Neuroimaging, Cannabis, uye Brain Performance & Basa

"I think poto inofanirwa kunge iri pamutemo. Ini handisi kuiputa, asi ndinoda hwema hwayo." -Andy Warhol

Cannabis ine mamorekuru akasiyana siyana anosunga kune anogamuchira muuropi, zvinodaidzwa kunzi "cannabinoid receptors." Inozivikanwa ligands (inosunga kune avo vanogamuchira) inosanganisira THC (tetrahydrocannabinol) uye CBD (cannabidiol), inosunga kune zvinogashira senge CB1 uye CB2 zvinogamuchirwa zvine akasiyana siyana ekudzika mabasa pauropi.

Iyo yekutanga neurotransmitter inobatanidzwa mukuzvarwa (endogenous) cannabinoid chiitiko "anandamide," yakasarudzika "fatty acid neurotransmitter" rine zita rinoreva "mufaro," "mufaro," kana "kufadza" muSanskrit uye inowirirana mitauro yekare. Iyi neurotransmitter system yangove ichangobva kuongororwa zvakadzama, uye iyo yekutanga biology yakanyatsogadziriswa (semuenzaniso, Kovacovic & Somanathan, 2014), kugadzirisa kunzwisiswa kwekurapa, kwekuvaraidza, uye kwakashata mhedzisiro yezvakasiyana cannabinoids, uye kugadzira nzira yenhau yekugadzira mishonga yekuvandudza.

Kuwedzera kwekuda kwekurapa uye kwekuvaraidza kushandiswa kwecannabis kunoda kunzwisiswa kukuru kwemhedzisiro ye cannabis pauropi uye maitiro. Nekuda kwekupokana uye kuita zvematongerwo enyika zvembanje muhurukuro yemagariro, dzidziso dzakasimba pamusoro pecannabis dzinotitadzisa kugona kutaurirana zvine hungwaru nezvakanaka zvekushandisa kwecannabis uye zvakatadzisa zvirongwa zvekutsvagisa. Zvakangodaro, nyika zhinji dzakabvumidza kushandiswa kwekurapa uye kwekuvaraidza kwekugadzirira kwecannabis, nepo hurumende yemubatanidzwa iri kudzokera kumashure kune mamwe marongero anodzvanyirira.

Dare redzimhosva rinobuda

Vanotsigira kannabis, kune rumwe rutivi, vanogona kupenda zvakare zvakapusa mufananidzo wezvakanakira kugadzirira kannabis, kudzikisira kana kurasa ruzivo rwakakodzera pamusoro penjodzi dzecannabis mune vamwe vanhu vari panjodzi yekumwe kunetseka kwepfungwa, njodzi dzekushungurudzwa kwekushandisa cannabis, uye zvakashata zvinokonzerwa necannabis pane mamwe maitiro ekuziva anoperekedzwa neanogona kukanganisa, uye kunyange ane njodzi, mhedzisiro pakutora sarudzo uye maitiro.

Semuenzaniso, nepo gadziriro dzekannabis dzakaratidzirwa kuve dzinobatsira pakurapa kwekurwadziwa uye nekuvandudza mashandiro mumamiriro akasiyana siyana, kuvandudza hupenyu, cannabis inogona kukonzera kukanganisa mukutonga uye kunonoka mukugadzirisa ruzivo, izvo zvinogona kutungamira kwete chete kumatambudziko emunhu, asi inogona kupinda munzira yehukama uye zviitiko zvehunyanzvi, zvichitungamira mukukuvadza kune vamwe nekupa tsaona.

Cannabis yave ichibatanidzwa zvakajeka nekukonzeresa kutanga uye kuwedzera zvimwe zvirwere, kunyanya mamiriro epfungwa. Zvakare, pane kufarira kuri kukura pakunzwisisa kugona kwekurapa uye kwehutachiona hweakasiyana makemikari ari mukati mekugadzirira kwecannabis, kunyanya THC neCBD- kunyangwe kukosha kwezvimwe zvinhu kuri kuwedzera kuzivikanwa. Semuenzaniso, ongororo ichangoburwa muAmerican Journal of Psychiatry inoratidza zvakasimba kuti CBD, inobatsira pakurapa kusagadzikana kusingaite (semuenzaniso, Rosenberg et al., 2015), inogona kubatsira zvakanyanya sekuwedzera mumiririri kune vamwe vane schizophrenia (McGuire at al ., 2017).

