Stress facilitates classical conditioning in males, but impairs classical conditioning in females through activational effects of ovarian hormones

Gwendolyn E. Wood, Tracey J. Shors · Proceedings of the National Academy of Sciences · 1998 · neuroscience · 10.1073/pnas.95.7.4066 · record wood1998-stress-facilitates-classical-condi
tag layer · index · concepts · authors · עברית
Where this record's text came from. faceted 2026-08 by reading the locally held text (html); every evidence string verified as an exact substring of that text before merging. Claim relations is empty: the article uses numbered reference markers throughout and never names a prior author or study in the running text when relating its own findings to earlier work, so no relation could be anchored to named prior work without inference. The paper does mention a subsequent proestrus study ('a study subsequent to those presented here established...'), but that is a later study citing this one rather than a relation this paper draws to named prior work. Claim type was set to 'mechanism' rather than 'existence' because the paper's stated advance is the hormonal dependence, not merely the occurrence of the sex difference. 2026-08-12, 2026-08-13 and 2026-08-15 schema-0.3 passes: every quote verified as an exact substring of the staged text and anchored at merge time; concept terms verified present; every edge endpoint an existing node.
2 quotations on this page contain a reference number where the paper printed a superscript. This journal style prints citations as raised numerals — parameters12,13 — and the extraction flattened them into the line, so the sentence reads parameters 12 , 13 . The digits are citation markers and not part of what the author wrote. The quotes keep them for the same reason they keep every other extraction fault: a quote is reproduced exactly or it proves nothing.
How to read this page. The article itself is not reproduced here — this paper is not cleared for redistribution, so what follows is the tag layer alone. The evidence sentences are withheld with the article. The table at the foot lists every tag the record carries; each row names the facet it belongs to, and the whose words column says whether the tag records the paper's own wording or the tagger's sentence about the paper. Every tag links to each other paper in the corpus carrying it. The machine-readable edition of the same thing is the TEI file beside this one, where the tags live in standOff, and the article is at its publisher via the link below. When we have changed our mind. Some entries in the table begin with a word in capitals and the reason for it. EVIDENCE CORRECTED — the finding still stands, but we had quoted the wrong sentence from the paper, and the quotation has been replaced with the right one. RETRACTED — the entry itself was wrong; it stays on the page, marked, with the reason, rather than being deleted. WITHDRAWN AND REPLACED — the entry was wrong, and a corrected version of it appears in the entries below. Each mark carries its own reason, in brackets, because the reasons differ from one entry to the next. An entry we have WITHDRAWN is removed from this page and kept in the record, with its reason. A line reading Audit and a date is a later re-reading of the entry against its whole sentence: DOUBTFUL means it was kept, and the reason says what is loose about it. Quotation marks inside the tagger's sentence. Where a tag is the tagger's own sentence, a phrase in quotation marks inside it is borrowed from the paper — the tagger's wording around it is not. The paper's own sentence is the evidence quote for that row; on this page it is withheld with the article, and the article is at its publisher. Nothing inside quotation marks anywhere on this page is ours: if it is quoted, it is the paper's. Whose words a concept carries. A concept entry records a term the paper itself uses, so the term, the sense given for it, and its evidence are the paper's own words, quoted where the paper fixes them. This is the opposite of a sense entry in the tag table, which is the tagger's sentence about how the paper uses a term. Where a concept entry could not be grounded in the paper's words, the entry says so on its own row.
