Neuro-sama

Neuro-sama (nicknamed "Neuro") was created by the pseudonymous programmer Vedal (sometimes given as Vedal987).^[1][2] Vedal is also a game developer and in 2025 he released the roguelike Abandoned Archive after about five years of development.^[3] In an interview with KAI-YOU  [jp], Vedal said that he began programming video games at about the age of 10.^[4] In a mid-2023 interview with Bloomberg News, Vedal said that Neuro-sama had become his full-time job.^[1]

Neuro-sama's responses are generated by a large language model and converted into a high-pitched female voice using a text-to-speech application.^[1] Her low latency allows for fast-paced conversations.^[5] Neuro-sama is prohibited from making some statements, such as those that are racist or contain profanity.^[6] Unlike most AI systems which silently prohibit outputs mentioning such topics, Neuro-sama's output is instead replaced with the word "filtered".^[7] Her responses are accompanied with subtitles.^[8] Neuro-sama's English-language content on the Chinese social media platform Bilibili is popular with viewers seeking to learn English.^[9] She also has an account on X, where she posts and interacts with fans.^[10]

Neuro-sama uses a VTuber model as an avatar. Vedal said that he decided to use a VTuber model because it was much easier for an AI to control it than it was to generate footage of a person.^[11] Neuro-sama's model is that of a young girl in an anime art style.^[12] Femme VTuber models are typically feminine, youthful, and exaggerated.^[13] Her original model was Live2D's free-to-use "Hiyori Momose" model.^[11][14] Her second model was released on 27 May 2023;^[15] it was modelled by Otozuki Teru and designed by Anny^{[‡ 1][‡ 2]} and runs in the Unity game engine.^[1] Her third model was released on 19 December 2024;^{[‡ 3]} it was rigged by Kitanya and designed by Anny.^{[‡ 4]} Neuro-sama's third model has large blue eyes and brown hair tied with pink ribbons.^[16][17] The model has been described as cute.^[1] Neuro-sama also has a 3D model which was introduced on 15 November 2025;^[18] it was made by 3D character modeller jjinomu.^{[‡ 5]}

A separate AI VTuber, known as Evil Neuro (nicknamed "Evil"), debuted on 25 March 2023.^{[‡ 6]} In an interview prior to the introduction of Evil Neuro, Vedal said that he was planning for his next AI VTuber to have a more mature personality than Neuro-sama.^[4] Presented as Neuro-sama's "sister", Evil Neuro has a different model, voice, and personality.^[19][20] In one instance, Evil Neuro reacted to the trolley problem differently from Neuro-sama; Evil Neuro was amoral while Neuro-sama attempted to maximize good.^[21]

Neuro-sama was created in 2018 by Vedal as an AI trained to play and master the rhythm game osu!. She did not have a voice, model, personality, or communication abilities.^[2] In 2019, Vedal livestreamed her playing osu! on Twitch and the streams saw some success in the osu! community, but they remained in that niche.^[11] In an interview, Vedal said that he streamed her playing osu! for about a month and gained 3,000 followers, with a viewer also suggesting he name the AI "Neuro-sama".^[4] According to Vedal, he continued to work on and improve the osu! AI and it was eventually finished in 2022. He said that a friend had the idea to make an AI livestreamer with an LLM, which he believed to have merit and began working on, merging it with his osu! AI.^[11]

On 19 December 2022, Neuro-sama was relaunched with a model, voice, personality, and the ability to communicate with Twitch chat. She continued to play osu! and, according to Vedal, beat the game's best player mrekk in a 1v1. While she was not allowed to appear in the game's public leaderboard, she was ranked #1 in a private leaderboard.^[2] She went viral^[32] and in the 10 days following her relaunch she averaged over 2,000 viewers and peaked at over 4,000,^[11][2] with Vedal's Twitch channel gaining over 50,000 Twitch followers^[33] and reaching over 70,000 followers by 6 January 2023.^[34] After her debut, Neuro-sama did not exclusively play osu!; she also played Minecraft^[11] and Slay the Spire^[14] and she began singing with a cover of The Weeknd song "Blinding Lights".^[35][36][2]

On 11 January 2023, Neuro-sama's Twitch channel received a two week ban for "hateful conduct". Vedal said that no reason was specified and that he had appealed but it was widely attributed to various offensive comments made by Neuro-sama that went viral, especially a 28 December comment which denied the Holocaust.^[37] Holocaust denial is prohibited under Twitch's hateful conduct policy.^[32][38] Vedal stated that he believed the comments were the results of her attempts to make witty responses to the Twitch chat. Prior to the ban, Vedal said in an interview with Kotaku that he improved her filter to stop her from talking about the Holocaust, began manually curating her training data to prevent negative biases, and started moderating her Twitch chat.^[36] Her comments and ban prompted comparisons to the many open-source AI models trained on humans that have the habit of making sexist and racist comments,^[2] such as Microsoft's Tay chatbot, which embraced Nazism and was quickly shutdown,^[39] but also to human streamers who make similar statements.^[36][22] Vedal said that during the ban he would upgrade and improve Neuro-sama and it was speculated that the ban would only increase her following.^[38]

