1. Context
2. Objectives
3. Methods
4. Results
4.1. Study Selection
4.2. Summary of Included Studies
4.3. Synthesis of Findings
| Ref. | Authors (y) | Approx. Sample Size | EEG Approach | Brand/Marketing Context | Key Findings |
|---|---|---|---|---|---|
| 1 | Brown et al. (2012) (29) | 12 | EEG+self-report | Manufacturer vs. private-label brands | Price strongly influenced brand switching, with half of participants switching to private-label when aware of cost differences. |
| 2 | Boshoff (2016) (35) | 24 | EEG+EMG | Brand tarnishment (legal/managerial context) | Mild brand tarnishment did not produce significant negative emotional or economic harm for established brands. |
| 3 | Handy et al. (2010) (34) | 16 | ERPs (P1, N2, LPP) | Rapid hedonic evaluations of logos | Disliked logos elicited stronger negative neural responses within ~150 - 200 ms, showing immediate, implicit aesthetic judgments. |
| 4 | Ma et al. (2007) (33) | 16 | ERPs (N270) | Brand extension (beverage brand to unrelated products) | Higher N270 amplitude reflected conflict when brand extensions were perceived as highly incongruent. |
| 5 | Jin et al. (2015) (32) | 18 | ERPs (N400) | Brand extension vs. new brand creation | N400 amplitude indicated stronger brand-product associations for well-matched extensions, faster decision-making for brand extensions. |
| 6 | Ma et al. (2008) (31) | ~16 | ERPs (P300) | Brand extension congruity | Larger P300 amplitudes for congruent extensions; Incongruent extensions triggered additional N400 conflict processing. |
| 7 | Wang et al. (2012) (30) | ~20 | ERPs (N400) | Unconscious brand extension categorization | N400 reflected automatic categorization; Incongruent extensions produced higher conflict activity even without explicit judgments. |
| 8 | Yang et al. (2018) (38) | ~30 | ERPs (N2, P300, N400) | Service-to-service brand extensions | Two-stage process: Early detection of improbable extensions (P300), then semantic integration (N400) for mid-/high-fit conditions |
| 9 | Gholami Doborjeh et al. (2018) (36) | 20 | SNN+ERP | Brand familiarity (logos) | SNN accurately classified familiar vs. unfamiliar logo responses; higher spiking intensity and broader connectivity for familiar logos |
| 10 | Yang and Kim (2019) (37) | 19 | ERPs (N2, P300) | Service-to-service brand extension (population-level) | Higher P300 amplitudes for high-fit stimuli, reflecting more robust and consistent semantic memory retrieval across participants |
| 11 | Fudali-Czyz et al. (2016) (39) | 20 | ERPs (N270, P300, N400) | Brand extension among indo-european speakers | Explicit categorization (N270/P300) drove acceptance or rejection; Incongruence triggered more negative N400. |
| 12 | Xu et al. (2023) (16) | 36 | EEG+GSR+self-report | Brand personality (competence, sincerity, etc.) | Discrepancies emerged between self-reported attraction and physiological measures, highlighting subconscious vs. conscious responses. |
| 13 | Bosshard and Walla (2023) (20) | 20 | EEG+IAT+self-report | EC and brand attitudes | EEG detected attitude shifts post-conditioning even when self-reports/IAT showed minimal changes; Negative EC had stronger effects. |
