-response (SR)' associations; hence inhibiting these strong SR's is difficult and participants are prone to making errors. Overcoming this conflict and directing attention away from the face or the word requires the subject to inhibit bottom up processes which typically directs attention to the more salient stimulus. Similarly, in the anti-saccade task3,4,5,6, where an instruction cue is used to direct only attention to a peripheral stimulus location but then the eye movement is made to the mirror opposite position. Yet again we measure behavior by recording the eye movements of participants which allows for the sorting of the behavioral responses into correct and error trials7 which then can be correlated to brain activity. Neuroimaging now allows researchers to measure different behaviors of correct and error trials that are indicative of different cognitive processes and pinpoint the different neural networks involved.

The goal of our research is to correlate behavior to brain activity. Accurate behavioral measures and imaging techniques allow us to elucidate brain-behavior relationships.

The aim of this methods paper is to describe how to implement a neuroimaging technique to examine complementary brain processes engaged by two similar ...

A General Method for Evaluating Incubation of Sucrose Craving in Rats

For someone on a food-restricted diet, food craving in response to food-paired cues may serve as a key behavioral transition point between abstinence and relapse to food taking 1. Food craving conceptualized in this way is akin to drug craving in response to drug-paired cues. A rich literature has been developed around understanding the behavioral and neurobiological determinants of drug craving; we and others have been focusing recently on translating techniques from basic addiction research to better understand addiction-like behaviors related to food 2-4.
As done in previous studies of drug craving, we examine sucrose craving behavior by utilizing a rat model of relapse. In this model, rats self-administer either drug or food in sessions over several days. In a session, lever responding delivers the reward along with a tone+light stimulus. Craving behavior is then operationally defined as responding in a subsequent session where the reward is not available. Rats will reliably respond for the tone+light stimulus, likely due to its acquired conditioned reinforcing properties 5. This behavior is sometimes referred to as sucrose seeking or cue reactivity. In the present discussion we will use the term "sucrose craving" to subsume both of these constructs.
In the past decade, we have focused on how the length of time following reward self-administration influences reward craving. Interestingly, rats increase responding for the reward-paired cue over the course of several weeks of a period of forced-abstinence. This "incubation of craving" is observed in rats that have self-administered either food or drugs of abuse 4,6. This time-dependent increase in craving we have identified in the animal model may have great potential relevance to human drug and food addiction behaviors.
Here we present a protocol for assessing incubation of sucrose craving in rats. Variants of the procedure will be indicated where craving is assessed as responding for a discrete sucrose-paired cue following extinction of lever pressing within the sucrose self-administration context (Extinction without cues) or as responding for sucrose-paired cues in a general extinction context (Extinction with cues).

Responding for food or drug-paired cues increases over the course of a period of abstinence and this may relate to an increased susceptibility to relapse behaviors. Here we detail a procedure for evaluating this "incubation of craving" in rats that have self-administered sucrose.

For someone on a food-restricted diet, food craving in response to food-paired cues may serve as a key behavioral transition point between abstinence and ...

Mapping Cortical Dynamics Using Simultaneous MEG/EEG and Anatomically-constrained Minimum-norm Estimates: an Auditory Attention Example

Magneto- and electroencephalography (MEG/EEG) are neuroimaging techniques that provide a high temporal resolution particularly suitable to investigate the cortical networks involved in dynamical perceptual and cognitive tasks, such as attending to different sounds in a cocktail party. Many past studies have employed data recorded at the sensor level only, i.e., the magnetic fields or the electric potentials recorded outside and on the scalp, and have usually focused on activity that is time-locked to the stimulus presentation. This type of event-related field / potential analysis is particularly useful when there are only a small number of distinct dipolar patterns that can be isolated and identified in space and time. Alternatively, by utilizing anatomical information, these distinct field patterns can be localized as current sources on the cortex. However, for a more sustained response that may not be time-locked to a specific stimulus (e.g., in preparation for listening to one of the two simultaneously presented spoken digits based on the cued auditory feature) or may be distributed across multiple spatial locations unknown a priori, the recruitment of a distributed cortical network may not be adequately captured by using a limited number of focal sources.
Here, we describe a procedure that employs individual anatomical MRI data to establish a relationship between the sensor information and the dipole activation on the cortex through the use of minimum-norm estimates (MNE). This inverse imaging approach provides us a tool for distributed source analysis. For illustrative purposes, we will describe all procedures using FreeSurfer and MNE software, both freely available. We will summarize the MRI sequences and analysis steps required to produce a forward model that enables us to relate the expected field pattern caused by the dipoles distributed on the cortex onto the M/EEG sensors. Next, we will step through the necessary processes that facilitate us in denoising the sensor data from environmental and physiological contaminants. We will then outline the procedure for combining and mapping MEG/EEG sensor data onto the cortical space, thereby producing a family of time-series of cortical dipole activation on the brain surface (or "brain movies") related to each experimental condition. Finally, we will highlight a few statistical techniques that enable us to make scientific inference across a subject population (i.e., perform group-level analysis) based on a common cortical coordinate space.