Other fields define these differently the same word, defined another way in another discipline
sex 3 fields · standard deviation 3 fields

Tags on this paper

Every tag the record carries, each linking to every other paper in the corpus that carries it. A tag appears here whether or not its words occur in the article — the spans below are only the ones a sentence in this paper licenses. Of the 32 concept tags on this paper, none is grounded in a quoted sentence. All carry the tagger's gloss of what the term means in this paper, which is not something the article can license.
classical conditioning operant conditioning instrumental conditioning learned helplessness conditioned eyeblink response conditioned stimulus unconditioned stimulus sensitized responses pseudoconditioning delay paradigm stressor ovarian hormones estrogen progesterone ovariectomized tamoxifen estrogen receptors estrous cycle proestrus diestrus vaginal cytology activational effects tailflick response analgesia hypothalamic-pituitary-adrenal axis glucocorticoids dendritic spine density NMDA receptor spontaneous blink rate active avoidance pseudopregnancy passive avoidance Stress impairs female conditioning by acting through circulating estrogen binding to available estrogen receptors, so removing either the hormone or the receptor blocks the impairment Stress disrupts ovarian hormone levels, and that disruption in turn impairs learning Stress raises glucocorticoids through a sexually dimorphic hypothalamic-pituitary-adrenal response, and the glucocorticoid rise disrupts estrogen and progesterone Estrogen changes intracellular calcium through L-type calcium channels and NMDA receptor activation, altering synaptic density and efficacy and thereby the rate of learning tailshock NMDA sexually dimorphic electromyographic obicularis oculi conditioned response sensitized response Conditioned responses eyeblinks Sham surgery ceiling effect estrus sex acquisition of the conditioned eyeblink response analgesic responses intertrial interval rate of acquisition of the conditioned response stressor exposure CS intensity paired ( n = 7) or explicitly unpaired ( n = 4) conditioning stimuli ANOVA interaction effect A significant interaction between stress, sex, and paired vs. unpaired training post hoc multiple comparison test Newman–Keuls comparison test Cochran's Q test Cochran Q test standard deviation p-value F significant interaction SD behavioural-experiment

Legend

second readingalternativesan independent re-reading of a facet, recorded whether or not it agrees
relation to other workclaim_relationshow this paper stands to another: agrees, contradicts, extends, qualifies
claim typeclaim_typethe shape of the claim: existence, mechanism, method, critique, prediction, null
concept edgeconcept_edgesan asserted relation between two concepts, with the sentence asserting it
content tagcontent_tagsa finding, definition, quantity, statistic or variable named in the paper
contributioncontributionwhat the paper claims to add
controlcontrolsan experiment run to eliminate a rival explanation
limitationlimitationswhat the paper says its evidence cannot support
mechanismmechanismshow the reported effect is said to come about
methodmethodhow the paper produced its evidence
object of studyobject_of_studywhat the paper is about — the thing it investigates
phenomenonphenomenonthe effect or regularity under study
research questionresearch_questionthe question the paper sets itself
sensesensesa distinct use of a term, quoted where the paper fixes it
transfertransfersa method or concept carried in from another field

The paper

The full text is not reproduced here. This article is not cleared for redistribution, so the page carries the tag layer only. Its evidence sentences are withheld; the grounding status remains with each tag, and the article itself is at https://doi.org/10.1073/pnas.95.7.4066. The reading view exists for the papers whose licence permits it.

Every tag on this page

alternatives 3 · claim_relations 6 · claim_type 1 · concept_edges 10 · content_tags 89 · contribution 1 · controls 3 · limitations 9 · mechanisms 15 · method 1 · object_of_study 1 · phenomenon 1 · research_question 1 · senses 7 · transfers 2

Relations on this page carry a quotation for the claim. Where a relation was separately evidenced — and so tested against the vocabulary for its type — the row says so; none of 10 relations here carry that mark. The rest are the tagger’s reading of the sentence quoted beside them.

facettagfieldconf.whose words
object_of_studythe effect of an acute stressor on acquisition of the classically conditioned eyeblink response in male and female rats, and the role of ovarian hormones in the female effect
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object_of_studythe paper's words
research_questiondoes stress enhance classical eyeblink conditioning in females as it does in males
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research_questionthe paper's words
contributionshows that the same stressor has opposite effects on associative learning in males and females, and that the female impairment requires ovarian hormones and available estrogen receptors
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contributionthe paper's words
claim_typemechanism
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claim_typethe paper's words
phenomenonsexually dimorphic stress effects on classical eyeblink conditioning
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phenomenonthe paper's words
methodbehavioural-experiment
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methodthe paper's words
mechanismsmechanisms
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mechanisms[0]the tagger's words
mechanismsmechanisms
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mechanisms[1]the tagger's words
mechanismsmechanisms
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mechanisms[2]the tagger's words
mechanismsmechanisms
Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above.
