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Menstrual Cycle Phase Influences Cognitive Performance in Women and Modulates Sex Differences: A Combined Longitudinal and Cross-Sectional Study PDF Free Download

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Academic Editor: Paul D. Terry

Received: 2 July 2025

Revised: 1 August 2025

Accepted: 11 August 2025

Published: 15 August 2025

Citation: Sawicka, A.K.; Michalak,

K.M.; Naparło, B.; Bermudo-Gallaguet,

A.; Mataró, M.; Winklewski, P.J.;

Marcinkowska, A.B. Menstrual Cycle

Phase Inﬂuences Cognitive

Performance in Women and

Modulates Sex Differences:

A Combined Longitudinal and

Cross-Sectional Study. Biology 2025,14,

1060. https://doi.org/10.3390/

biology14081060

Licensee MDPI, Basel, Switzerland.

This article is an open access article

distributed under the terms and

conditions of the Creative Commons

Attribution (CC BY) license

(https://creativecommons.org/

licenses/by/4.0/).

Article

Menstrual Cycle Phase Inﬂuences Cognitive Performance in

Women and Modulates Sex Differences: A Combined

Longitudinal and Cross-Sectional Study

Angelika K. Sawicka 1,* , Katarzyna M. Michalak 1,* , Barbara Naparło 1, AdriàBermudo-Gallaguet 2,3,4 ,

Maria Mataró 2,3,4, Pawel J. Winklewski 5,6 and Anna B. Marcinkowska 1,7

1Applied Cognitive Neuroscience Lab, Department of Neurophysiology, Neuropsychology and

Neuroinformatics, Medical University of Gdansk, 80-211 Gdansk, Poland; rabarbara@gumed.edu.pl (B.N.);

anna.marcinkowska@gumed.edu.pl (A.B.M.)

2Departament de Psicologia Clínica i Psicobiologia, Facultat de Psicologia, Universitat de Barcelona (UB),

Passeig de la Vall d’Hebron, 171, 08035 Barcelona, Spain; abermudo@ub.edu (A.B.-G.);

mmataro@ub.edu (M.M.)

Institut de Neurociències, Universitat de Barcelona, Passeig de la Vall d’Hebron, 171, 08035 Barcelona, Spain

4Institut de Recerca Sant Joan de Déu, Santa Rosa 39-57, 08950 Esplugues de Llobregat, Spain

5Department of Neurophysiology, Neuropsychology and Neuroinformatics, Medical University of Gdansk,

80-211 Gdansk, Poland; pawel.winklewski@gumed.edu.pl

6Institute of Health Sciences, Pomeranian University in Slupsk, 76-200 Slupsk, Poland

72nd Department of Radiology, Medical University of Gdansk, 80-211 Gdansk, Poland

*Correspondence: angelika.sawicka@gumed.edu.pl (A.K.S.); k.michalak@gumed.edu.pl (K.M.M.)

Simple Summary

Hormonal ﬂuctuations during the menstrual cycle can impact a woman’s performance on

tasks that require memory, attention, and cognitive processing speed. These changes could

also help explain cognitive differences between women and men. In this study, we tested

71 young adults on a series of cognitive tasks. Women were assessed twice: during the

menstrual phase (low hormone levels) and the pre-ovulatory phase (when oestradiol is

high). Men were tested once. We found that women performed better on memory and

attention tasks just before ovulation. Differences in processing speed between men and

women were observed only during women’s menstrual phase. These differences disap-

peared when oestradiol levels were higher (before ovulation). In men, better performance

was also linked to higher oestradiol and progesterone. Our results suggest that oestradiol

plays an important role in cognitive changes during the menstrual cycle. Recognising hor-

monal variation, especially in oestradiol, may be essential when studying sex differences

in cognition.

Abstract

Sex hormones’ and menstrual cycle’s effects on cognitive performance remain unclear.

This study examined cognitive differences between women across menstrual cycle phases,

sex differences between women and men, and hormone–cognition associations. In total,

71 healthy young adults, aged 20–36 (42 women, 29 men), completed standardised cognitive

tests measuring attention, processing speed, working memory, and visuospatial abilities.

Women were tested twice: during menstrual (low-oestradiol) and pre-ovulatory (high-

oestradiol) phases; men once. Hormone levels (oestradiol, progesterone, testosterone)

were measured in blood samples via electrochemiluminescence immunoassay (ECLIA).

Two analytical strategies were used: (1) within-subject analysis comparing women between

phases, and (2) between-group comparison across three groups—women in menstrual

phase, pre-ovulatory phase, and men. Women performed better during pre-ovulatory

Biology 2025,14, 1060 https://doi.org/10.3390/biology14081060

Biology 2025,14, 1060 2 of 22

versus menstrual phase in working memory (Digit span forward: p= 0.04; Digit span

backwards max: p= 0.02) and attention switching (Trail Making Test B: p= 0.01). Sex

differences in processing speed were observed only during the menstrual phase (Trail

Making Test A: p= 0.03; Stroop B: p= 0.04), but not in the pre-ovulatory phase. Positive

correlations between oestradiol/progesterone and cognitive performance were found in

men, while complex bidirectional relationships emerged in women during the menstrual

phase only. Testosterone showed no signiﬁcant correlations. These ﬁndings highlight

hormonal status effects on cognitive sex differences.

Keywords: menstrual cycle; gonadal steroid hormones; memory short-term; attention; sex

characteristics; oestradiol; follicular phase

1. Introduction

The menstrual cycle, characterised by dramatic ﬂuctuations in sex hormone levels,

provides a natural model for studying hormonal inﬂuence on cognition. The menstrual

cycle begins with the early follicular phase, characterised by low progesterone and oe-

strogen levels. Oestrogen levels rise rapidly in the late follicular phase, showing a nearly

eight-fold increase and a peak one day before ovulation. The luteal phase sees a steady

rise in progesterone levels that peaks in the mid-luteal phase with an 80-fold increase,

accompanied by a second oestrogen peak. Both hormone levels decline during the late

luteal phase, reaching baseline shortly before the onset of menstruation [1,2].

Research shows that steroid hormones, their fluctuations, and their receptors play a

significant role in various brain functions, including regulating socio-sexual behaviour,

neurogenesis, cognitive function, mood, and emotion [

]. oestrogen receptors (ERs)

and progesterone receptors (PRs) are found throughout the brain in regions involved

in cognitive and emotional regulation [

–

]. Through these receptors, sex hormones

influence cognitive function via multiple mechanisms, including the modulation of

neurotransmitter systems, the regulation of synaptic plasticity, and effects on neural

connectivity [6–8].

