Cryonics preserves memories: "Persistence of Long-Term Memory in Vitrified and Revived C. elegans", Vita-More & Barranco 2015 http://online.liebertpub.com/doi/pdf/10.1089/rej.2014.1636 (discussion: https://www.fightaging.org/archives/2015/04/evidence-for-long-term-memory-to-survive-vitrification-in-nematode-worms.php)
I don't think I can exaggerate how important this is: cryonics has now shown psychological continuity in an organism with enough of a mind to have long-term memory and learning. Cryonics now works in principle! People are going to try to minimize this and argue that maybe human brains are special snowflakes or that the procedure doesn't scale up to human brains, but the former is the same kind of desperate pleading we saw with genetics & intelligence where nurturists fought every step of the way for a century until finally they were buried with GWASes (and still haven't admitted they were wrong about everything) and the latter is merely quibbling over details. (Important details but compared to the question of whether cryonics works at all, details.)
Excerpts:
"Can memory be retained after cryopreservation? Our research has attempted to answer this long-standing question by using the nematode worm Caenorhabditis elegans (C. elegans), a well-known model organism for biological research that has generated revolutionary findings but has not been tested for memory retention after cryopreservation. Our study’s goal was to test C. elegans’ memory recall after vitrification and reviving. Using a method of sensory imprinting in the young C. elegans we established that learning acquired through olfactory cues shapes the animal’s behavior and the learning is retained at the adult stage after vitrification. Our research method included olfactory imprinting with the chemical benzaldehyde (C6H5CHO) for phase-sense olfactory imprinting at the L1 stage, the fast cooling SafeSpeed method for vitrification at the L2 stage, reviving, and a chemotaxis assay for testing memory retention of learning at the adult stage. Our results in testing memory retention after cryopreservation show that the mechanisms that regulate the odorant imprinting (a form of long-term memory) in C. elegans have not been modified by the process of vitrification or by slow freezing.
Our study addresses the specific interest that long or short-term memories of cryopreserved and revived animals have not been tested. The organism of choice to explore this question is the C. elegans because it is the only organism in which both the cryopreservation and revival have been demonstrated, and there is a well-defined assay of learning.
Attached to this project and as an extra goal, we also evaluated the persistence of memory using the traditional protocol of cryopreservation of C. elegans by slow freezing. 2
One method for training and testing learning of the worms is to expose them to a specific chemical compound over a restricted period of time with the presence or absence of food to create a pattern of behavior. When encountering the chemical compound at later times, the worms’ level of response (memory retention) is tested and evaluated by a chemotaxis migration assay. 9,12 In their findings of associative short-term memory, Kauffman, et al. 12 show that after C. elegans are exposed to the chemoattractant butanone, the worms’ memory response starts to decrease one hour after exposure. In their findings on long-term memory, Remy and Hobert 9 show that after C. elegans are exposed to attractant chemicals such as benzaldehyde at the early larval stage, the worms’ memory response in the adult stage continues to be retained after five days, or 120 hours, for phase-sense learning, referred to as imprinting.
The control group consisted of eight sets of 100 or more worms for each study
Cryopreservation by slow freezing was performed one day after olfactory imprinting. Based on the method of Brenner 2 , the worms at the L2 and L3 stages were introduced into a cryovial (cryogenic tube) with the traditional mix of cryoprotectant for slow freezing at 15% v/v Glycerol in M9 Buffer (3g KH 2 PO 4 , 6g Na 2 HPO 4 , 5g NaCl, 1ml 1M MgSO 4 , H 2 O to 1 liter). The cryovials were transferred to a -80oC freezer for two weeks. After two weeks, the worms were transferred to a petri dish with a lawn of E. coli OP50.
in the lid of the square dish, three drops of H 2 O d (4μl each one) were placed. On the other side of the square dish, in the area with value 6, the same drops (1μl each) of sodium azide 1M were placed; however, the only difference was that on the lid of the dish we put three drops of 1% benzaldehyde (1/100 diluted in H 2 O d ) (Supplementary Figure 1 of Remy and Hobert). 9
We used a platinum wire to select and pick up individual worms from a petri dish with E. coli OP50, transferred the worms to a petri dish without food, and held for 15 minutes. Then, 20 worms were transferred along the centerline of the square dish. The worms were counted every 15 minutes. At one hour, we had accumulated 80 values (each value designated the area where was the worms were in that moment), and we calculated a migration report, which Remy and Hobert 9 referred to as the Migration Index (MI).