Mufananidzo wacho hausi-kana, zvakadaro. Kunzwisisa kwakadzama kwekuti cannabis inokanganisa sei nzvimbo dzakasiyana dzehuropi (pasi pemamiriro akasiyana, semuenzaniso, zvakanyanya vs. kushandiswa kusingaperi, pamwe uye pasina akasiyana hutano hwepfungwa uye kusagadzikana kwekushandisa zvinodhaka, nekusiyana kwemunhu, nezvimwewo) kunodiwa kumisikidza gakava mune ruzivo, uye inopa yakasimba, yakavimbika yesainzi zvakawanikwa kugadzira nzira yekutsvagurudza mune ramangwana. Kunzwisisa kwekutanga kuri kushomeka, uye nepo paine boka rekuwedzera rekutsvaga rinotarisa kwakasiyana-siyana kwecannabis mhedzisiro, sezvazvinogara zvichiitika neboka rekutsvagisa rinotanga, nzira yacho yakasiyana siyana muzvidzidzo zvidiki, pasina hwaro hwakajeka kukurudzira nzira dzisingachinji dzekuongorora.

Mumwe mubvunzo wekukosha kuri pachena ndewokuti: Ndeipi mhedzisiro ye cannabis pane akakosha anoshanda nzvimbo dzehuropi? Iko kushanda uye kubatana kunoshanduka sei mukati meakakosha maatomic matunhu ("hubs," mune network dzidziso) inopararira kune maratidziro ehuropi ayo ari pakati? Cannabis inoshandisa sei, kusvika padanho ratinonzwisisa mhedzisiro yaro, kutamba pane mamwe mabasa anoshandiswa kudzidza kugona? Ndezvipi, kazhinji, mhedzisiro yehunabis pamambure ehuropi, kusanganisira iyo default mode, manejimendi kutonga, uye masisitiri network (matatu akakosha maneti mune yakabatana zvakanyanya "kirabhu yakapfuma" yehuropi network)?

Iyi uye mimwe mibvunzo yakabatana yakanyanya kukosha apo patinosvika pakunzwisisa zvirinani kuti gakava repfungwa / rehuropi rinogadziriswa sei nekufambira mberi mukugadzira mepu dzevanhu. Izvo zvinotarisirwa ndezvekuti zvinowedzera kana kudzikira muchiitiko munzvimbo dzakasiyana dzehuropi muvashandisi (zvichienzaniswa nevasiri vashandisi) zvinowirirana neshanduko dzakakura pamatanho ehuropi anoshanda, ayo anoratidzwa mumatanho ekusiyana kwekuita paboka rakakura reanowanzoshandiswa maturusi ekutsvaga kwepfungwa. iyo inobata akasiyana maitiro epfungwa mashandiro uye hunhu hwevanhu.

Chidzidzo chezvino

Neichi chakakosha kutarisisa mupfungwa, boka revanotsvaga (Yanes et al., 2018) rakatanga kuunganidza uye kuongorora ese akakodzera neuroimaging mabhuku anotarisa mhedzisiro ye cannabis pauropi uye pamaitiro uye psychology.

Izvo zvakakosha kuti uongorore iyo meta-analytic nzira yakashandiswa muchidimbu uye kukurukura kuti ndedzipi mhando dzedzidzo dzakabatanidzwa uye dzakasiyiwa, kuitira kuti mamiriro uye kududzira zvakanyanyisa kukosha zvakawanikwa. Vakatarisa mabhuku anosanganisira zvidzidzo vachishandisa fMRI (inoshanda magnetic resonance imaging) uye PET scans (positron emission tomography), zvakajairika maturusi ekuyera zviratidzo zvehuropi chiitiko, uye vakaita maviri ekutanga ongororo kuronga iyo data.