In young women, evidence suggests that hormonal fluctuations can induce reversible

structural changes in the brain. Research has demonstrated that grey matter volume in

young women exhibits relative increases in the right anterior hippocampus and relative

decreases in the right dorsal basal ganglia during the postmenstrual phase [

]. It has been

proven that oestrogen improves performance in prefrontal cortex-dependent learning

in animal and human studies [

–

]. Related changes were seen in studies of healthy

women showing differential Stroop task performance between phases characterised by

low versus high concentrations of oestradiol and progesterone during the menstrual

cycle [

]. These results suggest that sex-related hormone modulation selectively affects

cognitive function depending on the type of task and that low levels of oestradiol secretion

appear to contribute to a reduction in the level of attention related to the aforementioned

prefrontal cortex. According to research, higher oestrogen levels have a protective effect

on cognitive functioning [

] and positively correlate with processing speed and sustained

attention [

]. Furthermore, oestrogen is involved in memory processes and can also

affect different types of memory, such as episodic memory, working memory [

], and

long-term memory [

]. Additionally, oestradiol may modulate visuospatial functions,

including visuospatial orientation [

] and visuospatial memory [

]. Regarding pro-

gesterone, an fMRI study proved that this hormone modulates limbic and somatomotor

networks, which can improve cognitive function in naturally cycling young women [

Biology 2025,14, 1060 3 of 22

Both oestrogen and progesterone treatments have shown potential cognitive benefits

in women, with progesterone showing better effects on verbal working memory [

Testosterone, on the other hand, activates a distributed cortical network, the ventral pro-

cessing stream, during spatial cognition tasks, and the addition of testosterone improves

spatial cognition in men [

]. According to research, testosterone also protects the brain

against oxidative stress, serum deprivation-induced apoptosis, and soluble amyloid-

) toxicity [

]. Recent research has suggested that testosterone’s effects on cognition

may be particularly important in women, especially in those carrying genetic risk factors

for cognitive decline [

]. This hormone can be converted to oestradiol in the brain

through aromatisation, thereby potentially affecting cognition through both androgen

and oestrogen-dependent mechanisms [

]. Studies have suggested the involvement

of testosterone in spatial abilities and working memory, though its effects may differ

between men and women [24,25].

However, despite numerous studies suggesting that cognitive functions in women vary

depending on the phase of the menstrual cycle and hormone levels, the scientiﬁc literature

remains inconsistent, and several studies have not found signiﬁcant changes [

–

]. These

contradictory ﬁndings may stem from methodological differences, including reliance on

estimated cycle phases rather than quantitative hormonal measurements, variations in

cognitive testing batteries employed, and differences in participant characteristics and

sample sizes.

In summary, steroid hormones, especially oestradiol, may inﬂuence cognitive function

in areas critical for daily functioning and academic achievement, making them particularly

relevant for the study of hormone-dependent changes in cognitive function in young

adult women. However, the exact nature of these relationships within the menstrual cycle

remains unclear, especially regarding their potential impact on sex differences in cognitive

functioning between women and men.

Building on the existing literature, we aimed to investigate three key research ques-

tions. First, we examined whether women’s cognitive functioning changes across the

menstrual cycle phases, focusing on attention, processing speed, short-term and work-

ing memory, and visuospatial abilities. We hypothesised that performance would be

enhanced during the pre-ovulatory phase (high oestradiol) compared to the menstrual

phase (low oestradiol and progesterone), reflecting primarily the facilitating effects of

elevated oestradiol levels, particularly in tasks measuring working memory [

], pro-

cessing speed [

], and attention [

]. Second, we investigated sex differences in cognitive

functioning between young, healthy women and men, comparing men with women in

both menstrual cycle phases to determine whether these differences are modulated by

hormonal status. Here, we expected to find sex differences in information processing

speed and visuospatial abilities, with these differences being dependent on women’s

menstrual cycle phase [

]. Third, we explored associations between sex hormone

levels (oestradiol, progesterone, and testosterone) and cognitive performance in both men

and women, comparing the menstrual phase (lowest oestradiol) with the pre-ovulatory

phase (highest oestradiol). For this aim, we hypothesised that higher oestradiol levels

would be associated with better working memory and attention performance [

progesterone levels would show an association with cognitive performance, in line with

previous research, through underlying neural mechanisms (the limbic and somatomotor

networks) [

], and testosterone levels would demonstrate positive relationships with

spatial abilities and working memory [24,25].

Biology 2025,14, 1060 4 of 22

In this study, we speciﬁcally chose to compare the menstrual phase (days 2–5 after

menstruation onset) and the pre-ovulatory phase (up to 2 days before expected ovulation)

for several methodological and theoretical reasons. These two phases represent the most

distinct hormonal proﬁles within the menstrual cycle, with the menstrual phase charac-

terised by minimal levels of both oestradiol and progesterone, while the pre-ovulatory

phase features a pronounced oestradiol peak with still relatively low progesterone. This

hormonal contrast provides an optimal window to examine oestradiol’s speciﬁc effects on

cognition with minimal confounding inﬂuence from progesterone.

To address these research questions, the study employed two analytical approaches:

(1) a longitudinal analysis including only women, comparing their cognitive performance

across the menstrual and pre-ovulatory phases, and (2) a cross-sectional analysis comparing

men and women at each phase. By combining these two approaches, we provided new

insights into sex differences and hormonal ﬂuctuations within the same examination group.

By measuring hormone levels, we could exclude nonspeciﬁc patients with irregular cycles

or without hormone peaks ﬁtting the normal range for the cycle phase. For methodological

consistency in the latter approach, only data from women’s ﬁrst evaluation sessions were

used compared with men.

2. Materials and Methods

2.1. Ethics Statement

All participants were informed about the procedures, risks, and expected outcomes

before starting the assessment procedure and gave their written informed consent for

participation. The study was conducted under the Declaration of Helsinki. The study

protocol was approved by the Independent Bioethics Commission for Research at the

Medical University of Gdansk (NKBBN/398/2021 and NKBBN/398-14/2023).

2.2. Participants

Recruitment for the study was conducted continuously between December 2022

and November 2023. The participants were recruited through the universities’ methods

of communication, such as mailing lists and advertisements on social media. The qual-

ifications for the study were assessed using an online questionnaire and consultation.

A diverse group of 115 people applied for the study, of whom 104 were accepted for the

study procedure. Inclusion criteria for all participants were as follows: an age range

18–36 years

and being a native Polish speaker. For women, an additional inclusion

criterion was a regular menstrual cycle length defined as 24 to 38 days (as defined by the

International Federation of Gynaecology and Obstetrics (FIGO) in 2018), with a variation

in duration between cycles of no more than 8 days [

]. The non-inclusion criteria were

as follows: any neurological or mental disorder, current use of psychiatric medications,

chronic diseases (such as diabetes), irregular menstruation in women, endometriosis or

polycystic ovary syndrome, current or recent (within the past six months) use of hormonal

contraceptives, current or past hormone therapy, current pregnancy, and postpartum

period or breastfeeding within one year prior to the study. In addition, women who

showed inconsistency between their declared cycle phase and measured hormone levels

were excluded from the statistical analysis. Ultimately, 71 young, healthy adults were

included in the statistical analyses—42 women (mean

age = 23.64 ±3.53

) and 29 men

(mean age = 24.1 ±3.46). All participants had comparable education levels (mean years

of education = 16.02

2.48) and body mass index (BMI;

mean = 23.09 ±3.72

), ensuring a

high degree of group homogeneity (Figure 1).