We use magneto- and electroencephalography (MEG/EEG), combined with anatomical information captured by magnetic resonance imaging (MRI), to map the dynamics of the cortical network associated with auditory attention.

Magneto- and electroencephalography (MEG/EEG) are neuroimaging techniques that provide a high temporal resolution particularly suitable to investigate the ...

Generation of Topically Transgenic Rats by In utero Electroporation and In vivo Bioluminescence Screening

In utero electroporation (IUE) is a technique which allows genetic modification of cells in the brain for investigating neuronal development. So far, the use of IUE for investigating behavior or neuropathology in the adult brain has been limited by insufficient methods for monitoring of IUE transfection success by non-invasive techniques in postnatal animals. 
 For the present study, E16 rats were used for IUE. After intraventricular injection of the nucleic acids into the embryos, positioning of the tweezer electrodes was critical for targeting either the developing cortex or the hippocampus. 
 Ventricular co-injection and electroporation of a luciferase gene allowed monitoring of the transfected cells postnatally after intraperitoneal luciferin injection in the anesthetized live P7 pup by in vivo bioluminescence, using an IVIS Spectrum device with 3D quantification software. 
 Area definition by bioluminescence could clearly differentiate between cortical and hippocampal electroporations and detect a signal longitudinally over time up to 5 weeks after birth. This imaging technique allowed us to select pups with a sufficient number of transfected cells assumed necessary for triggering biological effects and, subsequently, to perform behavioral investigations at 3 month of age. As an example, this study demonstrates that IUE with the human full length DISC1 gene into the rat cortex led to amphetamine hypersensitivity. Co-transfected GFP could be detected in neurons by post mortem fluorescence microscopy in cryosections indicating gene expression present at &ge;6 months after birth.
 We conclude that postnatal bioluminescence imaging allows evaluating the success of transient transfections with IUE in rats. Investigations on the influence of topical gene manipulations during neurodevelopment on the adult brain and its connectivity are greatly facilitated. For many scientific questions, this technique can supplement or even replace the use of transgenic rats and provide a novel technology for behavioral neuroscience.

Generation of Topically Transgenic Rats by In utero Electroporation and In vivo Bioluminescence Screening

Genes can be manipulated during development of the cortex or the hippocampus of the rat via in utero electroporation (IUE) at E16, to enable fast and targeted modifications in neuronal connectivity for later studies of behavior or neuropathology in adult animals. Postnatal in vivo imaging for control of IUE success is performed by bioluminescence of activating co-transfected luciferase.

 In utero electroporation (IUE) is a technique which allows genetic modification of cells in the brain for investigating neuronal development. So far, the ...

Unilateral Pyramidotomy of the Corticospinal Tract in Rats for Assessment of Neuroplasticity-inducing Therapies

The corticospinal tract (CST) can be completely severed unilaterally in the medullary pyramids of the rodent brainstem. The CST is a motor tract that has great importance for distal muscle control in humans and, to a lesser extent, in rodents. A unilateral cut of one pyramid results in loss of CST innervation of the spinal cord mainly on the contralateral side of the spinal cord leading to transient motor disability in the forelimbs and sustained loss of dexterity. Ipsilateral projections of the corticospinal tract are minor. We have refined our surgical method to increase the chances of lesion completeness. We describe postsurgical care. Deficits on the Montoya staircase pellet reaching test and the horizontal ladder test shown here are detected up to 8 weeks postinjury. Deficits on the cylinder rearing test are only detected transiently. Therefore, the cylinder test may only be suitable for detection of short term recovery. We show how, electrophysiologically and anatomically, one may assess lesions and plastic changes. We also describe how to analyse fibers from the uninjured CST sprouting across the midline into the deprived areas. It is challenging to obtain &#62;90% complete lesions consistently due to the proximity to the basilar artery in the medulla oblongata and survival rates can be low. Alternative surgical approaches and behavioural testing are described in this protocol. The pyramidotomy model is a good tool for assessing neuroplasticity-inducing treatments, which increase sprouting of intact fibers after injury.

The corticospinal tract, one of the major sensorimotor tracts, can be lesioned unilaterally in the rodent brainstem in order to test neuroplasticity-inducing therapies for the central nervous system. This surgical procedure (&#8220;pyramidotomy&#8221;) and postoperative assessments are described in this protocol.

The corticospinal tract (CST) can be completely severed unilaterally in the medullary pyramids of the rodent brainstem. The CST is a motor tract that has ...