mechanisms[3]the tagger's words
mechanismsthe paper's premise is a stated absence: the experiment exists because the question had never been asked of females
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mechanisms[4]1.0the tagger's words
mechanismsthe ceiling explanation is not argued away but engineered away: the CS intensity is lowered until unstressed females start where unstressed males started, and the impairment survives
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mechanisms[5]1.0the tagger's words
mechanismstwo independent routes to the same conclusion: take out the organ that makes the hormone, then leave the organ and block the receptor instead
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mechanisms[6]0.95the tagger's words
mechanismsthe two converging routes do not agree in every detail, and the paper reports the disagreement rather than resolving it by preference
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mechanisms[7]0.95the tagger's words
mechanismsa ladder of nonspecific explanations is eliminated one at a time with its own control — pseudoconditioning, sensitization, spontaneous blinking, first-trial responding, analgesia and motor activity
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mechanisms[8]1.0the tagger's words
mechanismsthe first trial is used as a control on the manipulation itself: if the stressor made animals respond to the tone directly, it would show before any learning was possible
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mechanisms[9]0.95the tagger's words
mechanismsthe reflex itself is used as an argument that motor differences cannot explain the result, since every animal must produce the unconditioned response
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mechanisms[10]0.95the tagger's words
mechanismsthe hormonal state is read out independently of the manipulation, by vaginal cytology, so the antagonist's effect can be confirmed rather than assumed
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mechanisms[11]0.95the tagger's words
mechanismsa continuous cycle is collapsed into three stages by the authors, chosen to correspond to circulating hormone levels rather than to the underlying cytological detail
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mechanisms[12]0.95the tagger's words
mechanismsa transient effect and a persistent one are separated by looking at where each has gone by the end of training: the baseline sex difference washes out, the stress effect does not
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mechanisms[13]0.95the tagger's words
mechanismsan unexpected reversal is reported rather than buried: ovariectomised females responded MORE after stress, putting them on the male side of the effect
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mechanisms[14]0.95the tagger's words
limitationsSex and stress each independently affect performance in learning tasks, which complicates attributing the observed differences to learning.
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what this limits: any attribution of the effect to sex or to stress singly: EVALUATING THE CONTRIBUTION OF SEX AND STRESS TO LEARNING IS COMPLICATED BY THE FACT THAT BOTH VARIABLES ALTER PERFORMANCE IN LEARNING TASKS
limitations[0]the tagger's words
limitationsThe ovariectomy result may reflect progesterone rather than estrogen, since removal of the hormone and blockade of its receptor gave different outcomes.
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what this limits: the estrogen interpretation of the ovariectomy result: THE RESULTS MAY SUGGEST A CRITICAL ROLE FOR PROGESTERONE IN THE IMPAIRED PERFORMANCE ASSOCIATED WITH OVARIECTOMY
limitations[1]the tagger's words
limitationsHormone removal and receptor blockade did not have equivalent consequences for learning, so the cellular route of the effect is unresolved.