Biology 2025,14, 1060 5 of 22

Figure 1. Trial ﬂow diagram. Note: The diagram illustrates the recruitment, screening, and selection

process for all participants in the study. The ﬁnal sample, consisting of 71 participants, comprised

42 women and 29 men.

2.3. Study Design

To address our research questions, two main analytical approaches were used

(Figure 2).

(1) Longitudinal analysis (within women): To compare women’s cognitive functioning

between the menstrual and pre-ovulatory phases, the Wilcoxon signed-rank test with a

calculated effect size was used for dependent groups.

(2) Cross-sectional analysis (between men and women): To compare cognitive per-

formance between men and women, participants were divided into three independent

groups: men (M; n = 29), women in the menstrual phase (W1; n = 26), and women in the

pre-ovulatory phase (W2; n = 16). The groups of women (W1 and W2) were established

based on the phase in which they underwent their ﬁrst neuropsychological assessment to

ensure methodological homogeneity and avoid practice effects when comparing with men,

who were tested only once. The Kruskal–Wallis test, followed by post hoc Mann–Whitney

U tests, was used to evaluate differences between these three groups.

Biology 2025,14, 1060 6 of 22

Figure 2. Study design overview: Two-stage analytical approach. Note: Stage 1—Longitudinal

Analysis (within-subject comparison): Women (n = 42) were assessed at two time points within the

same menstrual cycle (during the menstrual phase (low oestradiol) and pre-ovulatory phase (high

oestradiol)), allowing for within-subject comparisons of cognitive performance across hormonal

states. Stage 2—Cross-sectional Analysis (between subject comparison): For sex difference analyses,

participants were reorganised into three independent groups based on the timing of the ﬁrst cognitive

assessment: Men (M; n = 29) who underwent a single assessment, Women (W1; n = 16) whose ﬁrst

assessment occurred during the menstrual phase, and Women (W2; n = 26) whose ﬁrst assessment

occurred during the pre-ovulatory phase. This approach enabled between-group comparisons

while controlling for practice effects by using only ﬁrst-session data from women when comparing

with men.

2.4. Assessment Timing

To precisely determine assessment periods coinciding with speciﬁc hormonal states,

we implemented a structured menstrual cycle tracking protocol. Female participants

completed a reproductive history questionnaire documenting cycle regularity, average

cycle length (calculated from the preceding three menstrual cycles), and the onset date of

their most recent menstruation. All women included in the ﬁnal analysis exhibited regular

menstrual cycles (ranging between 24 and 38 days) [29].

Assessments were scheduled during two distinct cycle phases characterised by maxi-

mally differentiated oestradiol proﬁles: the menstrual phase (days 2–5 post-menstruation

onset), corresponding to minimal oestradiol and progesterone concentrations; and the

pre-ovulatory phase (0–2 days pre-ovulation), characterised by elevated oestradiol with

still relatively low progesterone levels [

]. Expected ovulation dates were calculated using

the reverse counting method (subtracting 14 days from the anticipated next menstruation)

and veriﬁed through conﬁrmation of subsequent menstrual onset.

To control for potential practice effects while ensuring within-subject comparisons,

we employed a randomised crossover design in which all participants completed two

assessments—one during the menstrual phase and one during the pre-ovulatory phase.

Participants were randomly assigned to begin the study in either cycle phase, with their

second assessment scheduled in the alternate phase. This approach enabled us to follow

each woman across both hormonal conditions while controlling for potential order effects.

Following participant attrition and exclusion of cases with hormonal proﬁles inconsistent

Biology 2025,14, 1060 7 of 22

with expected phase values, the ﬁnal analytical sample included 42 women (26 who began

in the menstrual phase and 16 who began in the pre-ovulatory phase). This design supports

robust within-subject comparisons while mitigating confounding practice effects.

2.5. Hormone Measurements

Before every cognitive examination, blood samples were collected from the partici-

pants to determine their hormone levels of progesterone, oestradiol, and testosterone. For

female participants, blood samples and cognitive tests were conducted twice, timed to

capture hormonal ﬂuctuations across the menstrual cycle (once during the menstrual phase

and once during the pre-ovulatory phase). For male participants, blood sampling and

cognitive testing were performed once.

Blood tests were performed in the fasting state and collected in the morning, speciﬁ-

cally between 7:00 and 10:00 a.m. The samples were collected and analysed by a certiﬁed

commercial laboratory using the electrochemiluminescence immunoassay (ECLIA) method

and Cobas Pro device.

The analytical performance characteristics for the assays were as follows: for oestradiol,

the limit of detection (LoD) was 18.4 pmol/L (5 pg/mL), the limit of quantiﬁcation (LoQ)

was 91.8 pmol/L (25 pg/mL), intra-assay CV ranged from 1.2 to 5.4%, and inter-assay

CV ranged from 1.9 to 7.1%. For progesterone, the LoD was 0.159 nmol/L (0.05 ng/mL),

the LoQ was 0.636 nmol/L (0.2 ng/mL), intra-assay CV ranged from 1.3 to 3.2%, and

inter-assay CV ranged from 3.7 to 5.5%. For testosterone, the LoD was 0.087 nmol/L

(

0.025 ng/mL

), the LoQ was 0.416 nmol/L (0.120 ng/mL), intra-assay CV ranged from 1.1

to 3.0%, and inter-assay CV ranged from 2.3 to 5.1%. Precision was determined according

to CLSI (Clinical and Laboratory Standards Institute) protocol EP05-A3.

2.6. Cognitive Tests

Cognitive testing was conducted between 8:00 a.m. and 12:00 p.m. to ensure con-

sistency in timing and to control for potential circadian inﬂuences. During the neuropsy-

chological assessment, the participants completed six tests in a ﬁxed order, as described

below. The total duration of the cognitive assessment was 45–60 min, depending on each

individual’s performance speed. Short breaks (2–3 min) were provided between the tests

when requested by the participants to minimise fatigue effects.

The Stroop test from the Delis–Kaplan Executive Function System (D-KEFS) bat-

tery [

] measures rapid processing, attentional selectivity, inhibitory processing, and

cognitive ﬂexibility. It is a neuropsychological test widely used to assess the ability to

inhibit cognitive interference, which occurs when the processing of one stimulus feature

prevents the simultaneous processing of a second stimulus feature. This test contained

four conditions, each preceded by a short trial, and the time taken to complete each was

measured. The ﬁrst task (A) was to say the colour of the squares (blue, red, and green), the

second (B) was to read words written in black ink as quickly as possible, the next (C) was

to say the colour of the ink in which the words were written (written colour names were

incongruent with the ink colour), and the ﬁnal task (D) was to read a word written in an

ink colour incongruent with the name of the colour if written without a frame, or to say the

name of the colour according to the word that was written if the word was in a frame. All

the tasks were presented on white sheets of A4 paper lying horizontally. Word reading and

colour naming are measures of processing speed, while colour–word inhibition measures

executive functions [

]. In this test, we measured the time taken to complete each task and

the interference between each subtest.

