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BritishJournal of Psychology (2003),94, 195 –211 © 2003The BritishPsychological Society www.bps.org.uk

Aninvestigation into alleged ‘ hauntings’

Richard Wiseman 1*,Caroline Watt 2 ,Paul Stevens 2 , Emma Greening 1 and Ciara´n O’Keeffe1 1University ofHertfordshire, UK 2University ofEdinburgh, UK

Incases of alleged hauntings,a large numberof seemingly trustworthywitnesses consistentlyreport experiencing unusual phenomena (e.g. apparitions,sudden changes intemperature, astrongsense of presence) in certain locations. The two studies reported here exploredthe psychological mechanisms that underlie this apparent evidenceof ‘ ghostly’activity. The experiments took place at two locations that have a considerablereputation for being haunted —HamptonCourt Palace (Surrey, England) andthe South Bridge Vaults(Edinburgh, Scotland). Both studies involved participants walking aroundthese locations and reporting where theyexperienced unusual phenomena.Results revealed signiŽcantly more reportsof unusual experiences in areas thathad a reputationfor being haunted. This effect was notrelated to participants’prior knowledge aboutthe reputation of these areas. However,the locationof participants’experiences correlated signiŽcantly with various environmental factors,including, for example, thevariance oflocal magnetic Želds andlighting levels. TheseŽ ndingsstrongly suggest that alleged hauntingsmay notnecessarily represent evidencefor ‘ ghostly’activity, but could be, at least in part, the result of people respondingto ‘ normal’factors in their surroundings.

Recent pollsreveal that approximately38% of Americansbe lievethat ghosts exist (Gallup,2001), and 13%report havingex perienced one (MORI,1998).Such ex peri- encesinvolvea diverserange of phenomena, includingapparitions, unusual odours, sudden changesintempe rature and astrong sense of presence(Lange,Houran, Harte,& Havens, 1996).I narelativelysmall numbe rof cases,witnesse sconsistently report these experiencesin certain locations, often givingrise to the beliefthat theseplaces are ‘haunted’. Thebest of these casesappearevide ntiallyimpre ssive,some timeslasting severaly earsand involvinga largenumbe rof seeminglytrustworthywitnesses reporting unusual phenomena inthe same‘ haunted’areas (f or furtherinformation seeG auld& Cornell,1979 ;Houran &Lange,2001; I rwin,1999; M cCue,2002 ).Manyof these alleged

*Requestsfor reprints should be addressed to Dr RichardWiseman, University of Hertfordshire,HatŽ eld Campus, CollegeLane, HatŽ eld, Herts AL10 9AB, UK(e-mail:[email protected]). 196 RichardWiseman et al. hauntings havebee ndescribedin seve ralbest -sellingbooks on the paranormal,and reported on both televisionand radio(se ee.g.A uerbach,198 6). Thesehigh -proŽle c laimshave been the subjectof verylittle we ll-controlled, systematic,research.T hisis unf ortunate,inpart, becauseme diareportage of many of thesecases ex erts amajorin ue nceoverthe public’s beliefinthe paranormal(N ational ScienceBoard,2000). I naddition,such work clearlyhas the potential to contribute to our theoreticalunde rstandingof how certainpsy chologicaland psychophysiological phenomena (includinge.g. hallucination, sugge stion and response to subtle environ- mentalstimuli) operate inunusual, but naturalistic,settings (see e.g.H ouran &Lange, 1996:Houran &Williams,19 98;Lange& Houran, 1997).Thework alsocould contribute to appliedresearchinto severalimportant, and often controversial,areas, including e.g. contagiouspsy chogenicillness, sick building sy ndrome and otherforms of alleged ‘environmentalillne ss’(L undberg,1998). The present articleaddresses these issuesby outliningthe Žrst investigationsinto two internationallyknown casesof alleged hauntings. Experiment1 took placeat Hampton Court Palace.This roy alpalace was home to many Britishmonarchs for over500y ears,and itis now apopular historical attraction. Thepalac eisalso frequently referred to as‘ one of the most haunted placesinE ngland’(se ee.g.G uiley,1994;L aw,1918: U nderwood, 1971),and allegedly contains the ghost of CatherineH oward, the Žfth wifeof Henry VIII.Fifteenmonths after her marriageto the Kingin 1540, C atherineH oward wasfound guiltyof adultery and sentencedto death (Thurley,1996).L egendsugge sts that upon hearing the news,C atherineH oward ran to the Kingto pleadfor her life,but was dragged back alonga section of the Palacenow known as‘ the Haunted Gallery’(Guiley,1994; Underwood, 1971).B ythe turn of the century,the Galleryhad becomeassociated with variousunusual experiences,inc ludingsightings of a‘woman inwhite ’and reports of inexplicablescre ams(L aw,1918). Since then, visitorsto the Galleryhave reported other‘ghostly’phenomena,including a strong senseof presence,afeeling of dizzinessand sudden changesin temperature (Franklin,1998 ).The Haunted Galleryis not the only part of Hampton Court Palaceassociated with such phenomena,with visitorsand staff reportingsimilar ex periencesin other areasof the building,including an areaknown asthe GeorgianR ooms (Franklin,1998). Information about the reputation of the Haunted Galleryis widely available to the public,but speciŽc information about the locationof experiencesin areas suc hasthe GeorgianR ooms isnot widelyavailable . Experiment2 was carriedout inpart of the South BridgeV aults inE dinburgh, Scotland.E dinburgh’s South Bridgewas constructedinthe lateeighte enth century to easetransportation problemsin the city.TheBridge consisted of 19hugestone arches supporting awideroad linedwith severalthree storeybuildings.A seriesof ‘vaults’ (i.e.small c hambers,rooms and corridors) werebuilt into the Bridge’s archesto house workshops, storageareas and accommodation for the poor (Henderson, 1999).H ow- ever,ineffectivewaterprooŽ ng and overcrowdingmeant that by the mid-nineteenth century the vaultshad degeneratedinto adisease-riddenslum.T heareawas abandoned duringthe lateninete enth century,but rediscoveredand openedfor publictours in 1996.D uringsome of thesetours, both membersof the publicand guideshave experiencedmany unusual phenomena,inc luding,for example,astrong sense of presence,se veralapparitions and ‘ghostly’footsteps (Wilson,B rogan,& Hollinrake, 1999).A saresult,the vaultshave acquire daninternationalre putation for beingone of the most hauntedparts of Scotland’s capitalc ity.Thepublic has relativelyeasy ac cessto Aninvestigation into alleged ‘ hauntings’ 197 generalinformation about haunt experiencesinthe vaults,but speciŽc information about the locationof particularex periencesis not widelyavailable .