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what this limits: any inference that treats hormone removal and receptor blockade as the same evidence: REMOVAL OF ESTROGEN HORMONE AND BLOCKADE OF ITS RECEPTOR DO NOT NECESSARILY HAVE SIMILAR CONSEQUENCES ON LEARNING AND MAY ACTIVATE DIFFERENT CELLULAR PROCESSES
limitations[2]the tagger's words
limitationsthe two hormones cannot be separated by ovariectomy, which removes both estrogen and progesterone
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what this limits: the same scope as limitations[1] - ovariectomy removes estrogen and progesterone together, so the two hormones cannot be separated by it
limitations[3]0.95the tagger's words
limitationsthe antagonist is not clean at the receptor-subtype level
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what this limits: the receptor-specificity of the pharmacological result: ESTROGEN HAS AT LEAST TWO TYPES OF NUCLEAR RECEPTORS ... AND TAM HAS BINDING AFFINITY FOR BOTH TYPES OF RECEPTORS TO VARYING DEGREES
limitations[4]0.9the tagger's words
limitationsthe estrous stage was not controlled in the main experiments, so the effect may be carried by one phase of the cycle
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what this limits: the main stress effect, which may be carried by one phase of the cycle: THE EFFECTS OF STRESS ON ACQUISITION OF THE CR [may be] MEDIATED BY THE STAGE OF ESTROUS AND LEVELS OF CIRCULATING ESTROGEN
limitations[5]0.95the tagger's words
limitationsovariectomy itself was not inert — it raised sensitized responding, and the paper has to argue that the increase is too small to matter
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what this limits: the sensitization comparison specifically: OVARIECTOMY ALONE ENHANCED THE NUMBER OF SENSITIZED RESPONSES ... [called] THIS MINOR INCREASE - the surgery moved the baseline it was meant to hold still
limitations[6]0.95the tagger's words
limitationssex and stress are entangled as explanatory variables because each alters performance on its own
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duplicate of: limitations[0] · what this limits: the same scope as limitations[0] - sex and stress are entangled because each alters performance on its own
limitations[7]0.95the tagger's words
limitationsthe mechanism linking stress to the hormones is proposed, not shown
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what this limits: the mechanistic account only: THE STRESS-INDUCED IMPAIRMENT OF LEARNING IN FEMALES MAY BE MEDIATED BY A STRESS-INDUCED DISRUPTION OF OVARIAN HORMONES - proposed, not shown
limitations[8]0.95the tagger's words
transfersvaginal smear staging, imported as an independent readout of hormonal state so that a behavioural manipulation can be checked against circulating estrogen
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transfers[0]0.95the tagger's words
transferstamoxifen, a clinical antiestrogen, repurposed as a laboratory tool for asking whether a behaviour requires estrogen receptors
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transfers[1]0.95the tagger's words
controlssham surgery reproducing every part of the ovariectomy except the removal itself
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eliminates: the surgery, anaesthesia and handling as the cause of any difference attributed to loss of the ovaries - the single difference is named in the sentence · outcome (stated by the tagger, no quotation): held
controls[0]0.85the tagger's words
controlsmeasurements of spontaneous blinking, sensitization and pseudoconditioning alongside the conditioning result
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eliminates: three alternatives at once - nonspecific effects of stressor exposure on blinking, sensitization, and pseudoconditioning · outcome: held
controls[1]0.95the tagger's words
controlscomparison of analgesia following tailshock between males and females
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eliminates: a sex difference in stress-induced analgesia as the reason the conditioning effects run in opposite directions · outcome (stated by the tagger, no quotation): held
controls[2]0.9the tagger's words
sensesconditioning — classical versus operant/instrumental; stress moves them in opposite directions, which is the dissociation the paper is built on
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senses[0]0.95the tagger's words
senseseyeblink — conditioned response (at least 80 ms after CS onset, before US onset) versus sensitized response (within 80 ms of CS onset); the same movement counted as two different things by latency
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senses[1]1.0the tagger's words
sensesimpairment — as a stress effect within females, versus as an ovariectomy effect in unstressed females; the paper finds both and keeps them apart
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senses[2]0.95the tagger's words
sensesremoving estrogen — by taking out the source (ovariectomy) versus by blocking the receptor (tamoxifen); the paper shows these are not equivalent operations
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senses[3]1.0the tagger's words
sensessex difference — the baseline one (unstressed females learn faster, and it washes out with training) versus the stress-induced one (opposite signs, and it persists)
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senses[4]0.95the tagger's words
sensesestrous stage — the full cytological sequence versus the simplified three-stage scheme the authors impose to track circulating hormone levels
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senses[5]0.95the tagger's words
senseshormone effects — activational, depending on what circulates in the adult, as against the organisational sense implied by the title's contrast
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senses[6]0.9the tagger's words
alternativesclaim_type: existence
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a second reading DIFFERING from the recorded value. Recorded: mechanism — note: a second reading, verbatim-verified, disagreeing with the value on the record. Not applied - a person decides.