| 14 | Guo et al. (2018) (18) | ~40 | EEG+eye-tracking+self-report | Product placement disclosures | Disclosures boosted brand recognition (higher fixation times, frontal gamma) but reduced brand attitudes due to increased skepticism. |
| 15 | Zhang et al. (2019) (19) | ~20 (all female) | ERPs (N200, N400, LPP) | Luxury brands (authentic vs. counterfeit) | Counterfeit goods elicited larger N200/N400 for incongruent logos; Prominent counterfeit logos triggered higher LPP (self-presentation). |
| 16 | Wang et al. (2022) (17) | ~30 | EEG (theta-band oscillations)+behavioral | COO stereotypes and brand positioning | Theta-band activity indicated conflict for incongruent COO-positioning combos (competence vs. warmth); Congruence boosted purchase intent. |
| 17 | Wang et al. (2016) (24) | 30 | EEG spectral dynamics+behavioral | Narrative advertising and exposure frequency | Narratively structured+multiple exposures generated higher emotional engagement (theta/beta/gamma) and stronger product preferences. |
| 18 | Dini et al. (2022) (22) | 32 | ERPs (N400)+theta-band analysis | Brand logo congruity vs. incongruity | Incongruent logos triggered larger negative N400 and higher theta power, indicating semantic mismatch and greater cognitive load. |
| 19 | Lucchiari and Pravettoni (2012) (21) | 26 | EEG (theta, beta) | Brand attachment (mineral water labels) | Favorite brands showed reward-like beta increases; Unknown brands elicited higher frontal theta indicating conflict/uncertainty. |
| 20 | Camarrone and Van Hulle (2019) (23) | ~24 | ERPs (N400)+semantic priming | Brand association (Netflix vs. Rex&Rio) | N400 indicated distinct brand associations (TV vs. relaxation); Self-reports could not distinguish subtle differences in brand identity. |
| 21 | Ma et al. (2021) (15) | 22 | Recurrent neural network (t-SNE+LSTM) | Brand extension acceptance (EEG classification) | Model achieved ~85% accuracy in predicting acceptance/rejection; Outperformed standard classifiers by ~20%. |
| 22 | Garczarek-Bak and Disterheft (2018) (26) | 21 | EEG frontal asymmetry+logistic regression | Purchase decisions: National vs. private labels | Beta asymmetry predicted higher purchase intentions for national brands; GSR/EMG were not significant predictors. |
| 23 | Pozharliev et al. (2015) (27) | ~30 (females) | ERPs (P2, P3, LPP) | Emotional responses to luxury vs. basic brands (social context) | Luxury products elicited greater LPP in social presence; Social context amplified emotional responses compared to viewing alone. |
| 24 | Ozbeyaz (2021) (28) | 11 | EEG+ML (PCA+ANN) | Branded vs. unbranded smartphones | Achieved 72% accuracy in distinguishing branded vs. unbranded EEG responses; Frontal channels (AF3-F7) critical for classification. |
| 25 | Aliagas et al. (2024) (25) | ~28 (young gamers) | EEG+eye-tracking | In-game advertising (congruence, prominence, familiarity) | Incongruent brand placements captured more attention (longer fixations, higher theta), yielding better recall but increased cognitive load. |
Abbreviations: EEG, electroencephalography; EMG, electromyography; ERP, event-related potential; SNN, spiking neural network; GSR, galvanic skin response; IAT, implicit association test; EC, evaluative conditioning; COO, country-of-origin.