EXPERIMENT 1 TheŽ rst part of Expt 1examinedwhether participants would report adispro- portionatelylarge number of unusual experiencesin apparently ‘haunted’are asof the HauntedGalleryand the GeorgianR ooms at Hampton Court Palace.Priorto the study,Ian Franklin(I F),awarder at the palace,c ataloguedmany of the reports of unusual phenomena associatedwith the building.I Freviewedthis materialand identiŽe dareaswhe repeople had consistently reported unusual phenomena in both the HauntedGalleryand the GeorgianR ooms. The areasidentiŽ e dwere classiŽed as‘ haunted’whilst the remainingare aswere classiŽ ed as‘ controls’. The investigatorswe reblind to thesec lassiŽcations untilall data collection had been completed. Groups of participants walkedaround eitherthe HauntedGalleryor the Georgian Rooms, and reported ifthey experiencedany unusual phenomena.P articipants report- ingsuch phenomena markedthe locationsof their experienceson aoorplan. Itwas predicted that the percentageof experiencesreported inthe ‘haunted’areas in both locations would be signiŽcantly abovechanc e. Somerese archershave argued that the witnesses involvedin alleged hauntings may havehad prior knowledgeabout whichparts of abuildingwere ‘ haunted’, and that this maybe responsiblef or themreportinga disproportionately largenumber of unusual experiencesin the seareas. T hereare se veralway sinwhich this mayhappe n.F or example,witnesses’prior knowledgeabout a‘haunted’are amaycause the mto assign specialsigniŽ cance to any unusual phenomenon experienced inthat area,there fore increasingthe likelihoodof them tellingothe rs about theirex perience.Alternatively, suchinformation mayhave incre asedwitne sses’anx ietyle velswhen enteringthese areas,and this,in turn, mayhave resulted inthe witnessesexperiencingmild psychosomaticand hallucinatoryphe nomena.A second part of Expt 1evaluated whether any disproportionate reportingof unusual experiencesin ‘ haunted’areas would be due to participants’prior knowledgeabout previousre ports of ‘ghostly’ activity.Priorto visitingeithe rthe Haunted Galleryor the GeorgianR ooms, participants rated the degreeto whichtheyknew where inthese locationspeople had experienced ‘ghostly’phenomena inthe past. The ‘prior knowledge’hypothesis predicted that participants indicatinga highleve lof prior knowledgewould report agreater percen- tageof experiencesin the ‘haunted’are asthan those indicatinga lowle velof prior knowledge.O fcourse, participants canonlyreport on their prior conscious knowledge. Itisthe oreticallypossible that participants maybe inuenc ed by theirunc onscious knowledgeof haunted locations (e.g.knowle dgeacquire dearlierbut now forgotten). However,due to the difŽc ulty of assessingunconsc ious knowledge,and for easeof expression,we willuse the phrase ‘prior knowledge’throughout this articleto refer to prior conscious knowledge. Others havechallenged the ‘prior knowledge’hy pothesis,noting that witnesses oftenclaimto havebee nunawareof the reputation of a‘haunted’building prior to their experiences(see e.g.M acKenzie,1982 ).Thisposition has recently receivedempirical support from severalstudies conductedby Maherand hercolleagues(for areviewof these experiments, seeM aher,1999),using a quantitativetec hnique pioneered by 198 RichardWiseman et al. Schmeidler(1966). I nthese experiments,me diums(individuals claiming to be sensitive to the presenceof ghosts) wereaske dto walkthrough a‘haunted’building and mark oorplans to indicatewhere the yfelta ghostly presence.T heseloc ations werethen comparedto the ‘haunted’areas of the building(i.e. place sinwhich witnesses had consistently reported ghostly phenomena). Theseex perimentswere not conducted inwell -known ‘haunted’buildings and none of the participants had any prior knowledgeabout the locationsin which witne sses had reported ‘ghostly’phenom- ena.N evertheless,results from severalstudies demonstrate asigniŽcant relationship between the locationsidentiŽ ed by the mediumsand the ‘haunted’are as.T hese Žndingssugge st that many allegedhauntings maybe the result of somepeople responding to someform of ‘environmentalcue’ prese nt inapparently ‘haunted’ areas(L ange et al.,1996).Writers and researchers havesuggested a hugerange of factors to whichpe oplemay be responding (for areview,seeHouran, 1997).Some havesuggested that theselocations are actually haunted, and that peopleare responding to the presenceof adiscarnatespirit (e.g. R oberts, 1990).I ncontrast, others havesuggeste dmoremundane possibilities,including, f or example,that these areasare simply rather coldand draughty (e.g.N ickell,2001; U nderwood, 1986). Others havespec ulated about the potential roleplay ed by rathermorecontroversial physicalfac tors, including,for example,low fre quency sound waves(T andy,2000; Tandy &Lawrence,199 8),radioactivity (R adin& Roll,1994) and localmagnetic Ž elds (Roll& Persinger,2001). Athird part of Expt 1thus examinedthe potential relationshipsamong the ‘haunted’areas, participants’ reports of unusual experiencesand magneticŽ elds. Measuringof the localmagnetic Ž eldac tivity(i.e. all  uctuations between the range0 to 3kHz,whe therof naturalor artiŽcial origins) was carriedout becausea relatively largeamount of researchhas suggested astrong relationshipbetwe en alleged hauntings and magneticŽ eldswithin this range.Thiswork dates back to the mid 1980s,when Persinger(1985) speculate dthat changesin geomagne ticŽ elds(c reated e.g.by tectonic stresses inthe earth’s crust) could stimulatethe brain’s temporal lobesand produce many of the subjectiveex periencesassociatedwith hauntings. Others haveex tended these ideasto account for physicalmanife stations including, for example,c old spots, electricaleffects, popping sounds, etc.(see e.g.H ouran & Lange,1998). I napreliminarytest of this theory,Gearhart and Persinger(1986) examinedlargecase colle ctions of allegedhauntings, and reported ŽndingsigniŽ cant relationshipsbetween the timeof onset of unusual phenomena and sudden increases inglobal geomagne ticac tivity(for acritiqueof this and relatedwork, seeR utowski (1984)and Wilkinson& Gauld(1993)) .More recent support has comefrom several on-siteinvestigations of allegedhauntings that havere portedunusual localmagnetic activity(for an overview,seeRoll& Persinger,2001).Some of this work has noted that the effectseemsto be associatedwith highlevels of magneticac tivity(H algreen, Walter,Cherlow,& Cranall,1978: K onig,F raser,&Powell,1981), whilst other researchershave related the effect moreto varianceinmagnetic Ž elds(see e.g. Persinger,1985). InExpt1,the meanstre ngth and varianceof the magneticŽ eldwas measured in the Haunted Galleryand the GeorgianR ooms. Itwas predicted that therewould be signiŽcant differences betweenthe meanŽ eldstrength and variancein the ‘haunted’ and ‘control’areas. I twasalso pre dicted that there would be asigniŽcant correlation betweenthe number of unusual experiencesreported by participants ineach are a,and the mean strength and varianceof the magneticŽ eldin those areas. Aninvestigation into alleged ‘ hauntings’ 199 Method Classifying ‘haunted’and ‘control’areas IFhad catalogueda largenumbe rof reports of unusual phenomena experiencedby staff and visitorsat Hampton Court Palace(Franklin,1998 ).Thesereports dated from the end of the lastce ntury to the present day,and consisted of materialfrom newspapers, magazines,books and IF’sinterviewswith witnesses.Prior to the experiment, RWasked IFto identify wherein the Haunted Galleryand the GeorgianR ooms peoplehad consistently reportedunusual experiences.The palac esupplied oorplans of both the Haunted Galleryand the GeorgianR ooms. RWdividedeach of these oorplans into 24 equallysized are asand askedIFto markthe areasin which pe oplehad consistently reportedunusual experiences.A reasmarke dby IFwerec lassiŽed as‘ haunted’whilst unmarked areaswere classiŽ ed as‘ controls’. IFmarkedse venareas in the Haunted Galleryand sixareas in the GeorgianR ooms. These oorplans werenot seenby the investigatorsuntil all data collection had been completed.T oavoidbias, R W,the assistant experimenters,who guidedparticipants to the locations,and PS,who mapped the magneticŽ elds,were blind to the identity of these areas.

