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To investigate whether doing a job that demands navigational experience and spending more years in that job affects the volume of the hippocampus.

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Voxel based morphology and pixel counting were used to analyse grey matter and the volume of the hippocampus to compare a group of 16 male, right-handed taxi drivers from London to 15 non-taxi drivers also male right handed and from London. Correlational analysis also explored the relationship between time spent as a taxi driver and hippocampal volume.

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Abstract

Structural MRIs of the brains of humans with extensive navigation experience, licensed London taxi drivers, were analyzed and compared with those of control subjects who did not drive taxis. The posterior hippocampi of taxi drivers were significantly larger relative to those of control subjects. A more anterior hippocampal region was larger in control subjects than in taxi drivers. Hippocampal volume correlated with the amount of time spent as a taxi driver (positively in the posterior and negatively in the anterior hippocampus). These data are in accordance with the idea that the posterior hippocampus stores a spatial representation of the environment and can expand regionally to accommodate elaboration of this representation in people with a high dependence on navigational skills. It seems that there is a capacity for local plastic change in the structure of the healthy adult human brain in response to environmental demands.

One important role of the hippocampus is to facilitate spatial memory in the form of navigation ( 1). Increased hippocampal volume relative to brain and body size has been reported in small mammals and birds who engage in behavior requiring spatial memory, such as food storing ( 2). In some species, hippocampal volumes enlarge specifically during seasons when demand for spatial ability is greatest ( 2, 3). In the healthy human, structural brain differences between distinct groups of subjects (for example, males and females, ref. 4, or musicians and nonmusicians, ref. 5) have been documented. From existing studies, it is impossible to know whether differences in brain anatomy are predetermined or whether the brain is susceptible to plastic change in response to environmental stimulation. Furthermore, although lesion work ( 6, 7) and functional neuroimaging work ( 8) confirm the involvement of the human hippocampus in spatial memory and navigation, there is still debate about its precise role. Given the propensity of lower mammalian/avian hippocampi to undergo structural change in response to behavior requiring spatial memory ( 2, 3), the present study addressed whether morphological changes could be detected in the healthy human brain associated with extensive experience of spatial navigation. Our prediction was that the hippocampus would be the most likely brain region to show changes.

Taxi drivers in London must undergo extensive training, learning how to navigate between thousands of places in the city. This training is colloquially known as "being on The Knowledge" and takes about 2 years to acquire on average. To be licensed to operate, it is necessary to pass a very stringent set of police examinations. London taxi drivers are therefore ideally suited for the study of spatial navigation. The use of a group of taxi drivers with a wide range of navigating experience permitted an examination of the direct effect of spatial experience on brain structure. In the first instance, we used voxel-based morphometry (VBM) to examine whether morphological changes associated with navigation experience were detectable anywhere in the healthy human brain. VBM is an objective and automatic procedure that identifies regional differences in relative gray matter density in structural MRI brain scans. It allows every point in the brain to be considered in an unbiased way, with no a priori regions of interest. The data were also analyzed by using a second and completely independent pixel-counting technique within the hippocampus proper. Comparisons were made between the brain scans of taxi drivers, who had all acquired a significant amount of large-scale spatial information (as evidenced by passing the licensing examinations), and those of a comparable group of control subjects who lacked such extensive navigation exposure.

Methods

Subjects.

Right-handed male licensed London taxi drivers ( n = 16; mean age 44 years; range 32-62 years) participated. All had been licensed London taxi drivers for more than 1.5 years (mean time as taxi driver = 14.3 years; range = 1.5-42 years). The average time spent training to be a taxi driver before passing the licensing tests fully (i.e., time on The Knowledge) was 2 years (range 10 months to 3.5 years; some trained continuously, some part time). All of the taxi drivers had healthy general medical, neurological, and psychiatric profiles. The scans of control subjects were selected from the structural MRI scan database at the same unit where the taxi drivers were scanned. Those subjects below 32 and above 62 years of age were excluded as were females, left-handed males, and those with any health problems. After the application of these exclusion criteria, the scans of 50 healthy right-handed males who did not drive taxis were included in the analyses for comparison with the taxi drivers. Both the mean age and the age range did not differ between the taxi driver and control groups. We were also careful to ensure an even spread of subjects in each decade (for example, 41-50 years or 51-60 years) up to the upper limit of the oldest taxi driver, such that subjects were not clustered at one end of the age scale.