Chekutanga, vakapatsanura zvidzidzo izvi kuita uko zviitiko munzvimbo dzakasiyana dzehuropi zvaigona kuwedzerwa kana kuderera kune vashandisi maringe nevasiri vashandisi uye zvakaenzana nzvimbo dzeatomic nehurongwa hunoshanda hwehuropi hwavari zvikamu. Muchikamu chechipiri chekunatsiridza, ivo vakashandisa "inoshanda kududzira" kuti vaone nekuisa mumapoka akasiyana emapoka epfungwa anoyerwa pamabhuku aripo.

Semuenzaniso, zvidzidzo zvinotarisa pane yakakura asi dzakasiyana seti yemabasa epfungwa kuti uone kuti, kana zviripo, cannabis inoshandura sei kugadzirisa uye kugadzirisa kwepfungwa. Anoshanda mabasa aisanganisira kutora danho, kukanganisa kukanganisa, kugadzirisa gakava, kukanganisa mutemo, mubairo uye zvinokurudzira mabasa, kutonga kwekumanikidza, mabasa epamusoro, uye ndangariro, kupa runyorwa rusina kukwana. Nekuti zvidzidzo zvakasiyana zvakashandisa ongororo dzakasiyana pasi pemamiriro akasiyana, kugadzira nzira yakaunganidzwa yekuongorora yakakosha kuitisa ongororo yakazara uye kuongorora.

Kutsvaga akawanda akaenzana dhatabhesi, ivo vakasarudza zvidzidzo zvine imaging vachienzanisa vashandisi nevasiri vashandisi, nedata rinowanikwa muchimiro chemienzaniso mienzaniso inokodzera kuongororwa kwakabatanidzwa, uye izvo zvaisanganisira kuyedzwa kwepfungwa kwekuona, kufamba, manzwiro, kufunga, uye kugadzirisa ruzivo rwevanhu, mumubatanidzwa wakasiyana siyana. Vakabvisa avo vane hutano hwepfungwa, uye zvidzidzo zvichitarisa mhedzisiro yekushandisa cannabis. Ivo vakaongorora iyi yakamisikidzwa data.

Tichitarisa iko kutendeuka mukutsvaga kweiyouroimaging pane zvese zvidzidzo uchishandisa ALE (Activation Likelihood Estimate, iyo inoshandura iyo data kuenda kune yakajairwa mepu mepu modhi), vakaona kuti ndeapi matunhu anga achinyanya kushanda. Vachishandisa MACM (Meta-Analytic Kubatanidza Modeling, iyo inoshandisa iyo BrainMap dhatabhesi yekuita yakazara-yehuropi yekumisikidza mapatani), ivo vakaona masumbu ematunhu ehuropi ayo akamisidzana pamwechete.

Vakapedzisa chikamu chinoshanda chekumisikidza nekutarisa kumberi uye kudzosera kumashure maitiro ekudzokorora kubatanidza chiitiko chehuropi pamwe nekushanda kwepfungwa, uye kushanda kwepfungwa nebasa rehuropi, kuti unzwisise maitiro akasiyana epfungwa anoenderana nemabasa munzvimbo dzakasiyana dzehuropi.

Heino pfupiso yeiyo yakazara meta-analytic "pombi":

Zviwanikwa

Yanes, Riedel, Ray, Kirkland, Shiri, Boeving, Reid, Gonazlez, Robinson, Laird, uye Sutherland (2018) akaongorora huwandu hwedzidzo makumi matatu neshanu. Zvese zvakataurwa, paive nemakumi masere nemasere ezvinhu-ane basa, iine zvinhu makumi maviri nezviviri zvine chekuita nekudzikira kwekusimudzira pakati pevashandisi vecannabis ne472 nevasiri vashandisi, uye zvikamu zana negumi nematanhatu zvine chekuita nekuwedzera kushanda pakati pevashandisi ve482 uye 434 vasiri vashandisi. Paive nenzvimbo nhatu huru dzekutsvaga:

Paive nenzvimbo dzinoverengeka dzeshanduko dzinochinja ("convergent") dzakacherechedzwa pakati pevashandisi nevasiri vashandisi, maererano nekumisikidza uye kusagadzikana. Kuderera kwakatariswa mukati memaviri (mativi ese ehuropi) ACCs (anterior cingulate cortex) uye kurudyi DLPFC (dorsolateral prefrontal cortex). Nekupesana, kwaive nekuwedzera kwekushandurwa kwakagara kuchionekwa mune chaiyo striatum (uye ichienderera kune kurudyi insula). Izvo zvakakosha kuti uzive kuti izvi zvakawanikwa zvaive zvakasiyana kubva kune mumwe nemumwe, uye kushomeka kwekuyanana zvinoreva kuti zvinomiririra zvakasarudzika zvakasiyana mhedzisiro ye cannabis pane akasiyana masisitimu.

MACM ongororo yakaratidza kuti paive nemasumbu matatu eakagovaniswa huropi matunhu:

• Cluster 1 - ACC yaisanganisira yakazara-yehuropi yekumisikidza mapatani, kusanganisira kubatana neiyo insular uye caudate cortex, medial frontal cortex, precuneus, fusiform gyrus, culmen, thalamus, uye cingate cortex. Iyo ACC kiyi yekutora sarudzo uye kugadzirisa gakava uye inosanganisirwa nekuongorora nekuzvipira kune yakapihwa nzira yekuita (semuenzaniso, Kolling et al., 2016), uye idzi nzvimbo dzinoenderana dzinovhara huwandu hwakawanda hwemabasa ane hukama neAAC. Iyo insula inosanganisirwa nekuzviona-kwavo, muenzaniso unozivikanwa kuve chiitiko chekuona kwekuzvinyangadza.
• Cluster 2 - DLPFC yaisanganisira co-activation pamwe neparietal matunhu, orbitofrontal cortex, occipital cortex, uye fusiform gyrus. Sezvo DLPFC ichibatanidzwa nemabasa akakosha ehutungamiriri, kusanganisira kudzora manzwiro, ruzivo rwekunzwa, uye kutungamira kwezvekucherechedza zviwanikwa (semuenzaniso, Mondino pa al., 2015) pamwe nezvikamu zvekugadzirisa mutauro, nenzvimbo dzakanangana nekero mabasa akakosha, kusanganisira kugadziriswa kweruzivo rwemagariro, kutonga kwekushushikana, uye zvine hukama.
• Cluster 3 - Striatum yaisanganisira yakazara-huropi kubatanidzwa, kunyanya iyo insular cortex, kumberi cortex, yepamusoro parietal lobule, fusiform gyrus, uye culmen. Iyo striatum inosanganisirwa nemubairo-iyo inonzi "dopamine hit" inotsanangurwa kazhinji-iyo iyo kana yakanyatsogadziriswa inotibvumidza kuteedzera kwakanyanya kubudirira, asi mumatunhu ekusaita-chiitiko kunotungamira mukusaita basa, uye mukuwedzera kunopa kune ekurwisa uye ekumanikidza maitiro . Humbowo hwakadzokororwa mupepa rekutanga hunoratidza kuti kushandiswa kwecannabis kunogona kupa mubayiro maseketi kutungamira kupindwa muropa, uye pamwe nekukurudzira kwakashata kwezviitiko zvakajairika.

Nepo masumbu aya achishanda zvakasiyana maererano nemabatirwo avanoitwa necannabis, anopindirana nenzira uye nepakati, zvichiratidza kukosha kwakakosha kwekutarisa zviitiko zvehuropi kubva kuchikamu chekubatanidza, chakabatanidzwa kuitira kuti vanzwisise kududzirwa kwehuropi hunodzora hunowanikwa sei pfungwa dzinoshanda, uye kuti izvi zvinotamba sei kune vanhu muhupenyu hwezuva nezuva.