alternatives.claim_typethe tagger's words
alternativesmethod: classical eyeblink conditioning in rats with implanted periorbital electrodes, 24 h after restraint-and-tailshock stress, crossed with ovariectomy and with estrogen-receptor blockade
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a second reading DIFFERING from the recorded value. Recorded: behavioural-experiment — note: a second reading, verbatim-verified, disagreeing with the value on the record. Not applied - a person decides.
alternatives.methodthe tagger's words
alternativesphenomenon: sexually dimorphic effects of stress on associative learning
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a second reading DIFFERING from the recorded value. Recorded: sexually dimorphic stress effects on classical eyeblink conditioning — note: a second reading, verbatim-verified, disagreeing with the value on the record. Not applied - a person decides.
alternatives.phenomenonthe tagger's words
claim_relationsextends → the male-only literature on stress-induced facilitation of classical conditioning (refs 10–15), by asking the same question of females for the first time
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claim_relations[0]1.0the tagger's words
claim_relationsextends → reports that stress-induced helplessness is reduced or absent in females (refs 6–9)
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claim_relations[1]0.95the tagger's words
claim_relationscontradicts → the expectation, stated as the paper's own hypothesis, that stress would enhance conditioning in females as it does in males
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claim_relations[2]0.95the tagger's words
claim_relationssupports → the body of evidence implicating estrogen in memory formation, including clinical work on estrogen and Alzheimer's
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claim_relations[3]0.95the tagger's words
claim_relationssupports → a later study establishing that the female impairment occurs preferentially in proestrus
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claim_relations[4]0.95the tagger's words
claim_relationscritiques → an activity-difference explanation of sex effects in learning tasks
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claim_relations[5]0.9the tagger's words
concept_edgesclassical conditioning —contrasted-with→ instrumental conditioning
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strength of the relation: 0.95
concept_edges[0]the tagger's words
concept_edgeslearned helplessness —operationalised-as→ operant conditioning
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strength of the relation: 0.85 Audit 2026-09-28: DOUBTFUL - read against its full span and kept, but endpoint by anaphora: 'The impairment' = learned helplessness (previous sentence); operationalised-as is loose.
concept_edges[1]the tagger's words
concept_edgesestrogen —part-of→ ovarian hormones
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strength of the relation: 0.95 Audit 2026-09-28: DOUBTFUL - read against its full span and kept, but the span writes 'Female sex hormones ... produced by the ovaries', not 'ovarian hormones'.
concept_edges[2]the tagger's words
concept_edgesconditioned eyeblink response —distinct-from→ sensitized responses
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strength of the relation: 1 Audit 2026-09-28: DOUBTFUL - read against its full span and kept, but the span writes 'Conditioned responses (CRs)', not 'conditioned eyeblink response'.
concept_edges[4]the tagger's words
concept_edgesestrous cycle —operationalised-as→ vaginal cytology
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strength of the relation: 1
concept_edges[5]the tagger's words
concept_edgesanalgesia —operationalised-as→ tailflick response
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strength of the relation: 1 Audit 2026-09-28: DOUBTFUL - read against its full span and kept, but the span writes 'analgesic responses', not 'analgesia'.
concept_edges[7]the tagger's words
concept_edgesEVIDENCE CORRECTED (RE-GROUNDED) · estrogen —causes→ dendritic spine density
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EVIDENCE CORRECTED: RE-GROUNDED. The old span said 'the density of…', which does not attest the endpoint 'dendritic spine density' as a word. This sentence uses the paper's own compact form and states the effect: estrogen 'is reported to ENHANCE…'. — strength of the relation: 0.9 Audit 2026-09-28: DOUBTFUL - read against its full span and kept, but attributed/hedged: estrogen is REPORTED to enhance spine density.