The trained worms (worms imprinted with benzaldehyde) preferred areas 5 and 6 on the square petri dish, close to the benzaldehyde drops, and the untrained worms preferred areas 1 and 2, demonstrating a native attraction to the benzaldehyde (Figure 1). The mean of the MI was higher and very similar in all the studies with trained worms. The studies with untrained worms were also similar (Figure 1). The highest value of the MI was 4.23 and was obtained with trained and unvitrified worms and the lowest value was 1.34 in the untrained and not vitrified worms (Table 2). In general, the response of the trained worms to the benzaldehyde was double that of the untrained worms, whether they were cryopreserved or not. The variance of MI did not show homogeneity (Levene = 2.920, df1= 9, df2= 60, P=0.006) and the comparison of the media through one factor-ANOVA showed differences between groups (F=26.061, P=0.000). The Tahame test, for comparisons in pairs, showed differences between the two groups: trained and untrained worms, and no differences between the studies inside of each group (Supplementary Table 1). There were no differences between trained and vitrified worms and trained and not vitrified worms (Tahame, i-j=0.72, P=0.305). Also, there were no differences between untrained and slow freezing and trained and slow freezing (Tahame, i-j=0.24, p=0.138). Both methods of cryopreservation did not show differences in the MI average of trained worms and were also similar to the migration index of trained and worms that were not cryopreserved (Figure 1 and supplementary Table 1).
We demonstrated that cryoprotectants used in both the slow freezing and vitrification processes do not affect, alter, or change the mechanism that regulates the olfactory imprinting and long-term memory (Figure 1). Secondly, we determined that the process of cryopreservation methods of slow freezing or vitrification do not affect, alter, or change this mechanism (Figure 1). We also demonstrated that the results of the MI average obtained for the trained and untrained worms are similar to the results of the original authors of the odorant imprinting protocol. 9
The study shows the first results related to the persistence of memory after vitrification. Prior to this study, no other study or methodology had existed to carry out this project or a similar project."
#cryonics #transhumanism
I don't think I can exaggerate how important this is: cryonics has now shown psychological continuity in an organism with enough of a mind to have long-term memory and learning. Cryonics now works in principle! People are going to try to minimize this and argue that maybe human brains are special snowflakes or that the procedure doesn't scale up to human brains, but the former is the same kind of desperate pleading we saw with genetics & intelligence where nurturists fought every step of the way for a century until finally they were buried with GWASes (and still haven't admitted they were wrong about everything) and the latter is merely quibbling over details. (Important details but compared to the question of whether cryonics works at all, details.)
Excerpts:
"Can memory be retained after cryopreservation? Our research has attempted to answer this long-standing question by using the nematode worm Caenorhabditis elegans (C. elegans), a well-known model organism for biological research that has generated revolutionary findings but has not been tested for memory retention after cryopreservation. Our study’s goal was to test C. elegans’ memory recall after vitrification and reviving. Using a method of sensory imprinting in the young C. elegans we established that learning acquired through olfactory cues shapes the animal’s behavior and the learning is retained at the adult stage after vitrification. Our research method included olfactory imprinting with the chemical benzaldehyde (C6H5CHO) for phase-sense olfactory imprinting at the L1 stage, the fast cooling SafeSpeed method for vitrification at the L2 stage, reviving, and a chemotaxis assay for testing memory retention of learning at the adult stage. Our results in testing memory retention after cryopreservation show that the mechanisms that regulate the odorant imprinting (a form of long-term memory) in C. elegans have not been modified by the process of vitrification or by slow freezing.
Our study addresses the specific interest that long or short-term memories of cryopreserved and revived animals have not been tested. The organism of choice to explore this question is the C. elegans because it is the only organism in which both the cryopreservation and revival have been demonstrated, and there is a well-defined assay of learning.
