Processing characteristics of visuospatial working memory in map cognition by orienteering athletes: evidence from behavioral and EEG studies

Introduction

Maps, the carriers of geospatial information, serve as a graphical representation of an individual’s spatial cognitive abilities (Dong et al., 2019). Geospatial information is presented visually through graphics, symbols, colors, etc., substantially augmenting human capacity for rapid environmental comprehension and spatial awareness. Map cognition refers to process by which an individual, while exploring unfamiliar environments, engages higher brain functions to form a comprehensive mental model including spatial layouts such as roads, directions, and distances, as well as temporal relationships and non-spatial information (Tolman, 1948). As a system for the storing and processing of visual and spatial information (Zarantonello et al., 2024), visuospatial working memory (VSWM) provides individuals with the capacity to temporarily store and process map-related information. The improvement in VSWM ability can substantially enhance an individual’s performance in map cognition tasks, allowing them to understand and remember the layout of their environment more accurately (Harris & Wolbers, 2014; Hegarty et al., 2006). This indicates that the construction of a “cognitive map” helps individuals better understand the spatial relationships between objects, and the formation and consolidation of visuospatial memory provide the foundation for spatial imagination.

In competitive sports, it is not only necessary for athletes to store and refine information from surrounding environment, but it is even more necessary to actively retrieve relevant internal representations, so that the newly acquired information can be deeply integrated to adapt to the demands of the current situation or task (Repovs & Baddeley, 2006). Research indicates that compared with novices, expert athletes demonstrate a significant advantage in memory store and retrieval. For example, in sports such as cricket and football, expert athletes demonstrate higher accuracy and efficiency when recalling the player layout on the court (Houlston & Lowes, 1993; Panchuk & Vickers, 2006). In orienteering competitions, maps are indispensable tools for athletes, especially for spatial cognition and navigation. According to the theory of map spatial cognition (Huang et al., 2024), athletes first need to visually search for key information such as checkpoints, routes, buildings, etc. from complex map information, and then mobilize the visuospatial working memory system to memorize the relevant information and match and adjust it with the field environment in real time to quickly reach each checkpoint and complete the task (Liu & He, 2016). In this process, orienteers need to have strong VSWM to carry out tasks like visual search, memory recall, and decision-making. This study has shown that specialized VSWM training can significantly enhance orienteers’ map-reading performance (Wang, 2022). The capacity of VSWM influences cognitive decision-making in orienteers differently when engaging in precise versus rough map-reading tasks (Liu, 2021). Elite orienteers typically exhibit exceptional visual memory abilities, further supporting the importance of VSWM in orienteering (Wang, 2010). Although behavioral studies have widely confirmed the memory advantages of expert athletes, the underlying neural mechanisms—particularly the specific patterns of brain activity involved in memory storage and retrieval, as well as the differences in these processes—still require further investigation.

The Baddeley–Hitch model (abbreviated as the “B&H model”) posits that when processing short-term information, the brain not only retains information, but also manipulates and prepossess it during this retention process (Baddeley & Hitch, 1977). Specifically, the memory process is delineated into two critical phases: the first is the storage process, where information is effectively encoded and initially stored in the short-term memory system; the second is the retrieval phase, involving the ability to quickly and accurately retrieve the required information from stored data. Some studies have found that there are differences in the brain areas activated by individuals during the memory storage phase and the memory extraction phase (Kuhl & Chun, 2014). Theta oscillations can coordinate neuronal activity related to human cognition, particularly memory functions (Herweg, Solomon & Kahana, 2020; Rozengurt et al., 2023), and can be enhanced in the frontal and temporal lobes during visuospatial and visual information encoding (Xie et al., 2021; Jaiswal, Ray & Slobounov, 2009). On the other hand, Alpha oscillations facilitate memory encoding by suppressing distractibility (Strunk & Duarte, 2019), and a reduction in αband activity in the frontal region indicates higher cognitive neural efficiency (Cona et al., 2019). Therefore, the study utilizes electroencephalogram (EEG) technology to monitor θ and α neural oscillations in orienteers of varying skill levels across different memory phases with the goal of revealing the cognitive features of VSWM processing in orienteers.