Questionnaires InQuestionnaire1 participants rated the degreeto whichthe yknew where,inthe Haunted Gallery or GeorgianR ooms, peoplehad experiencedunusual phenomena in the past (deŽnite lyy es,probably yes,unc ertain,probably no, deŽnitely no). 1 Questionnaire2 asked participants to quietly walkaround the HauntedGallery or the GeorgianR ooms, writea briefdescription of any unusual phenomena they experienced,indic atewhether theybelievedthat their experience(s) weredue to a ghost (deŽnitely y es,probably yes,uncertain, probably no, deŽnitely no) and mark where theywerestanding when theyhad their experience(s) on aoorplan. The oorplan includedin this questionnaire had not been dividedinto areas.

Procedure Participants wereself -selectingmembe rs of the publicvisiting H ampton Court Palacein lateM ay/earlyJune 2000.The yhad seenlea ets invitingthe irparticipation; thus they knew theyweretaking part ina scientiŽc investigation.P articipantstook part inone of three dailyse ssions heldove rthe course of 6days.Eachsession involveda maximumof 40people.P articipantswere Ž rst randomly splitinto two groups,acc ordingto where theyhad chosen to sit,with one halfof the room formingG roup 1and the otherhalf formingG roup 2,ina counterbalancedorder .Allparticipants then completed Ques- tionnaire1, with Group 1beingasked about their prior knowledgec oncerningthe Haunted Gallery,whilstG roup 2wereaske dabout the GeorgianR ooms. RWthengavea short talkabout scientiŽc researchinto ghosts. The talkwas prese ntedinan atmo- sphericse tting,with lowered lighting.R Wbrieydescribedthe historicaltale of CatherineH oward, asoutlined inthe introduction, but without mentioningthe location inwhich re latedhaunting-type experienceshad reportedly occurred.The talk also

1Questionnaire1 alsocontained other items including whether participants believed that ghosts exist,the frequency with whichthey had experienced ‘ ghostly’phenomena in thepast, etc. Theresults of theseitems and related analyses are reported inWiseman, W att,Greening, Stevens, and O’ Keeffe (2001). Insummary, participants reporting prior belief in ghosts reported signiŽcantly more unusual phenomena during the experiment than disbelievers, and were signiŽ cantly more likely to attribute thephenomena to ghosts. 200 RichardWiseman et al. illustratedsome of the apparatus that could be usedinhaunting investigations,such as heat-sensitivecame rasand instruments sensitiveto magneticactivity .Finally,RW outlinedthe purpose and methodology of the experiment. 2 Participantswe rethen escortedby an assistant experimenterto either the HauntedGallery(G roup 1)or the GeorgianR ooms (Group 2).O nceat the location,the participants werefree to walk around the location accordingto their individualprefe rences,and completed Questionnaire2. A lthough participants wereable to drop out of the experimentat any timewithout penalty,none did.A ssistant experimenterswere alway son hand if needed by participants when theywerein the test locations.P articipantswere also givenRW’s contact detailsin case the yrequiredfurthe radviceor information following the conclusionof the studies. The Žrst sixse ssions werepilot sessions, whose purpose was to checkthe practicabilityof the planned protocol,and to helpidentify areasf or placement of measurement equipment. Datafrom the pilotse ssions arenot includedin the analyses reported below.