4.4. Quality Assessment
| Titles | Authors (y) | Risk of Bias | Applicability Concerns | |||||
|---|---|---|---|---|---|---|---|---|
| Patient Selection | Index Test | Reference Standard | Flow and Timing | Patient Selection | Index Test | Reference Standard | ||
| A novel recurrent neural network to classify EEG signals for customers' decision-making behavior prediction in brand extension scenario | Ma et al. (2021) (15) | Low | Low | Low | Low | High | Low | Low |
| The neurophysiological mechanisms underlying brand personality consumer attraction: EEG and GSR evidence | Xu et al. (2023) (16) | Low | Low | Low | Low | Moderate | Low | Low |
| Country-brand fit: The effect of COO stereotypes and brand positioning consistency on consumer behavior | Wang et al. (2022) (17) | Moderate | Low | Low | Low | Moderate | Low | Low |
| Applying eye tracking and EEG to evaluate the effects of placement disclosures on brand responses | Guo et al. (2018) (18) | Moderate | Low | Low | Low | Moderate | Low | Low |
| Consumers implicit motivation of purchasing luxury brands: An EEG study | Zhang et al. (2019) (19) | Moderate | Low | Low | Low | Moderate | Low | Low |
| Sonic influence on initially neutral brands: Using EEG to unveil the secrets of audio evaluative conditioning | Bosshard and Walla (2023) (20) | Moderate | Low | Low | Low | Moderate | Low | Low |
| The effect of brand on EEG modulation: A study on mineral water | Lucchiari and Pravettoni (2012) (21) | Low | Low | Low | Low | Moderate | Low | Low |
| EEG theta and N400 responses to congruent versus incongruent brand logos | Dini et al. (2022) (22) | Low | Low | Low | Low | Moderate | Low | Low |
| Measuring brand association strength with EEG: A single-trial N400 ERP study | Camarrone and Van Hulle (2019) (23) | Low | Low | Low | Low | Moderate | Low | Low |
| EEG spectral dynamics of video commercials: Impact of the narrative on the branding product preference | Wang et al. (2016) (24) | Low | Low | Low | Low | Moderate | Low | Low |
| Unravelling cognitive processing of in-game brands using eye tracking and EEG: Incongruence fosters it | Aliagas et al. (2024) (25) | Moderate | Low | Low | Low | Moderate | Low | Low |
| EEG frontal asymmetry predicts FMCG product purchase differently for national brands and private labels | Garczarek-Bak and Disterheft (2018) (26) | Low | Low | Low | Low | Moderate | Low | Low |
| Merely being with you increases my attention to luxury products: Using EEG to understand consumers emotional experience | Pozharliev et al. (2015) (27) | Moderate | Low | Low | Low | Moderate | Low | Low |
| EEG-based classification of branded and unbranded stimuli associating with smartphone products | Ozbeyaz (2021) (28) | Low | Low | Low | Low | Moderate | Low | Low |
| The story of taste: Using EEGs and self-reports to understand consumer choice | Brown et al. (2012) (29) | Unclear | Low | Low | Low | Low | Low | Low |
| N400 as an index of uncontrolled categorization processing in brand extension | Wang et al. (2012) (30) | Unclear | Low | Low | Low | Low | Low | Low |
| P300 and categorization in brand extension | Ma et al. (2008) (31) | Unclear | Low | Low | Low | Low | Low | Low |
| Extending or creating a new brand: Evidence from a study on ERPs | Jin et al. (2015) (32) | Unclear | Low | Low | Low | Low | Low | Low |
| ERP N270 correlates of brand extension | Ma et al. (2007) (33) | Unclear | Low | Low | Low | Low | Low | Low |
| ERP evidence for rapid hedonic evaluation of logos | Handy et al. (2010) (34) | Unclear | Low | Low | Low | Low | Low | Low |
| The lady doth protest too much: A neurophysiological perspective on brand tarnishment | Boshoff (2016) (35) | Unclear | Low | Low | Low | Low | Low | Low |
| Modelling peri-perceptual brain processes in a deep learning SNN architecture | Gholami Doborjeh et al.(2018) (36) | Unclear | Low | Low | Low | Low | Low | Low |
| Group-level neural responses to service-to-service brand extension | Yang and Kim (2019) (37) | Unclear | Low | Low | Low | Low | Low | Low |
| Characteristics of human brain activity during the evaluation of service-to-service brand extension | Yang et al. (2018) (38) | Unclear | Low | Low | Low | Low | Low | Low |
| Controlled categorisation processing in brand extension evaluation by Indo-European language speakers: An ERP study | Fudali-Czyz et al. (2016) (39) | Unclear | Low | Low | Low | Low | Low | Low |
Abbreviations: EEG, electroencephalography; GSR, galvanic skin response; ERP, event-related potential; COO, country-of-origin; FMCG, fast-moving consumer good.