In summary, this study employs a recall paradigm, uses orienteering competition maps as experimental materials, designs a map cognition task, and utilizes EEG technology to explore the influence of orienteering training experience on the processing of visual short-term working memory (VSWM) of orienteers. The study hypothesizes that, during map cognition, the expert group will exhibit a motor expertise advantage, and significant differences in brain activity between the experts and novices will be observed in the frontal and temporal lobes during the memory storage and retrieval phases.

Materials and Methods

Measuring instruments

Experiments were performed using the eye-tracker aSee pro (7 Invensun, Beijing, China) to present the stimuli. The eye-tracker was in a local area network (LAN) with the EEG acquisition device, and the eye-tracking device sent signals to the EEG device via a wireless synchronization box at the beginning of each stimulation to ensure the accuracy of the data.

EEG data were acquired using a wireless multichannel EEG acquisition system (ZhenTec NT1, ZhenTec Intelligence Technologies Co., Ltd., Xi’an, China) , equipped with 32 active electrodes. The system specifications included an input impedance of 1 GΩ, input noise <0.4 µV, common-mode rejection ratio (CMRR) of −120 dB, electrode-scalp impedance maintained below 10 kΩ, and a sampling rate of 500 Hz.

As shown in Fig. 1, 32 EEG electrodes were positioned according to the 10-10 system on a custom elastic fabric cap, with the following regional distribution:

Positioning electrode: GND, Cz

Non-functional electrodes: HEOL, HEOR

Frontal region: FP1, FP2, F3, F4, FC3, FC4, F7, F8, FT7, FT8

Central region: Fz, FCz, Cz, CPz, Pz

Parietal region: C3, C4, CP3, CP4, P3, P4

Temporal region: T3, T4, TP7, TP8, T5, T6

Occipital region: Oz, O1, O2

Experimental design and materials

A 2 (Group: Expert, Novice) × 2 (Memory Process: storage, retrieval) mixed-design experiment was conducted, with the behavioral dependent variable being the participants’ task completion rate and the neural dependent variable being the participants’ neural oscillations in the θ and α frequency bands.

Stimuli consisted of orienteering competition maps (Fig. 2), developed by five certified cartographers (National Senior Cartographer Level). A total of twenty prototype maps were initially created, and the difficulty of the maps was assessed by 100 online volunteers who used a 10-point Likert scale (mean score: 4.55 ± 0.61, indicating moderate difficulty). Ten maps were selected for formal testing, supplemented by two practice maps.

Procedure

Prior to the experiment, participants were asked to complete a self-designed questionnaire documenting their gender, age, years of training, sport grade. During testing, participants were seated 60 cm away from the monitor. They were required to refrain from moving any part of their body throughout the data recording process.

The experiment comprised a practice phase and a formal experimental phase. Participants first completed practice trials (2 test maps) to familiarize themselves with experimental procedure so that they could better control the amplitude of movements and reduce muscle activity in the formal experiment. All materials presented during practice phase were not used in the formal phase, and no data were collected during the practice phase.

Prior to the formal experiment, three minutes of resting-state EEG data were collected. The formal phase consisted of 10 trials, each comprising two sequential tasks: memory storage and memory retrieval, with maps presented sequentially. As illustrated in Fig. 3, each trial commenced with a central fixation cross (“+” symbol) displayed in the center of the screen. Once the participant’s gaze was fixed on the central point, the experimenter initiated the presentation of the experimental map by pressing a button.Participants were regularly prompted to relax their bodies during the experiment, and the EEG data were monitored in synchronized real-time, and timely guidance was given to adjust the posture or speed of movement when electromyography (EMG) artifacts were detected in order to safeguard the signal quality.

During the memory storage task, participants observed and memorized map information for 20 s. Following a 20-second intermission, the memory retrieval task required participants to reproduce the previously viewed map on paper, including map features and routes, within 20 s. The trial ended when participants pressed a key upon completion. If no button response was recorded within 20 s, the corresponding data were excluded from subsequent statistical analyses. Each trial concluded with a 20-second inter-trial interval before automatic progression to the next trial, totaling 10 complete trials.

