Neuroscientists at Oxford just discovered how your brain moves memories into long-term storage. It’s called an anti-memory, and it’s more helpful than it sounds.
Memories, at their most basic, are electrical impulses. But what happens if those impulses are always firing? Would they overload your brain the same way that running too many programs on your computer would fry its RAM? The answer is yes. Scientists think that these overly excited neurons could be the culprits behind conditions like epilepsy, schizophrenia, and autism. The balancing agent that keeps that from happening are anti-memories.
Think of them as defragging a memory’s RAM. Anti-memories are neurons that lower the electrical activity generated by memory creation. Anti-memories work together with memories to keep the brain from getting overloaded. They don’t affect memories; they just silence the process running them so your brain can do other things.
When you form a memory, your brain assembles it from different parts of your brain, rebuilding it each time from scratch. There are three steps to building a memory — encoding it (intentionally committing it to memory), consolidating it (different parts of the brain acting gluing the memory together) and retrieving it (recalling the memory). Every time you retrieve a memory, you increase your brain’s ability to recall it by strengthening the neural pathway to that memory. That makes the memory stronger and easier to recall in the long run. Here’s a quick primer:Credit: Head Squeeze, Brit Lab/YouTube
Anti-memories work in the same way, just in reverse. Scientists had long theorized their existence from models and studies on mice. Neurologists at the University of Oxford were finally able to observe them in humans with this experiment, whose findings were published in the journal Neuron. Lead author Helen Barron explains the process in a press release:
To measure these links, or associative memories, we use a technique called repetition suppression where repeated exposure to a stimulus – the shapes in this case – causes decreasing activity in the area of the brain that represents shapes. By looking at these suppression effects across different stimuli we can use this approach to identify where memories are stored.
The memory paths identified in the study. Credit: Neuron
The researchers were able to do this by observing participants’ brain activity as they memorized the shapes using functional magnetic resonance imaging (fMRI). Over time, the anti-memory neurons kicked in and blocked the memories of the shapes. “Over 24 hours, the shape associations in the brain became silent,” said Barron. Most interestingly, they didn’t look like additional memories; they looked like an absence of brain activity. They’re not – they’re just active on the same neural path. Think of it as someone retracing their steps, like this:
“The Shining” via GIPHY
That could have been because the brain was rebalanced or it could simply be that the associations were forgotten. The following day, some of the volunteers undertook additional tests to confirm that the silencing was a consequence of rebalancing. If the memories were present but silenced by inhibitory replicas, we thought that it should be possible to re-express the memories by suppressing inhibitory activity.
In order to re-express the memories, researchers used transcranial direct current stimulation (tDCS) to apply a low current of electricity to the volunteers’ brains. By doing this, the researchers reduced the activity of the anti-memory neurons — and the memories of the shape associations came back.
“This result is consistent with a balancing mechanism,” Barron says. “The increase in excitation seen in learning and memory formation, when excitatory connections are strengthened, appears to be balanced out by a strengthening of inhibitory connections.”
While the sample size for this study was small, the research team has big hopes for their findings. “The paradigm has the potential to be translated directly into patient populations, including those suffering from schizophrenia and autism,” said Barron. “We hope that this research can now be taken forward in collaboration with psychiatrists and patient populations so that we can develop and apply this new understanding to the diagnosis and treatment of mental disorders.”
So do we.