Image Acquisition.

Structural MRI scans were obtained with a 2.0 Tesla Vision system (Siemens GmbH, Erlangen, Germany) by using a T1-weighted three-dimensional gradient echo sequence (TR 9.7 ms; TE 4 ms; flip angle 12°; field of view 256 mm; 108 partitions; partition thickness 1.5 mm; voxel size 1 × 1 × 1.5 mm).

Image Analysis Method 1: VBM.

Data were analyzed by using VBM implemented with Statistical Parametric Mapping (SPM99, Wellcome Department of Cognitive Neurology) executed in matlab (Mathworks, Sherborn, MA). Detailed descriptions of the technique are given elsewhere ( 9, 10). Briefly, the subjects' data were spatially normalized into stereotactic space ( 11) by registering each of the images to the same template image by minimizing the residual sums of squared differences between them. The template was generated from the structural scans of 50 healthy males acquired in the same scanner used to collect the data for the current analysis (the scans of 13 of the control subjects used in the VBM analysis were included in the creation of this template). The spatially normalized images were written in voxels of 1.5 × 1.5 × 1.5 mm and segmented into gray matter, white matter, and cerebrospinal fluid by using a modified mixture cluster analysis technique. To reduce confounds caused by individual differences in gyral anatomy, the gray matter images were smoothed by using an isotropic Gaussian kernel of 4-mm full width at half maximum. The statistical model included a measure of total amount of gray matter in each brain as a confound (essentially the original values before normalization). Statistical tests involved locating regionally specific differences in gray matter between subject groups and were based on t tests and the general linear model. Significance levels were set at P < 0.05 (small volume correction for multiple comparisons, with 62 resolution elements comprising the volume of interest). To be consistent across the two analysis techniques, we defined the hippocampal regions the same way in both cases as described below.

Image Analysis Method 2: Pixel Counting.

The three-dimensional images from the 16 taxi drivers and a precisely age-matched sample of 16 normal controls taken from the 50 used in the VBM analysis were submitted for region-of-interest-based volumetric measurement of both hippocampi by using a well established pixel-counting technique ( 12, 13). The images were analyzed by one person experienced in the technique and blinded to subjects' identity as taxi drivers or controls and the VBM findings. Briefly, the images were reformatted into 1.5-mm-thick contiguous sections in a tilted coronal plane that was perpendicular to the long axis of the hippocampus. Hippocampal cross-sectional areas were measured for each slice along the whole length of the hippocampus. There were at least 26 contiguous slices (each 1.5-mm-thick) for each hippocampus of each subject, giving a total length of approximately 4 cm. Total hippocampal volume was calculated by summing the cross-sectional areas and multiplying by the distance between adjacent slices (i.e., 1.5 mm). These volumes were then corrected for intracranial volume (ICV), which was measured from the sagittal slices of the original three-dimensional data sets. Measurements for the most posterior slices violated assumptions of homogeneity of variance and were therefore not considered in the analyses, leaving the measurements for 24 slices. These were grouped into three regions ( 14): posterior hippocampus (6 slices), body (12 slices), and anterior (6 slices). Values for the component slices for a particular region were averaged, and the data were analyzed by ANOVA and correlations (significance level set at P < 0.05). We report the analyses on data uncorrected for ICV (when data were corrected for ICV, the results did not differ).

Results

VBM.

Significantly increased gray matter volume was found in the brains of taxi drivers compared with those of controls in only two brain regions, namely the right and the left hippocampi (Fig. 1 a and b). No differences were observed elsewhere in the brain. The increase in hippocampal gray matter volume was focal and limited to the posterior hippocampus bilaterally. The voxel of peak difference in gray matter density in the right hippocampus was at ( x, y, z) 31, −22, −13 (Z = 4.34) and, in the left hippocampus, was at −31, −28, −10 ( Z = 4.19). The area of difference extended in the y axis in the right hippocampus from −17 mm to −33 mm and in the left hippocampus from −18 mm to −34 mm. Controls showed a relatively greater gray matter volume bilaterally in anterior hippocampi relative to those of taxi drivers (Fig. 1 c). The voxel of peak difference in gray matter density in the right hippocampus was at 32, −7, −28 ( Z = 2.65) and in the left hippocampus was at −34, −7, −26 ( Z = 2.65). The anterior changes did not survive correction for multiple comparisons but were confirmed in the second analysis technique as described below.