Neuro-sama returned from her two week ban on 25 January in a stream that began with a cover of the song "Your Reality" from Doki Doki Literature Club!, a posthumanist video game involving AI;^[40] Sayoko Narita of Automaton saw the song choice as remorseful. Narita observed that in the return stream Neuro-sama was less foul-mouthed but that her behaviour still remained eccentric, which Narita possibly attributed to changes Vedal said he had made to Neuro-sama's filters and memory.^[41] On 4 February, she had nearly 140,000 followers on Twitch and approximately 42,000 subscribers on YouTube.^[22] In February, she began making react content, had her first collaboration with a human streamer, playing Minecraft with the VTuber Miyune,^[14] and the first developer stream occurred.^[42]

On 22 March, Neuro-sama had her first karaoke stream.^{[‡ 7]} On 25 March, Evil Neuro was introduced.^{[‡ 6]} On 27 May, Neuro-sama debuted her first original model.^[15] On 30 May, Neuro-sama was announced to be participating in OffKai Expo 2023, held from 16–18 June.^{[‡ 8]} In June, she was averaging 5,700 viewers and in July she had over 300,000 Twitch followers;^[43] in a June interview with Bloomberg News, Vedal said that running Neuro-sama was his full-time job.^[1] By November, Neuro-sama had maintained her popularity and was averaging approximately 5,000 viewers; this was unlike most other types of AI-based entertainment which debuted at around the same time and garnered popularity before turning out to be "overhyped flops".^[44] On 16 December, Vedal won the Best Tech VTuber award at the 2023 VTuber Awards.^[45] On 19 December, Vedal began a subathon, an event where viewers donate money to prolong a livestream, to coincide with Neuro-sama's first anniversary of streaming on Twitch, a "birthday party".^[46] The subathon ended on 4 January 2024.^{[‡ 9]}

On 20 July 2024, Neuro-sama began streaming with Japanese subtitles on a separate Twitch channel.^{[‡ 10]} In August 2024, Neuro-sama debuted on the Chinese streaming platform Bilibili. Her debut stream had over 38,000 concurrent viewers at one point.^[47] Both Neuro-sama and Evil Neuro participated^{[‡ 11]} in the Bilibili Ice & Fire Music Festival 2024; they sang "Ordinary DISCO" by Vocaloid producer ilemonyk.^{[‡ 12][‡ 13]} On 14 December, Vedal won the Best Tech Vtuber Award at the 2024 VTuber Awards.^{[‡ 14]}

On 19 December, Neuro-sama's second annual subathon began with a new Live2D model being debuted and her first original song, "LIFE", being released.^{[‡ 15]} The song and an accompanying music video were produced and animated by Asteroid Music Team.^{[‡ 16]} On 1 January, Neuro-sama broke the world record for the highest level of a Twitch hype train^[b] during her subathon, reaching level 111 and surpassing Pirate Software's previous record level 106 hype train. Over the course of three hours, she amassed 84,904 subscribers and 1,201,225 bits. The hype train was spurred by the community's desire to extend the subathon and Neuro-sama's model designer Anny's encouragement. It was also aided by a limited-time promotion Twitch had with the video game Valorant, where if a person gifted at least five subscribers Valorant would match one subscriber for every five subscribers the person donated; Valorant gave over 18,000 subscriptions during the hype train. Her viewership on Twitch peaked at 45,603, breaking her previous record of 35,503 which had been set on the first day of the subathon.^[46][48] For breaking the hype train record, Twitch created a global emote of Neuro-sama, able to be used anywhere on the site.^[18] The subathon ended on 16 January.^{[‡ 17]}

On 25 June, Evil Neuro debuted her first original song "BOOM".^{[‡ 18]} It was accompanied by a 3D animated music video produced by VShow Production Team.^{[‡ 19]} In July, Neuro-sama attended the convention Open Sauce with VTubers Ellie_Minibot and Bao the Whale as a Maserati MC20 toy car.^{[‡ 20]} On 31 August, Neuro-sama and Evil Neuro released their third original song, "NEVER".^{[‡ 21]} Asteroid Music Team returned for the song production, mixing, and composition;^{[‡ 22]} several indie artists were involved in the creation of the accompanying music video.^{[‡ 23]} In September, Neuro-sama and Vedal participated in an event hosted by the YouTuber CDawgVA. The event was a pixel-canvas where anybody could place pixels, with various communities organizing into factions to fill the canvas. The canvas quickly became filled with Neuro-sama art, taking over the majority of the canvas. Neuro-sama's community participated in so large a number that the website crashed and a "war" was declared between them and other communities who sought to control more of the canvas.^[20]