Kugadziriswa kwekushanda kwemasumbu matatu kwakaratidza maratidziro anoita kuti sumbu rimwe nerimwe riwirirane neboka rekuyedzwa kwepfungwa. taura mashoma. Ini handisi kuzozviongorora zvese, asi zvakawanikwa zvakakosha, uye zvimwe zvacho zvinomira (ona pazasi).

Uku kutarisisa kwehukama-basa hukama hunobatsira. Kunyanya kucherechedzwa kuvepo kweye go / no-go basa mamiriro munzvimbo dzese nhatu dzinoshanda:

Kuenderera mberi kwekufunga

Takatorwa pamwe chete, mhedzisiro yeiyi meta-ongororo yakadzama uye inozadzisa zvinangwa zvekutarisa mukati nekudzikisa zvakawanikwa pane ese akakodzera mabhuku achiongorora mhedzisiro yekushandisa kannabis muhuropi hwekuita muvanhu vasina chirwere chepfungwa, vachitarisa kuwedzera uye kudzikira kwezviitiko munzvimbo nzvimbo dzehuropi, dzakaparadzirwa masumbu ehukosha hwakasarudzika, uye kukanganisa kune akakosha epfungwa ekugadzirisa mabasa uye basa.

Cannabis inoderedza chiitiko mune ese maACC uye DLPFC masumbu, uye kune vanhu vane zvakajairika huropi hunoshanda, izvi zvinogona kutungamira kumatambudziko mukuita kwekuita uye kuita sarudzo. Cannabis ingangokonzeresa kusarongeka mukutarisa kwekukanganisa, zvichitungamira mukufungidzira uye nenyaya dzekuita nekuda kwekukanganisa, uye zvinogona kukanganisa mashandiro panguva yemakakatanwa ezvinhu, kubva pazvikanganiso zvese mukutonga pamwe nekuchinja kwesarudzo uye kuuraya kunotevera. Kuderera kwechiitiko cheDLPFC kunogona kutungamira kumatambudziko ekudzora emweya, pamwe nekuderera kwekurangarira uye kudzora kwekutarisa.

Kune vanhu vane chirwere chepfungwa uye chekurapa, mhedzisiro yeuropi inogona kunge iri yekurapa, semuenzaniso kudzikisa marwadzo nekudzora chiitiko cheACC, kudzikamisa ndangariro dzinoshungurudza nekudzvinyirira hope dzinotambudza, kurapa kushushikana nemhedzisiro, kana kudzora zviratidzo zvepfungwa (McGuire, 2017) nekudzivisa chiitiko munzvimbo dzine huropi.

Asi cannabinoids zvakare inogona kukonzeresa hutachiona, kudzikisira kushushikana kana psychosis, uye mamwe mamiriro, mune vanhu vanotambura. Kushandiswa kweCannabis kunokonzeresa matambudziko ehuropi huri kukura, zvichitungamira kune zvisingadiwe mhedzisiro yenguva refu (semuenzaniso, Jacobus naTappert, 2014), senge kudzikiswa kwekusaziva kwekuita uye shanduko yesimba muuropi.

Cannabis yakaratidzirwa, mukupesana, kuwedzera chiitiko mu striatum nenzvimbo dzakabatana kazhinji. Kune vanhu vane zvakajairwa zvekutanga zviitiko, izvi zvinogona kutungamira mukutanga kwemubairo maseketi, uye sezvakaonekwa muzvidzidzo zvakawanda, zvinogona kuwedzera njodzi yekuita muropa nekumanikidza maitiro, zvichitungamira kune mamwe marudzi ehurwere. Uku kusimudzira kwemubairo chiitiko (chakabatanidzwa nemhedzisiro kumasumbu maviri ekutanga) kunogona kupa "kukwirisa" kwembanje kudhakwa, kusimudzira kunakidzwa uye basa rekugadzira, zvichiita kuti zvese zviwedzere uye zviite, kwechinguva.