Digit span forward and backwards repetition from the Wechsler Adult Intelligence

Scale [

] measures auditory short-term and working memory. The participants repeated

Biology 2025,14, 1060 8 of 22

an increasing number of random digits forward and then backwards in the order given

by the researcher. Each correctly repeated series was followed by another series plus an

additional digit. If the participant failed the ﬁrst attempt, the subject was given a second

chance with a different set of numbers of the same length. If the subject failed the second

attempt, the test was terminated. In this test, we measured the number of points the subject

scored and the number of items correctly recalled in the longest sequence.

The trail making test (TMT) parts A and B [

] measure visual processing speed,

visual perceptual ability, working memory, task-switching ability, and executive control.

In part A, the participants had to match the following numbers on an A4 sheet of paper;

in part B, the numbers and letters alternated in alphabetical order. Before the actual test,

the participants completed a trial task. The time taken to complete the task was measured.

Another indicator of working memory performance was the ratio of the time taken to

complete part A to part B.

The Corsi block-tapping test [

] measures spatial short-term and working memory.

The test requires the maintenance of a visuospatial pattern and sequence of movements [

Corsi’s original apparatus consisted of a series of nine blocks arranged irregularly on a

board. The blocks were tapped by the experimenter in random sequences of increasing

length. There were two subtests: the forward and the backwards subtest. Immediately after

each tapped sequence, the participant attempted to reproduce it, progressing until they

failed to correctly reproduce two sequences of the same length [

]. As the test progressed,

the number of blocks increased. The score was assessed by the maximum number the

participant could reproduce correctly in the forward and backwards directions. The total

score forward (TSF) and total score backwards (TSB) indices gave the number of examples

performed correctly multiplied by the length of the sequence reproduced correctly.

The visual pattern test (VPT) [

] measures short-term non-verbal memory and mem-

ory for item sequences. There were two parallel sets of patterns, set A and set B, which

formed two parallel forms of the test, version A and version B, respectively. The grids

ranged in size from the smallest, a 2

2 matrix (with two ﬁlled cells), to the largest, a

5×6 matrix

(with 15 ﬁlled cells), with the complexity increasing progressively by adding

two additional cells to the previous grid. Therefore (assuming the simplest pattern can be

reproduced), the subject received a score ranging from 2 to 15 [

]. During the test, the

participants were shown patterns of black squares for three seconds and asked to reproduce

them from memory. The test was stopped when the participant incorrectly reproduced

three boards with the same number of cells. The result of the test was the maximum number

of elements that the participant was able to recall and the average number of the last three

examples that the participant got right.

The visual perceptual skills–subtests memory and sequence [

] measure short-term

visual recognition. Due to the young, healthy group of participants, the ﬁrst six items in

each subtest were omitted—the items were too easy to recognise and did not differentiate.

The next 10 items were shown for three seconds, and the last six for 5 s. After viewing

each ﬁgure or sequence of elements, the participant was expected to identify and select the

correct one from other similar options. A maximum of 18 points could be scored. During the

test, the participant did not receive any feedback on whether they were speaking correctly.

2.7. Statistical Analysis

Statistical analyses were performed using the Statistical Package for Social Sciences

(SPSS) version 29 (IBM Corp., Armonk, NY, USA) and GraphPad Prism 8 (GraphPad

Software, San Diego, CA, USA).First, Shapiro–Wilk’s test was used to check for the normal

distribution of the variables. As the cognitive results and hormonal concentrations were

not normally distributed, non-parametric tests were performed.

Biology 2025,14, 1060 9 of 22

For the longitudinal part of the study, women’s cognitive performance in the

two phases of the menstrual cycle was compared using the Wilcoxon signed-rank test

with a calculated effect size. For the cross-sectional part of the study, women’s cognitive

performance in the two phases of the menstrual cycle was compared to men’s using the

Kruskal–Wallis test with a post hoc Mann–Whitney U test.

Correlations between the changes in hormone levels and cognitive performance were

calculated using partial correlation tests adjusted by age. To assess the relationship be-

tween hormone levels and cognitive performance, we matched each participant’s hormone

concentrations to their performance on speciﬁc cognitive tasks completed on the same day.

Partial correlations were conducted for all samples together and separately for each group

(M, W1, and W2). A p-value < 0.05 was considered statistically signiﬁcant.

3. Results

3.1. Hormonal Data

Women participating in the study were characterised by a regular menstrual cycle,

with a duration in our group ranging from 25 to 35 days (Table 1). Oestradiol levels were

signiﬁcantly higher in the pre-ovulatory phase than in the menstrual phase of the cycle

(

T = 5.65

;p< 0.001;

r = 0.6

), and progesterone levels were likewise higher (T = 2.48; p= 0.01;

r = 0.3

) (Figure 3). Hormonal status was as expected for the healthy women in both phases

of the menstrual cycle (Table 2). We also investigated hormone levels in men during the

study (Table 2).

Table 1. Presentation of the information on women’s menstrual cycles.

Women (n = 42)

Variable M (SD) Min Value Max Value

Length of the menstrual cycle (days) 30.05 (2.17) 25 35

Duration of the menstrual phase (days)

5.52 (0.86) 4 7

Abbreviations: n, number of participants in a given group; M, mean; SD, standard deviation; Min value, minimum

value in a given set; Max value, maximum value in a given set.

Figure 3. Changes in progesterone and oestradiol levels in women (n = 42) during two menstrual

cycle phases. Note: Data are presented as the mean

SE and were analysed using the Wilcoxon

signed-rank test. Signiﬁcant differences are denoted by *** p< 0.001 and * p< 0.05. Progesterone is

marked in coral, while oestradiol is marked in violet.

Biology 2025,14, 1060 10 of 22

Table 2. Concentrations of hormones in groups of women and men.

Group/Phase

Testosterone

(nmol/mL)

M (SD)

Progesterone

(ng/mL)

M (SD)

Oestradiol

(pg/mL)

M (SD)

Women (n = 42)

Menstrual phase 1.32 (0.45) 0.37 (0.2) 30.86 (16.74)

Pre-ovulatory phase 1.77 (0.58) 2.06 (3.92) 163.98 (115.85)

Men (n = 29)

18.95 (6.07) 0.35 (0.19) 24.79 (8.09)

Abbreviations: n, number of participants in a given group; M, mean; SD, standard deviation.

3.2. Changes in Cognitive Performance Between Women in the Menstrual and

Pre-Ovulatory Phases

The longitudinal analysis revealed signiﬁcant improvements in cognitive performance

among women during the pre-ovulatory phase compared to their performance in the

menstrual phase. Speciﬁcally, women demonstrated enhanced working memory, with

better results in the digit span forward (T = 2.06, p= 0.04, r = 0.22), digit span forward max

(T = 2.61, p= 0.01, r = 0.28), and digit span backwards max (T = 2.32, p= 0.02, r = 0.25) tests.

Performance in attention switching also improved, as indicated by a faster completion

time for the Trail Making Test B (T = 2.61, p= 0.01, r = 0.28). For all statistically signiﬁcant

results, the effect size ranged from 0.2 to 0.3, indicating a small-to-medium effect size. No

signiﬁcant changes were observed for other cognitive measures. Detailed results for all

within-woman comparisons are presented in Table 3.

