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OP 2. Transfer of cognitive training across magnitude dimensions achieved with concurrent brain stimulation of the parietal lobe
Society Proceedings / Clinical Neurophysiology 124 (2013) e39–e187
Methods: Slow oscillatory direct transcranial current stimulation (so-tDCS) was applied over the frontal cortex of rats during slowwave sleep (SWS) and its effects on memory consolidation in the one-trial object-place recognition task (OPR) were examined. The OPR is a spatial memory task, and has been shown to depend critically on intact hippocampal function (Bussey et al., 2000; Mumby et al., 2002). It does not involve stressful procedures or food deprivation; it is based on the rodents’ natural behavior, i.e., novelty preference (Ennaceur et al., 1997) and allows for intra-subject testing for stimulation and sham conditions. Previous findings showed the dependency of this task on sleep containing a large amount of slow wave activity within the retention interval (Binder et al., 2012; Inostroza et al., 2012). In a within subject design, 12 rats received one so-tDCS over the frontal cortex and one sham-tDCS session immediately after learning during early SWS. 24 h after learning, the test session in the OPR task took place to investigate the effects of so-tDCS on long-term memory. Results: As depicted in Fig. 1, animals were only able to solve the task following so-tDCS, but failed to do so in the sham condition lacking so-tDCS. EEG spectral power indicated a transitory enhancement of endogenous SO activity after cessation of so-tDCS. Conclusion: We conclude that SO play a causal role for sleep dependent memory consolidation, and state that oscillatory tDCS is a highly valuable tool to further investigate the function of endogenous cortical network activity. References Marshall L, Helgadottir H, Mölle M, Born J. Boosting slow oscillations during sleep potentiates memory. Nature 2006;444:610–3.
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Bussey TJ, Duck J, Muir JL, Aggleton JP. Distinct patterns of behavioural impairments resulting from fornix transection or neurotoxic lesions of the perirhinal and postrhinal cortices in the rat. Behav Brain Res 2000;111:187–202. Mumby DG, Gaskin S, Glenn MJ, Schramek TE, Lehmann H. Hippocampal damage and exploratory preferences in rats: memory for objects, places, and contexts. Learn Mem 2002;9:49–57. Ennaceur A, Neave N, Aggleton JP. Spontaneous object recognition and object location memory in rats: the effects of lesions in the cingulate cortices, the medial prefrontal cortex, the cingulum bundle and the fornix. Exp Brain Res 1997;113:509–19. Binder S, Baier PC, Mölle M, Inostroza M, Born J, Marshall L. Sleep enhances memory consolidation in the hippocampus-dependent object-place recognition task in rats. Neurobiol Learn Mem 2012;97:213–9. Inostroza M, Binder S, Born J. Sleep-dependency of episodic-like memory consolidation in rats. Behav Brain Res 2012. doi:10.1016/j.bbr.2012.09.011. doi:10.1016/j.clinph.2013.04.068
OP 2. Transfer of cognitive training across magnitude dimensions achieved with concurrent brain stimulation of the parietal lobe— M. Cappelletti, E. Gessaroli, R. Hithersay, M. Mitolo, R. Kanai, R. Cohn Kadosh, V. Walsh (University College London, Institute of Cognitive Neuroscience, London, United Kingdom) Question: Can training-induced changes be maintained long term and can they be extended to other related but untrained skills? Method: We (i) measured the independent and combined contribution of intensive, 5-day cognitive training and brain stimulation applied to critical and control brain region using transcranial random noise stimulation, tRNS; (ii) tested whether any improvement in a trained cognitive skill transferred onto non-trained skills; and (iii) tested the possible long-term effects of any cognitive improvement. Participants were trained on a well-known, parametricallydesigned numerosity discrimination task, requiring them to judge the most numerous of two sets i.e. the set containing more dots (see Fig. 1). Results: There was a significant improvement (on average about 18%) in performing a numerosity discrimination task following intensive and continuous repetition of the task. However, there was an even larger improvement (about 37%) when this repetition was accompanied by tRNS to brain areas that are critical for numerosity discrimination, i.e. the left and right parietal lobes. The improvement was much smaller when stimulation was not associated to cognitive training or when tRNS was applied to brain regions irrelevant for the trained task, i.e. the motor areas. Improvements in numerosity discrimination following cognitive training combined to parietal tRNS were maintained up to 16 weeks post-training. In contrast, the other experimental conditions showed no such steadiness of learning. When intense cognitive training was associated to parietal tRNS, improvement in number acuity transferred to the ability to discriminate other types of quantity, specifically time and space that are thought to share common neural and cognitive substrates with numerosity discrimination. There was no transfer to other cognitive skills such as face perception and arithmetic.