Figure 1.

VBM findings. ( a Left) Sagittal section of an MRI scan with the hippocampus indicated by the red box. ( a Right) Coronal section through the MRI scan, again with the hippocampi indicated. ( b) The group results are shown superimposed onto the scan of an individual subject selected at random. The bar to the right indicates the Z score level. Increased gray matter volume in the posterior of the left and right hippocampi (LH and RH, respectively) of taxi drivers relative to those of controls, shown in the top of the figure in sagittal section. Underneath, the areas of gray matter difference are shown in coronal sections at three different coordinates in the y axis to illustrate the extent of the difference down the long axis of the hippocampus. ( c) Increased gray matter volume in the anterior of the left and right hippocampi of controls relative to those of taxi drivers, shown in sagittal section. Note that, although the Talairach and Tournoux ( 11) coordinate system was used to describe the locations of VBM differences in stereotactic space, the images were normalized with respect to a template based on a large number of brains scanned in the same scanner used to collect the current data (see Methods). Thus, the coordinates given refer to our brain template and only approximately to the Talairach and Tournoux template.

Pixel Counting.

Hippocampal volumes (both corrected and uncorrected for ICV) and ICV did not differ significantly between the two subject groups [right hippocampus: taxi drivers, uncorrected = 4,300 mm ³ (± 432), corrected = 4,159 mm ³ (± 420); controls, uncorrected = 4,255 mm ³ (± 424), corrected = 4,080 mm ³ (± 325); left hippocampus: taxi drivers, uncorrected = 4,155 mm ³ (± 410), corrected = 3,977 mm ³ (± 350); controls, uncorrected = 4,092 mm ³ (± 324), corrected = 3,918 mm ³ (± 224); ICV of taxi drivers = 1,521 mm ³ (± 145); controls = 1,540 mm ³ (± 107)].

Although the analysis revealed no difference in the overall volume of the hippocampi between taxi drivers and controls, it did reveal regionally specific differences in volume (Fig. 2). ANOVA (group by side) on anterior hippocampal volumes revealed a main effect of group, with control volumes significantly greater than those in taxi drivers [df ( 1, 30); F = 5; P < 0.05], a main effect of side, with the anterior right hippocampus being larger than the left [df ( 1, 30); F = 4.5; P < 0.05], and no interaction. Analysis of the volumes for the body of the hippocampus showed no interaction and no effect of group but a main effect of side, again right greater than left [df ( 1, 30); F = 5.4; P < 0.05]. Finally, analysis of volumes of the posterior hippocampus revealed a main effect of group, with taxi drivers having a greater posterior hippocampal volume than controls [df ( 1, 30); F = 4.1; P < 0.05]. Neither the interaction nor the main effect of side was significant.

Figure 2.

Volumetric analysis findings. The orientation of the slices measured in the volumetric analysis with respect to the hippocampus is shown ( Top Right Inset). A, anterior; B, body; P, posterior. ( Upper) The mean of the cross-sectional area measurements (uncorrected for ICV) for the three regions of the left hippocampus (LH). ( Lower) The means for the right hippocampus (RH). Taxi drivers had a significantly greater volume relative to controls in the posterior hippocampus, and controls showed greater hippocampal volume in the anterior. There was no difference between the two groups in the hippocampus body. *, P < 0.05.

Changes with Navigation Experience.