Attached to this project and as an extra goal, we also evaluated the persistence of memory using the traditional protocol of cryopreservation of C. elegans by slow freezing. 2
One method for training and testing learning of the worms is to expose them to a specific chemical compound over a restricted period of time with the presence or absence of food to create a pattern of behavior. When encountering the chemical compound at later times, the worms’ level of response (memory retention) is tested and evaluated by a chemotaxis migration assay. 9,12 In their findings of associative short-term memory, Kauffman, et al. 12 show that after C. elegans are exposed to the chemoattractant butanone, the worms’ memory response starts to decrease one hour after exposure. In their findings on long-term memory, Remy and Hobert 9 show that after C. elegans are exposed to attractant chemicals such as benzaldehyde at the early larval stage, the worms’ memory response in the adult stage continues to be retained after five days, or 120 hours, for phase-sense learning, referred to as imprinting.
The control group consisted of eight sets of 100 or more worms for each study
Cryopreservation by slow freezing was performed one day after olfactory imprinting. Based on the method of Brenner 2 , the worms at the L2 and L3 stages were introduced into a cryovial (cryogenic tube) with the traditional mix of cryoprotectant for slow freezing at 15% v/v Glycerol in M9 Buffer (3g KH 2 PO 4 , 6g Na 2 HPO 4 , 5g NaCl, 1ml 1M MgSO 4 , H 2 O to 1 liter). The cryovials were transferred to a -80oC freezer for two weeks. After two weeks, the worms were transferred to a petri dish with a lawn of E. coli OP50.
in the lid of the square dish, three drops of H 2 O d (4μl each one) were placed. On the other side of the square dish, in the area with value 6, the same drops (1μl each) of sodium azide 1M were placed; however, the only difference was that on the lid of the dish we put three drops of 1% benzaldehyde (1/100 diluted in H 2 O d ) (Supplementary Figure 1 of Remy and Hobert). 9
We used a platinum wire to select and pick up individual worms from a petri dish with E. coli OP50, transferred the worms to a petri dish without food, and held for 15 minutes. Then, 20 worms were transferred along the centerline of the square dish. The worms were counted every 15 minutes. At one hour, we had accumulated 80 values (each value designated the area where was the worms were in that moment), and we calculated a migration report, which Remy and Hobert 9 referred to as the Migration Index (MI).
The trained worms (worms imprinted with benzaldehyde) preferred areas 5 and 6 on the square petri dish, close to the benzaldehyde drops, and the untrained worms preferred areas 1 and 2, demonstrating a native attraction to the benzaldehyde (Figure 1). The mean of the MI was higher and very similar in all the studies with trained worms. The studies with untrained worms were also similar (Figure 1). The highest value of the MI was 4.23 and was obtained with trained and unvitrified worms and the lowest value was 1.34 in the untrained and not vitrified worms (Table 2). In general, the response of the trained worms to the benzaldehyde was double that of the untrained worms, whether they were cryopreserved or not. The variance of MI did not show homogeneity (Levene = 2.920, df1= 9, df2= 60, P=0.006) and the comparison of the media through one factor-ANOVA showed differences between groups (F=26.061, P=0.000). The Tahame test, for comparisons in pairs, showed differences between the two groups: trained and untrained worms, and no differences between the studies inside of each group (Supplementary Table 1). There were no differences between trained and vitrified worms and trained and not vitrified worms (Tahame, i-j=0.72, P=0.305). Also, there were no differences between untrained and slow freezing and trained and slow freezing (Tahame, i-j=0.24, p=0.138). Both methods of cryopreservation did not show differences in the MI average of trained worms and were also similar to the migration index of trained and worms that were not cryopreserved (Figure 1 and supplementary Table 1).
We demonstrated that cryoprotectants used in both the slow freezing and vitrification processes do not affect, alter, or change the mechanism that regulates the olfactory imprinting and long-term memory (Figure 1). Secondly, we determined that the process of cryopreservation methods of slow freezing or vitrification do not affect, alter, or change this mechanism (Figure 1). We also demonstrated that the results of the MI average obtained for the trained and untrained worms are similar to the results of the original authors of the odorant imprinting protocol. 9
The study shows the first results related to the persistence of memory after vitrification. Prior to this study, no other study or methodology had existed to carry out this project or a similar project."
#cryonics #transhumanism