Mapping the magnetic Želds Localmagnetic Ž eldswere me asured usingtwo Mag-03MS1003-axissensors feeding into alaptop computer viaa Mag-03DAMDataA cquisitionM odule(B artington Instru- ments, Witney,Oxford). Thissy stem had ameasuringrange of 100 mTwith aresolution of 0.1nT ,and recorded both staticand dynamiccomponents of the localŽ eldbe tween 0 and 3kHz.T hesystemhad asamplingrate of 1Hz.E achsensor producedthree streams of data,c orresponding to the x,yand zaxesof the localmagnetic Ž eld,with asampling rate of once per second. Thethre edata streamswe rethe ncombinedto givethe total Želdstre ngth (usingthe formulasqrt [x(squared) + y(squared) + z(squared)]), and the meanŽ eldstrength and variancewas calculate dfrom the resultingvalue s. Becausethe experimenters remainedblind to IF’sclassiŽcation of ‘haunted’and ‘control’areas, it was nece ssary to Žnd another wayof selectingareas f or placement of the instruments. Due to security and safety considerations,it was only possibleto place the magneticsensing e quipment in12 areas(six areas in the GeorgianR ooms and sixin the HauntedGallery).Theseareas were agree dupon by RWand Hampton Court Palace administrationon the basisof three criteria.F irst,to maximizethe chancesof detecting any anomaliesinthe magneticŽ elds,many of the areaschosen werethose associated with alargenumber of reports of unusual experiences,derived from the pilot sessions; others wereassociated with alownumbe rof reportedunusual experiences.Se condly, to helpminimize visitor disruption, the areaswere not locatedine speciallybusy or narrow parts of the HauntedGallery or the GeorgianR ooms. Thirdly,to minimizethe amount of timethe equipment was inplace ,the areaswere chosen such that theycould be mappedinadjace nt pairs. 3 Allmeasureme nts weremade by PS,who was blindto the

2As anadditionalinvestigation of theeffects of suggestionon reported ghostly experiences, during his introductory talk to participantsRW madesuggestions that one of thetwo locations was ‘ active’while the other was ‘ inactive’(in terms of recent frequencyof reportedghostly experiences, but giving no speciŽ c suggestionsas towhere in each location experiences had been reported).T oavoidsystematic bias, these suggestions were made in a counterbalancedfashion. For sakeof brevity,and becausesuggestion appeared to have little effect on reported experiences, this manipulation will receive no furtherattention in thisarticle. More detail of themethod and results of thismanipulation can be found in the article by Wiseman et al. (2002). 3OnceIF’ s classiŽcation of ‘haunted’and ‘ control’areas was revealed at the end of thestudy, it transpired that the 12 areaschosen by RW consistedof six hauntedand six controlareas as identiŽ ed by IF .Theanalyses for magnetic Ž elds thereforerefer to this ‘ sub-group’of six hauntedand six controlareas and not to theentire group of 13haunted and 35 controlareas. Aninvestigation into alleged ‘ hauntings’ 201 numberof unusual experiencesreported ineach of the areaswhilst setting -up and operatingthe magneticŽ eldsensors. Magneticdata wasrec orded for thirty minutesin eachare a.R ecordingtook placewhiletourists werevisiting the area,but not duringany experimentalsessions. H encethe magneticme asurement procedure would not bias participants’re ports.

Participants Therewe re678 partic ipants who eachattende d1of the 18se ssions.Some of the participants (131)were ex cludedasthe ydid not completeall of the itemson Questionnaire1 and afurther 85were ex cludedfor not completingall of the items on Questionnaire2. The numbe rof participants remainingwas 462 (163 males, 299 females;mean age: 35.0, age range: 7 to 82, SD= 16.3).A sthe 18groups of participants wereassigne dto one of the two locations,the rewas atotal of 36groups of participants.

Results Participants reportedatotal of 431unusual experiences:189 (43.8% )of these experienceswe rereported inthe Haunted Galleryand 242(56.2% )inthe Georgian Rooms; 215(46.5% )participants reportedat least one experience,and the mean numberof experiencesfor participants reportingone or moreex perienceswas 2.0 (SD= 1.45).A pproximatelytwo thirds of these experiencesinvolvedan unusual change intemperature. Theremaining one third involvedamixture of phenomena including, for example,afeelingof dizziness,he adaches,sickness, shortness of breath, someform of ‘force’,afoul odour,asenseof presenceand intense emotionalfe elings.When asked whether their experiencesweredue to aghost, 8(3.72%)participants indicated ‘DeŽnitely y es’, 22(10.23% )‘Probably yes’, 80(37.21% )‘Uncertain’, 87(40.46% ) ‘Probably no’and 18(8.37% )‘DeŽnitely no’ . ItisdifŽ cult to assessthe extent to whichthese experiencesmayhavebee nelicitedor dampenedby the contextof the pre- experimenttalk. H owever,itis worth noting that both locationswere well lit and relativelynoisy and busy with tourists and werethe refore less atmosphericthan the contextinwhich the talkwas given.G iventhesec ircumstances,it was perhaps surprisingthat so many participants reported havingex periences.

Participant grouping Eachof the 36groups completedQ uestionnaire2 whilstwalking around eitherthe Haunted Galleryor the GeorgianR ooms. Individualre sponses to the questionnaire cannot therefore be considered statisticallyinde pendent astheymayhave in uenc ed, and beeninue ncedby,othermembersof the group.F or example,friends and family members werelike lyto havesat besideone anotherand therefore to havebee nassigned to the samegroup, so theymayhave interacted morewith one anotherthan strangers might.A saresult,partic ipants’re sponses to the questionnaire werec ombinedwithin eachof the 36groups so the group isthe unit of analysis(se eRosenthal &Rosnow, 1991).

Percentage of experiences reported in ‘haunted’areas The oorplans that had beendividedinto 24areaswerephotocopie donto acetateand usedto classifythe locationof eachof the experiencesreported by participants. This 202 RichardWiseman et al. classiŽcation was carriedout by EGand CO,whilstblind to both the locationof the ‘haunted’and ‘control’areas and the results of the magneticŽ eldmeasureme nts. Given that there werese ven‘ haunted’areas in the Haunted Galleryand sixin the Georgian Rooms, singlemean t tests wereused to comparethe actualpe rcentageof experiences reported inthese areaswith the chancebaseline sof 29.16%and25%respec tively.Both analysesfound the percentageof experiencesto be signiŽcantly greaterthan chance (see Table1).