We examined the correlation between volume and amount of time spent as a taxi driver (including both training on The Knowledge and practicing as a qualified taxi driver). We found that length of time spent as a taxi driver correlated positively with volume in only one brain region, the right posterior hippocampus (Fig. 3 a). Correction for age was made by including it as a confounding covariate. The voxel of peak correlation in the right hippocampus was at 22, −33, 3 ( Z = 5.65). The extent of the area in the right hippocampus ranged in the y axis from −29 mm to −36 mm. The spatial extent of this area overlapped with the area showing greater volume in the categorical comparison of taxi drivers with controls. The VBM changes as a function of time (in months) spent as a taxi driver (corrected for age effects) and global gray matter are plotted in Fig. 3 b, where the data were considered within a linear model ( r = 0.6; P < 0.05). The correlation between time spent as a taxi driver (corrected for age) and the pixel-counting data indicated a similar relationship for the posterior hippocampus ( r = 0.5; P < 0.06). The pixel-counting data also showed a negative correlation between the time spent as a taxi driver and the volume of anterior hippocampal tissue ( r = −0.6; P < 0.05) as plotted in Fig. 3 c. When time as a taxi driver was corrected for age by expressing it as a percentage of age, the result was identical ( r = −0.6; P < 0.05). The data of one taxi driver were not included in the correlation analyses. He had been a taxi driver for 42 years, and the next nearest length of time was 28 years; thus, he was treated as an outlier and removed. The data of this subject were completely in line with the relationships as plotted; for example, his VBM response measure was 13.7.

Figure 3.

Correlation of volume change with time as a taxi driver. ( a Left) Sagittal section. ( a Right) Coronal section. The VBM group results are shown superimposed onto the scan of an individual subject selected at random. The bar to the right indicates the Z score level. The volume of gray matter in the right hippocampus was found to correlate significantly with the amount of time spent learning to be and practicing as a licensed London taxi driver, positively in the right posterior hippocampus ( b) and negatively in the anterior hippocampus ( c).

Discussion

The data presented in this report provide evidence of regionally specific structural differences between the hippocampi of licensed London taxi drivers compared with those of control subjects. Taxi drivers had a significantly greater volume in the posterior hippocampus, whereas control subjects showed greater volume in the anterior hippocampus. The converging results from these two independent analysis techniques indicate that the professional dependence on navigational skills in licensed London taxi drivers is associated with a relative redistribution of gray matter in the hippocampus. We further considered whether the volume differences between the groups could be incidental and unassociated with the navigational requirements of the taxi drivers. For example, could this particular arrangement of hippocampal gray matter predispose individuals to professional dependence on navigational skills? Although this explanation would be fascinating in itself, we tested this notion directly by examining the correlation between volume and amount of time spent as a taxi driver. Right hippocampal volume correlated with the amount of time spent as a taxi driver (positively in the posterior and negatively in the anterior hippocampus). We believe that these data suggest that the changes in hippocampal gray matter-at least on the right-are acquired. As such, this finding indicates the possibility of local plasticity in the structure of the healthy adult human brain as a function of increasing exposure to an environmental stimulus.

Previous rodent and monkey studies have found the dorsal (posterior) hippocampus to be preferentially involved in spatial navigation ( 15- 18). Such an involvement may also be true for the rostral part of the hippocampus in birds ( 19). There are also many more cells with spatial correlates-place cells ( 20)-in the dorsal than in the ventral rat hippocampus ( 21). Functional neuroimaging studies of navigation in humans show that the retrieval or use of previously learned navigational information is associated with activation of the posterior hippocampus ( 22- 24). Patients with lesions of the hippocampus that spare the posterior aspect have been reported to be unimpaired at recalling routes learned before lesion onset ( 6). Exactly how much posterior hippocampus needs to be spared to support the recall of "old" cognitive maps is not clear. For instance, it has been reported recently that a patient with extensive damage to the medial temporal region bilaterally, including the hippocampus, could recall the town where he grew up many years before ( 25). The authors of that report inferred from this fact that the medial temporal region is not the repository of spatial maps. However, they also allude to some sparing of the hippocampal tissue near the lateral ventricles bilaterally. It is therefore not clear whether this tissue was contributing to the recall of the patient's spatial map. Unfortunately, the patient was not tested by using functional neuroimaging during the recall of these old memories, which could have confirmed whether the remaining hippocampal tissue was still functional. We would predict that it was.

Our finding that the posterior hippocampus increases in volume when there is occupational dependence on spatial navigation is evidence for functional differentiation within the hippocampus. In humans, as in other animals, the posterior hippocampus seems to be preferentially involved when previously learned spatial information is used, whereas the anterior hippocampal region may be more involved (in combination with the posterior hippocampus) during the encoding of new environmental layouts.