Table 3. Changes in the cognitive performance between women in the menstrual and pre-ovulatory

phases of the cycle.

Variables Group N Mean SD Median Mean

Rank

Sum of

Ranks Tpr

Digit span

forward

W_M 42 7.33 2.54 7 Negative 133.5 2.06 0.04 * 0.22

W_PO 42 8.0 2.06 8 Positive 331.5

Digit span

forward max

W_M 42 6.24 1.38 6 Negative 93.0 2.61 0.01 * 0.28

W_PO 42 6.74 1.27 7 Positive 313.0

Digit span

backward

W_M 42 7.0 2.35 7 Negative 167.5 1.84 0.07 0.20

W_PO 42 7.48 2.08 7 Positive 360.5

Digit span

backward max

W_M 42 4.98 1.3 5 Negative 96.0 2.32 0.02 * 0.25

W_PO 42 5.43 1.21 5 Positive 282.0

TMT A time (s) W_M 42 22.83 7.41 21.45 Negative 525.5 1.55 0.12 0.17

W_PO 40 21.68 7.29 20.13 Positive 294.50

TMT B time (s) W_M 42 47.47 14.38 47.23 Negative 604.00 2.61 0.01 * 0.28

W_PO 40 41.57 9.74 41.63 Positive 216.00

TMT B/A time (s) W_M 42 2.15 0.56 2.11 Negative 489.00 1.06 0.29 0.12

W_PO 40 2.02 0.57 1.89 Positive 331.00

Corsi block span

forward

W_M 42 6.33 1.07 6 Negative 228.5 0.98 0.33 0.11

W_PO 42 6.17 1.17 6 Positive 149.5

Biology 2025,14, 1060 11 of 22

Table 3. Cont.

Variables Group N Mean SD Median Mean

Rank

Sum of

Ranks Tpr

Corsi TSF W_M 42 61.9 21.01 60 Negative 409.0 0.87 0.39 0.09

W_PO 42 58.88 21.76 54 Positive 294.0

Corsi block span

backward

W_M 42 6.60 1.29 6.00 Negative 153.00 0.27 0.79 0.03

W_PO 42 6.57 0.80 6.00 Positive 172.00

Corsi TSB W_M 42 62.10 17.23 60.00 Negative 204.50 1.81 0.07 0.20

W_PO 42 67.05 17.71 60.00 Positive 425.50

VPT max W_M 41 10.32 1.86 10 Negative 172.0 1.52 0.13 0.17

W_PO 42 10.76 1.86 11 Positive 324.0

VPT mean W_M 41 9.76 1.68 10.30 Negative 202.50 1.85 0.07 0.20

W_PO 42 10.18 1.76 10.00 Positive 427.50

VMT Vis Mem W_M 41 16.22 1.26 16.00 Negative 221.50 0.53 0.60 0.06

W_PO 40 16.38 1.41 17.00 Positive 274.50

VMT Seq Mem W_M 41 14.61 1.52 15.00 Negative 163.50 1.91 0.06 0.21

W_PO 40 15.28 1.63 15.00 Positive 364.50

Stroop A time (s) W_M 42 28.28 4.67 27.92 Negative 517.5 0.83 0.41 0.09

W_PO 42 27.85 4.1 26.45 Positive 385.5

Stroop B time (s) W_M 42 22.89 3.50 22.16 Negative 477.50 0.33 0.75 0.04

W_PO 42 22.48 2.42 22.13 Positive 425.50

Stroop C time (s) W_M 42 44.45 9.89 44.75 Negative 606.00 1.93 0.05 0.21

W_PO 42 42.21 8.03 41.53 Positive 297.00

Stroop D time (s) W_M 42 49.10 9.61 48.65 Negative 540.00 1.11 0.27 0.12

W_PO 42 47.69 9.61 47.74 Positive 363.00

Stroop

interference

W_M 42 21.56 7.8 21.44 Negative 598.0 1.83 0.07 0.20

W_PO 42 19.72 7.69 19.79 Positive 305.00

Stroop

interference a

W_M 42 16.17 7.50 13.62 Negative 596.00 1.81 0.07 0.20

W_PO 42 14.35 6.08 13.70 Positive 307.00

Stroop

interference b

W_M 42 −2.06 8.37 −2.65 Negative 552.50 1.26 0.21 0.14

W_PO 42 −2.65 7.84 −3.04 Positive 350.50

Stroop

interference c

W_M 42 4.65 7.94 4.65 Negative 429.00 0.28 0.78 0.03

W_PO 42 5.48 8.44 5.21 Positive 474.00

Note: Values marked with an asterisk (*) indicate the level of statistical signiﬁcance (p< 0.05). Abbreviations: W_M,

women in the menstruation phase; W_PO, women in the pre-ovulatory phase; N, the number of participants

in a given group.; SD, standard deviation; T, the test statistic for the Wilcoxon signed-rank test; p, the p-value,

representing the probability of obtaining the observed results under the null hypothesis; p< 0.05, indicates

statistical signiﬁcance, meaning there is less than a 5% probability that the observed effect occurred by chance; r,

the effect size; DSF, digit span forward; DSB, digit span backward; TMT A, Trail Making Test A; TMT B, Trail

Making Test B; TMT B/A, Trail Making Test B/A Ratio; CORSI TSF, Corsi Total Score Forward; CORSI TSB, Corsi

Total Score Backward; VPT Max, Visuospatial Test Maximum, the highest level of performance achieved in a

visuospatial test; VPT Mean, Visuospatial Test Mean, the average score in a visuospatial test, reﬂects overall

performance; VMT Vis Mem, Visual Memory Task—Visual Memory; VMT Seq Mem, Visual Memory Task—

Sequential Memory. Stroop interference, the difference between the times taken to complete Stroop tests C and B

(Stroop C

−

Stroop B); Stroop interference a, the difference between the times taken to complete Stroop tests C

and A (Stroop C

−

Stroop A); Stroop interference b, difference between the times taken to complete Stroop test

D and the sum of the times taken to complete Stroop tests A and B (Stroop D

−

(Stroop A + Stroop B); Stroop

interference c, difference between the times taken to complete Stroop tests D and C (Stroop D −Stroop C).

Biology 2025,14, 1060 12 of 22

3.3. Differences in Cognitive Performance Between Men and Women in Two Phases of the

Menstrual Cycle

The cross-sectional analysis revealed signiﬁcant, phase-dependent sex differences

in cognitive processing speed. An overall comparison between men (M), women in the

menstrual phase (W1), and women in the pre-ovulatory phase (W2) showed signiﬁcant

group differences in the Trail Making Test A (H = 6.77, p= 0.03) and the Stroop B test

(H = 6.60, p= 0.04).