concept_edges[8]the tagger's words
concept_edgesovarian hormones —causes→ hypothalamic-pituitary-adrenal axis
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strength of the relation: 0.7 Audit 2026-09-28: DOUBTFUL - read against its full span and kept, but endpoint by anaphora: 'these sex differences in the stress response' = HPA axis activation (previous sentence); the span says DEPENDENT ON, causes is loose.
concept_edges[9]the tagger's words
concept_edgesclassical conditioning —operationalised-as→ delay paradigm
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strength of the relation: 0.95 Audit 2026-09-28: DOUBTFUL - read against its full span and kept, but the span writes 'A delay paradigm was used', not 'classical conditioning'.
concept_edges[11]the tagger's words
concept_edgesactive avoidance —contrasted-with→ passive avoidance
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strength of the relation: 0.95
concept_edges[12]the tagger's words
content_tagsANOVA
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also in: ANOVA
content_tags.statistics[0]the tagger's words
content_tagsinteraction effect
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content_tags.statistics[1]the tagger's words
content_tagspost hoc multiple comparison test
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content_tags.statistics[2]the tagger's words
content_tagsCochran's Q test
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content_tags.statistics[3]the tagger's words
content_tagsstandard deviation
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content_tags.statistics[4]the tagger's words
content_tagsp-value
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also in: p-value
content_tags.statistics[5]the tagger's words
content_tagsF
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also in: F
content_tags.statistics[6]1.0the tagger's words
content_tagsNewman–Keuls comparison test
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content_tags.statistics[7]1.0the tagger's words
content_tagsCochran Q test
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content_tags.statistics[8]1.0the tagger's words
content_tagssignificant interaction
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content_tags.statistics[9]1.0the tagger's words
content_tagsSD
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also in: SD
content_tags.statistics[10]1.0the tagger's words
content_tagsThe same stressor had opposite effects by sex: it speeded acquisition of the conditioned eyeblink response in males and slowed it in females, each relative to its own unstressed controls.
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content_tags.findings[0]the tagger's words
content_tagsWithout stress, females acquired the conditioned response faster than males.
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content_tags.findings[1]the tagger's words
content_tagsRemoving the ovaries abolished the stress-induced impairment: stress impaired acquisition in females with intact ovaries but not in ovariectomized females.
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content_tags.findings[2]the tagger's words
content_tagsBlocking estrogen receptors with tamoxifen also abolished the impairment: stress impaired acquisition in vehicle-injected females but not in tamoxifen-injected females.
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content_tags.findings[3]the tagger's words
content_tagsThe opposite effects of stress on the two sexes were not caused by changes in spontaneous blinking, sensitization or pseudoconditioning.
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content_tags.findings[4]the tagger's words
content_tagsAfter stressor exposure, females remained significantly impaired relative to unstressed females.
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content_tags.findings[5]the tagger's words
content_tagsStressed males and stressed females did not differ in pain sensitivity as measured by tailflick latency, so the sex-opposite learning effects were not caused by differences in analgesia.
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content_tags.findings[6]the tagger's words
content_tagsLate in training, stressed ovariectomized females actually responded more than unstressed ovariectomized females, that is, they showed the male-like facilitation once ovarian hormones were gone.
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content_tags.findings[7]the tagger's words
content_tagsOvariectomy on its own impaired learning in unstressed females during the later part of acquisition.
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content_tags.findings[8]the tagger's words
content_tagsBy the last 100 trials, unstressed males performed at a similar rate to unstressed females.