Table 1. The df ,populationmeans, t values(single group) and p values(two-tailed) comparing the percentage ofexperiences reported inthe ‘ haunted’areas ofthe Haunted Gallery andthe Georgian Roomsagainst chance

% in Degree of Population t test p hauntedareas freedom mean (singlegroup) (two-tailed)

Haunted 38.83 16 29.16 2.954 .009 Gallery Georgian 46.24 17 25 3.494 .003 Rooms

Prior knowledge Eachgroup’ s ‘prior knowledgescore’ consisted of the mean of participants’responses to the question concerningthe extent to whichthe yknew whereothe rpeoplehad reported unusual experiencesineither the HauntedGallery or the GeorgianR ooms (coded on a5-point scalefrom 1(deŽnitely y es) to 5(deŽnitely no)). Eachgroup was thenclassiŽed ashavinge ither ‘High’or ‘Low’levels of prior knowledgeon the basisof a mediansplit. This resulted in18 groups beingc lassiŽed as‘ High’(mean score = 3.89, SD= .33)and 18groups as‘ Low’(mean score = 4.51, SD= .18).The rewas a nonsigniŽcant differencebetwee nthe percentageof experiencesreported inthe ‘haunted’areas by the ‘High’and ‘Low’levels of prior knowledgegroups ineithe rthe Haunted Gallery ( t(15) = 1.66,unpaire d, p = .12,two -tailed) or the GeorgianR ooms (t (16) = ± .14,unpaired p = .89,two -tailed).

Magnetic Želds Therewas anonsigniŽcant differencein the meanmagnetic Ž eldstrength betweenthe ‘haunted’and ‘control’areas (unpaired t(10) = 1.55, p = .15,two -tailed).H owever, therewas a signiŽcant differencein the varianceof the Želdbetwee nthe two typesof areas(unpaire d t(10) = 2.34, p = .04,two -tailed),with the ‘haunted’areas ( M= 12.71, SD= 12.10)displayinga highervariance than ‘control’are as( M= 2.16, SD= 1.03). Spearmanrank correlationc oefŽcients were calc ulatedbetwee nthe numberof experiencesre ported byeachgroup within eachof the 12areasfor whichmagnetic data was obtained, and meanstre ngth and varianceof the magneticŽ eldin those areas. 4 One sample t tests werethen used to examinewhether the samplemean of these correlationsdiffered signiŽcantly from zero.T heseanaly sesreveale danonsigniŽcant

4Therewere three groups for which no experiences were reported in the 12 areas. As itwas not possible to calculate a correlationin these cases, thesethree groups were not included in the analyses. Aninvestigation into alleged ‘ hauntings’ 203 relationshipbetwee nthe numberof experiencesreported and the meanŽ eldstrength (1 sample t(32) = .82, p = .42,two-tailed).A signiŽcant relationshipwas found between the varianceof the Želdand numberof unusual experiencesreported (1sample t(32) = 2.15, p = .04,two -tailed).

Discussion Theex periment Žrst examinedwhether participants would report adisproportionately largenumber of unusual experiencesinthe ‘haunted’areas. T hese‘ haunted’areas had beenclassiŽed on the basisof prior reports. Bychance,it was ex pected that approximately29% of participants’unusual experienceswould be reported inthe ‘haunted’areas of the Haunted Gallery,and 25%inthe GeorgianR ooms. However, groups of participants visitingboth rooms reported signiŽcantly moreunusual experi- encesinthe ‘haunted’are aswithin both locations.These Ž ndingsstrongly support the notion that people’s unusual experiencesare not evenly distributedacross the locations, but instead concentrate in‘ haunted’areas. I naddition,the Žndingssuggest that the areasin which peoplereport theirex periencesareconsistent acrosstime. I n short, these empiricalŽ ndingsvalidate seve ralcharacte risticsof spontaneous haunt experiencessuggestedby anecdotal reports. Priorto enteringeither the Haunted Galleryor the GeorgianR ooms, participants wereaske dto ratethe degreeto whichthe yknew where peoplehad reported unusual experiencesinthe selocations in the past. Theresults showedthat participants’level of prior knowledgewas not signiŽcantly relatedto the percentageof experiencesreported inthe ‘haunted’areas. The seŽ ndingsdo not support the notion that the disproportio- natelylarge number of unusual experiencesreported in‘ haunted’areas is due to participants’prior conscious knowledgeabout the location. Thirdly,the experimentex aminedthe possibilitythat there weresigniŽ cant differ- encesbetween the strength and varianceof the magneticŽ eldsbetwee nthe ‘haunted’, and ‘control’, areas.R esults suggestedno signiŽcant differencesinthe meanstrength of the magneticŽ eldbetween the two types of areas.H owever,the varianceof the local magneticŽ eldwas signiŽcantly greater in ‘ haunted’than ‘control’areas, and therewas a signiŽcant relationshipbetwee nthe magneticvariance and the mean number of unusual experiencesreported by groups of participants.T hesere sults seemconsistent with previousrese archsuggesting a relationshipbetween localmagnetic Ž eldactivity and haunt reports. Experiment 2(seebelow) builtupon both the methodology and results of Expt 1. First,in E xpt 1,are aswithin the Haunted Galleryand the GeorgianR ooms were classiŽed ase ither‘haunted’or ‘control’. Experiment2 provideda moreŽ ne-grained classiŽcation of areasby usinga venue inwhic hitwas possibleto rank order eachof the areasfrom ‘most’to ‘least’‘haunted’ . Secondly,inE xpt 1,the nature of the venue resulted inparticipants havingto walkaround eachof the locationsin groups, and thus their data had to be analysed and interpreted at agroup level.U nfortunately,this resulted inthe study havinglow statistic alpower ,and itis possible that the locations, havingtourists aswell as up to 20participants walkingaround, wererelatively noisy and therefore not conduciveto haunt experiences.These issue swereovercome in E xperi- ment 2by usinga venuein whic hparticipants could visitareas on their own, and thus produce data that could be analysedand interpretedindependently.Finally,Expt 2 measured afar greaternumber of environmentalvariables. 204 RichardWiseman et al. EXPERIMENT 2 The experiment took placein 1 0of the South BridgeV aults inE dinburgh.F or the past few years,the company conducting guidedtours through the underground vaultshas maintainedacollection of any unusual experiencesreporte dby both guidesand visitors.Prior to the experiment,R Wasked Fran Hollinrake(F H),asenior tour guide,to reviewthis database and rank order the vaultsbetwe en 1(‘least haunted’, i.e.smallestnumbe rof unusual experiences)and 10(‘ most haunted’, i.e. largestnumber of unusual experiences). Thiswas refe rredto asthe ‘HauntedOrder’ of the vaults. Duringthe experiment,partic ipants wereasked to spend approximately10 minin one of the vaultson theirown, writedown any unusual phenomena theyexperi- encedand rate the degreeto whichthe ybelievedthat these experiencesweredue to aghost. Onthe basisof the results obtained inE xpt 1,it was pre dicted that there would be asigniŽcant correlationbetween the ‘Haunted Order’and mean number of experiencesreporte dine achvault.T hat is,it was predicted that the locationof past haunt reports would be predictiveof the locationof haunt reports inthe current study. The experimentalso investigated the potential relationshipbe tween participants’ prior knowledgeabout the vaultsand their reports of unusual phenomena.Prior to visitingthe vaults,partic ipants notedwhethertheyknewwherepe oplehad reported unusual experiencesin the vaultsin the past. Basedon the results of Expt 1,it was predicted that the correlationsbe tweenthe ‘HauntedOrder’, and the meannumber of experiencesreporte dineach vault, would besigniŽ cant amongparticipants who indicatedno prior knowledgeof the vaults. The experimentalso ex aminedawiderrangeof environmentalvariables than Expt 1,including,the meanstrength and varianceof the localmagnetic Ž eld,air tempera - ture, airmove ment,the vaults’interior lighting le vels,the lightingleve ldirectlyoutside the entrancesto the vaults,the oorspacesof the vaultsand their height.I twas predicted that there would be signiŽcant correlationsbetween thesevariable sand both the ‘HauntedOrder’, and the mean numberof reported experiencesineach vault.