Post hoc tests speciﬁed that these differences were driven solely by the comparison

between men and women in their menstrual phase (W1), where men were signiﬁcantly

faster on both the TMT A (p= 0.04) and Stroop B (p= 0.04). Crucially, as illustrated in

Figure 4, these sex differences disappeared when women were in their high-oestradiol,

pre-ovulatory phase (W2). No signiﬁcant differences between the three groups were found

in any other cognitive tests. Full comparative results are shown in Table 4.

Figure 4. Changes in performance time in the TMT A and the Stroop test in task B between men and

women in two cycle phases. Note: Signiﬁcant differences are denoted by * p< 0.05; Abbreviations: M,

men; W1, women in the menstruation phase; W2, women in the pre-ovulatory phase.

Table 4. Differences in cognitive performance between men and women in the two phases of the

menstrual cycle.

Cognitive Test Group Statistics

N Mean Rank Median IQR KW Statistic p

Digit span forward

W1 26 30.58 7 2

2.96 0.23

W2 16 40.22 8 4

M 29 38.53 8 4

Digit span forward max

W1 26 30.88 6 2

2.67 0.26

W2 16 39.47 6.5 2

M 29 38.67 7 2

Biology 2025,14, 1060 13 of 22

Table 4. Cont.

Cognitive Test Group Statistics

N Mean Rank Median IQR KW Statistic p

Digit span backward

W1 26 31.27 7 3

2.21 0.33

W2 16 38.25 8 3

M 29 39.00 8 4

Digit span backward max

W1 26 30.96 5 2

2.99 0.22

W2 16 36.38 5.5 2

M 29 40.31 6 3

TMT A time (s)

W1 26 43.08 22.5 11.26

6.77 0.03 *

W2 14 30.50 19.31 9.32

M 29 29.93 19.02 6.71

TMT B time (s)

W1 26 37.27 47.75 16.76

0.54 0.76

W2 14 34.07 47.91 15.19

M 29 33.41 44.55 17.78

TMT B/A time (s)

W1 26 30.88 1.89 0.56

1.97 0.37

W2 14 35.43 2.16 1.12

M 29 38.48 2.06 1.21

Corsi block span forward

W1 26 37.12 6 2

0.15 0.93

W2 16 35.97 6 3

M 29 35.02 6 2

Corsi TSF

W1 26 36.58 54 32

0.22 0.90

W2 16 37.44 57 50

M 29 34.69 54 30

Corsi block span backward

W1 26 32.79 6 1

2.27 0.32

W2 16 42.00 7 2

M 29 35.57 6 1

Corsi TSB

W1 26 29.87 57 12

4.37 0.11

W2 16 42.88 66.5 31

M 29 37.71 60 23

Biology 2025,14, 1060 14 of 22

Table 4. Cont.

Cognitive Test Group Statistics

N Mean Rank Median IQR KW Statistic p

VPT max

W1 26 34.62 11 3

1.03 0.60

W2 16 40.53 11 2

M 29 34.74 10 3

VPT mean

W1 26 34.60 10.3 3.07

0.56 0.76

W2 16 39.31 10.15 2.6

M 29 35.43 9.67 2.16

VMT Vis Mem

W1 26 33.87 16 2

0.80 0.67

W2 14 32.25 16 2

M 29 37.34 16 1

VMT Seq Mem

W1 26 33.81 14.5 3

0.40 0.82

W2 14 33.57 14.5 3

M 29 36.76 15.00 2

Stroop A time (s)

W1 26 39.69 28.88 6.8

1.35 0.51

W2 16 33.06 28.18 7.51

M 29 34.31 28.44 4.86

Stroop B time (s)

W1 26 43.37 23.58 3.47

6.60 0.04 *

W2 14 36.59 22.4 2.86

M 29 29.07 21.25 3.75

Stroop C time (s)

W1 26 37.96 45.35 13.23

0.38 0.83

W2 16 34.38 46.27 15.17

M 29 35.14 44.00 9.85

Stroop D time (s)

W1 26 36.38 52.70 13.76

0.35 0.84

W2 16 33.38 49.28 13.6

M 29 37.10 52.09 9.84

Stroop interference

W1 26 35.92 22.37 13.95

0.45 0.80

W2 16 33.28 23.09 14.45

M 29 37.57 23.68 9.99

Biology 2025,14, 1060 15 of 22

Table 4. Cont.

Cognitive Test Group Statistics

N Mean Rank Median IQR KW Statistic p

Stroop interference a

W1 26 36.50 14.11 12.8

0.17 0.92

W2 16 34.13 15.54 10.59

M 29 36.59 15.61 8.71

Stroop interference b

W1 26 32.38 −2.82 15.18

2.44 0.30

W2 16 33.59 0.13 12.51

M 29 40.57 1.34 9.19

Stroop interference c

W1 26 32.08 4.30 12.68

1.49 0.47

W2 16 37.81 6.96 9.55

M 29 38.52 7.28 9.59

Note: Values marked with an asterisk (*) indicate the level of statistical signiﬁcance (p< 0.05). Abbreviations:

W_1, women in the menstruation phase; W_2, women in the pre-ovulatory phase; M, men; N, the number of

participants in a given group; IQR, Interquartile Range—a measure of statistical dispersion, representing the

range between the ﬁrst and third quartiles (Q1–Q3); KW Statistic, Kruskal–Wallis Test Statistic; p, the p-value,

representing the probability of obtaining the observed results under the null hypothesis; p< 0.05, indicates

statistical signiﬁcance, meaning there is less than a 5% probability that the observed effect occurred by chance;

DSF, digit span forward; DSB, digit span backward; TMT A, Trail Making Test A; TMT B, Trail Making Test B;

TMT B/A, Trail Making Test B/A Ratio; CORSI TSF, Corsi Total Score Forward; CORSI TSB, Corsi Total Score

Backward; VPT Max, Visuospatial Test Maximum, the highest level of performance achieved in a visuospatial

test; VPT Mean, Visuospatial Test Mean, the average score in a visuospatial test, reﬂecting overall performance;

VMT Vis Mem, Visual Memory Task—Visual Memory; VMT Seq Mem, Visual Memory Task—Sequential Memory.

Stroop interference, the difference between the times taken to complete Stroop tests C and B (Stroop C

−

Stroop

B); Stroop interference a, the difference between the times taken to complete Stroop tests C and A (Stroop C

−

Stroop A); Stroop interference b, difference between the times taken to complete Stroop test D and the sum of the

times taken to complete Stroop tests A and B (Stroop D

−

(Stroop A + Stroop B); Stroop interference c, difference

between the times taken to complete Stroop tests D and C (Stroop D −Stroop C).

3.4. Correlation Between Hormone Concentration and Cognitive Function

Within group W1 (the low-oestradiol phase), a relatively higher level of oestradiol was

related to better performance in the Stroop interference c (cor. 0.509; p= 0.009). At the same

time, an elevated oestradiol level was negatively correlated with the time score in the TMT

A test (cor. −0.513; p= 0.005) in the M group.

In group W1, the higher level of progesterone was negatively related to the results in

the digit span backwards test (cor.

−

0.407; p= 0.043) and Stroop interference c (cor.