A basic spatial representation of London is established in the taxi drivers by the time The Knowledge is complete. This representation of the city is much more extensive in taxi drivers than in the control subjects. Among the taxi drivers, there is, over time and with experience, a further fine-tuning of the spatial representation of London, permitting increasing understanding of how routes and places relate to each other. Our results suggest that the "mental map" of the city is stored in the posterior hippocampus and is accommodated by an increase in tissue volume. These results challenge the traditional view that the hippocampus has a transient role in memory ( 26) at least in relation to spatial navigation and the posterior hippocampus. The need to navigate is a basic cross-species behavior. The hippocampus is a phylogenetically old part of the brain, with an intrinsic circuitry that may have evolved to deal with navigation. Undoubtedly, in humans, the functions of the hippocampus have adapted to accommodate other types of memory, such as episodic memory ( 27- 29), but the hippocampus retains an ability to store large-scale spatial information ( 1).

Our findings from two independent measurement techniques are consistent with patient ( 6) and functional neuroimaging ( 22) reports of bilateral hippocampal involvement in successful navigation. Unlike right hippocampal volume, however, left hippocampal volume did not correlate with years of taxi-driving experience, suggesting that the left hippocampus participates in spatial navigation and memory in a different way from the right hippocampus. We may speculate that the left hippocampus complements its partner by storing memories of people and events that occur in the rich context of taxi driving in the real world, where an over-arching framework-such as integrating information into an existing map-is not required ( 30).

Although the hippocampus does not support navigation in isolation from other brain regions, it seems to be crucial to the storage and use of mental maps of our environments. The prolonged accumulation of other types of nonnavigational information may also produce similar hippocampal changes. Our present findings, however, corroborated as they are by the results of patient and neuroimaging studies, suggest that space and the posterior right human hippocampus are intimately linked.

Given the macroscopic level of our analyses, the data do not speak directly to the microscopic mechanisms, such as neurogenesis ( 31- 33), that might underlie the structural change we report herein. The differential changes in posterior and anterior hippocampus may represent two separate processes. The most parsimonious explanation, however, is that our findings reflect an overall internal reorganization of hippocampal circuitry ( 34) in response to a need to store an increasingly detailed spatial representation, where changes in one hippocampal region are very likely to affect others. On a broader level, the demonstration that normal activities can induce changes in the relative volume of gray matter in the brain has obvious implications for rehabilitation of those who have suffered brain injury or disease. It remains to be seen whether similar environment-related plasticity is possible in other regions of the human brain outside of the hippocampus.

Acknowledgments

E.A.M., I.S.J., C.D.G., J.A., R.S.J.F., and C.D.F. are supported by the Wellcome Trust. D.G.G. thanks the Wellcome Trust for its support at the Institute of Child Health. We are grateful for the assistance of Helen Gallagher, Amanda Brennan, and Jon Galliers. We also thank Andrew Holmes, Cheryl Johnson, and David McGonigle.

Abbreviations

VBM

voxel-based morphometry

ICV

intracranial volume

Footnotes

References

1. O'Keefe J, Nadel L. The Hippocampus as a Cognitive Map. Oxford: Clarendon; 1978. [Google Scholar]

2. Lee D W, Miyasato L E, Clayton N S. NeuroReport. 1998;9:R15-R27. [PubMed] [Google Scholar]

11. Talairach J, Tournoux P. Coplanar Stereotactic Atlas of the Human Brain. Stuttgart: Thieme; 1988. [Google Scholar]

14. Duvernoy H M. The Human Hippocampus. Berlin: Springer; 1998. [Google Scholar]

26. Squire L R, Knowlton B. In: The Cognitive Neurosciences. Gazzaniga M S, editor. Cambridge, MA: MIT Press; 1995. pp. 825-837. [Google Scholar]

34. Rapp P R, Stack E C, Gallagher M. J Comp Neurol. 1999;403:459-470. [PubMed] [Google Scholar]

Articles from Proceedings of the National Academy of Sciences of the United States of America are provided here courtesy of National Academy of Sciences

# data[].attributes.attachment_link.title
Navigation-related structural change in the hippocampi of taxi drivers

# data[].attributes.attachment_link.description
Structural MRIs of the brains of humans with extensive navigation experience, licensed London taxi drivers, were analyzed and compared with those of control subjects who did not drive taxis. The posterior hippocampi of taxi drivers were ...