Method Questionnaires Questionnaire1 asked participants whether theyhad heard (e.g.from friends, the media,public ations about the vaults)whe rein the vaultspeople have reported experiencingunusual phenomena (possible responses: yes,unce rtain,no). 5 Questionnaire2 instructed participants to spend afew minutes ina vaultand then report any phenomena that theyexperienced.T heywereasked to report allof their unusual experiences,no matterhow faint, and to includeall ty pesof experiences (includinge .g.unusual changesintempe rature, smells,taste s,a sense of presence,etc .). Thequestionnaire containedfour boxes,and participants wereaske dto briey describe eachof theirex periencesin one of the boxes.Theywerealso asked to ratewhether they thought that eachof their experienceswas due to aghost (deŽnitely y es,probably yes,

5Otheritems on the questionnaire asked participants whether they believed in the existence of ghosts, whetherthey believed thatthey had previously experienced a ghost, etc. TheŽ ndingswill be reported in a separatearticle. Aninvestigation into alleged ‘ hauntings’ 205 uncertain,probably no, deŽnitely no). Ifparticipants did not experienceany thing unusual thentheywereinstructe dto simplyreturn the blank questionnaire.

Procedure Theex perimentwas carriedout inA pril2001. P articipantswere self -selecting members of the publicwho had seen the experiment listedin the programmeof the Edinburgh International ScienceFestival.P articipantstook part inone of six dailysessions heldover the course of 4days.E achsession involveda maximumof 10people .TheŽ rst part took placeina privatefunction room closeto the vaults. Atthe start of the experiment,R Whanded out numbered clipboardsrandomly , whichassigne daparticipant number to eachperson. RWbrieyoutlined the purpose and procedure of the study,and demonstratedthe kinds of apparatus that could be used inscientiŽ c researchinto ghosts. RWthenasked participants to completeQ uestionnaire1. P articipantswere the ntaken asa group down to the vaultsby FH,and then takenindividuallyto avaultac cordingto theirrandomly assignedparticipant number(i.e.participant number 1went to vault1). N ote that RWwasblind to the hauntedorder so he could not introduce biasby ,say,assigning apparently suggestibleparticipants to particularvaults. F Hwasnot blindto the haunted order,but due to unevenooringand lowce ilingsin parts of the vaults herpresencewas neededfor safety insurancere asons, and she had verylimited interactions with participants. Participants spent approximately10 minin the vault and completedQuestionnaire2. D uringthis timeF Hretiredto aseparate areaof the vaultsso she did not inadvertentlyin uence participants’ re ports. Two assistant experimenters,who wereblind to the haunted order,monitoredparticipants while theycompletedtheir questionnaireand wereavailable in case any one had aquery or aproblem.P articipantsthe nreturned their questionnairesto the assistant experimenters.P articipantswe reable to drop out of the experiment at any time without penalty.Two did so. Participants werealso given R W’s contactdetailsin casethe yrequired further adviceor information followingthe conclusionof the studies.

Apparatus Magnetic Želds, air temperature andair movement Localmagnetic Ž eldswere me asured usingthe samee quipment asemployedinE xpt1, but with an increasedsampling rate of 4Hz.A irtemperature and airmove ment were measured with aTesto 445multi -purpose dataloggerconnected to aTesto Hot Bulb probe (temperature range: ± 20 to + 70C,movement:0 to 10m/s:acc uracy,samplingat arate of 0.5Hz).B oth the magneticsensors and airtemperature /movement probe were placedinto one vaultprior to eachgroup’s arrival.The participant inthe vaultwas asked to remaina fewfeetfrom the equipment to prevent potential artifacts. The equipment loggeddata for 10min.A llme asurements weremade by PS,who wasblind to the numberof unusual experiencesreporte dineach of the areaswhilst setting up and operatingthe equipment. Themagnetic sensor wassited atheadheighton alevelpart of the oor,atleast1 mawayfrom the participant and on the opposite sideof the room to any lightingcircuits. Whe nthe participant arrived,PS started the recordingand then left the vault. 206 RichardWiseman et al. Light readings andphysical dimensions The lightleve lswithin, and directlyoutside ,eachvault were measure dusinga Vital TechnologiesC orporation Tricorder.Atthe end of the experiment,R Wrecorded the lightleve lsand physicaldimensions of eachvault.L ightleve lswere re cordedfrom the centre of eachvault, and involvedpointing the lightmete rtowards eachof the wallsof the vaultand takingan averageof the readingsobtained. Thelightleve ldirectlyoutside the vaultwas obtained by placingthe lightme ter inthe centre of the vaultand pointing ittowards the doorway of the vault.