−

0.442;

p= 0.027). Meanwhile, in the M group, progesterone levels were positively correlated with

the results in the Corsi block span forward (cor. 0.366; p= 0.055) and Corsi TSF (cor. 0.396;

p= 0.037) tests.

Testosterone levels did not correlate with any cognitive test scores. No correlations

were observed in the W2 group or when correlating all groups together.

4. Discussion

There are three main ﬁndings of the study. The ﬁrst conclusion was that women’s

cognitive functioning differs according to their cycle phase. We found better short-term

memory capacity, working memory for auditory material, and attention during the high-

oestradiol phase compared to the low-oestradiol phase in a group of the same women.

In our study, we speciﬁcally investigated the predominant effect of oestradiol on

cognitive function by conducting measurements during both menstruation (low oestradiol)

Biology 2025,14, 1060 16 of 22

and the pre-ovulatory phase (high oestradiol with minimal progesterone inﬂuence). This

methodological approach differs from most of the available literature, which compares

menstrual and luteal phases [

–

], when both oestradiol and progesterone levels are

elevated. Such methodological differences between studies create challenges in directly

comparing research ﬁndings. Nevertheless, based on the available literature, we see

consistency between our results and data from the literature, where young women with

higher oestradiol levels showed better performance in working memory [

]. In the study

by Rosenberg and Park [

], similar to our ﬁndings, performing tasks during the high-

oestradiol phase was associated with improved verbal working memory, but there was no

noticeable effect on spatial tasks. However, the small number of participants and the fact

that the cycle phase was estimated in the Rosenberg and Park [

] study should be taken

into account. Contrary to our ﬁndings, previous research (comparing women in four cycle

phases) demonstrated enhanced visuospatial memory during the pre-ovulatory phase [

These discrepant results may reﬂect methodological differences in visuospatial assessment,

as the cited study employed location-based tasks while our battery included sequential

spatial memory (Corsi block-tapping test) and pattern recognition (visual pattern test),

suggesting that cycle effects may be task-speciﬁc within the visuospatial domain.

Our ﬁndings indicating the inﬂuence of menstrual cycle phases on cognitive functions

contrast with the study by Leeners et al. [

], who found no consistent associations be-

tween sex hormone levels and attention, working memory, and cognitive control in two

consecutive menstrual cycles in four cycle phases. This methodologically rigorous study

highlighted the problem of false positive results in this ﬁeld, but several factors can explain

the differences in our observations. First, we used a more extended battery of cognitive

tests (in the cited study, these were the Cognitive Bias Test, Divided Attention Bimodal

Task, and Corsi—in which, as in our study, they did not observe statistically signiﬁcant

changes). Second, our study focused exclusively on healthy young women. In contrast,

approximately 34% of the sample in Leeners’ study consisted of women with endocrine

disorders (endometriosis, PCOS), which may have inﬂuenced the results. Third, although

authors paid particular attention to practice effects as a potential source of false results,

we randomised the ﬁrst assessment phase in our study, which may have controlled for

this confound more effectively. It is also worth noting that a later study by Leeners and

colleagues [

], using an ovarian stimulation model for infertility treatment, also found

no association between very high oestradiol levels and cognitive function, suggesting

that even very high levels of this hormone do not affect cognitive function directly and

unambiguously. However, it should be emphasised that the model used in the 2021 study

differs from the natural hormonal ﬂuctuations in the menstrual cycle, where changes occur

not only in oestradiol but also in progesterone and other hormones in a strictly deﬁned time

pattern. Nevertheless, the cited study is an important reminder of the need for cautious

interpretation of results in studies on the effects of hormones on cognitive function. It

highlights the value of replicating results across menstrual cycles—an aspect that should

be considered in future studies.

To better understand the observed changes, as well as the discrepancies between stud-

ies focusing on cognitive tests themselves, it is worth taking a closer look at neuroimaging

studies. Neuroimaging studies have demonstrated that oestradiol enhances hippocampal

activation during the pre-ovulatory phase of the menstrual cycle in both verbal and spatial

navigation tasks [9,47].

Oestradiol enhances glutamatergic neurotransmission and reduces GABAergic neuro-

transmission, creating an overall excitatory effect in the brain [

]. This increased neuronal

excitability may explain oestradiol’s role in boosting neural activity during cognitive tasks

in high-hormone phases of the cycle, such as the pre-ovulatory phase [

]. The enhance-

Biology 2025,14, 1060 17 of 22

ment of glutamatergic transmission and the reduction in GABAergic inhibition under the

inﬂuence of oestradiol increases neuronal excitability, facilitating rapid and effective data

processing necessary for maintaining concentration and manipulating information in work-

ing memory [

], which we observed in our study. Furthermore, oestradiol increases the

dendritic spine density in the hippocampus [

], which may improve memory functions,

including working memory. Studies also indicate that oestrogen affects the function of

the dopaminergic system, which plays a key role in cognitive processes such as working

memory and executive function. Higher levels of oestradiol may improve working mem-

ory performance by increasing the efﬁciency of information processing in the prefrontal

cortex [50].

Our second key ﬁnding showed that sex differences in information processing speed

and executive functioning between men and women were observed only when women

were in their low-oestradiol (menstrual) phase. This phase-dependent effect was partic-

ularly evident in information processing speed (TMT A time and Stroop B time). These

differences notably disappeared when women were tested during their pre-ovulatory

phase, suggesting that hormonal status plays a role in modulating cognitive sex differences.

The literature presents inconsistent results regarding sex differences in attention

[51–54]

The reason for this lack of clarity is that many studies investigating the cognitive differences

between the sexes do not consider the hormonal changes that occur during the menstrual

cycle and their impact on the results obtained. Recent neuroimaging evidence has provided

insight into these hormone-dependent effects. Pletzer et al. [

] have shown that oestradiol

increases hippocampal activation during the pre-ovulatory phase, which may facilitate

information processing and cognitive performance. This is in line with our observation

of reduced sex differences in the pre-ovulatory phase, suggesting that elevated oestradiol

levels may have a compensatory function in female cognitive performance.

Furthermore, our ﬁndings complement previous research on sustained attention,

where Pletzer et al. [

] observed cycle-dependent variations in attention. While their

study focused on the luteal phase, showing slower response times in women compared

to men during high progesterone levels, our results extend these observations by demon-

strating that sex differences are particularly pronounced during the low-oestradiol phase.

These ﬁndings collectively suggest that both oestradiol and progesterone play distinct

roles in modulating cognitive performance, with oestradiol potentially serving a protec-

tive or enhancing function that may help eliminate baseline sex differences in cognitive

processing speed.

What is concerning is the lack of differences in the visuospatial tests in our study

between men and women. The literature suggests male predominance in visuospatial

tasks. This advantage appears to be domain-speciﬁc, primarily documented in mental

rotation [

] and visual motion processing tasks [

]. Our study’s absence of sex-related

differences in visuospatial functions may be attributed to our test selection. Our battery

included measures of visuospatial capacity and pattern retrieval (visual pattern test; VPT)

and visuospatial sequential working memory (Corsi block-tapping test) rather than tasks

involving mental rotation or motion processing. This methodological distinction may

explain why our ﬁndings diverge from the commonly reported male advantage in speciﬁc

visuospatial domains.