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The study can be said to be androcentric as all of the participants were male; making it less generalisable. The study was matched participants as in they were all male, right handed and from london.

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This was effected in the occupations and hobbies of the control groups weren't taken into account where a job in navigation or spatial awareness could affect hippocampal volume.

Ecological validity was considered high as the MRI scanner doesnt effect the brain so the conditions were what they would be like day to day.

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Voxel based morphology showed the only brain areas with a significant difference between taxi drivers and the control group was the hippocampus, this being larger significantly larger on average for the group of taxi drivers. It was also found that for the taxi driver group the longer the participant had been a taxi driver the larger the hippocampus was.

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The knowledge is a test undergone by London taxi drivers, before anyone is allowed to drive a London black cab they will need to pass a test known commonly as the Knowledge. This typically takes 4 years to complete and involves knowing all of the roads around London and back routes.

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As taxis can be hailed in the street and asked to go anywhere, taxi drivers must have a thorough knowledge of London. This is why taxi drivers have to learn and pass the world-famous Knowledge.

London's taxi service is the best in the world, in part because our cab drivers know the quickest routes through London's complicated road network. There are thousands of streets and landmarks within a six mile radius of Charing Cross. Anyone who wants to drive an iconic London cab must memorize them all: the Knowledge of London.

The Knowledge was introduced as a requirement for taxi drivers in 1865.

Mastering the Knowledge typically takes students three to four years; it's a challenge, but plenty of help and support is available if you are determined.

As a taxi driver, you can choose when and where you work and how much you earn. Do you have the pride and passion it takes to become a London cabbie?

Download our Knowledge of London prospectus here, to find out how you can become a London taxi driver.

Learning the Knowledge

There are two different types of London taxi drivers:

All London (green badge) - Drivers can ply for hire anywhere in the Greater London Authority area

Suburban (yellow badge) - Drivers can ply for hire in one of the nine sectors in the suburbs of the Greater London Authority area

Whichever licence you choose to apply for, you will have to accumulate an encyclopedic knowledge of the streets and places of interest in that area. This will prove you can navigate your way around the Capital.

To become a London taxi driver you need to send us an application. Find out about applying for a taxi driver licence.

Following satisfactory character and medical checks, you will be sent a Knowledge of London introductory pack.

In this pack you will be given:

A copy of the guide to learning the Knowledge of London (the Blue Book)

A booklet of advice on how to learn the Knowledge and how you will be assessed

The Blue Book lists 320 routes (known as "runs") within the six mile radius of Charing Cross. You will need to learn these routes, plus all the roads and landmarks within a quarter mile radius of the start and end points of each route.

Knowledge of London Initial talk

You will be invited to attend an initial talk with other successful candidates. Here you will receive advice from a Knowledge of London examiner about the different stages of the Knowledge and the best way to approach your studies.

The Knowledge is done in seven stages, which are outlined here.

Stage 1: Self assessment

To check you're on the right track, within six months of starting you can take the self-assessment, which is based on the first 80 runs in the Blue Book. Taking the self-assessment is optional and no record of the result is made.

Stage 2: Written examination

When you are ready, you will sit the written examination. You will be tested on your knowledge of the Blue Book runs (five questions) and the major landmarks ("points") along the way (25 questions). This is a multiple choice test and the pass mark is 60%. This test must be undertaken within two years of being sent your introductory pack.

Stages 3-5: Appearances

You will then attend a series of one-to-one oral "appearances" with an examiner. Each appearance usually consists of four questions about the shortest route between any two points in London. An appearance takes about 20 minutes, and you'll get a score from A-D.

Depending on your score you will accumulate points; when you have enough you will progress to the next stage, when appearances will become more frequent. However, if you get too many Ds, you may be put back to a previous stage.

At Stage 3, appearances are about 56 days apart, at Stage 4 they are about 28 days apart, and at Stage 5 they are about 21 days apart. On average you will have to score on four appearances to accumulate enough points to progress to the next stage.

Stage 6: Suburban examination

You will need to demonstrate a good working knowledge of London's suburbs by learning an additional 25 routes.

