Editing Circadian half-cycler

{{Royalty}}{{infobox main|
| name = Circadian half-cycler
| image = Health item bionic.png|Circadian half-cycler
| type = Medical Items
| type2 = Body Parts
| tech level = Spacer
| description = A signal redirector which isolates half of the brain, allowing the other half to sleep while the user remains outwardly awake. By alternating brain halves, the user never needs to sleep. Unfortunately, two hemispheres are better than one - working half a brain causes a reduction in consciousness.
| production facility 1 = Fabrication bench
| research = Circadian influence
| skill 1 = Crafting
| skill 1 level = 8
| resource 1 = Plasteel
| resource 1 amount = 15
| resource 2 = Advanced component
| resource 2 amount = 4
| work to make = 26000
| mass base = 4
| hp = 50
| flammability = 1.0
| thingSetMakerTags = RewardStandardLowFreq
| tradeTags = Bionic, ImplantEmpireCommon
| techHediffsTags = Advanced, ImplantEmpireCommon
}}
The '''circadian half-cycler''' is an [[artificial body part]] that removes a pawns need to sleep at the cost of a permanent 15% [[Consciousness]] penalty.

== Acquisition ==
Circadian half-cyclers can be crafted at a [[{{P|Production Facility 1}}]] once the [[Research#{{P|Required Research}}|{{P|Required Research}}]] research project has been completed. The required [[techprint]] can be obtained either by [[trade]] or completing [[quests]] for the [[Empire]]. They require {{Required Resources}}, {{Ticks|{{P|Work To Make}}}} of work, and a [[{{P|Skill 1}}]] skill of {{P|Skill 1 Level}}.

== Summary ==
A circadian half-cycler is installed in the brain and removes the [[Sleep]] need entirely. [[Consciousness]] is reduced by 15%, which itself reduces work-related stats like [[Moving]] and [[Manipulation]], as well as [[Eating]] and [[Talking]].

When a pawn with this implant is shocked with [[EMP]], they will receive [[brain shock]], knocking them unconscious temporarily.

=== Installation ===
Installing the part requires {{Ticks|2500}} of work, 2x medicine of [[Herbal medicine|herbal]] quality or better, and a [[Skills#Medical|Medical skill]] of 5.

Removing the part requires {{Ticks|2500}} of work, 1x medicine of [[Herbal medicine|herbal]] quality or better, and a [[Skills#Medical|Medical skill]] of 5.

If the operation fails, the part will be destroyed.

== Analysis ==
Assuming a colonist sleeps for 8 hours, this implant allows them to work an additional 1/3rd of the day, and saves space on a bedroom. Even with the consciousness loss, this makes pawns have more work time, and thus better for many tasks. This assumes you don't have many sleep reducers; see [[#Comparison to reducing sleep]] for details on that.

An unfortunate side effect of the half-cycler is [[mood]]. No sleep will prevent Lovin' entirely, remove the moodlet from an impressive bedroom, and deprive a pawn of a bed's [[Comfort]] level. An [[armchair]] can provide comfort for crafter-type pawns, but all these mood-increasers are quite significant. Non-ascetic [[noble]]s still desire a bedroom that meets their needs. Also, remember that [[light|darkness]] will reduce work speed, even with a half-cycler, so you'll want to install [[light]]s around your base.

=== Work ===
The Consciousness loss has a different effect on different work types.
<br>'''Good:'''
*'''Research, Hauling, Cleaning:''' All these tasks are done slower, but have no quality, so the extra time makes up.
*'''Cooking:''' Like above; [[food poisoning]] chance is not increased.
*'''Construction, Crafting, Art:''' will produce the same-[[quality]] items, so the extra time is a net positive. Note that low-skill construction is more likely to fail.

'''Mixed:'''
*'''Plants:''' Allows more plants to be grown/harvested, but lowers yield per plant. Bad when plant space is limited, good if not.
*'''Mining:''' Good for mining regular rock or [[deep drill]]ing, bad for mining ores.