Fig. 1. Object-Place Recognition task. A) Two objects are presented in an open field during a Sample trial, and after a 24-h retention interval the same objects are presented in a Test trial with one of the objects displaced. B) Preference-Index (mean+/-SEM) for the displaced object during the Test trials for both conditions, separated for the 1st and the total 2 min of the trial. An exploration pattern above chance level is only observed in the STIM condition (black bars) but not in the SHAM condition (white bars). *p < 0.05,**p 6 0.01.
Conclusions: These results indicate that with a suitably chosen task and stimulation, cognitive training can cause large long-lasting enhancement of cognitive functions that are shared across associated tasks. doi:10.1016/j.clinph.2013.04.069
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Society Proceedings / Clinical Neurophysiology 124 (2013) e39–e187
Fig. 1. Design of the training paradigm and of the tasks used. Participants in the P, ST and PT groups were trained intensively on a numerosity discrimination task for 5 consecutive days (days 2–6) while receiving real (P & PT groups) or fake (ST group) stimulation to the parietal areas or to a control region (motor areas, MT). Prior to the training (day 1, pre-training), participants were tested with the numerosity discrimination task and with other quantity tasks (time & space discrimination), mathematical and control tasks. The same tasks were repeated at the end of the training (day 7, post-training) to test for any training-induced change, and again at week 4, 8, 12, and 16 post-training to test for any long-term training-effect.
Fig. 2. Results. (A) Performance in the numerosity discrimination task in the four groups for each of the training days, the post-training and at week 4, 8, 12 and 16 after training. Performance corresponds to the percent change of the weber fraction from pre-training. Performance in the (B) time and (C) space discrimination tasks in the four groups at posttraining and at week 4, 8, 12 and 16 after training. Performance is calculated as percent change of the just noticeable difference from pre-training.
Methods: Slow oscillatory direct transcranial current stimulation (so-tDCS) was applied over the frontal cortex of rats during slowwave sleep (SWS) and its effects on memory consolidation in the one-trial object-place recognition task (OPR) were examined. The OPR is a spatial memory task, and has been shown to depend critically on intact hippocampal function (Bussey et al., 2000; Mumby et al., 2002). It does not involve stressful procedures or food deprivation; it is based on the rodents’ natural behavior, i.e., novelty preference (Ennaceur et al., 1997) and allows for intra-subject testing for stimulation and sham conditions. Previous findings showed the dependency of this task on sleep containing a large amount of slow wave activity within the retention interval (Binder et al., 2012; Inostroza et al., 2012). In a within subject design, 12 rats received one so-tDCS over the frontal cortex and one sham-tDCS session immediately after learning during early SWS. 24 h after learning, the test session in the OPR task took place to investigate the effects of so-tDCS on long-term memory. Results: As depicted in Fig. 1, animals were only able to solve the task following so-tDCS, but failed to do so in the sham condition lacking so-tDCS. EEG spectral power indicated a transitory enhancement of endogenous SO activity after cessation of so-tDCS. Conclusion: We conclude that SO play a causal role for sleep dependent memory consolidation, and state that oscillatory tDCS is a highly valuable tool to further investigate the function of endogenous cortical network activity. References Marshall L, Helgadottir H, Mölle M, Born J. Boosting slow oscillations during sleep potentiates memory. Nature 2006;444:610–3.