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content_tags.findings[9]the tagger's words
content_tagsthe same stressor had opposite effects by sex — facilitating acquisition in males and impairing it in females
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content_tags.findings[10]1.0the tagger's words
content_tagsunstressed females outperformed unstressed males
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content_tags.findings[11]1.0the tagger's words
content_tagsthe baseline sex difference was gone by the last 100 trials
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content_tags.findings[12]1.0the tagger's words
content_tagsafter stressor exposure females were still significantly impaired relative to unstressed females
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content_tags.findings[13]1.0the tagger's words
content_tagsstress impaired acquisition in females with intact ovaries but not in ovariectomised females
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content_tags.findings[14]1.0the tagger's words
content_tagsovariectomised females went the other way late in training, responding more after stress — the male pattern
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content_tags.findings[15]1.0the tagger's words
content_tagsblocking estrogen receptors with tamoxifen prevented the stress-induced impairment, while the injections alone had no effect on acquisition
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content_tags.findings[16]1.0the tagger's words
content_tagsremoving ovarian hormones impaired performance in the last 100 trials of training
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content_tags.findings[17]1.0the tagger's words
content_tagsno sex difference in spontaneous blink rate, in responses to the tone before training, or to explicitly unpaired stimuli
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content_tags.findings[18]1.0the tagger's words
content_tagsstressed males and stressed females did not differ in tailflick analgesia, so the effect is not a pain-sensitivity difference
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content_tags.findings[19]1.0the tagger's words
content_tagsunstressed females reached 72% responding in the first 20 trials against 37% for unstressed males
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content_tags.findings[20]1.0the tagger's words
content_tagstamoxifen produced a diestrus cytology in 20 of 21 females, confirming the intended low-estrogen state
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content_tags.findings[21]1.0the tagger's words
content_tagsovariectomy alone roughly doubled sensitized responding, from under 1 in 10 to 2 in 10
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content_tags.findings[22]1.0the tagger's words
content_tagsthe stressor did not produce responses to the tone on the very first trial, before learning was possible
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content_tags.findings[23]1.0the tagger's words
content_tagslearned helplessness
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content_tags.definitions[0]the tagger's words
content_tagsconditioned response
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content_tags.definitions[1]the tagger's words
content_tagssensitized response
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content_tags.definitions[2]the tagger's words
content_tagslearned helplessness
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content_tags.definitions[4]1.0the tagger's words
content_tagsConditioned responses
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content_tags.definitions[5]1.0the tagger's words
content_tagssensitized responses
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content_tags.definitions[6]1.0the tagger's words
content_tagsdelay paradigm
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content_tags.definitions[7]1.0the tagger's words
content_tagseyeblinks
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also in: eyeblinks
content_tags.definitions[8]1.0the tagger's words
content_tagsSham surgery
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also in: Sham surgery
content_tags.definitions[9]1.0the tagger's words
content_tagspseudopregnancy
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content_tags.definitions[10]1.0the tagger's words
content_tagsceiling effect
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content_tags.definitions[11]1.0the tagger's words
content_tagsProestrus
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also in: Proestrus
content_tags.definitions[12]the tagger's words
content_tagsestrus
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also in: estrus
content_tags.definitions[13]the tagger's words
content_tagsdiestrus
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also in: diestrus
content_tags.definitions[14]the tagger's words
content_tagssex
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also in: sex
content_tags.variables[1]the tagger's words
content_tagsacquisition of the conditioned eyeblink response
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content_tags.variables[6]the tagger's words
content_tagsanalgesic responses
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content_tags.variables[7]the tagger's words
content_tagsspontaneous blink rate
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content_tags.variables[8]the tagger's words
content_tagsSham surgery
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also in: Sham surgery
content_tags.variables[10]the tagger's words
content_tagsintertrial interval
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content_tags.variables[11]the tagger's words
content_tagsrate of acquisition of the conditioned response
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content_tags.variables[12]1.0the tagger's words
content_tagssex
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also in: sex