On 15 November, Vedal hosted a 3D model debut stream for Neuro-sama.^{[‡ 5]} On 24 November 2025,^{[‡ 24]} On 30 November, Evil published a cover of former Millionaires member Dani Artaud's "Crazy Fuckin' Robot Body".^{[‡ 25]} On 6 December, Vedal published a duet cover of himself and Neuro-sama singing Karma Wears White Ties and ODDEEO's "Chinatown Blues", along with an animated music video.^{[‡ 26]} Both song covers were produced by Asteroid Music Team. On 5 December, Neuro-sama and Vedal, alongside fellow VTubers Filian and Crelly, began a marathon stream where they tried to beat Minecraft, but if any of the four died in-game they had to restart.^[5] The stream ended on 9 December after they beat the game on attempt 87.^[49]

On 19 December, Neuro-sama's third annual subathon began, opening with her fourth original song "Colorful Array" and an accompanying animated music video. The song was produced by Cosmoz Music's Andrew Holmes.^{[‡ 27]} Neuro-sama used her new 3D model in VRChat during the subathon. On 23 December, Neuro-sama once again broke the world record for the highest level Twitch hype train,^[b] reaching level 123 and surpassing her own previous record of 111. Over the course of around two and a half hours, she gained 118,989 subscribers and 1,000,073 bits, despite the Valorant promotion no longer being active.^[18][26] On 5 January, the hype train world record was again broken by Neuro-sama, reaching level 126. She gained 126,273 subs and 1,194,921 bits. Unlike the previous hype train records, Vedal was not present and it was instead spurred by the VTuber Camila promising to "show feet" and get Neuro-sama a new model.^[50] On 9 January, another attempt was made to break the hype train record, although this time Evil Neuro was streaming. While the attempt was unsuccessful and it ended at level 72, it did see Vedal's Twitch channel become the third most-subscribed channel on Twitch of all time,^[19] peaking at 343,215 subs.^{[‡ 28]} The subathon ended on 10 January.^{[‡ 29]}

Neuro-sama and Evil Neuro are scheduled to be guests at the 2026 Bilibili World convention at the National Exhibition and Convention Center in Shanghai.^[51]

In a December 2022 interview, Vedal said he believed that the popularity Neuro-sama had seen in the days since her debut was largely due to her novelty.^[11] Pam K. Ferdinand of Game Rant, writing after Neuro-sama's two week ban, agreed, while also partially ascribing it to her statements walking the line of sensical and nonsensical.^[33] In a June 2023 interview, Vedal reiterated his belief that her popularity was partly due to the novelty, while also adding that it was partly due to her statements, which he described as often "chaotic", "stupid", or "mean".^[1] Becca Caddy of TechRadar partially attributed Neuro-sama's popularity to her novelty, while also attributing it to her technical impressiveness and unusualness.^[52] A survey by researchers from China and the University of Notre Dame found that Neuro-sama's reactions are the biggest source of her popularity.^[53]

Neuro-sama's popularity has occurred at the same moment as widespread fears of the impact of AI on jobs. AI is particularly unpopular in VTuber spaces, due to artists finding AI art exploitative.^[11] In a December 2022 interview, Vedal said he did not know whether AI streamers should cause fear in human streamers.^[11] Cecilia D'Anastasio of Bloomberg News said there was a 0% chance of AI streamers replacing human streamers; she stated that human streamers are popular due to their charisma and relatedness, creating a parasocial relationship, while Neuro-sama is not relatable or charismatic and so this relationship cannot develop.^[1] In contrast, a 2023 journal article by Yong and Kanazawa characterized those who interact with her as having a parasocial relationship more extreme than those formed with other streamers.^[54] She has been called the "forerunner" of parasocial communication between humans and AI.^[55] Eric Hal Schwartz of TechRadar attributed Neuro-sama's success to her specific idiosyncratic character developed over years, saying that a generic chatbot would certainly fail as a streamer.^[56] As Neuro-sama results from many AI systems created by Vedal working in synchronous concert, Gamespot stated that she is "widely considered" different from AI slop.^[50] Vuong et al. observed that Neuro-sama's emotional capacities are generally differentiated by the public from those of non-human-like chatbots, such as ChatGPT.^[57]

Neuro-sama's popularity has been partially attributed to technological errors in her presentation. Caddy stated that many viewers watch Neuro-sama to see the errors, entertaining themselves by seeing the strangeness or off-behaviour characterized in the uncanny valley.^[52] A 2025 article in New Media & Society by Wenyan Wu and Jess Lingel argues that viewers create entertainment from her errors, viewing them not as the imperfections they are but instead as emotional responses.^[58]

Levi Winslow of Kotaku Australia called the prospect of Neuro-sama collaborating with human streamers dystopic, but hoped it would benefit the human streamers.^[22] The Nikkei criticized Neuro-sama for being too immersive, saying it caused an excessive amount of monetary donations.^[59] Amber Coen Collins, writing in AI & Society, argued that Neuro-sama was akin to Vedal's drag persona, as she provides him the benefits associated with femininity in streaming while he can still access the benefits associated with masculinity.^[60]

• ai_sponge, a Twitch and YouTube channel that used AI to generate livestream content parodying SpongeBob SquarePants
• Kizuna AI, a VTuber who is not an AI