e55
Bussey TJ, Duck J, Muir JL, Aggleton JP. Distinct patterns of behavioural impairments resulting from fornix transection or neurotoxic lesions of the perirhinal and postrhinal cortices in the rat. Behav Brain Res 2000;111:187–202. Mumby DG, Gaskin S, Glenn MJ, Schramek TE, Lehmann H. Hippocampal damage and exploratory preferences in rats: memory for objects, places, and contexts. Learn Mem 2002;9:49–57. Ennaceur A, Neave N, Aggleton JP. Spontaneous object recognition and object location memory in rats: the effects of lesions in the cingulate cortices, the medial prefrontal cortex, the cingulum bundle and the fornix. Exp Brain Res 1997;113:509–19. Binder S, Baier PC, Mölle M, Inostroza M, Born J, Marshall L. Sleep enhances memory consolidation in the hippocampus-dependent object-place recognition task in rats. Neurobiol Learn Mem 2012;97:213–9. Inostroza M, Binder S, Born J. Sleep-dependency of episodic-like memory consolidation in rats. Behav Brain Res 2012. doi:10.1016/j.bbr.2012.09.011. doi:10.1016/j.clinph.2013.04.068
OP 2. Transfer of cognitive training across magnitude dimensions achieved with concurrent brain stimulation of the parietal lobe— M. Cappelletti, E. Gessaroli, R. Hithersay, M. Mitolo, R. Kanai, R. Cohn Kadosh, V. Walsh (University College London, Institute of Cognitive Neuroscience, London, United Kingdom) Question: Can training-induced changes be maintained long term and can they be extended to other related but untrained skills? Method: We (i) measured the independent and combined contribution of intensive, 5-day cognitive training and brain stimulation applied to critical and control brain region using transcranial random noise stimulation, tRNS; (ii) tested whether any improvement in a trained cognitive skill transferred onto non-trained skills; and (iii) tested the possible long-term effects of any cognitive improvement. Participants were trained on a well-known, parametricallydesigned numerosity discrimination task, requiring them to judge the most numerous of two sets i.e. the set containing more dots (see Fig. 1). Results: There was a significant improvement (on average about 18%) in performing a numerosity discrimination task following intensive and continuous repetition of the task. However, there was an even larger improvement (about 37%) when this repetition was accompanied by tRNS to brain areas that are critical for numerosity discrimination, i.e. the left and right parietal lobes. The improvement was much smaller when stimulation was not associated to cognitive training or when tRNS was applied to brain regions irrelevant for the trained task, i.e. the motor areas. Improvements in numerosity discrimination following cognitive training combined to parietal tRNS were maintained up to 16 weeks post-training. In contrast, the other experimental conditions showed no such steadiness of learning. When intense cognitive training was associated to parietal tRNS, improvement in number acuity transferred to the ability to discriminate other types of quantity, specifically time and space that are thought to share common neural and cognitive substrates with numerosity discrimination. There was no transfer to other cognitive skills such as face perception and arithmetic.
Fig. 1. Object-Place Recognition task. A) Two objects are presented in an open field during a Sample trial, and after a 24-h retention interval the same objects are presented in a Test trial with one of the objects displaced. B) Preference-Index (mean+/-SEM) for the displaced object during the Test trials for both conditions, separated for the 1st and the total 2 min of the trial. An exploration pattern above chance level is only observed in the STIM condition (black bars) but not in the SHAM condition (white bars). *p < 0.05,**p 6 0.01.
Conclusions: These results indicate that with a suitably chosen task and stimulation, cognitive training can cause large long-lasting enhancement of cognitive functions that are shared across associated tasks. doi:10.1016/j.clinph.2013.04.069
e56
Society Proceedings / Clinical Neurophysiology 124 (2013) e39–e187
Fig. 1. Design of the training paradigm and of the tasks used. Participants in the P, ST and PT groups were trained intensively on a numerosity discrimination task for 5 consecutive days (days 2–6) while receiving real (P & PT groups) or fake (ST group) stimulation to the parietal areas or to a control region (motor areas, MT). Prior to the training (day 1, pre-training), participants were tested with the numerosity discrimination task and with other quantity tasks (time & space discrimination), mathematical and control tasks. The same tasks were repeated at the end of the training (day 7, post-training) to test for any training-induced change, and again at week 4, 8, 12, and 16 post-training to test for any long-term training-effect.
Fig. 2. Results. (A) Performance in the numerosity discrimination task in the four groups for each of the training days, the post-training and at week 4, 8, 12 and 16 after training. Performance corresponds to the percent change of the weber fraction from pre-training. Performance in the (B) time and (C) space discrimination tasks in the four groups at posttraining and at week 4, 8, 12 and 16 after training. Performance is calculated as percent change of the just noticeable difference from pre-training.