Our third ﬁnding has revealed complex, gender-speciﬁc associations between sex

hormone levels and cognitive functions, but only during the low oestradiol phase in women.

In men, oestradiol levels positively correlated with processing speed, while progesterone

showed associations with enhanced spatial memory capacity. However, during the low

oestradiol phase, the relationship between hormones and cognition appeared more nuanced

in women. Oestradiol demonstrated a signiﬁcant negative relationship with selective

Biology 2025,14, 1060 18 of 22

attention (Stroop interference), while progesterone showed an inverse pattern, correlating

positively with selective attention but negatively with auditory working memory.

These seemingly contradictory ﬁndings can be understood through the underlying

neurobiological mechanisms. Pletzer et al. [

] demonstrated that oestradiol and proges-

terone exert opposing effects on neurotransmitter systems: oestradiol enhances glutamater-

gic transmission while reducing GABAergic neurotransmission, whereas progesterone

produces the opposite effect. This antagonistic relationship between these hormones at the

neurotransmitter level may explain our observed differential effects on cognitive function.

During the early follicular phase, when both hormones are at their lowest levels, the ab-

sence of oestradiol’s stimulating effect on glutamatergic transmission may contribute to

decreased performance in certain cognitive domains. Conversely, progesterone’s enhance-

ment of GABAergic inhibition could potentially impair performance through increased

neural inhibition [6].

Interestingly, our study found no signiﬁcant correlations between testosterone levels

and cognitive performance in men or women. This ﬁnding may be explained by inter-

preting the results obtained in the context of the age and hormonal characteristics of our

sample. The absence of testosterone effects in our study contrasts with some previous

research showing testosterone’s inﬂuence on cognitive function, particularly in spatial

abilities and working memory [

]. However, studies showing testosterone’s cognitive

effects often focus on ageing populations [

–

]. As shown by Thilers et al. [

] in their

population-based study of 35–90-year-olds, associations between endogenous testosterone

levels and cognitive performance become more pronounced with age, particularly in tasks

involving processing speed and spatial abilities. This moderation according to age is partic-

ularly important because testosterone levels begin to gradually decline, by about 1–2% per

year, from the age of 30 [

], with the greatest decline observed in the sixth decade of

life [

]. Our results from a young adult sample suggest that these associations may not

be evident during the peak reproductive years when hormone levels are relatively stable.

This is consistent with other studies investigating the relationship between testosterone

levels in young adults and cognitive performance [

], including spatial abilities [

], navi-

gation and verbal ﬂuency tasks [

], and working memory [

]. The relationship between

testosterone and cognition is complex and potentially non-linear, as demonstrated by sev-

eral foundational studies [

], showing that both low and high testosterone levels are

associated with poorer cognitive ability. In our study, the male participants showed testos-

terone levels within the normal age-appropriate range (laboratory norm:

8.64–29.0 nmol/l

;

results of participants: M = 18.95

6.07 nmol/mL); the women’s testosterone variations

were minimal (ﬂuctuating within 0.45 nmol/mL between cycle phases). In people with

normal testosterone levels, as in our study, the effect of this hormone on cognitive function

can be challenging to observe. These ﬁndings collectively suggest that the absence of a

testosterone–cognition correlation in our study may be attributed to our sample’s age range

and the expected physiological hormone levels observed.

A limitation of our study is that our longitudinal assessment was restricted to two time

points (menstrual and pre-ovulatory phases), which limited our ability to comprehensively

assess hormonal inﬂuences throughout the menstrual cycle. To better understand the

complex relationships between oestrogen and progesterone throughout the cycle, future

studies should consider the three phases of the menstrual cycle. The second limitation

of our study was the lack of mood assessment, which prevented us from examining

how emotional state variations across the menstrual cycle might have inﬂuenced the

observed cognitive differences. Recent research suggests that menstrual cycle-related

cognitive changes are more pronounced in women with premenstrual dysphoric disorder

(PMDD), speciﬁcally regarding executive function impairments [

]. Nevertheless, in

Biology 2025,14, 1060 19 of 22

our study, women with dysphoric disorder were excluded from enrolment. Future research

should incorporate mood measures, as emotional states may act as moderating variables

inﬂuencing the magnitude of cognitive performance differences observed between cycle

phases and between sexes. A third limitation was the relatively small sample size, which

may have constrained the statistical power of our ﬁndings. This was primarily due to the

logistical challenges of conducting the study. Future studies with larger and more diverse

samples would enhance the robustness and generalizability of the results.

5. Conclusions

Our ﬁndings demonstrate three key aspects of hormone–cognition interactions: (1) en-

hanced cognitive performance during the pre-ovulatory phase compared to the menstrual

phase in women, only in verbal working memory and attention; (2) phase-dependent

sex differences between men and women in processing speed are present only during

women’s menstrual phase and absent during the pre-ovulatory phase; and (3) distinct

hormone–cognition relationships in men and women vary according to the menstrual cycle

phase. These results highlight the necessity of considering the phases of the menstrual

cycle in scientiﬁc and clinical research where cognitive functions are assessed, especially in

studies on sex differences.

Supplementary Materials: The following supporting information can be downloaded at: https:

//www.mdpi.com/article/10.3390/biology14081060/s1. The Supplementary Materials contain raw

data on hormone levels and cognitive test results.

Author Contributions: Conceptualisation, A.K.S. and P.J.W.; Data curation, A.K.S., K.M.M. and

B.N.; Formal analysis, A.K.S. and A.B.-G.; Funding acquisition, A.K.S.; Investigation, A.K.S., K.M.M.

and B.N.; Methodology, A.K.S. and A.B.M.; Project administration, A.K.S.; Supervision, P.J.W. and

A.B.M.; Visualisation, A.K.S., K.M.M., B.N. and A.B.-G.; Writing—original draft, A.K.S. and K.M.M.;

Writing—review and editing, M.M., P.J.W. and A.B.M. All authors have read and agreed to the

published version of the manuscript.

Funding: The research was funded by the Medical University of Gdansk—“Excellence Initiative—

Research University” Program. Additional support was provided to M.M. through the ICREA

under the ICREA Academia program. A.B.-G. received a pre-doctoral fellowship [grant number

FPU18/04344].

Institutional Review Board Statement: The study was conducted in accordance with the Declaration

of Helsinki. The study protocol was approved by the Independent Bioethics Commission for Research

at the Medical University of Gdansk (NKBBN/398/2021 and NKBBN/398-14/2023).

Informed Consent Statement: Informed consent was obtained from all individual participants

included in the study.

Data Availability Statement: The data supporting the conclusions of this article are included within

the article and its Supplementary Materials.

Acknowledgments: The authors thank all the participants involved in this study.

Conﬂicts of Interest: The authors declare no conﬂicts of interest.

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Menstrual Cycle Phase Influences Cognitive Performance in Women and Modulates Sex Differences: A Combined Longitudinal and Cross-Sectional Study PDF Free Download

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