Results

Behavioral results

An independent samples t-test was used to analyze the behavioral outcomes of orienteers with different skill levels in the map cognition task. As shown in Fig. 4, the expert group demonstrated significantly higher map recall scores than the novice group (t(42) = 7.006, P = 0.000 < 0.001, Cohen’s d = 1.66), and the expert group also exhibited significantly shorter map recall times compared to the novice group (t(42) = −7.629, P = 0.000 < 0.001, Cohen’s d = 2.30). Descriptive statistics are summarized in Table 2.

Table 2:

Descriptive statistical results of behavioral performance in map cognition task for orienteers with different skill levels (M ± SD).

	Expert group	Novice group
Map recall scores	8.57 ± 0.41	7.66 ± 0.46
Map recall times	10.34 ± 1.30	14.42 ± 2.14

DOI: 10.7717/peerj.19817/table-2

Results of neural oscillations

A repeated-measures ANOVA was conducted to analyze the θ-band neural oscillations during the memory storage and retrieval phases among orienteers of different skill levels. The results, as shown in Fig. 5, revealed a significant main effect of group in the frontal region (F(1, 42) = 4.694, P = 0.036, η² = 0.101), with the expert group exhibiting significantly lower θ-band neural oscillations in the frontal region during both the memory storage and retrieval phases compared to the novice group. Descriptive statistics are presented in Table 3.

Table 3:

Descriptive statistical results of θ-band neural oscillations in map cognition task for orienteers with different skill levels (M ± SD).

	Expert group		Novice group
	Memory storage (Hz)	Memory retrieval (Hz)	Memory storage (Hz)	Memory retrieval (Hz)
Frontal region	0.71 ± 0.12	0.74 ± 0.14	0.79 ± 0.28	0.82 ± 0.21
Central region	0.66 ± 0.13	0.66 ± 0.15	0.75 ± 0.30	0.68 ± 0.17
Parietal region	0.63 ± 0.13	0.67 ± 0.15	0.67 ± 0.26	0.64 ± 0.10
Temporal region	0.96 ± 0.21	0.99 ± 0.19	0.97 ± 0.36	0.95 ± 0.20
Occipital region	0.97 ± 0.35	0.91 ± 0.27	1.01 ± 0.49	0.98 ± 0.36

DOI: 10.7717/peerj.19817/table-3

A repeated-measures ANOVA was conducted to analyze the α-band neural oscillations during the memory storage and retrieval phases among orienteers of different skill levels. The results, illustrated in Fig. 6, showed significant main effects of group in the frontal (F(1, 42) = 5.004, P = 0.031 < 0.05, η² = 0.106) and temporal regions (F(1, 42) = 33.243, P = 0.000 < 0.001, η² = 0.442). The expert group demonstrated significantly higher α-band neural oscillations in these regions during both the memory storage and retrieval phases compared to the novice group. In the parietal region (F(1, 42) = 9.938, P = 0.003 < 0.01, η² = 0.191), a significant main effect of memory phase was observed, with both expert and novice groups exhibiting higher α-band neural oscillations in the parietal region during the memory storage phase than during the retrieval phase. Descriptive statistics are summarized in Table 4.

Discussion

The ability to rapidly store and retrieve information enables orienteers to respond promptly to dynamic competition environments, swiftly adjust tactical strategies, and gain a competitive edge through agile decision-making. The results of this study demonstrate that expert group performs significantly better than the novice group in map cognition tasks, exhibiting higher levels of rationality and shorter response times. Consistent with findings from Smith et al. (2021), the expert group demonstrates superior memory abilities when processing novel, domain-general stimuli and monitoring spatial changes. In rapid changing sports scenarios, athletes must integrate their motor skills with cognitive and perceptual processes to make rapid and accurate decisions. Expert athletes accomplish visuospatial working memory tasks by combining perceptual information with chunks stored in long-term memory, and this strategic encoding ability is crucial to their enhanced memory performance compared to novice group (Whitaker et al., 2020). Furthermore, in line with the theory of the deliberate practice theory, extensive and focused training allows expert athletes to develop significant cognitive advantages over novices (Macnamara & Maitra, 2019). In orienteering competitions, athletes must rapidly integrate environmental information and make decisions based on prior knowledge and experience. Expert orienteers combine VSWM with spatial cognition and information integration skills to form an efficient and flexible competitive system. Consequently, they demonstrate a marked superiority over novice orienteers in map cognition tasks.