Vanyori vanocherekedza kuti masumbu ese matatu aisanganisira iyo go / no-go basa, bvunzo mamiriro inoda kudziviswa kana kuita kwechiitiko chemotokari. Ivo vanoona:

"Pano, iyo chokwadi chekuti dunhu rakasarudzika-rakanangana nekukanganiswa raive rakabatana neyakafanana basa kupatsanurwa kunogona kunge kuri kuratidza kwehunhu-hwakabatana mukomputa mhedzisiro inoratidzwa pazvidzidzo zvese. chiitiko chekutanga (ACC neDL-PFC) uye kukwidziridzwa kwezviitiko zvinouraya. "

Kune vamwe varwere, cannabis inonzi inoderedza zviratidzo zvekushushikana, zvinoratidzirwa nezviitiko zvepakati zvekurasikirwa nemufaro, zvakanyanya kusagadzikana manzwiro, uye kushomeka kwekukurudzira, pakati pezvimwe zviratidzo, asi vashandisi vanorema vari panjodzi yekuwedzera kushungurudzika (Manrique-Garcia et al. ., 2012).

Nekudaro, mukuwedzera kune zvingangodaro zvinokonzeresa kupindwa muropa nemamwe makemikari uye kusimudzira zviitiko zveavo vanofarira kudhakwa nembanje (vamwe vanoiona ichiburitsa dysphoria, kushushikana, kusagadzikana kusingafadzi, kana kunyange paranoia), vashandisi vanogona kuona kuti mukushayikwa kwekushandisa kwecannabis , ivo havanyanyo kufarira zviitiko zvenguva dzose kana zvisina kukwirira, zvichitungamira kudzikira kwekunakidzwa uye kurudziro.

Iyi mhedzisiro yakasiyanasiyana zvichienderana nezvakawanda zvinoenderana nekushandiswa kwecannabis, senge nguva uye kusagadzikana kwekushandisa, pamwe nerudzi rwecannabis uye nehukama kemesitiri, yakapihwa misiyano pakati pemarudzi akasiyana siyana nematambudziko. Nepo kudzidza uku kusingakwanise kusiyanisa pakati pemhedzisiro yeTHC neCBDD, sezvo data raive risingawanikwe pakumisikidzwa kana kuenzana kwezvinhu zviviri izvi zvakakosha mu cannabis, zvingangove kuti zvine mhedzisiro dzakasiyana pahuropi basa iro rinoda kumwe kuongorora kunze kwekurapa kugona kubva mukuvaraidza uye pathological mhedzisiro.

Ichi chidzidzo kudzidza kwakavakirwa, kumisikidza danho rekuenderera mberi nekutsvaga pamusoro pemhedzisiro yeakasiyana cannabinoids pahuropi muhutano uye kurwara, uye kupa data rakakosha kuti unzwisise kurapa uye kukuvadza mhedzisiro yeakasiyana cannabinoids. Iyo yakashongedzwa uye inorwadza nzira mune ino fundo inopenya ratidziro yekuti cannabis inokanganisa sei huropi, ichipa rakakosha dhata nezve zvese zvinokanganisa maratidziro ehuropi pamwe nekuziva uye nemanzwiro basa.

Mibvunzo yekufarira inosanganisira iyo yekuwedzera mepu yehuropi network uye kuenzanisa izvi zvakawanikwa nemhando dziripo dzepfungwa, kutarisa mhedzisiro yemhando dzakasiyana dzecannabis uye mapatani ekushandisa, uye kuongorora mhedzisiro ye cannabinoids (zvinowanzoitika-zvinowanzoitika, zvisingagumi, uye synthetic ) yezvinangwa zvekurapa mumamiriro akasiyana emakiriniki, kushandiswa kwekuvaraidza, uye zvingangoita ekuvandudza mashandiro.

Chekupedzisira, nekupa hwaro hwakabatana hwekunzwisisa zvinyorwa zviripo zvinosanganisira zvakanaka uye zvakaipa zvinokonzerwa necannab pauropi, bepa rino rinotsvagisa kanabis zvakanyanya munzvimbo yepakati yekudzidza kwesainzi, ichipa iyo yekusarerekera, de-stigmatized chikuva kubvumidza gakava pane cannabis kuti ishanduke munzira dzinovaka kupfuura zvayakaita kare.

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