Participants The participants (N = 218) eachattende done of the 24sessions ingroups of up to 10 (91male s,127female s); meanage: 35.3 ( SD= 13.20, agerange: 11 to 77).

Results Participantsreporte datotal of 172unusual experiences:95 (43 .58%)participants reported at leastone experience,and the meannumbe rof experiencesf or participants reporting one or moreex perienceswas 1.81( SD= .94).A gain,the majorityof these experiencesinvolved an unusual changein temperature, but also includeddesc riptions of apparitions,a strong sense of beingwatched, burning sensations, strangesounds, odd odours, etc.When asked to ratewhethe rexperi- encesweredue to aghost, 1(.67%)experiencewas rated‘DeŽnitely y es’, 4(2.67%) ‘Probably yes’, 58(38 .67%)‘Uncertain’, 65(43.33% )‘Probably no’and 22(14 .67%) ‘DeŽnite lyno’ .

Hypotheses The correlationbetween the ‘Haunted Order’and the meannumber of unusual experiencesreported ineach vault, was signiŽcant ( N = 10, rho = .76, p = .02, two-tailed).

Prior knowledge Participantsindicating ‘ yes’or ‘uncertain’to the question regardingprior knowledge about where inthe vaultspeople had experiencedunusual phenomena inthe pastwere thenexcludedfrom the data ( N = 31).T he correlationbetween the ‘HauntedOrder’ and the meannumber of unusual experiencesreportedby the remainingparticipants washighly signiŽ cant ( N= 10, rho = .87, p = .009,two -tailed).

Environmental variables Table2 contains the correlationsbe tween eachof the environmentalvariables, and both the ‘Haunted Order’and the mean number of experiencesre ported by participants.O verall,the magneticŽ eldreadings varied from 47,018–51,588nT, SD from 4–32nT.Allof these measurements arewithin the natural uctuation ranges and arenot inherently anomalous.This is to be expected giventhat the vaultshad no mainswiring other than asingle,minimallighting c ircuit. Aninvestigation into alleged ‘ hauntings’ 207 Table 2. Spearman rank correlationcoefŽ cients (corrected forties), and two-tailed p values (in parentheses),between each of theenvironmental variables, and both the ‘ HauntedOrder’ and mean numberof unusual experiences reported byparticipants with no prior knowledge ofthe vaults. StatisticallysigniŽ cant values are highlightedin bold

Correlationwith Correlationwith mean number ‘HauntedOrder’ ofunusualexperiences (N = 10) (N = 10)

Magneticmean ± .2 ± .33 (.55) (.32) Magneticvariance .53 .39 (.11) (.24) Air temperature ± .22 ± .10 (.50) (.76) Air velocity .16 .43 (.63) (.19) Interiorlight levels ± .50 ± .26 (.13) (.43) Exteriorlight levels .74 .84 (.03) (.01) Floorspace .73 .58 (.03) (.08) Height .65 .64 (.05) (.05)