content_tags.variables[13]1.0the tagger's words
content_tagsstressor exposure
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content_tags.variables[14]1.0the tagger's words
content_tagsCS intensity
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also in: CS intensity
content_tags.variables[15]1.0the tagger's words
content_tagsspontaneous blink rate
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content_tags.variables[16]1.0the tagger's words
content_tagspaired ( n = 7) or explicitly unpaired ( n = 4) conditioning stimuli
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content_tags.variables[17]1.0the tagger's words
content_tagstailflick response
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content_tags.variables[18]1.0the tagger's words
content_tagsForty-four — male and female rats used in the first sex-by-stress experiment
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content_tags.quantities[0]the tagger's words
content_tags30 shocks (1 s, 1 mA, 60 Hz, 1 per min for 30 min) — the stressor administered to stressed rats 24 h before conditioning
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content_tags.quantities[1]the tagger's words
content_tags300 trials a day for 2 days — the conditioning schedule in the first experiment
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content_tags.quantities[2]the tagger's words
content_tags72% ± 11 versus 37% ± 8% — conditioned responding over the first 20 trials in unstressed females versus unstressed males
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content_tags.quantities[3]the tagger's words
content_tags47% ± 7 — first-20-trial acquisition rate of unstressed females once the CS was lowered to 80 dB, close to the male rate of 37%
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content_tags.quantities[4]the tagger's words
content_tagsF (1, 36) = 14.28; P < 0.001 — the sex-by-stress interaction on acquisition of the conditioned response
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content_tags.quantities[5]the tagger's words
content_tagsF (1, 37) = 3.93; P = 0.05 — the effect of estrogen-receptor blockade on the stress-induced impairment of acquisition
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content_tags.quantities[6]the tagger's words
content_tags20 of 21 — tamoxifen-treated females whose vaginal cytology indicated diestrus and low estrogen
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content_tags.quantities[7]the tagger's words
content_tagsfrom <1 of 10, to 2 of 10 — increase in sensitized responses to the white-noise stimulus produced by ovariectomy alone
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content_tags.quantities[8]the tagger's words
content_tagsF (1, 36) = 14.28; P < 0.001 — the sex-by-stress interaction on acquisition, the paper's central result
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content_tags.quantities[9]1.0the tagger's words
content_tags72% ± 11 vs 37% ± 8% — first-20-trial acquisition, unstressed females against unstressed males
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content_tags.quantities[10]1.0the tagger's words
content_tags47% ± 7 — unstressed female acquisition after the CS was lowered to 80 dB, matched to the male rate
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content_tags.quantities[11]1.0the tagger's words
content_tags30 shocks — the stressor: 1 s, 1 mA, 60 Hz, one per minute for 30 minutes
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content_tags.quantities[12]1.0the tagger's words
content_tags24 h — delay between stressor cessation and conditioning
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content_tags.quantities[13]1.0the tagger's words
content_tags300 trials a day for 2 days — training schedule in the first experiment
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content_tags.quantities[14]1.0the tagger's words
content_tags85-dB, 240-ms — the white noise conditioned stimulus
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content_tags.quantities[15]1.0the tagger's words
content_tags0.7-mA, 80-ms — the periorbital shock unconditioned stimulus
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content_tags.quantities[16]1.0the tagger's words
content_tags20 ± 10 s — intertrial interval
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content_tags.quantities[17]1.0the tagger's words
content_tags80 ms — the latency boundary separating conditioned from sensitized responses
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content_tags.quantities[18]1.0the tagger's words
content_tagsF (1, 34)= 10.42; P < 0.005 — the ovariectomy-by-stress interaction
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content_tags.quantities[19]1.0the tagger's words
content_tagsF (1, 37) = 3.93; P = 0.05 — the tamoxifen-by-stress interaction
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content_tags.quantities[20]1.0the tagger's words
content_tags1.5 mg — daily tamoxifen dose in sesame oil, for 4 days
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content_tags.quantities[21]1.0the tagger's words
content_tags44 male and female — sample in the first experiment
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content_tags.quantities[22]1.0the tagger's words
content_tags37 adult female — sample in the ovariectomy experiment
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content_tags.quantities[23]1.0the tagger's words
content_tags41 adult female — sample in the tamoxifen experiment
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content_tags.quantities[24]1.0the tagger's words
content_tags20 of 21 — tamoxifen-treated females whose cytology indicated diestrus
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content_tags.quantities[25]1.0the tagger's words
content_tags0.3–1.0 kHz, amplified 10,000× — electromyograph filter band and gain
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content_tags.quantities[26]1.0the tagger's words

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