Conducting Concurrent Electroencephalography and Functional Near-Infrared Spectroscopy Recordings with a Flanker Task

Concurrent EEG and fNIRS recordings offer an excellent opportunity to gain a full understanding of the neural mechanism of cognitive processing by inspecting the relationship between the neural and hemodynamic signals. EEG is an electrophysiological technology that can measure the rapid neuronal activity of the cortex, whereas fNIRS relies on the hemodynamic responses to infer brain activation. The combination of EEG and fNIRS neuroimaging techniques can identify more features and reveal more information associated with the functioning of the brain. In this protocol, fused EEG-fNIRS measurements were performed for concurrent recordings of evoked-electrical potentials and hemodynamic responses during a Flanker task. In addition, the critical steps for setting up the hardware and software system as well as the procedures for data acquisition and analysis were provided and discussed in detail. It is expected that the present protocol can pave a new avenue for improving the understanding of the neural mechanisms underlying various cognitive processes by using the EEG and fNIRS signals.

The present protocol describes how to perform concurrent EEG and fNIRS recordings and how to inspect the relationship between the EEG and fNIRS data.&#160;

Concurrent EEG and fNIRS recordings offer an excellent opportunity to gain a full understanding of the neural mechanism of cognitive processing by ...

Event Related Potentials (ERPs) and other EEG Based Methods for Extracting Biomarkers of Brain Dysfunction: Examples from Pediatric Attention Deficit/Hyperactivity Disorder (ADHD)

Neuropsychiatric diagnoses like ADHD are based on subjective methods like interviews, rating scales and observations. There is a need for more brain-based supplements. Stimulant medication is the most common treatment for ADHD. Clinically useful predictors of response have so far not been reported. The aim of this paper is to describe the EEG based methods we apply to extract potential biomarkers for brain dysfunction. Examples relate to biomarkers for pediatric ADHD, and prediction of medication response. The main emphasis is on Event Related Potentials (ERPs).
A nineteen channel EEG is recorded during a 3 min eyes-opened task, a 3 min eyes-closed task, and a 20 min cued visual GO/NOGO task (VCPT). ERPs are recorded during this task. The goal of the ERP protocol is to extract biomarkers of assumed brain dysfunctions that significantly differentiate between a patient group and healthy controls. The protocol includes recording during standard conditions and artifact correction. ERP waves can be used or transformed into latent components. The components of the patient group are compared with controls, empathizing components that, when compared, show relatively high effect sizes. Sub-groups of the patients are selected on the basis of the cluster analysis in the space of the components. Treatment procedure (such as medication, tDCS or neurofeedback protocol) can be applied and the changes in components related to treatment in the subgroups are observed, forming the basis for clinical recommendations.
The methods described were applied in a study of 87 pediatric ADHD patients. The index of medication response discriminated significantly between responders and non-responders with a large, and clinically meaningful effect size (d = 1.84). In an ongoing study comparing ADHD children with matched controls, several variables discriminate significantly between patients and controls. The global index will exceed d = .8. The EEG based methods described here could be clinically meaningful.

Event Related Potentials ERPs and other EEG Based Methods for Extracting Biomarkers of Brain Dysfunction: Examples from Pediatric Attention Deficit/Hyperactivity Disorder ADHD

EEG-methods are applied for extracting biomarkers of brain dysfunctions. The focus is on multi-channel event-related potentials (ERPs) recorded in a cued GO/NOGO task. Non-brain artifacts are corrected and ERPs are compared with the normative data. Examples relate to biomarkers for ADHD diagnosis and prediction of medication response.

Neuropsychiatric diagnoses like ADHD are based on subjective methods like interviews, rating scales and observations. There is a need for more brain-based ...

Preparation of Peripheral Nerve Stimulation Electrodes for Chronic Implantation in Rats

Peripheral nerve cuff electrodes have long been used in the neurosciences and related fields for stimulation of, for example, vagus or sciatic nerves. Several recent studies have demonstrated the effectiveness of chronic VNS in enhancing central nervous system plasticity to improve motor rehabilitation, extinction learning, and sensory discrimination. Construction of chronically implantable devices for use in such studies is challenging due to rats&#8217; small size, and typical protocols require extensive training of personnel and time-consuming microfabrication methods. Alternatively, commercially available implantable cuff electrodes can be purchased at a significantly higher cost. In this protocol, we present a simple, low-cost method for construction of small, chronically implantable peripheral nerve cuff electrodes for use in rats. We validate the short and long-term reliability of our cuff electrodes by demonstrating that VNS in ketamine/xylazine anesthetized rats produces decreases in breathing rate consistent with activation of the Hering-Breuer reflex, both at the time of implantation and up to 10 weeks after device implantation. We further demonstrate the suitability of the cuff electrodes for use in chronic stimulation studies by pairing VNS with skilled lever press performance to induce motor cortical map plasticity.

Existing approaches for constructing chronically implantable peripheral nerve cuff electrodes for use in small rodents often require specialized equipment and/or highly trained personnel. In this protocol we demonstrate a simple, low-cost approach for fabricating chronically implantable cuff electrodes, and demonstrate their effectiveness for vagus nerve stimulation (VNS) in rats.

Peripheral nerve cuff electrodes have long been used in the neurosciences and related fields for stimulation of, for example, vagus or sciatic nerves. ...