Wataalamu wa neva wa Oxford wamegundua jinsi ubongo unavyohifadhi kumbukumbu kwa muda mrefu. Inaitwa anti-kumbukumbu, na ni muhimu zaidi kuliko inavyoonekana. Kumbukumbu, kwa msingi wao, ni msukumo wa umeme. Lakini nini kinatokea ikiwa mienendo hiyo huchochea daima? Je, akili yako itafadhaika kwa sababu ya kutumia programu nyingi kupita kiasi? Jibu ni ndiyo. Wanasayansi wanafikiri kwamba chembe hizo za neva zilizoamsha kupita kiasi zinaweza kusababisha magonjwa kama vile kifafa, ugonjwa wa akili, na ugonjwa wa akili. Kichocheo cha kusawazisha ambacho huzuia hilo lisitokee ni kumbukumbu-kinyume. Fikiria yao kama defragging kumbukumbu ya RAM. Anti-makumbusho ni neuroni ambazo hupunguza utendaji wa umeme unaotokana na uundaji wa kumbukumbu. Vipengele vya kukumbuka vinafanya kazi pamoja na kumbukumbu ili kuzuia ubongo usichukuliwe sana. Hazihusishi kumbukumbu; zinafanya tu mchakato unaozitumia usiweze kufanya kazi ili ubongo wako uweze kufanya mambo mengine. Wakati kumbukumbu inapoundwa, ubongo huunganisha kumbukumbu kutoka sehemu tofauti za ubongo na kuijenga upya kila wakati. Kuna hatua tatu za kujenga kumbukumbu - kuifunga (kuiweka kimakusudi katika kumbukumbu), kuifanya imara (sehemu tofauti za ubongo zinafanya kazi ya kushikamana na kumbukumbu) na kuipata (kukumbuka kumbukumbu). Kila mara unapopata kumbukumbu, unaongeza uwezo wa ubongo wako kuikumbuka kwa kuimarisha njia ya neva ya kumbukumbu hiyo. Hilo hufanya kumbukumbu iwe na nguvu zaidi na iwe rahisi kukumbuka kwa muda mrefu. Hapa ni primer haraka: Mikopo: Kichwa Squeeze, Brit Lab / YouTube Anti-makumbusho kazi kwa njia ile ile, tu kinyume. Kwa muda mrefu wanasayansi walikuwa wamedokeza kwamba zipo kwa sababu ya mifano na masomo yaliyofanywa juu ya panya. Wataalamu wa neva wa Chuo Kikuu cha Oxford waliweza kugundua dalili hizo katika binadamu kwa majaribio yao, na matokeo ya majaribio hayo yalichapishwa katika jarida la Neuroscience. "Helen Barron, mwandishi mkuu wa utafiti huo, alielezea mchakato huu katika taarifa ya vyombo vya habari: ""Kupima viungo hivi, au kumbukumbu za ushirika, tunatumia mbinu inayoitwa kukandamiza kurudia ambapo kufunuliwa mara kwa mara kwa kichocheo - maumbo katika kesi hii - husababisha kupungua kwa shughuli katika eneo la ubongo linalowakilisha maumbo." Kwa kuangalia athari hizi za kukandamiza katika vichocheo tofauti tunaweza kutumia mbinu hii kutambua ambapo kumbukumbu zimehifadhiwa. Njia za kumbukumbu zilizotambuliwa katika utafiti huo. Watafiti waliweza kufanya hivyo kwa kuchunguza shughuli za ubongo wa washiriki walipokuwa wakikumbuka maumbo kwa kutumia upigaji picha wa sumaku (fMRI). Baada ya muda, chembe za neva za kupambana na kumbukumbu zilianza kufanya kazi na kuzuia kumbukumbu za maumbo hayo. "Kwa zaidi ya masaa 24, ushirika wa umbo katika ubongo ulikaa kimya, ""alisema Barron." Jambo la kupendeza zaidi ni kwamba hazikuonekana kama kumbukumbu za ziada; zilionekana kama kutokuwa na utendaji wa ubongo. Wao si <unk> wao ni tu hai juu ya njia hiyo hiyo ya neva. "Kama mtu akirudia hatua zake, kama hii: ""The Shining"" kupitia GIPHY Hiyo inaweza kuwa kwa sababu ubongo ulirudishwa usawa au inaweza kuwa tu kwamba ushirika ulisahauliwa." Siku iliyofuata, baadhi ya wajitoleaji walifanya vipimo vya ziada ili kuthibitisha kwamba ukimya ulikuwa matokeo ya kusawazisha. Kama kumbukumbu zilikuwapo lakini zilinyamazishwa na replicas inhibitory, tulidhani kwamba ni lazima iwezekanavyo kuelezea tena kumbukumbu kwa kukandamiza shughuli inhibitory. Ili kuimarisha kumbukumbu, watafiti walitumia Transcranial Direct Current Stimulation (TDCS) kutumia umeme mdogo kwenye ubongo wa wajitoleaji. Kwa kufanya hivyo, watafiti walipunguza shughuli za neuroni za kupambana na kumbukumbu <unk> na kumbukumbu za ushirika wa umbo zilirudi. "Mafunzo haya ni sawa na utaratibu wa kusawazisha", anasema Barron. "Kuongezeka kwa msisimko unaoonekana katika kujifunza na muundo wa kumbukumbu, wakati uhusiano wa msisimko unaimarishwa, unaonekana kusawazishwa na kuimarisha uhusiano wa kuzuia. ""Wakati ukubwa wa sampuli ya utafiti huu ulikuwa mdogo, timu ya utafiti ina matumaini makubwa kwa matokeo yao." "Mfano huo una uwezo wa kutafsiriwa moja kwa moja kwa idadi ya wagonjwa, ikiwa ni pamoja na wale wanaoteseka na schizophrenia na autism", alisema Barron. "Tunatarajia kwamba utafiti huu sasa unaweza kuchukuliwa mbele kwa kushirikiana na wagonjwa wa akili na idadi ya wagonjwa ili tuweze kuendeleza na kutumia uelewa huu mpya kwa utambuzi na matibabu ya matatizo ya akili. """