GENERAL DISCUSSION Theresults of Expts 1and 2arehighly c onsistent, with around 45%ofparticipants in eachexperiment reporting at leastone unusual experience.Some of these experiences werepowerful for participants and wereinterprete dasbe ingdue to aghost. Regardless of their interpretation by participants,all of these experiencesareimportant and relevantto the question of the phenomenology of haunt experiences,as the ygivean indication of the incidenceand nature of unusual experiencesunder controlled conditions ina potentiallyhaunte dlocation.I naddition,it has beenarguedthat the interpretation of such unusual experiencesmaybe mediatedby contextualvariable s (Lange et al.,1996),such that the sameex periencemay in one contextbe interpreted as ghostly,and inanothe rcontextbe interpretedashaving a non-paranormalorigin. Experiment 1took placein a relativelywell lit and busy locationin whic hparticipants mingledasa group.I ncontrast, the settingfor Experiment2 wasquie t, dank and dimly lit,and participants werealone while the yrated their vault.While some aspe cts of the Hampton Court Palacesettingmay not havebe en conduciveto ghostly experiences compared to the South BridgeV aults,perhaps surprisinglya similarproportion of experienceswas reported ine achlocation.H owever,haunt experiencescan and do occur ingroup settings and someauthors haveeve nsuggestedthat group contagion effects mayincre asere ports of haunt experiences(Lange& Houran, 1998,1999). I tis therefore possiblethat group contagion effects mayhave counte racted to someex tent the lessc onduciveaspe cts of the locationin the Hampton Court Palacestudy . Theunusual experiencesreportedby participants inour two studiesarecomparable to many of the experiencesthat havebe enreported inthe past inthe two locations. 208 RichardWiseman et al. Thesepast reports havecontributed to the ‘haunted’reputation of Hampton Court Palaceand the South BridgeV aults.T herefore, our Žndingscan facilitate an under- standingof thesealleged hauntings. O ur studies areperhaps less pertinent to highly documentedcasesin which a seriesof witnesseshavereporte dseeingthe same apparition overalongperiod of time(e .g.G auld& Cornell,1979; M acKenzie,1982). Howeverit has been noted(e.g.B eloff, 2001)that suchcasesarere lativelyrare.A lso,the settingof our studies, inlocations with hauntedreputations, mightnot be directly comparableto those caseswhe reunex pected experiencesoc cur,for examplewhe nthe experient had no prior conscious knowledgethat the sitemight be haunted. InExpt 1,partic ipants reported adisproportionately largenumber of unusual experiencesin ‘ haunted’areas. I nExpt2,there was asigniŽcant correlationbetwee n the ‘HauntedOrder’and the meannumbe rof experiencesreported ineach vault. Together,theseŽ ndingsprovide strong support for the notion that witnesses’reports of unusual experiencesare not evenlydistributed throughout the locations,but areinstead concentratedince rtainare as.I naddition,the ysuggestthat the locationsin whic htheir experiencesare re ported arehighly consistent overtime,as these arethe areasin which most experienceshavebe enreported inthe past. Both experimentsalso asse ssedthe notion that this clusteringof reports could have been due to participants havingprior knowledgeabout wherepeople have reported unusual experiencesinthe past. Thisidea has beenproposed to account for many cases of allegedhauntings. H owever,the results from both experimentsprovided no support for this hypothesis.I nExpt 1therewe reno signiŽcant differencesbetween the proportion of unusual experiencesreportedinthe ‘haunted’are asby groups of participants with ‘high’and ‘low’leve lsof prior knowledge.Inthe second experiment the correlation,between the ‘Haunted Order’and the meannumber of experiences reported ineac hvault,was signiŽ cant amongparticipants with no prior knowledge. Although wecannot ruleout the possibleeffec ts of priming,ex pectation, and beliefin the paranormalto account for people’s reportedexperiences,these results strongly suggestthat conscious ‘prior knowledge’doe snot account for the clusteringof experiencesin c ertainlocations within the two test sites.T he Žndingthat locations whereex periencesarereported isc onsistent overtime,irrespectiveof prior knowledge,conceptually replicate spreviousŽ eldwork (e.g.M aher& Schmeidler, 1975;Sc hmeidler,1966). Thirdly,both experimentsalso ex aminedwhether the allegedhaunting maybe due, at leastin part, to participants responding to environmentalcues. I nExpt1,the variance of the localmagne ticŽ eldin the ‘haunted’areas was signiŽcantly gre ater than of the ‘control’are as.I naddition,the number of unusual experiencesre ported by participants was correlatedwith magneticvarianc e.Thiswas not replicatedin E xpt2,whichfound a nonsigniŽcant positivecorrelation between magneticvarianc eand the haunted order. Thesere sults providesome support for the controversialthe ory that the presenceof certainty pes of localmagnetic Ž eldsmay impac tupon arangeof psychological, psychophysiologicaland health-relatedvariables(K orinevskaya,K holodov,& Korinevskii,1993; V oustianiouk &Kaufmann, 2000).A controlledlaboratory study by Stevens(2001), for instance,showed psychologicaland physiologicalreac tions to a changingmagnetic Ž eldof comparablemagnitude to those measured inour two experimentalvenues. E vensubtle psychologicaland physiologicalchanges occ urring ina contextthat mightsugge st paranormaleve nts (e.g.occ urringto aperson who believesin ghosts, occurringin a locationwith ahaunted reputation) maylead to that person makinga ‘paranormal’attribution to what theymightothe rwiseinterpret asan Aninvestigation into alleged ‘ hauntings’ 209 ambiguousstimulus. A ndithas beenshown that experimentallyapplie dweakmagnetic Želdscan lead to morepowe rful and compellingex periences,suc hasa sensed presence,that aredire ctlyc omparableto the kinds of experiencesthat aresponta - neouslyreported (e.g.P ersinger,2001).SuchŽ ndingssuggest that magneticŽ elds,along with arangeof other variables,toge thermayacc ount for somehaunting experiences. Results from Expt2alsosuggeste dthat visualfeature sof the environmentmayplay a keyrolein causing people to report unusual experiences.The position of vaultsin the ‘HauntedOrder’was positivelycorre latedwith the lightlevel directly outside the vault, oorspace and height.I naddition,the mean number of unusual experiencesreported in the vaultswas positively correlated with exterior lightle velsand height.The seŽ ndings could be interpretedinseveral way s.F or example,it is possible that thesevisual fe atures mightmatch the stereotypeof atypically‘ haunted’place held by participants,and thus inducemild psy chosomaticand hallucinatoryex periences.A lternatively,thesefeatures mightdirectly cause unusual physicaland psychologicalex periences.F or example, participants walkingfrom arelativelywe ll-litcorridor into amuchdarker vaultmay causethem to experiencethe typesof unusual phenomena associatedwith mildse nsory deprivation(see e.g.M unro &Persinger,1992;T iller& Persinger,1994).L ikewise, especiallylarge or highvaults may have cause dparticipants to feelespecially vulne rable and uneasy.Finally,these variablesmay covary with another factor (e.g.the production of unusual shadows) whichare responsible for the reporting of unusual experiences. Future work should attempt to teaseapart these competinginte rpretations of the phenomena by recordingthe numberof unusual experiencesreported by participants whilstsy stematicallymanipulating the sefactors (e.g.lighting levels and the varianceof the localmagnetic Ž eld).M ultivariatemodelling could be employed infuture to understand the relativeimportanc efor haunt experiencesof the varietyof environ- mentaland psychologicalfac tors that havebee nhighlightedby investigationssuc has ours. Asarguedby Houran and Lange(1996), no singlephy sicalmec hanismis likely to account for allcases of haunts. Inshort, both of theseex perimentshave y ieldedc onsiderableinsight into these two alleged‘ hauntings’. Both experimentshave de monstrated that the reputation of these locations isnot basedupon questionable eyewitness testimony,nor canthe distribution of the experienceswithin the sitesbe explainedbywitnesses’prior knowledge.I nstead, the data strongly support the notion that peopleconsistently report unusual experi- encesin‘ haunted’areas because of environmentalfac tors, whichmaydiffer across locations.F urther,our experiments havestarted to identify someof thesefactors, includingthe varianceof localmagnetic Ž elds,size of locationand lightingleve ls— stimuliof whichwitnesses maynot be consciouslyaware. T aken together,these Žndings strongly suggestthat these allegedhauntings do not represent evidencefor ‘ghostly’ activity,but areinstead the result of peopleresponding —perhaps unwittingly—to ‘normal’fac tors inthe irsurroundings.

Acknowledgements The authorswould liketo thank IanB aker,RobertC halmers,D rIllyaEigenbrot,Ian F ranklin, ChristopherG idlow,Ricky Glover,FranH ollinrake,D rJamesH ouran, Dennis McGuinnes, ProfessorR obertM orris,E lizabethWhidde tt,R achelWhitburn, JeffreyWisemanand our referees fortheir invaluable advice and assistancewith thesestudies. W ewould alsolike to thank BartingtonInstruments, H ampton Court Palace,theE dinburgh InternationalSc ienceF estival, 210 RichardWiseman et al. MercatT ours,L and Infrared, L’OrielT echnology,Testo,the P errottW arrickF und, COPUS,and Philip HarrisE ducation forsupporting thiswork.

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Received18 September2001; revised version received13 February2002