Stage 7: Licence application and pre-licensing talk

Well done! You can make the final application for the issue of your licence. You will then join a group of other successful candidates to receive advice about your responsibilities as a taxi driver from a Knowledge of London examiner. You will also be given your badge and licence at the talk.

Download a detailed description of the Knowledge test.

Download a copy of the appearance guidance notes for examiners.

Using a scooter

Most people who apply to become a licensed taxi driver and take the Knowledge of London exam use a scooter to help learn the runs.

For information about riding a scooter or bike safely visit ScooterSafe-London or BikeSafe-London.

Knowledge schools

You may want to attend one of several Knowledge schools to help you study for appearances. These are independent schools that are not controlled or regulated by Transport for London.

Knowledge Point School

Open: Monday to Thursday 09:00 to 19:45, Friday 09:00 to 17:00. (Knowledge Point West open Monday to Friday 09:00 to 21:00.)
About: Established in 1985, Knowledge Point is London's most central and well established Knowledge school. We are placed between Kings Cross and Caledonian Road Station and have a second location in West London. We have classes and facilities to accommodate all levels of Knowledge students and our teachers are not only qualified taxi drivers but qualified teachers also. We understand that the Knowledge is not only about runs or points. KOL is more than that. It's a way of life. It's a language. It's a culture.
Email: admin@taxitradepromotions.co.uk
Website: www.taxitradepromotions.co.uk
Twitter:@taxitradepro / Facebook: Knowledge Point School Limited / Instagram: Knowledge Point School
Phone: Knowledge Point Central 0207 700 3999, Knowledge Point West 020 8961 9996
Address: Knowledge Point Central, 39-41 Brewery Road (1st Floor London Taxi Company headquarters), Islington, London N7 9QH
Knowledge Point West, 7 Cullen Way, London NW10 6JZ

WizAnn

E4 Knowledge School in Chingford

Open: Monday to Friday 10:00 to 22:00, except Tuesday 10:00 to 18:00 (classes/call-over rooms).
About: Family-run school. Opens occasional weekends. Offers all-inclusive package.
Email: e4kol@aim.com
Address: Jubilee Sports Ground, The Avenue, Highams Park, London E4 9RZ

The London Knowledge School

BKS

The Knowledge Practice

Open: Tuesday and Thursday 11:00 to 17:00.
About: Daily class 11:00 to 14:00 working through points sheet. Call-over session for all levels 14:00 to 17:00, along with 1-2-1 tuition.
Email: info@knowledgepractice.co.uk
Website: www.knowledgepractice.co.uk
Twitter:@k_practice
Phone: 07940 396 738
Address: Tooting Baptist Church, Longley Road, Tooting SW17 9LD

Sherbet London Knowledge College

Rankins

Phone: 07932 605 422
Address: Karibu Education Centre, 7 Gresham Road, Brixton, London SW9 7PH

The 5 Star Knowledge School

Email: theknowledgeschool20@gmail.com
Twitter:@GBKNOWLEDGE
Address: Bexley Football Club, St Marys Recreation Ground, Lesley Close, Bexley DA5 1LX

Knowledgepics

Yellow Badge East (sector 1)

Phone: 07963 082 390

Contact the Knowledge department

If you have any special needs or learning difficulties such as dyslexia please contact the Knowledge department to ensure that you receive reasonable adjustments at your appearances. You will be required to send proof to ensure appropriate adjustments are made.

If at any time during the examination process you have a complaint or a query you should contact us. All complaints and appeals are treated in confidence and will not have any adverse effect on your progress through the examination system.

While studying the Knowledge you are obliged to notify us of any changes in your status, such as the following:

Change of name and address

Any cautions, convictions or charges

Further information such as Driving Standards Agency Certificate

How to contact us:

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Transport for London | Every Journey Matters

# data[].attributes.attachment_link.description
As taxis can be hailed in the street and asked to go anywhere, taxi drivers must have a thorough knowledge of London. This is why taxi drivers have to learn and pass the world-famous Knowledge. London's taxi service is the best in the world, in part because our cab drivers know the quickest routes through London's complicated road network.

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This lead to the conclusion that a need in the environment for spatial awareness and navigation increases the hippocampal volume rather then people becoming taxi drivers due to having a large hippocampus. Due to the result in which it was found the longer they had been taxi drivers for the larger the hippocampus was.