'''Bad:'''
*'''Social, Animals:''' The half-cycler is of little help: trade is limited, prisoners and animals sleep. Lowered Consciousness means more failed attempts and higher prices.
*'''Medical:''' Tends slower, with less quality, and have less successful surgeries. Tend speed is time-sensitive; speed is important, but you don't need to tend all the time.
*'''Combat:''' Worse accuracy, will get injured more, and more likely to die from Consciousness loss.
**[[EMP]] also becomes harder to use due to Brain Shock. It may be wise to EMP [[mechanoid]]s despite a half-cycler pawn being in the way, meaning you'll lose a combatant in battle.
 
Of course, pawns can be good at multiple work tasks. A pawn that mostly does Crafting can also be your main Social pawn, for instance. Each case should be weighed individually.

===Synergy with Genes{{BiotechIcon}}===
Since the half-cycler removes the need for sleep, making any effect on [[Sleep Fall Rate]] irrelevant, it synergizes well with the [[genes#sleepy|Sleepy]] and [[genes#very sleepy|Very Sleepy]] genes. Both become essentially free negative genes, providing {{+|2}} and {{+|4}} metabolic efficiency respectively. This is perhaps not enough to make the whole implant worth it alone, but on any pawn who already has a half-cycler, this is a large, completely free, secondary benefit.

=== Comparisons ===
==== Comparison to reducing sleep ====
{{For|a full list of sleep required in various circumstances|Rest#Comparison tables}}
Other than [[quick sleeper]], the following can decrease the time needed to sleep:
* High [[quality]] beds, further improved with [[royal bed]]s
* Improvements to [[digestion]] and [[blood pumping]] (like [[bionic stomach]]s, [[bionic heart]]s, and [[luciferium]])
* [[Drug]]s, like [[psychite tea]] and [[wake-up]].
* [[Sleep accelerator]]s.{{IdeologyIcon}}
* The [[Genes#Sleep|low sleep]] gene.{{BiotechIcon}}
And, of course, the [[circadian assistant]].

The following combinations warrant comparison:

'''Amazing Beds + Assistant''': In total, a masterwork bed + assistant reduce sleep to 5.04 hours - that's 21% of the day. A legendary royal bed + assistant reduces sleep to 3.96 hours (16.4% of the day). If you can easily create Masterwork/Legendary beds, such as with a [[Roles#Production specialist|Production Specialist]]{{IdeologyIcon}}, then the half-cycler can end up a ''negative'' to work compared to a circadian assistant.

'''Excellent Beds + Sleep Accelerator'''{{IdeologyIcon}}: An excellent bed + sleep accelerator reduces sleep to 5.1 hours (21.2% of the day). A legendary royal bed + accelerator reduces sleep to 3.75 hours (15.6% of the day). Note that the accelerator does cost a fair bit of hunger and power, and is only available if you have a pawn with a [[Ideoligions#Transhumanist|Transhumanist]] ideoligion.

'''Just Low Sleep'''{{BiotechIcon}}: On a normal bed, low sleep alone reduces sleep to 3.43 hours (14.26% of the day). As the half-cycler reduces practically all work by -15%, this gene is a flat out improvement. The gene comes at the cost of -4 Metabolic Efficiency, which must either be compensated with bad genes, or increase hunger by up to x200%. [[Sanguophage]]s already come with Low Sleep - installing a half-cycler is a net negative to them.

In all 3 cases, the pawn can still receive a bed's comfort, Lovin', and the Impressive Bedroom moodlets. These scenarios can be further improved with any of the other methods listed above. However, they'll have to walk to and from the bedroom/barracks, which is a minor time loss.

==== Comparison to Never Sleep{{BiotechIcon}} ====
The '''never sleep''' [[gene]] will completely prevent sleep with no Consciousness loss. However, with a metabolic efficiency of -6, it requires negative genes or ''[[genes#Archite metabolism|archite metabolism]]'' to even be used at all. It takes a large amount of negatives to negate the penalty, or 2 [[archite capsule]]s for the aforementioned metabolism gene.

Never sleep is not found in any of the default [[xenohumans]], so a [[genepack]] must be found/bought. You must also obtain a genepack to compensate for metabolism. Alternatively, you can start with a [[xenotype]] with the gene - this still comes at the genetic cost.

{{nav|body parts|wide}}
[[Category:Medical Item]] [[Category:Body Part]] [[Category:Implant]]