The EEG results revealed that the expert group exhibited significantly lower θ-band neural oscillations in the frontal region compared to the novice group. As demonstrated by Badre & Wagner (2007), the frontal cortex plays a key role in supporting cognitive control and executive functions, helps individuals reactivate and retrieve relevant memory information. According to the neural efficiency hypothesis, experts typically display higher neural efficiency than novices when performing the same tasks, as reflected by reduced activation in task-related brain regions (Ge et al., 2021). θ-wave activity in the cerebral cortex, particularly reduced fluctuations in the frontal region, is linked to optimal athletic performance (Filho, Dobersek & Husselman, 2021). Through prolonged training, expert athletes develop exceptional spatial cognition abilities, enabling them to establish a more efficient spatial information processing mechanism, consistent with these findings. In the process of memory storage, they rapidly identify critical map features including: terrain characteristics and landmark symbols, and effectively match this information to the real-world environment. During memory retrieval, they rapidly retrieve task-relevant details such as terrain features and landmark locations, from memory, which reduces the demand on the frontal lobe.

Additionally, the expert group displayed significantly higher α-band neural oscillations in the central and temporal regions compared to the novice group. In both the expert and novice groups, α-band neural oscillations were higher in the parietal region during the memory storage phase compared to the retrieval phase. This α-band neural activity is associated with specific attentional and spatial perceptual processes (Andrew, Steven & Paul, 2024). Increased α-band oscillations are related to the suppression of irrelevant information (Bastos et al., 2018; Borghini et al., 2018) and tend to increase with higher cognitive load (Paul et al., 2010; Tuladhar et al., 2007). During memory storage, the continuous transfer of information necessitates frequent memory refreshing, leading to heightened activation in brain regions responsible for memory updating and encoding (Liang et al., 2018). During memory retrieval, the memory information stored in the brain prior to neural changes will be activated. The individual needs to focus attention on the retrieved information and collaborate with other brain regions to successfully retrieve relevant memories (Chen et al., 2022). Long-term physical activity can reshape how the brain encodes memories (Jin, Ding & Zhou, 2022; Zhou & Jin, 2021). Compared to novice athletes, expert ones demonstrate significantly enhanced cognitive functions, such as information processing and motor planning, through long-term training. In map cognitive tasks, expert athletes are better at filtering relevant stimuli from irrelevant information, responding to them, and retaining them in memory. This is associated with increased α-band neural oscillations in the central region. The temporal lobe, a key hub for memory processing, plays a vital role in classifying and representing spatial scenes and spatial-related dimensional information, ensuring perceptual accuracy and mitigating interference from similar information (Zeng et al., 2024). Merim, Peter & Fernand (2008) employed functional magnetic resonance imaging (fMRI) to investigate expert-novice differences between experts and novices in chess, and found that chess experts exhibited more pronounced activation in the temporal lobe. Consistent with the findings of this study, expert athletes undergo brain adaptations driven by specialized knowledge and skills, leading to the collaborative engagement of the temporal lobe, which influences memory task performance and ultimately improves decision-making. The parietal cortex plays a role in the processing of perceptual information and the construction of spatial cognition, and can help individuals match current perceptual information with information in long-term memory, thereby triggering memory extraction (Rizza et al., 2024). Alpha-band neural oscillations in the parietal lobe were significantly higher in the memory storage phase than in the memory extraction phase for both the expert and novice groups. The cognitive processing of specialized scenario maps is closely tied to athletes’ unique professional knowledge structure. During memory storage tasks, athletes rapidly retrieve and process critical map features such as shapes, symbols, colors, and legend annotations on maps, with both speed and accuracy. In contrast, during memory retrieval tasks, pre-existing memory information, shaped by long-term training, is activated. Athletes must mobilize cognitive resources to regulate distracting interference information (Fan & Zheng, 2019), which results in an increased cognitive load and elevated α-band neural oscillations in the parietal cortex.

Distinct neural optimizations and adaptations are reflected in the differences in brain activity among orienteers of varying skill levels during map cognition.These differences not only highlight variations in their map cognition abilities but also offer valuable insights for future training and interventions.Through targeted training approaches, the map cognition performance of novice orienteers can be improved.

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